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Created November 9, 2012 22:27
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A Comprehensive Super Mario Bros. Disassembly
;SMBDIS.ASM - A COMPREHENSIVE SUPER MARIO BROS. DISASSEMBLY
;by doppelganger ([email protected])
;This file is provided for your own use as-is. It will require the character rom data
;and an iNES file header to get it to work.
;There are so many people I have to thank for this, that taking all the credit for
;myself would be an unforgivable act of arrogance. Without their help this would
;probably not be possible. So I thank all the peeps in the nesdev scene whose insight into
;the 6502 and the NES helped me learn how it works (you guys know who you are, there's no
;way I could have done this without your help), as well as the authors of x816 and SMB
;Utility, and the reverse-engineers who did the original Super Mario Bros. Hacking Project,
;which I compared notes with but did not copy from. Last but certainly not least, I thank
;Nintendo for creating this game and the NES, without which this disassembly would
;only be theory.
;Assembles with x816.
;-------------------------------------------------------------------------------------
;DEFINES
;NES specific hardware defines
PPU_CTRL_REG1 = $2000
PPU_CTRL_REG2 = $2001
PPU_STATUS = $2002
PPU_SPR_ADDR = $2003
PPU_SPR_DATA = $2004
PPU_SCROLL_REG = $2005
PPU_ADDRESS = $2006
PPU_DATA = $2007
SND_REGISTER = $4000
SND_SQUARE1_REG = $4000
SND_SQUARE2_REG = $4004
SND_TRIANGLE_REG = $4008
SND_NOISE_REG = $400c
SND_DELTA_REG = $4010
SND_MASTERCTRL_REG = $4015
SPR_DMA = $4014
JOYPAD_PORT = $4016
JOYPAD_PORT1 = $4016
JOYPAD_PORT2 = $4017
; GAME SPECIFIC DEFINES
ObjectOffset = $08
FrameCounter = $09
SavedJoypadBits = $06fc
SavedJoypad1Bits = $06fc
SavedJoypad2Bits = $06fd
JoypadBitMask = $074a
JoypadOverride = $0758
A_B_Buttons = $0a
PreviousA_B_Buttons = $0d
Up_Down_Buttons = $0b
Left_Right_Buttons = $0c
GameEngineSubroutine = $0e
Mirror_PPU_CTRL_REG1 = $0778
Mirror_PPU_CTRL_REG2 = $0779
OperMode = $0770
OperMode_Task = $0772
ScreenRoutineTask = $073c
GamePauseStatus = $0776
GamePauseTimer = $0777
DemoAction = $0717
DemoActionTimer = $0718
TimerControl = $0747
IntervalTimerControl = $077f
Timers = $0780
SelectTimer = $0780
PlayerAnimTimer = $0781
JumpSwimTimer = $0782
RunningTimer = $0783
BlockBounceTimer = $0784
SideCollisionTimer = $0785
JumpspringTimer = $0786
GameTimerCtrlTimer = $0787
ClimbSideTimer = $0789
EnemyFrameTimer = $078a
FrenzyEnemyTimer = $078f
BowserFireBreathTimer = $0790
StompTimer = $0791
AirBubbleTimer = $0792
ScrollIntervalTimer = $0795
EnemyIntervalTimer = $0796
BrickCoinTimer = $079d
InjuryTimer = $079e
StarInvincibleTimer = $079f
ScreenTimer = $07a0
WorldEndTimer = $07a1
DemoTimer = $07a2
Sprite_Data = $0200
Sprite_Y_Position = $0200
Sprite_Tilenumber = $0201
Sprite_Attributes = $0202
Sprite_X_Position = $0203
ScreenEdge_PageLoc = $071a
ScreenEdge_X_Pos = $071c
ScreenLeft_PageLoc = $071a
ScreenRight_PageLoc = $071b
ScreenLeft_X_Pos = $071c
ScreenRight_X_Pos = $071d
PlayerFacingDir = $33
DestinationPageLoc = $34
VictoryWalkControl = $35
ScrollFractional = $0768
PrimaryMsgCounter = $0719
SecondaryMsgCounter = $0749
HorizontalScroll = $073f
VerticalScroll = $0740
ScrollLock = $0723
ScrollThirtyTwo = $073d
Player_X_Scroll = $06ff
Player_Pos_ForScroll = $0755
ScrollAmount = $0775
AreaData = $e7
AreaDataLow = $e7
AreaDataHigh = $e8
EnemyData = $e9
EnemyDataLow = $e9
EnemyDataHigh = $ea
AreaParserTaskNum = $071f
ColumnSets = $071e
CurrentPageLoc = $0725
CurrentColumnPos = $0726
BackloadingFlag = $0728
BehindAreaParserFlag = $0729
AreaObjectPageLoc = $072a
AreaObjectPageSel = $072b
AreaDataOffset = $072c
AreaObjOffsetBuffer = $072d
AreaObjectLength = $0730
StaircaseControl = $0734
AreaObjectHeight = $0735
MushroomLedgeHalfLen = $0736
EnemyDataOffset = $0739
EnemyObjectPageLoc = $073a
EnemyObjectPageSel = $073b
MetatileBuffer = $06a1
BlockBufferColumnPos = $06a0
CurrentNTAddr_Low = $0721
CurrentNTAddr_High = $0720
AttributeBuffer = $03f9
LoopCommand = $0745
DisplayDigits = $07d7
TopScoreDisplay = $07d7
ScoreAndCoinDisplay = $07dd
PlayerScoreDisplay = $07dd
GameTimerDisplay = $07f8
DigitModifier = $0134
VerticalFlipFlag = $0109
FloateyNum_Control = $0110
ShellChainCounter = $0125
FloateyNum_Timer = $012c
FloateyNum_X_Pos = $0117
FloateyNum_Y_Pos = $011e
FlagpoleFNum_Y_Pos = $010d
FlagpoleFNum_YMFDummy = $010e
FlagpoleScore = $010f
FlagpoleCollisionYPos = $070f
StompChainCounter = $0484
VRAM_Buffer1_Offset = $0300
VRAM_Buffer1 = $0301
VRAM_Buffer2_Offset = $0340
VRAM_Buffer2 = $0341
VRAM_Buffer_AddrCtrl = $0773
Sprite0HitDetectFlag = $0722
DisableScreenFlag = $0774
DisableIntermediate = $0769
ColorRotateOffset = $06d4
TerrainControl = $0727
AreaStyle = $0733
ForegroundScenery = $0741
BackgroundScenery = $0742
CloudTypeOverride = $0743
BackgroundColorCtrl = $0744
AreaType = $074e
AreaAddrsLOffset = $074f
AreaPointer = $0750
PlayerEntranceCtrl = $0710
GameTimerSetting = $0715
AltEntranceControl = $0752
EntrancePage = $0751
NumberOfPlayers = $077a
WarpZoneControl = $06d6
ChangeAreaTimer = $06de
MultiLoopCorrectCntr = $06d9
MultiLoopPassCntr = $06da
FetchNewGameTimerFlag = $0757
GameTimerExpiredFlag = $0759
PrimaryHardMode = $076a
SecondaryHardMode = $06cc
WorldSelectNumber = $076b
WorldSelectEnableFlag = $07fc
ContinueWorld = $07fd
CurrentPlayer = $0753
PlayerSize = $0754
PlayerStatus = $0756
OnscreenPlayerInfo = $075a
NumberofLives = $075a ;used by current player
HalfwayPage = $075b
LevelNumber = $075c ;the actual dash number
Hidden1UpFlag = $075d
CoinTally = $075e
WorldNumber = $075f
AreaNumber = $0760 ;internal number used to find areas
CoinTallyFor1Ups = $0748
OffscreenPlayerInfo = $0761
OffScr_NumberofLives = $0761 ;used by offscreen player
OffScr_HalfwayPage = $0762
OffScr_LevelNumber = $0763
OffScr_Hidden1UpFlag = $0764
OffScr_CoinTally = $0765
OffScr_WorldNumber = $0766
OffScr_AreaNumber = $0767
BalPlatformAlignment = $03a0
Platform_X_Scroll = $03a1
PlatformCollisionFlag = $03a2
YPlatformTopYPos = $0401
YPlatformCenterYPos = $58
BrickCoinTimerFlag = $06bc
StarFlagTaskControl = $0746
PseudoRandomBitReg = $07a7
WarmBootValidation = $07ff
SprShuffleAmtOffset = $06e0
SprShuffleAmt = $06e1
SprDataOffset = $06e4
Player_SprDataOffset = $06e4
Enemy_SprDataOffset = $06e5
Block_SprDataOffset = $06ec
Alt_SprDataOffset = $06ec
Bubble_SprDataOffset = $06ee
FBall_SprDataOffset = $06f1
Misc_SprDataOffset = $06f3
SprDataOffset_Ctrl = $03ee
Player_State = $1d
Enemy_State = $1e
Fireball_State = $24
Block_State = $26
Misc_State = $2a
Player_MovingDir = $45
Enemy_MovingDir = $46
SprObject_X_Speed = $57
Player_X_Speed = $57
Enemy_X_Speed = $58
Fireball_X_Speed = $5e
Block_X_Speed = $60
Misc_X_Speed = $64
Jumpspring_FixedYPos = $58
JumpspringAnimCtrl = $070e
JumpspringForce = $06db
SprObject_PageLoc = $6d
Player_PageLoc = $6d
Enemy_PageLoc = $6e
Fireball_PageLoc = $74
Block_PageLoc = $76
Misc_PageLoc = $7a
Bubble_PageLoc = $83
SprObject_X_Position = $86
Player_X_Position = $86
Enemy_X_Position = $87
Fireball_X_Position = $8d
Block_X_Position = $8f
Misc_X_Position = $93
Bubble_X_Position = $9c
SprObject_Y_Speed = $9f
Player_Y_Speed = $9f
Enemy_Y_Speed = $a0
Fireball_Y_Speed = $a6
Block_Y_Speed = $a8
Misc_Y_Speed = $ac
SprObject_Y_HighPos = $b5
Player_Y_HighPos = $b5
Enemy_Y_HighPos = $b6
Fireball_Y_HighPos = $bc
Block_Y_HighPos = $be
Misc_Y_HighPos = $c2
Bubble_Y_HighPos = $cb
SprObject_Y_Position = $ce
Player_Y_Position = $ce
Enemy_Y_Position = $cf
Fireball_Y_Position = $d5
Block_Y_Position = $d7
Misc_Y_Position = $db
Bubble_Y_Position = $e4
SprObject_Rel_XPos = $03ad
Player_Rel_XPos = $03ad
Enemy_Rel_XPos = $03ae
Fireball_Rel_XPos = $03af
Bubble_Rel_XPos = $03b0
Block_Rel_XPos = $03b1
Misc_Rel_XPos = $03b3
SprObject_Rel_YPos = $03b8
Player_Rel_YPos = $03b8
Enemy_Rel_YPos = $03b9
Fireball_Rel_YPos = $03ba
Bubble_Rel_YPos = $03bb
Block_Rel_YPos = $03bc
Misc_Rel_YPos = $03be
SprObject_SprAttrib = $03c4
Player_SprAttrib = $03c4
Enemy_SprAttrib = $03c5
SprObject_X_MoveForce = $0400
Enemy_X_MoveForce = $0401
SprObject_YMF_Dummy = $0416
Player_YMF_Dummy = $0416
Enemy_YMF_Dummy = $0417
Bubble_YMF_Dummy = $042c
SprObject_Y_MoveForce = $0433
Player_Y_MoveForce = $0433
Enemy_Y_MoveForce = $0434
Block_Y_MoveForce = $043c
DisableCollisionDet = $0716
Player_CollisionBits = $0490
Enemy_CollisionBits = $0491
SprObj_BoundBoxCtrl = $0499
Player_BoundBoxCtrl = $0499
Enemy_BoundBoxCtrl = $049a
Fireball_BoundBoxCtrl = $04a0
Misc_BoundBoxCtrl = $04a2
EnemyFrenzyBuffer = $06cb
EnemyFrenzyQueue = $06cd
Enemy_Flag = $0f
Enemy_ID = $16
PlayerGfxOffset = $06d5
Player_XSpeedAbsolute = $0700
FrictionAdderHigh = $0701
FrictionAdderLow = $0702
RunningSpeed = $0703
SwimmingFlag = $0704
Player_X_MoveForce = $0705
DiffToHaltJump = $0706
JumpOrigin_Y_HighPos = $0707
JumpOrigin_Y_Position = $0708
VerticalForce = $0709
VerticalForceDown = $070a
PlayerChangeSizeFlag = $070b
PlayerAnimTimerSet = $070c
PlayerAnimCtrl = $070d
DeathMusicLoaded = $0712
FlagpoleSoundQueue = $0713
CrouchingFlag = $0714
MaximumLeftSpeed = $0450
MaximumRightSpeed = $0456
SprObject_OffscrBits = $03d0
Player_OffscreenBits = $03d0
Enemy_OffscreenBits = $03d1
FBall_OffscreenBits = $03d2
Bubble_OffscreenBits = $03d3
Block_OffscreenBits = $03d4
Misc_OffscreenBits = $03d6
EnemyOffscrBitsMasked = $03d8
Cannon_Offset = $046a
Cannon_PageLoc = $046b
Cannon_X_Position = $0471
Cannon_Y_Position = $0477
Cannon_Timer = $047d
Whirlpool_Offset = $046a
Whirlpool_PageLoc = $046b
Whirlpool_LeftExtent = $0471
Whirlpool_Length = $0477
Whirlpool_Flag = $047d
VineFlagOffset = $0398
VineHeight = $0399
VineObjOffset = $039a
VineStart_Y_Position = $039d
Block_Orig_YPos = $03e4
Block_BBuf_Low = $03e6
Block_Metatile = $03e8
Block_PageLoc2 = $03ea
Block_RepFlag = $03ec
Block_ResidualCounter = $03f0
Block_Orig_XPos = $03f1
BoundingBox_UL_XPos = $04ac
BoundingBox_UL_YPos = $04ad
BoundingBox_DR_XPos = $04ae
BoundingBox_DR_YPos = $04af
BoundingBox_UL_Corner = $04ac
BoundingBox_LR_Corner = $04ae
EnemyBoundingBoxCoord = $04b0
PowerUpType = $39
FireballBouncingFlag = $3a
FireballCounter = $06ce
FireballThrowingTimer = $0711
HammerEnemyOffset = $06ae
JumpCoinMiscOffset = $06b7
Block_Buffer_1 = $0500
Block_Buffer_2 = $05d0
HammerThrowingTimer = $03a2
HammerBroJumpTimer = $3c
Misc_Collision_Flag = $06be
RedPTroopaOrigXPos = $0401
RedPTroopaCenterYPos = $58
XMovePrimaryCounter = $a0
XMoveSecondaryCounter = $58
CheepCheepMoveMFlag = $58
CheepCheepOrigYPos = $0434
BitMFilter = $06dd
LakituReappearTimer = $06d1
LakituMoveSpeed = $58
LakituMoveDirection = $a0
FirebarSpinState_Low = $58
FirebarSpinState_High = $a0
FirebarSpinSpeed = $0388
FirebarSpinDirection = $34
DuplicateObj_Offset = $06cf
NumberofGroupEnemies = $06d3
BlooperMoveCounter = $a0
BlooperMoveSpeed = $58
BowserBodyControls = $0363
BowserFeetCounter = $0364
BowserMovementSpeed = $0365
BowserOrigXPos = $0366
BowserFlameTimerCtrl = $0367
BowserFront_Offset = $0368
BridgeCollapseOffset = $0369
BowserGfxFlag = $036a
BowserHitPoints = $0483
MaxRangeFromOrigin = $06dc
BowserFlamePRandomOfs = $0417
PiranhaPlantUpYPos = $0417
PiranhaPlantDownYPos = $0434
PiranhaPlant_Y_Speed = $58
PiranhaPlant_MoveFlag = $a0
FireworksCounter = $06d7
ExplosionGfxCounter = $58
ExplosionTimerCounter = $a0
;sound related defines
Squ2_NoteLenBuffer = $07b3
Squ2_NoteLenCounter = $07b4
Squ2_EnvelopeDataCtrl = $07b5
Squ1_NoteLenCounter = $07b6
Squ1_EnvelopeDataCtrl = $07b7
Tri_NoteLenBuffer = $07b8
Tri_NoteLenCounter = $07b9
Noise_BeatLenCounter = $07ba
Squ1_SfxLenCounter = $07bb
Squ2_SfxLenCounter = $07bd
Sfx_SecondaryCounter = $07be
Noise_SfxLenCounter = $07bf
PauseSoundQueue = $fa
Square1SoundQueue = $ff
Square2SoundQueue = $fe
NoiseSoundQueue = $fd
AreaMusicQueue = $fb
EventMusicQueue = $fc
Square1SoundBuffer = $f1
Square2SoundBuffer = $f2
NoiseSoundBuffer = $f3
AreaMusicBuffer = $f4
EventMusicBuffer = $07b1
PauseSoundBuffer = $07b2
MusicData = $f5
MusicDataLow = $f5
MusicDataHigh = $f6
MusicOffset_Square2 = $f7
MusicOffset_Square1 = $f8
MusicOffset_Triangle = $f9
MusicOffset_Noise = $07b0
NoteLenLookupTblOfs = $f0
DAC_Counter = $07c0
NoiseDataLoopbackOfs = $07c1
NoteLengthTblAdder = $07c4
AreaMusicBuffer_Alt = $07c5
PauseModeFlag = $07c6
GroundMusicHeaderOfs = $07c7
AltRegContentFlag = $07ca
;-------------------------------------------------------------------------------------
;CONSTANTS
;sound effects constants
Sfx_SmallJump = %10000000
Sfx_Flagpole = %01000000
Sfx_Fireball = %00100000
Sfx_PipeDown_Injury = %00010000
Sfx_EnemySmack = %00001000
Sfx_EnemyStomp = %00000100
Sfx_Bump = %00000010
Sfx_BigJump = %00000001
Sfx_BowserFall = %10000000
Sfx_ExtraLife = %01000000
Sfx_PowerUpGrab = %00100000
Sfx_TimerTick = %00010000
Sfx_Blast = %00001000
Sfx_GrowVine = %00000100
Sfx_GrowPowerUp = %00000010
Sfx_CoinGrab = %00000001
Sfx_BowserFlame = %00000010
Sfx_BrickShatter = %00000001
;music constants
Silence = %10000000
StarPowerMusic = %01000000
PipeIntroMusic = %00100000
CloudMusic = %00010000
CastleMusic = %00001000
UndergroundMusic = %00000100
WaterMusic = %00000010
GroundMusic = %00000001
TimeRunningOutMusic = %01000000
EndOfLevelMusic = %00100000
AltGameOverMusic = %00010000
EndOfCastleMusic = %00001000
VictoryMusic = %00000100
GameOverMusic = %00000010
DeathMusic = %00000001
;enemy object constants
GreenKoopa = $00
BuzzyBeetle = $02
RedKoopa = $03
HammerBro = $05
Goomba = $06
Bloober = $07
BulletBill_FrenzyVar = $08
GreyCheepCheep = $0a
RedCheepCheep = $0b
Podoboo = $0c
PiranhaPlant = $0d
GreenParatroopaJump = $0e
RedParatroopa = $0f
GreenParatroopaFly = $10
Lakitu = $11
Spiny = $12
FlyCheepCheepFrenzy = $14
FlyingCheepCheep = $14
BowserFlame = $15
Fireworks = $16
BBill_CCheep_Frenzy = $17
Stop_Frenzy = $18
Bowser = $2d
PowerUpObject = $2e
VineObject = $2f
FlagpoleFlagObject = $30
StarFlagObject = $31
JumpspringObject = $32
BulletBill_CannonVar = $33
RetainerObject = $35
TallEnemy = $09
;other constants
World1 = 0
World2 = 1
World3 = 2
World4 = 3
World5 = 4
World6 = 5
World7 = 6
World8 = 7
Level1 = 0
Level2 = 1
Level3 = 2
Level4 = 3
WarmBootOffset = <$07d6
ColdBootOffset = <$07fe
TitleScreenDataOffset = $1ec0
SoundMemory = $07b0
SwimTileRepOffset = PlayerGraphicsTable + $9e
MusicHeaderOffsetData = MusicHeaderData - 1
MHD = MusicHeaderData
A_Button = %10000000
B_Button = %01000000
Select_Button = %00100000
Start_Button = %00010000
Up_Dir = %00001000
Down_Dir = %00000100
Left_Dir = %00000010
Right_Dir = %00000001
TitleScreenModeValue = 0
GameModeValue = 1
VictoryModeValue = 2
GameOverModeValue = 3
;-------------------------------------------------------------------------------------
;DIRECTIVES
.index 8
.mem 8
.org $8000
;-------------------------------------------------------------------------------------
Start:
sei ;pretty standard 6502 type init here
cld
lda #%00010000 ;init PPU control register 1
sta PPU_CTRL_REG1
ldx #$ff ;reset stack pointer
txs
VBlank1: lda PPU_STATUS ;wait two frames
bpl VBlank1
VBlank2: lda PPU_STATUS
bpl VBlank2
ldy #ColdBootOffset ;load default cold boot pointer
ldx #$05 ;this is where we check for a warm boot
WBootCheck: lda TopScoreDisplay,x ;check each score digit in the top score
cmp #10 ;to see if we have a valid digit
bcs ColdBoot ;if not, give up and proceed with cold boot
dex
bpl WBootCheck
lda WarmBootValidation ;second checkpoint, check to see if
cmp #$a5 ;another location has a specific value
bne ColdBoot
ldy #WarmBootOffset ;if passed both, load warm boot pointer
ColdBoot: jsr InitializeMemory ;clear memory using pointer in Y
sta SND_DELTA_REG+1 ;reset delta counter load register
sta OperMode ;reset primary mode of operation
lda #$a5 ;set warm boot flag
sta WarmBootValidation
sta PseudoRandomBitReg ;set seed for pseudorandom register
lda #%00001111
sta SND_MASTERCTRL_REG ;enable all sound channels except dmc
lda #%00000110
sta PPU_CTRL_REG2 ;turn off clipping for OAM and background
jsr MoveAllSpritesOffscreen
jsr InitializeNameTables ;initialize both name tables
inc DisableScreenFlag ;set flag to disable screen output
lda Mirror_PPU_CTRL_REG1
ora #%10000000 ;enable NMIs
jsr WritePPUReg1
EndlessLoop: jmp EndlessLoop ;endless loop, need I say more?
;-------------------------------------------------------------------------------------
;$00 - vram buffer address table low, also used for pseudorandom bit
;$01 - vram buffer address table high
VRAM_AddrTable_Low:
.db <VRAM_Buffer1, <WaterPaletteData, <GroundPaletteData
.db <UndergroundPaletteData, <CastlePaletteData, <VRAM_Buffer1_Offset
.db <VRAM_Buffer2, <VRAM_Buffer2, <BowserPaletteData
.db <DaySnowPaletteData, <NightSnowPaletteData, <MushroomPaletteData
.db <MarioThanksMessage, <LuigiThanksMessage, <MushroomRetainerSaved
.db <PrincessSaved1, <PrincessSaved2, <WorldSelectMessage1
.db <WorldSelectMessage2
VRAM_AddrTable_High:
.db >VRAM_Buffer1, >WaterPaletteData, >GroundPaletteData
.db >UndergroundPaletteData, >CastlePaletteData, >VRAM_Buffer1_Offset
.db >VRAM_Buffer2, >VRAM_Buffer2, >BowserPaletteData
.db >DaySnowPaletteData, >NightSnowPaletteData, >MushroomPaletteData
.db >MarioThanksMessage, >LuigiThanksMessage, >MushroomRetainerSaved
.db >PrincessSaved1, >PrincessSaved2, >WorldSelectMessage1
.db >WorldSelectMessage2
VRAM_Buffer_Offset:
.db <VRAM_Buffer1_Offset, <VRAM_Buffer2_Offset
NonMaskableInterrupt:
lda Mirror_PPU_CTRL_REG1 ;disable NMIs in mirror reg
and #%01111111 ;save all other bits
sta Mirror_PPU_CTRL_REG1
and #%01111110 ;alter name table address to be $2800
sta PPU_CTRL_REG1 ;(essentially $2000) but save other bits
lda Mirror_PPU_CTRL_REG2 ;disable OAM and background display by default
and #%11100110
ldy DisableScreenFlag ;get screen disable flag
bne ScreenOff ;if set, used bits as-is
lda Mirror_PPU_CTRL_REG2 ;otherwise reenable bits and save them
ora #%00011110
ScreenOff: sta Mirror_PPU_CTRL_REG2 ;save bits for later but not in register at the moment
and #%11100111 ;disable screen for now
sta PPU_CTRL_REG2
ldx PPU_STATUS ;reset flip-flop and reset scroll registers to zero
lda #$00
jsr InitScroll
sta PPU_SPR_ADDR ;reset spr-ram address register
lda #$02 ;perform spr-ram DMA access on $0200-$02ff
sta SPR_DMA
ldx VRAM_Buffer_AddrCtrl ;load control for pointer to buffer contents
lda VRAM_AddrTable_Low,x ;set indirect at $00 to pointer
sta $00
lda VRAM_AddrTable_High,x
sta $01
jsr UpdateScreen ;update screen with buffer contents
ldy #$00
ldx VRAM_Buffer_AddrCtrl ;check for usage of $0341
cpx #$06
bne InitBuffer
iny ;get offset based on usage
InitBuffer: ldx VRAM_Buffer_Offset,y
lda #$00 ;clear buffer header at last location
sta VRAM_Buffer1_Offset,x
sta VRAM_Buffer1,x
sta VRAM_Buffer_AddrCtrl ;reinit address control to $0301
lda Mirror_PPU_CTRL_REG2 ;copy mirror of $2001 to register
sta PPU_CTRL_REG2
jsr SoundEngine ;play sound
jsr ReadJoypads ;read joypads
jsr PauseRoutine ;handle pause
jsr UpdateTopScore
lda GamePauseStatus ;check for pause status
lsr
bcs PauseSkip
lda TimerControl ;if master timer control not set, decrement
beq DecTimers ;all frame and interval timers
dec TimerControl
bne NoDecTimers
DecTimers: ldx #$14 ;load end offset for end of frame timers
dec IntervalTimerControl ;decrement interval timer control,
bpl DecTimersLoop ;if not expired, only frame timers will decrement
lda #$14
sta IntervalTimerControl ;if control for interval timers expired,
ldx #$23 ;interval timers will decrement along with frame timers
DecTimersLoop: lda Timers,x ;check current timer
beq SkipExpTimer ;if current timer expired, branch to skip,
dec Timers,x ;otherwise decrement the current timer
SkipExpTimer: dex ;move onto next timer
bpl DecTimersLoop ;do this until all timers are dealt with
NoDecTimers: inc FrameCounter ;increment frame counter
PauseSkip: ldx #$00
ldy #$07
lda PseudoRandomBitReg ;get first memory location of LSFR bytes
and #%00000010 ;mask out all but d1
sta $00 ;save here
lda PseudoRandomBitReg+1 ;get second memory location
and #%00000010 ;mask out all but d1
eor $00 ;perform exclusive-OR on d1 from first and second bytes
clc ;if neither or both are set, carry will be clear
beq RotPRandomBit
sec ;if one or the other is set, carry will be set
RotPRandomBit: ror PseudoRandomBitReg,x ;rotate carry into d7, and rotate last bit into carry
inx ;increment to next byte
dey ;decrement for loop
bne RotPRandomBit
lda Sprite0HitDetectFlag ;check for flag here
beq SkipSprite0
Sprite0Clr: lda PPU_STATUS ;wait for sprite 0 flag to clear, which will
and #%01000000 ;not happen until vblank has ended
bne Sprite0Clr
lda GamePauseStatus ;if in pause mode, do not bother with sprites at all
lsr
bcs Sprite0Hit
jsr MoveSpritesOffscreen
jsr SpriteShuffler
Sprite0Hit: lda PPU_STATUS ;do sprite #0 hit detection
and #%01000000
beq Sprite0Hit
ldy #$14 ;small delay, to wait until we hit horizontal blank time
HBlankDelay: dey
bne HBlankDelay
SkipSprite0: lda HorizontalScroll ;set scroll registers from variables
sta PPU_SCROLL_REG
lda VerticalScroll
sta PPU_SCROLL_REG
lda Mirror_PPU_CTRL_REG1 ;load saved mirror of $2000
pha
sta PPU_CTRL_REG1
lda GamePauseStatus ;if in pause mode, do not perform operation mode stuff
lsr
bcs SkipMainOper
jsr OperModeExecutionTree ;otherwise do one of many, many possible subroutines
SkipMainOper: lda PPU_STATUS ;reset flip-flop
pla
ora #%10000000 ;reactivate NMIs
sta PPU_CTRL_REG1
rti ;we are done until the next frame!
;-------------------------------------------------------------------------------------
PauseRoutine:
lda OperMode ;are we in victory mode?
cmp #VictoryModeValue ;if so, go ahead
beq ChkPauseTimer
cmp #GameModeValue ;are we in game mode?
bne ExitPause ;if not, leave
lda OperMode_Task ;if we are in game mode, are we running game engine?
cmp #$03
bne ExitPause ;if not, leave
ChkPauseTimer: lda GamePauseTimer ;check if pause timer is still counting down
beq ChkStart
dec GamePauseTimer ;if so, decrement and leave
rts
ChkStart: lda SavedJoypad1Bits ;check to see if start is pressed
and #Start_Button ;on controller 1
beq ClrPauseTimer
lda GamePauseStatus ;check to see if timer flag is set
and #%10000000 ;and if so, do not reset timer (residual,
bne ExitPause ;joypad reading routine makes this unnecessary)
lda #$2b ;set pause timer
sta GamePauseTimer
lda GamePauseStatus
tay
iny ;set pause sfx queue for next pause mode
sty PauseSoundQueue
eor #%00000001 ;invert d0 and set d7
ora #%10000000
bne SetPause ;unconditional branch
ClrPauseTimer: lda GamePauseStatus ;clear timer flag if timer is at zero and start button
and #%01111111 ;is not pressed
SetPause: sta GamePauseStatus
ExitPause: rts
;-------------------------------------------------------------------------------------
;$00 - used for preset value
SpriteShuffler:
ldy AreaType ;load level type, likely residual code
lda #$28 ;load preset value which will put it at
sta $00 ;sprite #10
ldx #$0e ;start at the end of OAM data offsets
ShuffleLoop: lda SprDataOffset,x ;check for offset value against
cmp $00 ;the preset value
bcc NextSprOffset ;if less, skip this part
ldy SprShuffleAmtOffset ;get current offset to preset value we want to add
clc
adc SprShuffleAmt,y ;get shuffle amount, add to current sprite offset
bcc StrSprOffset ;if not exceeded $ff, skip second add
clc
adc $00 ;otherwise add preset value $28 to offset
StrSprOffset: sta SprDataOffset,x ;store new offset here or old one if branched to here
NextSprOffset: dex ;move backwards to next one
bpl ShuffleLoop
ldx SprShuffleAmtOffset ;load offset
inx
cpx #$03 ;check if offset + 1 goes to 3
bne SetAmtOffset ;if offset + 1 not 3, store
ldx #$00 ;otherwise, init to 0
SetAmtOffset: stx SprShuffleAmtOffset
ldx #$08 ;load offsets for values and storage
ldy #$02
SetMiscOffset: lda SprDataOffset+5,y ;load one of three OAM data offsets
sta Misc_SprDataOffset-2,x ;store first one unmodified, but
clc ;add eight to the second and eight
adc #$08 ;more to the third one
sta Misc_SprDataOffset-1,x ;note that due to the way X is set up,
clc ;this code loads into the misc sprite offsets
adc #$08
sta Misc_SprDataOffset,x
dex
dex
dex
dey
bpl SetMiscOffset ;do this until all misc spr offsets are loaded
rts
;-------------------------------------------------------------------------------------
OperModeExecutionTree:
lda OperMode ;this is the heart of the entire program,
jsr JumpEngine ;most of what goes on starts here
.dw TitleScreenMode
.dw GameMode
.dw VictoryMode
.dw GameOverMode
;-------------------------------------------------------------------------------------
MoveAllSpritesOffscreen:
ldy #$00 ;this routine moves all sprites off the screen
.db $2c ;BIT instruction opcode
MoveSpritesOffscreen:
ldy #$04 ;this routine moves all but sprite 0
lda #$f8 ;off the screen
SprInitLoop: sta Sprite_Y_Position,y ;write 248 into OAM data's Y coordinate
iny ;which will move it off the screen
iny
iny
iny
bne SprInitLoop
rts
;-------------------------------------------------------------------------------------
TitleScreenMode:
lda OperMode_Task
jsr JumpEngine
.dw InitializeGame
.dw ScreenRoutines
.dw PrimaryGameSetup
.dw GameMenuRoutine
;-------------------------------------------------------------------------------------
WSelectBufferTemplate:
.db $04, $20, $73, $01, $00, $00
GameMenuRoutine:
ldy #$00
lda SavedJoypad1Bits ;check to see if either player pressed
ora SavedJoypad2Bits ;only the start button (either joypad)
cmp #Start_Button
beq StartGame
cmp #A_Button+Start_Button ;check to see if A + start was pressed
bne ChkSelect ;if not, branch to check select button
StartGame: jmp ChkContinue ;if either start or A + start, execute here
ChkSelect: cmp #Select_Button ;check to see if the select button was pressed
beq SelectBLogic ;if so, branch reset demo timer
ldx DemoTimer ;otherwise check demo timer
bne ChkWorldSel ;if demo timer not expired, branch to check world selection
sta SelectTimer ;set controller bits here if running demo
jsr DemoEngine ;run through the demo actions
bcs ResetTitle ;if carry flag set, demo over, thus branch
jmp RunDemo ;otherwise, run game engine for demo
ChkWorldSel: ldx WorldSelectEnableFlag ;check to see if world selection has been enabled
beq NullJoypad
cmp #B_Button ;if so, check to see if the B button was pressed
bne NullJoypad
iny ;if so, increment Y and execute same code as select
SelectBLogic: lda DemoTimer ;if select or B pressed, check demo timer one last time
beq ResetTitle ;if demo timer expired, branch to reset title screen mode
lda #$18 ;otherwise reset demo timer
sta DemoTimer
lda SelectTimer ;check select/B button timer
bne NullJoypad ;if not expired, branch
lda #$10 ;otherwise reset select button timer
sta SelectTimer
cpy #$01 ;was the B button pressed earlier? if so, branch
beq IncWorldSel ;note this will not be run if world selection is disabled
lda NumberOfPlayers ;if no, must have been the select button, therefore
eor #%00000001 ;change number of players and draw icon accordingly
sta NumberOfPlayers
jsr DrawMushroomIcon
jmp NullJoypad
IncWorldSel: ldx WorldSelectNumber ;increment world select number
inx
txa
and #%00000111 ;mask out higher bits
sta WorldSelectNumber ;store as current world select number
jsr GoContinue
UpdateShroom: lda WSelectBufferTemplate,x ;write template for world select in vram buffer
sta VRAM_Buffer1-1,x ;do this until all bytes are written
inx
cpx #$06
bmi UpdateShroom
ldy WorldNumber ;get world number from variable and increment for
iny ;proper display, and put in blank byte before
sty VRAM_Buffer1+3 ;null terminator
NullJoypad: lda #$00 ;clear joypad bits for player 1
sta SavedJoypad1Bits
RunDemo: jsr GameCoreRoutine ;run game engine
lda GameEngineSubroutine ;check to see if we're running lose life routine
cmp #$06
bne ExitMenu ;if not, do not do all the resetting below
ResetTitle: lda #$00 ;reset game modes, disable
sta OperMode ;sprite 0 check and disable
sta OperMode_Task ;screen output
sta Sprite0HitDetectFlag
inc DisableScreenFlag
rts
ChkContinue: ldy DemoTimer ;if timer for demo has expired, reset modes
beq ResetTitle
asl ;check to see if A button was also pushed
bcc StartWorld1 ;if not, don't load continue function's world number
lda ContinueWorld ;load previously saved world number for secret
jsr GoContinue ;continue function when pressing A + start
StartWorld1: jsr LoadAreaPointer
inc Hidden1UpFlag ;set 1-up box flag for both players
inc OffScr_Hidden1UpFlag
inc FetchNewGameTimerFlag ;set fetch new game timer flag
inc OperMode ;set next game mode
lda WorldSelectEnableFlag ;if world select flag is on, then primary
sta PrimaryHardMode ;hard mode must be on as well
lda #$00
sta OperMode_Task ;set game mode here, and clear demo timer
sta DemoTimer
ldx #$17
lda #$00
InitScores: sta ScoreAndCoinDisplay,x ;clear player scores and coin displays
dex
bpl InitScores
ExitMenu: rts
GoContinue: sta WorldNumber ;start both players at the first area
sta OffScr_WorldNumber ;of the previously saved world number
ldx #$00 ;note that on power-up using this function
stx AreaNumber ;will make no difference
stx OffScr_AreaNumber
rts
;-------------------------------------------------------------------------------------
MushroomIconData:
.db $07, $22, $49, $83, $ce, $24, $24, $00
DrawMushroomIcon:
ldy #$07 ;read eight bytes to be read by transfer routine
IconDataRead: lda MushroomIconData,y ;note that the default position is set for a
sta VRAM_Buffer1-1,y ;1-player game
dey
bpl IconDataRead
lda NumberOfPlayers ;check number of players
beq ExitIcon ;if set to 1-player game, we're done
lda #$24 ;otherwise, load blank tile in 1-player position
sta VRAM_Buffer1+3
lda #$ce ;then load shroom icon tile in 2-player position
sta VRAM_Buffer1+5
ExitIcon: rts
;-------------------------------------------------------------------------------------
DemoActionData:
.db $01, $80, $02, $81, $41, $80, $01
.db $42, $c2, $02, $80, $41, $c1, $41, $c1
.db $01, $c1, $01, $02, $80, $00
DemoTimingData:
.db $9b, $10, $18, $05, $2c, $20, $24
.db $15, $5a, $10, $20, $28, $30, $20, $10
.db $80, $20, $30, $30, $01, $ff, $00
DemoEngine:
ldx DemoAction ;load current demo action
lda DemoActionTimer ;load current action timer
bne DoAction ;if timer still counting down, skip
inx
inc DemoAction ;if expired, increment action, X, and
sec ;set carry by default for demo over
lda DemoTimingData-1,x ;get next timer
sta DemoActionTimer ;store as current timer
beq DemoOver ;if timer already at zero, skip
DoAction: lda DemoActionData-1,x ;get and perform action (current or next)
sta SavedJoypad1Bits
dec DemoActionTimer ;decrement action timer
clc ;clear carry if demo still going
DemoOver: rts
;-------------------------------------------------------------------------------------
VictoryMode:
jsr VictoryModeSubroutines ;run victory mode subroutines
lda OperMode_Task ;get current task of victory mode
beq AutoPlayer ;if on bridge collapse, skip enemy processing
ldx #$00
stx ObjectOffset ;otherwise reset enemy object offset
jsr EnemiesAndLoopsCore ;and run enemy code
AutoPlayer: jsr RelativePlayerPosition ;get player's relative coordinates
jmp PlayerGfxHandler ;draw the player, then leave
VictoryModeSubroutines:
lda OperMode_Task
jsr JumpEngine
.dw BridgeCollapse
.dw SetupVictoryMode
.dw PlayerVictoryWalk
.dw PrintVictoryMessages
.dw PlayerEndWorld
;-------------------------------------------------------------------------------------
SetupVictoryMode:
ldx ScreenRight_PageLoc ;get page location of right side of screen
inx ;increment to next page
stx DestinationPageLoc ;store here
lda #EndOfCastleMusic
sta EventMusicQueue ;play win castle music
jmp IncModeTask_B ;jump to set next major task in victory mode
;-------------------------------------------------------------------------------------
PlayerVictoryWalk:
ldy #$00 ;set value here to not walk player by default
sty VictoryWalkControl
lda Player_PageLoc ;get player's page location
cmp DestinationPageLoc ;compare with destination page location
bne PerformWalk ;if page locations don't match, branch
lda Player_X_Position ;otherwise get player's horizontal position
cmp #$60 ;compare with preset horizontal position
bcs DontWalk ;if still on other page, branch ahead
PerformWalk: inc VictoryWalkControl ;otherwise increment value and Y
iny ;note Y will be used to walk the player
DontWalk: tya ;put contents of Y in A and
jsr AutoControlPlayer ;use A to move player to the right or not
lda ScreenLeft_PageLoc ;check page location of left side of screen
cmp DestinationPageLoc ;against set value here
beq ExitVWalk ;branch if equal to change modes if necessary
lda ScrollFractional
clc ;do fixed point math on fractional part of scroll
adc #$80
sta ScrollFractional ;save fractional movement amount
lda #$01 ;set 1 pixel per frame
adc #$00 ;add carry from previous addition
tay ;use as scroll amount
jsr ScrollScreen ;do sub to scroll the screen
jsr UpdScrollVar ;do another sub to update screen and scroll variables
inc VictoryWalkControl ;increment value to stay in this routine
ExitVWalk: lda VictoryWalkControl ;load value set here
beq IncModeTask_A ;if zero, branch to change modes
rts ;otherwise leave
;-------------------------------------------------------------------------------------
PrintVictoryMessages:
lda SecondaryMsgCounter ;load secondary message counter
bne IncMsgCounter ;if set, branch to increment message counters
lda PrimaryMsgCounter ;otherwise load primary message counter
beq ThankPlayer ;if set to zero, branch to print first message
cmp #$09 ;if at 9 or above, branch elsewhere (this comparison
bcs IncMsgCounter ;is residual code, counter never reaches 9)
ldy WorldNumber ;check world number
cpy #World8
bne MRetainerMsg ;if not at world 8, skip to next part
cmp #$03 ;check primary message counter again
bcc IncMsgCounter ;if not at 3 yet (world 8 only), branch to increment
sbc #$01 ;otherwise subtract one
jmp ThankPlayer ;and skip to next part
MRetainerMsg: cmp #$02 ;check primary message counter
bcc IncMsgCounter ;if not at 2 yet (world 1-7 only), branch
ThankPlayer: tay ;put primary message counter into Y
bne SecondPartMsg ;if counter nonzero, skip this part, do not print first message
lda CurrentPlayer ;otherwise get player currently on the screen
beq EvalForMusic ;if mario, branch
iny ;otherwise increment Y once for luigi and
bne EvalForMusic ;do an unconditional branch to the same place
SecondPartMsg: iny ;increment Y to do world 8's message
lda WorldNumber
cmp #World8 ;check world number
beq EvalForMusic ;if at world 8, branch to next part
dey ;otherwise decrement Y for world 1-7's message
cpy #$04 ;if counter at 4 (world 1-7 only)
bcs SetEndTimer ;branch to set victory end timer
cpy #$03 ;if counter at 3 (world 1-7 only)
bcs IncMsgCounter ;branch to keep counting
EvalForMusic: cpy #$03 ;if counter not yet at 3 (world 8 only), branch
bne PrintMsg ;to print message only (note world 1-7 will only
lda #VictoryMusic ;reach this code if counter = 0, and will always branch)
sta EventMusicQueue ;otherwise load victory music first (world 8 only)
PrintMsg: tya ;put primary message counter in A
clc ;add $0c or 12 to counter thus giving an appropriate value,
adc #$0c ;($0c-$0d = first), ($0e = world 1-7's), ($0f-$12 = world 8's)
sta VRAM_Buffer_AddrCtrl ;write message counter to vram address controller
IncMsgCounter: lda SecondaryMsgCounter
clc
adc #$04 ;add four to secondary message counter
sta SecondaryMsgCounter
lda PrimaryMsgCounter
adc #$00 ;add carry to primary message counter
sta PrimaryMsgCounter
cmp #$07 ;check primary counter one more time
SetEndTimer: bcc ExitMsgs ;if not reached value yet, branch to leave
lda #$06
sta WorldEndTimer ;otherwise set world end timer
IncModeTask_A: inc OperMode_Task ;move onto next task in mode
ExitMsgs: rts ;leave
;-------------------------------------------------------------------------------------
PlayerEndWorld:
lda WorldEndTimer ;check to see if world end timer expired
bne EndExitOne ;branch to leave if not
ldy WorldNumber ;check world number
cpy #World8 ;if on world 8, player is done with game,
bcs EndChkBButton ;thus branch to read controller
lda #$00
sta AreaNumber ;otherwise initialize area number used as offset
sta LevelNumber ;and level number control to start at area 1
sta OperMode_Task ;initialize secondary mode of operation
inc WorldNumber ;increment world number to move onto the next world
jsr LoadAreaPointer ;get area address offset for the next area
inc FetchNewGameTimerFlag ;set flag to load game timer from header
lda #GameModeValue
sta OperMode ;set mode of operation to game mode
EndExitOne: rts ;and leave
EndChkBButton: lda SavedJoypad1Bits
ora SavedJoypad2Bits ;check to see if B button was pressed on
and #B_Button ;either controller
beq EndExitTwo ;branch to leave if not
lda #$01 ;otherwise set world selection flag
sta WorldSelectEnableFlag
lda #$ff ;remove onscreen player's lives
sta NumberofLives
jsr TerminateGame ;do sub to continue other player or end game
EndExitTwo: rts ;leave
;-------------------------------------------------------------------------------------
;data is used as tiles for numbers
;that appear when you defeat enemies
FloateyNumTileData:
.db $ff, $ff ;dummy
.db $f6, $fb ; "100"
.db $f7, $fb ; "200"
.db $f8, $fb ; "400"
.db $f9, $fb ; "500"
.db $fa, $fb ; "800"
.db $f6, $50 ; "1000"
.db $f7, $50 ; "2000"
.db $f8, $50 ; "4000"
.db $f9, $50 ; "5000"
.db $fa, $50 ; "8000"
.db $fd, $fe ; "1-UP"
;high nybble is digit number, low nybble is number to
;add to the digit of the player's score
ScoreUpdateData:
.db $ff ;dummy
.db $41, $42, $44, $45, $48
.db $31, $32, $34, $35, $38, $00
FloateyNumbersRoutine:
lda FloateyNum_Control,x ;load control for floatey number
beq EndExitOne ;if zero, branch to leave
cmp #$0b ;if less than $0b, branch
bcc ChkNumTimer
lda #$0b ;otherwise set to $0b, thus keeping
sta FloateyNum_Control,x ;it in range
ChkNumTimer: tay ;use as Y
lda FloateyNum_Timer,x ;check value here
bne DecNumTimer ;if nonzero, branch ahead
sta FloateyNum_Control,x ;initialize floatey number control and leave
rts
DecNumTimer: dec FloateyNum_Timer,x ;decrement value here
cmp #$2b ;if not reached a certain point, branch
bne ChkTallEnemy
cpy #$0b ;check offset for $0b
bne LoadNumTiles ;branch ahead if not found
inc NumberofLives ;give player one extra life (1-up)
lda #Sfx_ExtraLife
sta Square2SoundQueue ;and play the 1-up sound
LoadNumTiles: lda ScoreUpdateData,y ;load point value here
lsr ;move high nybble to low
lsr
lsr
lsr
tax ;use as X offset, essentially the digit
lda ScoreUpdateData,y ;load again and this time
and #%00001111 ;mask out the high nybble
sta DigitModifier,x ;store as amount to add to the digit
jsr AddToScore ;update the score accordingly
ChkTallEnemy: ldy Enemy_SprDataOffset,x ;get OAM data offset for enemy object
lda Enemy_ID,x ;get enemy object identifier
cmp #Spiny
beq FloateyPart ;branch if spiny
cmp #PiranhaPlant
beq FloateyPart ;branch if piranha plant
cmp #HammerBro
beq GetAltOffset ;branch elsewhere if hammer bro
cmp #GreyCheepCheep
beq FloateyPart ;branch if cheep-cheep of either color
cmp #RedCheepCheep
beq FloateyPart
cmp #TallEnemy
bcs GetAltOffset ;branch elsewhere if enemy object => $09
lda Enemy_State,x
cmp #$02 ;if enemy state defeated or otherwise
bcs FloateyPart ;$02 or greater, branch beyond this part
GetAltOffset: ldx SprDataOffset_Ctrl ;load some kind of control bit
ldy Alt_SprDataOffset,x ;get alternate OAM data offset
ldx ObjectOffset ;get enemy object offset again
FloateyPart: lda FloateyNum_Y_Pos,x ;get vertical coordinate for
cmp #$18 ;floatey number, if coordinate in the
bcc SetupNumSpr ;status bar, branch
sbc #$01
sta FloateyNum_Y_Pos,x ;otherwise subtract one and store as new
SetupNumSpr: lda FloateyNum_Y_Pos,x ;get vertical coordinate
sbc #$08 ;subtract eight and dump into the
jsr DumpTwoSpr ;left and right sprite's Y coordinates
lda FloateyNum_X_Pos,x ;get horizontal coordinate
sta Sprite_X_Position,y ;store into X coordinate of left sprite
clc
adc #$08 ;add eight pixels and store into X
sta Sprite_X_Position+4,y ;coordinate of right sprite
lda #$02
sta Sprite_Attributes,y ;set palette control in attribute bytes
sta Sprite_Attributes+4,y ;of left and right sprites
lda FloateyNum_Control,x
asl ;multiply our floatey number control by 2
tax ;and use as offset for look-up table
lda FloateyNumTileData,x
sta Sprite_Tilenumber,y ;display first half of number of points
lda FloateyNumTileData+1,x
sta Sprite_Tilenumber+4,y ;display the second half
ldx ObjectOffset ;get enemy object offset and leave
rts
;-------------------------------------------------------------------------------------
ScreenRoutines:
lda ScreenRoutineTask ;run one of the following subroutines
jsr JumpEngine
.dw InitScreen
.dw SetupIntermediate
.dw WriteTopStatusLine
.dw WriteBottomStatusLine
.dw DisplayTimeUp
.dw ResetSpritesAndScreenTimer
.dw DisplayIntermediate
.dw ResetSpritesAndScreenTimer
.dw AreaParserTaskControl
.dw GetAreaPalette
.dw GetBackgroundColor
.dw GetAlternatePalette1
.dw DrawTitleScreen
.dw ClearBuffersDrawIcon
.dw WriteTopScore
;-------------------------------------------------------------------------------------
InitScreen:
jsr MoveAllSpritesOffscreen ;initialize all sprites including sprite #0
jsr InitializeNameTables ;and erase both name and attribute tables
lda OperMode
beq NextSubtask ;if mode still 0, do not load
ldx #$03 ;into buffer pointer
jmp SetVRAMAddr_A
;-------------------------------------------------------------------------------------
SetupIntermediate:
lda BackgroundColorCtrl ;save current background color control
pha ;and player status to stack
lda PlayerStatus
pha
lda #$00 ;set background color to black
sta PlayerStatus ;and player status to not fiery
lda #$02 ;this is the ONLY time background color control
sta BackgroundColorCtrl ;is set to less than 4
jsr GetPlayerColors
pla ;we only execute this routine for
sta PlayerStatus ;the intermediate lives display
pla ;and once we're done, we return bg
sta BackgroundColorCtrl ;color ctrl and player status from stack
jmp IncSubtask ;then move onto the next task
;-------------------------------------------------------------------------------------
AreaPalette:
.db $01, $02, $03, $04
GetAreaPalette:
ldy AreaType ;select appropriate palette to load
ldx AreaPalette,y ;based on area type
SetVRAMAddr_A: stx VRAM_Buffer_AddrCtrl ;store offset into buffer control
NextSubtask: jmp IncSubtask ;move onto next task
;-------------------------------------------------------------------------------------
;$00 - used as temp counter in GetPlayerColors
BGColorCtrl_Addr:
.db $00, $09, $0a, $04
BackgroundColors:
.db $22, $22, $0f, $0f ;used by area type if bg color ctrl not set
.db $0f, $22, $0f, $0f ;used by background color control if set
PlayerColors:
.db $22, $16, $27, $18 ;mario's colors
.db $22, $30, $27, $19 ;luigi's colors
.db $22, $37, $27, $16 ;fiery (used by both)
GetBackgroundColor:
ldy BackgroundColorCtrl ;check background color control
beq NoBGColor ;if not set, increment task and fetch palette
lda BGColorCtrl_Addr-4,y ;put appropriate palette into vram
sta VRAM_Buffer_AddrCtrl ;note that if set to 5-7, $0301 will not be read
NoBGColor: inc ScreenRoutineTask ;increment to next subtask and plod on through
GetPlayerColors:
ldx VRAM_Buffer1_Offset ;get current buffer offset
ldy #$00
lda CurrentPlayer ;check which player is on the screen
beq ChkFiery
ldy #$04 ;load offset for luigi
ChkFiery: lda PlayerStatus ;check player status
cmp #$02
bne StartClrGet ;if fiery, load alternate offset for fiery player
ldy #$08
StartClrGet: lda #$03 ;do four colors
sta $00
ClrGetLoop: lda PlayerColors,y ;fetch player colors and store them
sta VRAM_Buffer1+3,x ;in the buffer
iny
inx
dec $00
bpl ClrGetLoop
ldx VRAM_Buffer1_Offset ;load original offset from before
ldy BackgroundColorCtrl ;if this value is four or greater, it will be set
bne SetBGColor ;therefore use it as offset to background color
ldy AreaType ;otherwise use area type bits from area offset as offset
SetBGColor: lda BackgroundColors,y ;to background color instead
sta VRAM_Buffer1+3,x
lda #$3f ;set for sprite palette address
sta VRAM_Buffer1,x ;save to buffer
lda #$10
sta VRAM_Buffer1+1,x
lda #$04 ;write length byte to buffer
sta VRAM_Buffer1+2,x
lda #$00 ;now the null terminator
sta VRAM_Buffer1+7,x
txa ;move the buffer pointer ahead 7 bytes
clc ;in case we want to write anything else later
adc #$07
SetVRAMOffset: sta VRAM_Buffer1_Offset ;store as new vram buffer offset
rts
;-------------------------------------------------------------------------------------
GetAlternatePalette1:
lda AreaStyle ;check for mushroom level style
cmp #$01
bne NoAltPal
lda #$0b ;if found, load appropriate palette
SetVRAMAddr_B: sta VRAM_Buffer_AddrCtrl
NoAltPal: jmp IncSubtask ;now onto the next task
;-------------------------------------------------------------------------------------
WriteTopStatusLine:
lda #$00 ;select main status bar
jsr WriteGameText ;output it
jmp IncSubtask ;onto the next task
;-------------------------------------------------------------------------------------
WriteBottomStatusLine:
jsr GetSBNybbles ;write player's score and coin tally to screen
ldx VRAM_Buffer1_Offset
lda #$20 ;write address for world-area number on screen
sta VRAM_Buffer1,x
lda #$73
sta VRAM_Buffer1+1,x
lda #$03 ;write length for it
sta VRAM_Buffer1+2,x
ldy WorldNumber ;first the world number
iny
tya
sta VRAM_Buffer1+3,x
lda #$28 ;next the dash
sta VRAM_Buffer1+4,x
ldy LevelNumber ;next the level number
iny ;increment for proper number display
tya
sta VRAM_Buffer1+5,x
lda #$00 ;put null terminator on
sta VRAM_Buffer1+6,x
txa ;move the buffer offset up by 6 bytes
clc
adc #$06
sta VRAM_Buffer1_Offset
jmp IncSubtask
;-------------------------------------------------------------------------------------
DisplayTimeUp:
lda GameTimerExpiredFlag ;if game timer not expired, increment task
beq NoTimeUp ;control 2 tasks forward, otherwise, stay here
lda #$00
sta GameTimerExpiredFlag ;reset timer expiration flag
lda #$02 ;output time-up screen to buffer
jmp OutputInter
NoTimeUp: inc ScreenRoutineTask ;increment control task 2 tasks forward
jmp IncSubtask
;-------------------------------------------------------------------------------------
DisplayIntermediate:
lda OperMode ;check primary mode of operation
beq NoInter ;if in title screen mode, skip this
cmp #GameOverModeValue ;are we in game over mode?
beq GameOverInter ;if so, proceed to display game over screen
lda AltEntranceControl ;otherwise check for mode of alternate entry
bne NoInter ;and branch if found
ldy AreaType ;check if we are on castle level
cpy #$03 ;and if so, branch (possibly residual)
beq PlayerInter
lda DisableIntermediate ;if this flag is set, skip intermediate lives display
bne NoInter ;and jump to specific task, otherwise
PlayerInter: jsr DrawPlayer_Intermediate ;put player in appropriate place for
lda #$01 ;lives display, then output lives display to buffer
OutputInter: jsr WriteGameText
jsr ResetScreenTimer
lda #$00
sta DisableScreenFlag ;reenable screen output
rts
GameOverInter: lda #$12 ;set screen timer
sta ScreenTimer
lda #$03 ;output game over screen to buffer
jsr WriteGameText
jmp IncModeTask_B
NoInter: lda #$08 ;set for specific task and leave
sta ScreenRoutineTask
rts
;-------------------------------------------------------------------------------------
AreaParserTaskControl:
inc DisableScreenFlag ;turn off screen
TaskLoop: jsr AreaParserTaskHandler ;render column set of current area
lda AreaParserTaskNum ;check number of tasks
bne TaskLoop ;if tasks still not all done, do another one
dec ColumnSets ;do we need to render more column sets?
bpl OutputCol
inc ScreenRoutineTask ;if not, move on to the next task
OutputCol: lda #$06 ;set vram buffer to output rendered column set
sta VRAM_Buffer_AddrCtrl ;on next NMI
rts
;-------------------------------------------------------------------------------------
;$00 - vram buffer address table low
;$01 - vram buffer address table high
DrawTitleScreen:
lda OperMode ;are we in title screen mode?
bne IncModeTask_B ;if not, exit
lda #>TitleScreenDataOffset ;load address $1ec0 into
sta PPU_ADDRESS ;the vram address register
lda #<TitleScreenDataOffset
sta PPU_ADDRESS
lda #$03 ;put address $0300 into
sta $01 ;the indirect at $00
ldy #$00
sty $00
lda PPU_DATA ;do one garbage read
OutputTScr: lda PPU_DATA ;get title screen from chr-rom
sta ($00),y ;store 256 bytes into buffer
iny
bne ChkHiByte ;if not past 256 bytes, do not increment
inc $01 ;otherwise increment high byte of indirect
ChkHiByte: lda $01 ;check high byte?
cmp #$04 ;at $0400?
bne OutputTScr ;if not, loop back and do another
cpy #$3a ;check if offset points past end of data
bcc OutputTScr ;if not, loop back and do another
lda #$05 ;set buffer transfer control to $0300,
jmp SetVRAMAddr_B ;increment task and exit
;-------------------------------------------------------------------------------------
ClearBuffersDrawIcon:
lda OperMode ;check game mode
bne IncModeTask_B ;if not title screen mode, leave
ldx #$00 ;otherwise, clear buffer space
TScrClear: sta VRAM_Buffer1-1,x
sta VRAM_Buffer1-1+$100,x
dex
bne TScrClear
jsr DrawMushroomIcon ;draw player select icon
IncSubtask: inc ScreenRoutineTask ;move onto next task
rts
;-------------------------------------------------------------------------------------
WriteTopScore:
lda #$fa ;run display routine to display top score on title
jsr UpdateNumber
IncModeTask_B: inc OperMode_Task ;move onto next mode
rts
;-------------------------------------------------------------------------------------
GameText:
TopStatusBarLine:
.db $20, $43, $05, $16, $0a, $1b, $12, $18 ; "MARIO"
.db $20, $52, $0b, $20, $18, $1b, $15, $0d ; "WORLD TIME"
.db $24, $24, $1d, $12, $16, $0e
.db $20, $68, $05, $00, $24, $24, $2e, $29 ; score trailing digit and coin display
.db $23, $c0, $7f, $aa ; attribute table data, clears name table 0 to palette 2
.db $23, $c2, $01, $ea ; attribute table data, used for coin icon in status bar
.db $ff ; end of data block
WorldLivesDisplay:
.db $21, $cd, $07, $24, $24 ; cross with spaces used on
.db $29, $24, $24, $24, $24 ; lives display
.db $21, $4b, $09, $20, $18 ; "WORLD - " used on lives display
.db $1b, $15, $0d, $24, $24, $28, $24
.db $22, $0c, $47, $24 ; possibly used to clear time up
.db $23, $dc, $01, $ba ; attribute table data for crown if more than 9 lives
.db $ff
TwoPlayerTimeUp:
.db $21, $cd, $05, $16, $0a, $1b, $12, $18 ; "MARIO"
OnePlayerTimeUp:
.db $22, $0c, $07, $1d, $12, $16, $0e, $24, $1e, $19 ; "TIME UP"
.db $ff
TwoPlayerGameOver:
.db $21, $cd, $05, $16, $0a, $1b, $12, $18 ; "MARIO"
OnePlayerGameOver:
.db $22, $0b, $09, $10, $0a, $16, $0e, $24 ; "GAME OVER"
.db $18, $1f, $0e, $1b
.db $ff
WarpZoneWelcome:
.db $25, $84, $15, $20, $0e, $15, $0c, $18, $16 ; "WELCOME TO WARP ZONE!"
.db $0e, $24, $1d, $18, $24, $20, $0a, $1b, $19
.db $24, $23, $18, $17, $0e, $2b
.db $26, $25, $01, $24 ; placeholder for left pipe
.db $26, $2d, $01, $24 ; placeholder for middle pipe
.db $26, $35, $01, $24 ; placeholder for right pipe
.db $27, $d9, $46, $aa ; attribute data
.db $27, $e1, $45, $aa
.db $ff
LuigiName:
.db $15, $1e, $12, $10, $12 ; "LUIGI", no address or length
WarpZoneNumbers:
.db $04, $03, $02, $00 ; warp zone numbers, note spaces on middle
.db $24, $05, $24, $00 ; zone, partly responsible for
.db $08, $07, $06, $00 ; the minus world
GameTextOffsets:
.db TopStatusBarLine-GameText, TopStatusBarLine-GameText
.db WorldLivesDisplay-GameText, WorldLivesDisplay-GameText
.db TwoPlayerTimeUp-GameText, OnePlayerTimeUp-GameText
.db TwoPlayerGameOver-GameText, OnePlayerGameOver-GameText
.db WarpZoneWelcome-GameText, WarpZoneWelcome-GameText
WriteGameText:
pha ;save text number to stack
asl
tay ;multiply by 2 and use as offset
cpy #$04 ;if set to do top status bar or world/lives display,
bcc LdGameText ;branch to use current offset as-is
cpy #$08 ;if set to do time-up or game over,
bcc Chk2Players ;branch to check players
ldy #$08 ;otherwise warp zone, therefore set offset
Chk2Players: lda NumberOfPlayers ;check for number of players
bne LdGameText ;if there are two, use current offset to also print name
iny ;otherwise increment offset by one to not print name
LdGameText: ldx GameTextOffsets,y ;get offset to message we want to print
ldy #$00
GameTextLoop: lda GameText,x ;load message data
cmp #$ff ;check for terminator
beq EndGameText ;branch to end text if found
sta VRAM_Buffer1,y ;otherwise write data to buffer
inx ;and increment increment
iny
bne GameTextLoop ;do this for 256 bytes if no terminator found
EndGameText: lda #$00 ;put null terminator at end
sta VRAM_Buffer1,y
pla ;pull original text number from stack
tax
cmp #$04 ;are we printing warp zone?
bcs PrintWarpZoneNumbers
dex ;are we printing the world/lives display?
bne CheckPlayerName ;if not, branch to check player's name
lda NumberofLives ;otherwise, check number of lives
clc ;and increment by one for display
adc #$01
cmp #10 ;more than 9 lives?
bcc PutLives
sbc #10 ;if so, subtract 10 and put a crown tile
ldy #$9f ;next to the difference...strange things happen if
sty VRAM_Buffer1+7 ;the number of lives exceeds 19
PutLives: sta VRAM_Buffer1+8
ldy WorldNumber ;write world and level numbers (incremented for display)
iny ;to the buffer in the spaces surrounding the dash
sty VRAM_Buffer1+19
ldy LevelNumber
iny
sty VRAM_Buffer1+21 ;we're done here
rts
CheckPlayerName:
lda NumberOfPlayers ;check number of players
beq ExitChkName ;if only 1 player, leave
lda CurrentPlayer ;load current player
dex ;check to see if current message number is for time up
bne ChkLuigi
ldy OperMode ;check for game over mode
cpy #GameOverModeValue
beq ChkLuigi
eor #%00000001 ;if not, must be time up, invert d0 to do other player
ChkLuigi: lsr
bcc ExitChkName ;if mario is current player, do not change the name
ldy #$04
NameLoop: lda LuigiName,y ;otherwise, replace "MARIO" with "LUIGI"
sta VRAM_Buffer1+3,y
dey
bpl NameLoop ;do this until each letter is replaced
ExitChkName: rts
PrintWarpZoneNumbers:
sbc #$04 ;subtract 4 and then shift to the left
asl ;twice to get proper warp zone number
asl ;offset
tax
ldy #$00
WarpNumLoop: lda WarpZoneNumbers,x ;print warp zone numbers into the
sta VRAM_Buffer1+27,y ;placeholders from earlier
inx
iny ;put a number in every fourth space
iny
iny
iny
cpy #$0c
bcc WarpNumLoop
lda #$2c ;load new buffer pointer at end of message
jmp SetVRAMOffset
;-------------------------------------------------------------------------------------
ResetSpritesAndScreenTimer:
lda ScreenTimer ;check if screen timer has expired
bne NoReset ;if not, branch to leave
jsr MoveAllSpritesOffscreen ;otherwise reset sprites now
ResetScreenTimer:
lda #$07 ;reset timer again
sta ScreenTimer
inc ScreenRoutineTask ;move onto next task
NoReset: rts
;-------------------------------------------------------------------------------------
;$00 - temp vram buffer offset
;$01 - temp metatile buffer offset
;$02 - temp metatile graphics table offset
;$03 - used to store attribute bits
;$04 - used to determine attribute table row
;$05 - used to determine attribute table column
;$06 - metatile graphics table address low
;$07 - metatile graphics table address high
RenderAreaGraphics:
lda CurrentColumnPos ;store LSB of where we're at
and #$01
sta $05
ldy VRAM_Buffer2_Offset ;store vram buffer offset
sty $00
lda CurrentNTAddr_Low ;get current name table address we're supposed to render
sta VRAM_Buffer2+1,y
lda CurrentNTAddr_High
sta VRAM_Buffer2,y
lda #$9a ;store length byte of 26 here with d7 set
sta VRAM_Buffer2+2,y ;to increment by 32 (in columns)
lda #$00 ;init attribute row
sta $04
tax
DrawMTLoop: stx $01 ;store init value of 0 or incremented offset for buffer
lda MetatileBuffer,x ;get first metatile number, and mask out all but 2 MSB
and #%11000000
sta $03 ;store attribute table bits here
asl ;note that metatile format is:
rol ;%xx000000 - attribute table bits,
rol ;%00xxxxxx - metatile number
tay ;rotate bits to d1-d0 and use as offset here
lda MetatileGraphics_Low,y ;get address to graphics table from here
sta $06
lda MetatileGraphics_High,y
sta $07
lda MetatileBuffer,x ;get metatile number again
asl ;multiply by 4 and use as tile offset
asl
sta $02
lda AreaParserTaskNum ;get current task number for level processing and
and #%00000001 ;mask out all but LSB, then invert LSB, multiply by 2
eor #%00000001 ;to get the correct column position in the metatile,
asl ;then add to the tile offset so we can draw either side
adc $02 ;of the metatiles
tay
ldx $00 ;use vram buffer offset from before as X
lda ($06),y
sta VRAM_Buffer2+3,x ;get first tile number (top left or top right) and store
iny
lda ($06),y ;now get the second (bottom left or bottom right) and store
sta VRAM_Buffer2+4,x
ldy $04 ;get current attribute row
lda $05 ;get LSB of current column where we're at, and
bne RightCheck ;branch if set (clear = left attrib, set = right)
lda $01 ;get current row we're rendering
lsr ;branch if LSB set (clear = top left, set = bottom left)
bcs LLeft
rol $03 ;rotate attribute bits 3 to the left
rol $03 ;thus in d1-d0, for upper left square
rol $03
jmp SetAttrib
RightCheck: lda $01 ;get LSB of current row we're rendering
lsr ;branch if set (clear = top right, set = bottom right)
bcs NextMTRow
lsr $03 ;shift attribute bits 4 to the right
lsr $03 ;thus in d3-d2, for upper right square
lsr $03
lsr $03
jmp SetAttrib
LLeft: lsr $03 ;shift attribute bits 2 to the right
lsr $03 ;thus in d5-d4 for lower left square
NextMTRow: inc $04 ;move onto next attribute row
SetAttrib: lda AttributeBuffer,y ;get previously saved bits from before
ora $03 ;if any, and put new bits, if any, onto
sta AttributeBuffer,y ;the old, and store
inc $00 ;increment vram buffer offset by 2
inc $00
ldx $01 ;get current gfx buffer row, and check for
inx ;the bottom of the screen
cpx #$0d
bcc DrawMTLoop ;if not there yet, loop back
ldy $00 ;get current vram buffer offset, increment by 3
iny ;(for name table address and length bytes)
iny
iny
lda #$00
sta VRAM_Buffer2,y ;put null terminator at end of data for name table
sty VRAM_Buffer2_Offset ;store new buffer offset
inc CurrentNTAddr_Low ;increment name table address low
lda CurrentNTAddr_Low ;check current low byte
and #%00011111 ;if no wraparound, just skip this part
bne ExitDrawM
lda #$80 ;if wraparound occurs, make sure low byte stays
sta CurrentNTAddr_Low ;just under the status bar
lda CurrentNTAddr_High ;and then invert d2 of the name table address high
eor #%00000100 ;to move onto the next appropriate name table
sta CurrentNTAddr_High
ExitDrawM: jmp SetVRAMCtrl ;jump to set buffer to $0341 and leave
;-------------------------------------------------------------------------------------
;$00 - temp attribute table address high (big endian order this time!)
;$01 - temp attribute table address low
RenderAttributeTables:
lda CurrentNTAddr_Low ;get low byte of next name table address
and #%00011111 ;to be written to, mask out all but 5 LSB,
sec ;subtract four
sbc #$04
and #%00011111 ;mask out bits again and store
sta $01
lda CurrentNTAddr_High ;get high byte and branch if borrow not set
bcs SetATHigh
eor #%00000100 ;otherwise invert d2
SetATHigh: and #%00000100 ;mask out all other bits
ora #$23 ;add $2300 to the high byte and store
sta $00
lda $01 ;get low byte - 4, divide by 4, add offset for
lsr ;attribute table and store
lsr
adc #$c0 ;we should now have the appropriate block of
sta $01 ;attribute table in our temp address
ldx #$00
ldy VRAM_Buffer2_Offset ;get buffer offset
AttribLoop: lda $00
sta VRAM_Buffer2,y ;store high byte of attribute table address
lda $01
clc ;get low byte, add 8 because we want to start
adc #$08 ;below the status bar, and store
sta VRAM_Buffer2+1,y
sta $01 ;also store in temp again
lda AttributeBuffer,x ;fetch current attribute table byte and store
sta VRAM_Buffer2+3,y ;in the buffer
lda #$01
sta VRAM_Buffer2+2,y ;store length of 1 in buffer
lsr
sta AttributeBuffer,x ;clear current byte in attribute buffer
iny ;increment buffer offset by 4 bytes
iny
iny
iny
inx ;increment attribute offset and check to see
cpx #$07 ;if we're at the end yet
bcc AttribLoop
sta VRAM_Buffer2,y ;put null terminator at the end
sty VRAM_Buffer2_Offset ;store offset in case we want to do any more
SetVRAMCtrl: lda #$06
sta VRAM_Buffer_AddrCtrl ;set buffer to $0341 and leave
rts
;-------------------------------------------------------------------------------------
;$00 - used as temporary counter in ColorRotation
ColorRotatePalette:
.db $27, $27, $27, $17, $07, $17
BlankPalette:
.db $3f, $0c, $04, $ff, $ff, $ff, $ff, $00
;used based on area type
Palette3Data:
.db $0f, $07, $12, $0f
.db $0f, $07, $17, $0f
.db $0f, $07, $17, $1c
.db $0f, $07, $17, $00
ColorRotation:
lda FrameCounter ;get frame counter
and #$07 ;mask out all but three LSB
bne ExitColorRot ;branch if not set to zero to do this every eighth frame
ldx VRAM_Buffer1_Offset ;check vram buffer offset
cpx #$31
bcs ExitColorRot ;if offset over 48 bytes, branch to leave
tay ;otherwise use frame counter's 3 LSB as offset here
GetBlankPal: lda BlankPalette,y ;get blank palette for palette 3
sta VRAM_Buffer1,x ;store it in the vram buffer
inx ;increment offsets
iny
cpy #$08
bcc GetBlankPal ;do this until all bytes are copied
ldx VRAM_Buffer1_Offset ;get current vram buffer offset
lda #$03
sta $00 ;set counter here
lda AreaType ;get area type
asl ;multiply by 4 to get proper offset
asl
tay ;save as offset here
GetAreaPal: lda Palette3Data,y ;fetch palette to be written based on area type
sta VRAM_Buffer1+3,x ;store it to overwrite blank palette in vram buffer
iny
inx
dec $00 ;decrement counter
bpl GetAreaPal ;do this until the palette is all copied
ldx VRAM_Buffer1_Offset ;get current vram buffer offset
ldy ColorRotateOffset ;get color cycling offset
lda ColorRotatePalette,y
sta VRAM_Buffer1+4,x ;get and store current color in second slot of palette
lda VRAM_Buffer1_Offset
clc ;add seven bytes to vram buffer offset
adc #$07
sta VRAM_Buffer1_Offset
inc ColorRotateOffset ;increment color cycling offset
lda ColorRotateOffset
cmp #$06 ;check to see if it's still in range
bcc ExitColorRot ;if so, branch to leave
lda #$00
sta ColorRotateOffset ;otherwise, init to keep it in range
ExitColorRot: rts ;leave
;-------------------------------------------------------------------------------------
;$00 - temp store for offset control bit
;$01 - temp vram buffer offset
;$02 - temp store for vertical high nybble in block buffer routine
;$03 - temp adder for high byte of name table address
;$04, $05 - name table address low/high
;$06, $07 - block buffer address low/high
BlockGfxData:
.db $45, $45, $47, $47
.db $47, $47, $47, $47
.db $57, $58, $59, $5a
.db $24, $24, $24, $24
.db $26, $26, $26, $26
RemoveCoin_Axe:
ldy #$41 ;set low byte so offset points to $0341
lda #$03 ;load offset for default blank metatile
ldx AreaType ;check area type
bne WriteBlankMT ;if not water type, use offset
lda #$04 ;otherwise load offset for blank metatile used in water
WriteBlankMT: jsr PutBlockMetatile ;do a sub to write blank metatile to vram buffer
lda #$06
sta VRAM_Buffer_AddrCtrl ;set vram address controller to $0341 and leave
rts
ReplaceBlockMetatile:
jsr WriteBlockMetatile ;write metatile to vram buffer to replace block object
inc Block_ResidualCounter ;increment unused counter (residual code)
dec Block_RepFlag,x ;decrement flag (residual code)
rts ;leave
DestroyBlockMetatile:
lda #$00 ;force blank metatile if branched/jumped to this point
WriteBlockMetatile:
ldy #$03 ;load offset for blank metatile
cmp #$00 ;check contents of A for blank metatile
beq UseBOffset ;branch if found (unconditional if branched from 8a6b)
ldy #$00 ;load offset for brick metatile w/ line
cmp #$58
beq UseBOffset ;use offset if metatile is brick with coins (w/ line)
cmp #$51
beq UseBOffset ;use offset if metatile is breakable brick w/ line
iny ;increment offset for brick metatile w/o line
cmp #$5d
beq UseBOffset ;use offset if metatile is brick with coins (w/o line)
cmp #$52
beq UseBOffset ;use offset if metatile is breakable brick w/o line
iny ;if any other metatile, increment offset for empty block
UseBOffset: tya ;put Y in A
ldy VRAM_Buffer1_Offset ;get vram buffer offset
iny ;move onto next byte
jsr PutBlockMetatile ;get appropriate block data and write to vram buffer
MoveVOffset: dey ;decrement vram buffer offset
tya ;add 10 bytes to it
clc
adc #10
jmp SetVRAMOffset ;branch to store as new vram buffer offset
PutBlockMetatile:
stx $00 ;store control bit from SprDataOffset_Ctrl
sty $01 ;store vram buffer offset for next byte
asl
asl ;multiply A by four and use as X
tax
ldy #$20 ;load high byte for name table 0
lda $06 ;get low byte of block buffer pointer
cmp #$d0 ;check to see if we're on odd-page block buffer
bcc SaveHAdder ;if not, use current high byte
ldy #$24 ;otherwise load high byte for name table 1
SaveHAdder: sty $03 ;save high byte here
and #$0f ;mask out high nybble of block buffer pointer
asl ;multiply by 2 to get appropriate name table low byte
sta $04 ;and then store it here
lda #$00
sta $05 ;initialize temp high byte
lda $02 ;get vertical high nybble offset used in block buffer routine
clc
adc #$20 ;add 32 pixels for the status bar
asl
rol $05 ;shift and rotate d7 onto d0 and d6 into carry
asl
rol $05 ;shift and rotate d6 onto d0 and d5 into carry
adc $04 ;add low byte of name table and carry to vertical high nybble
sta $04 ;and store here
lda $05 ;get whatever was in d7 and d6 of vertical high nybble
adc #$00 ;add carry
clc
adc $03 ;then add high byte of name table
sta $05 ;store here
ldy $01 ;get vram buffer offset to be used
RemBridge: lda BlockGfxData,x ;write top left and top right
sta VRAM_Buffer1+2,y ;tile numbers into first spot
lda BlockGfxData+1,x
sta VRAM_Buffer1+3,y
lda BlockGfxData+2,x ;write bottom left and bottom
sta VRAM_Buffer1+7,y ;right tiles numbers into
lda BlockGfxData+3,x ;second spot
sta VRAM_Buffer1+8,y
lda $04
sta VRAM_Buffer1,y ;write low byte of name table
clc ;into first slot as read
adc #$20 ;add 32 bytes to value
sta VRAM_Buffer1+5,y ;write low byte of name table
lda $05 ;plus 32 bytes into second slot
sta VRAM_Buffer1-1,y ;write high byte of name
sta VRAM_Buffer1+4,y ;table address to both slots
lda #$02
sta VRAM_Buffer1+1,y ;put length of 2 in
sta VRAM_Buffer1+6,y ;both slots
lda #$00
sta VRAM_Buffer1+9,y ;put null terminator at end
ldx $00 ;get offset control bit here
rts ;and leave
;-------------------------------------------------------------------------------------
;METATILE GRAPHICS TABLE
MetatileGraphics_Low:
.db <Palette0_MTiles, <Palette1_MTiles, <Palette2_MTiles, <Palette3_MTiles
MetatileGraphics_High:
.db >Palette0_MTiles, >Palette1_MTiles, >Palette2_MTiles, >Palette3_MTiles
Palette0_MTiles:
.db $24, $24, $24, $24 ;blank
.db $27, $27, $27, $27 ;black metatile
.db $24, $24, $24, $35 ;bush left
.db $36, $25, $37, $25 ;bush middle
.db $24, $38, $24, $24 ;bush right
.db $24, $30, $30, $26 ;mountain left
.db $26, $26, $34, $26 ;mountain left bottom/middle center
.db $24, $31, $24, $32 ;mountain middle top
.db $33, $26, $24, $33 ;mountain right
.db $34, $26, $26, $26 ;mountain right bottom
.db $26, $26, $26, $26 ;mountain middle bottom
.db $24, $c0, $24, $c0 ;bridge guardrail
.db $24, $7f, $7f, $24 ;chain
.db $b8, $ba, $b9, $bb ;tall tree top, top half
.db $b8, $bc, $b9, $bd ;short tree top
.db $ba, $bc, $bb, $bd ;tall tree top, bottom half
.db $60, $64, $61, $65 ;warp pipe end left, points up
.db $62, $66, $63, $67 ;warp pipe end right, points up
.db $60, $64, $61, $65 ;decoration pipe end left, points up
.db $62, $66, $63, $67 ;decoration pipe end right, points up
.db $68, $68, $69, $69 ;pipe shaft left
.db $26, $26, $6a, $6a ;pipe shaft right
.db $4b, $4c, $4d, $4e ;tree ledge left edge
.db $4d, $4f, $4d, $4f ;tree ledge middle
.db $4d, $4e, $50, $51 ;tree ledge right edge
.db $6b, $70, $2c, $2d ;mushroom left edge
.db $6c, $71, $6d, $72 ;mushroom middle
.db $6e, $73, $6f, $74 ;mushroom right edge
.db $86, $8a, $87, $8b ;sideways pipe end top
.db $88, $8c, $88, $8c ;sideways pipe shaft top
.db $89, $8d, $69, $69 ;sideways pipe joint top
.db $8e, $91, $8f, $92 ;sideways pipe end bottom
.db $26, $93, $26, $93 ;sideways pipe shaft bottom
.db $90, $94, $69, $69 ;sideways pipe joint bottom
.db $a4, $e9, $ea, $eb ;seaplant
.db $24, $24, $24, $24 ;blank, used on bricks or blocks that are hit
.db $24, $2f, $24, $3d ;flagpole ball
.db $a2, $a2, $a3, $a3 ;flagpole shaft
.db $24, $24, $24, $24 ;blank, used in conjunction with vines
Palette1_MTiles:
.db $a2, $a2, $a3, $a3 ;vertical rope
.db $99, $24, $99, $24 ;horizontal rope
.db $24, $a2, $3e, $3f ;left pulley
.db $5b, $5c, $24, $a3 ;right pulley
.db $24, $24, $24, $24 ;blank used for balance rope
.db $9d, $47, $9e, $47 ;castle top
.db $47, $47, $27, $27 ;castle window left
.db $47, $47, $47, $47 ;castle brick wall
.db $27, $27, $47, $47 ;castle window right
.db $a9, $47, $aa, $47 ;castle top w/ brick
.db $9b, $27, $9c, $27 ;entrance top
.db $27, $27, $27, $27 ;entrance bottom
.db $52, $52, $52, $52 ;green ledge stump
.db $80, $a0, $81, $a1 ;fence
.db $be, $be, $bf, $bf ;tree trunk
.db $75, $ba, $76, $bb ;mushroom stump top
.db $ba, $ba, $bb, $bb ;mushroom stump bottom
.db $45, $47, $45, $47 ;breakable brick w/ line
.db $47, $47, $47, $47 ;breakable brick
.db $45, $47, $45, $47 ;breakable brick (not used)
.db $b4, $b6, $b5, $b7 ;cracked rock terrain
.db $45, $47, $45, $47 ;brick with line (power-up)
.db $45, $47, $45, $47 ;brick with line (vine)
.db $45, $47, $45, $47 ;brick with line (star)
.db $45, $47, $45, $47 ;brick with line (coins)
.db $45, $47, $45, $47 ;brick with line (1-up)
.db $47, $47, $47, $47 ;brick (power-up)
.db $47, $47, $47, $47 ;brick (vine)
.db $47, $47, $47, $47 ;brick (star)
.db $47, $47, $47, $47 ;brick (coins)
.db $47, $47, $47, $47 ;brick (1-up)
.db $24, $24, $24, $24 ;hidden block (1 coin)
.db $24, $24, $24, $24 ;hidden block (1-up)
.db $ab, $ac, $ad, $ae ;solid block (3-d block)
.db $5d, $5e, $5d, $5e ;solid block (white wall)
.db $c1, $24, $c1, $24 ;bridge
.db $c6, $c8, $c7, $c9 ;bullet bill cannon barrel
.db $ca, $cc, $cb, $cd ;bullet bill cannon top
.db $2a, $2a, $40, $40 ;bullet bill cannon bottom
.db $24, $24, $24, $24 ;blank used for jumpspring
.db $24, $47, $24, $47 ;half brick used for jumpspring
.db $82, $83, $84, $85 ;solid block (water level, green rock)
.db $24, $47, $24, $47 ;half brick (???)
.db $86, $8a, $87, $8b ;water pipe top
.db $8e, $91, $8f, $92 ;water pipe bottom
.db $24, $2f, $24, $3d ;flag ball (residual object)
Palette2_MTiles:
.db $24, $24, $24, $35 ;cloud left
.db $36, $25, $37, $25 ;cloud middle
.db $24, $38, $24, $24 ;cloud right
.db $24, $24, $39, $24 ;cloud bottom left
.db $3a, $24, $3b, $24 ;cloud bottom middle
.db $3c, $24, $24, $24 ;cloud bottom right
.db $41, $26, $41, $26 ;water/lava top
.db $26, $26, $26, $26 ;water/lava
.db $b0, $b1, $b2, $b3 ;cloud level terrain
.db $77, $79, $77, $79 ;bowser's bridge
Palette3_MTiles:
.db $53, $55, $54, $56 ;question block (coin)
.db $53, $55, $54, $56 ;question block (power-up)
.db $a5, $a7, $a6, $a8 ;coin
.db $c2, $c4, $c3, $c5 ;underwater coin
.db $57, $59, $58, $5a ;empty block
.db $7b, $7d, $7c, $7e ;axe
;-------------------------------------------------------------------------------------
;VRAM BUFFER DATA FOR LOCATIONS IN PRG-ROM
WaterPaletteData:
.db $3f, $00, $20
.db $0f, $15, $12, $25
.db $0f, $3a, $1a, $0f
.db $0f, $30, $12, $0f
.db $0f, $27, $12, $0f
.db $22, $16, $27, $18
.db $0f, $10, $30, $27
.db $0f, $16, $30, $27
.db $0f, $0f, $30, $10
.db $00
GroundPaletteData:
.db $3f, $00, $20
.db $0f, $29, $1a, $0f
.db $0f, $36, $17, $0f
.db $0f, $30, $21, $0f
.db $0f, $27, $17, $0f
.db $0f, $16, $27, $18
.db $0f, $1a, $30, $27
.db $0f, $16, $30, $27
.db $0f, $0f, $36, $17
.db $00
UndergroundPaletteData:
.db $3f, $00, $20
.db $0f, $29, $1a, $09
.db $0f, $3c, $1c, $0f
.db $0f, $30, $21, $1c
.db $0f, $27, $17, $1c
.db $0f, $16, $27, $18
.db $0f, $1c, $36, $17
.db $0f, $16, $30, $27
.db $0f, $0c, $3c, $1c
.db $00
CastlePaletteData:
.db $3f, $00, $20
.db $0f, $30, $10, $00
.db $0f, $30, $10, $00
.db $0f, $30, $16, $00
.db $0f, $27, $17, $00
.db $0f, $16, $27, $18
.db $0f, $1c, $36, $17
.db $0f, $16, $30, $27
.db $0f, $00, $30, $10
.db $00
DaySnowPaletteData:
.db $3f, $00, $04
.db $22, $30, $00, $10
.db $00
NightSnowPaletteData:
.db $3f, $00, $04
.db $0f, $30, $00, $10
.db $00
MushroomPaletteData:
.db $3f, $00, $04
.db $22, $27, $16, $0f
.db $00
BowserPaletteData:
.db $3f, $14, $04
.db $0f, $1a, $30, $27
.db $00
MarioThanksMessage:
;"THANK YOU MARIO!"
.db $25, $48, $10
.db $1d, $11, $0a, $17, $14, $24
.db $22, $18, $1e, $24
.db $16, $0a, $1b, $12, $18, $2b
.db $00
LuigiThanksMessage:
;"THANK YOU LUIGI!"
.db $25, $48, $10
.db $1d, $11, $0a, $17, $14, $24
.db $22, $18, $1e, $24
.db $15, $1e, $12, $10, $12, $2b
.db $00
MushroomRetainerSaved:
;"BUT OUR PRINCESS IS IN"
.db $25, $c5, $16
.db $0b, $1e, $1d, $24, $18, $1e, $1b, $24
.db $19, $1b, $12, $17, $0c, $0e, $1c, $1c, $24
.db $12, $1c, $24, $12, $17
;"ANOTHER CASTLE!"
.db $26, $05, $0f
.db $0a, $17, $18, $1d, $11, $0e, $1b, $24
.db $0c, $0a, $1c, $1d, $15, $0e, $2b, $00
PrincessSaved1:
;"YOUR QUEST IS OVER."
.db $25, $a7, $13
.db $22, $18, $1e, $1b, $24
.db $1a, $1e, $0e, $1c, $1d, $24
.db $12, $1c, $24, $18, $1f, $0e, $1b, $af
.db $00
PrincessSaved2:
;"WE PRESENT YOU A NEW QUEST."
.db $25, $e3, $1b
.db $20, $0e, $24
.db $19, $1b, $0e, $1c, $0e, $17, $1d, $24
.db $22, $18, $1e, $24, $0a, $24, $17, $0e, $20, $24
.db $1a, $1e, $0e, $1c, $1d, $af
.db $00
WorldSelectMessage1:
;"PUSH BUTTON B"
.db $26, $4a, $0d
.db $19, $1e, $1c, $11, $24
.db $0b, $1e, $1d, $1d, $18, $17, $24, $0b
.db $00
WorldSelectMessage2:
;"TO SELECT A WORLD"
.db $26, $88, $11
.db $1d, $18, $24, $1c, $0e, $15, $0e, $0c, $1d, $24
.db $0a, $24, $20, $18, $1b, $15, $0d
.db $00
;-------------------------------------------------------------------------------------
;$04 - address low to jump address
;$05 - address high to jump address
;$06 - jump address low
;$07 - jump address high
JumpEngine:
asl ;shift bit from contents of A
tay
pla ;pull saved return address from stack
sta $04 ;save to indirect
pla
sta $05
iny
lda ($04),y ;load pointer from indirect
sta $06 ;note that if an RTS is performed in next routine
iny ;it will return to the execution before the sub
lda ($04),y ;that called this routine
sta $07
jmp ($06) ;jump to the address we loaded
;-------------------------------------------------------------------------------------
InitializeNameTables:
lda PPU_STATUS ;reset flip-flop
lda Mirror_PPU_CTRL_REG1 ;load mirror of ppu reg $2000
ora #%00010000 ;set sprites for first 4k and background for second 4k
and #%11110000 ;clear rest of lower nybble, leave higher alone
jsr WritePPUReg1
lda #$24 ;set vram address to start of name table 1
jsr WriteNTAddr
lda #$20 ;and then set it to name table 0
WriteNTAddr: sta PPU_ADDRESS
lda #$00
sta PPU_ADDRESS
ldx #$04 ;clear name table with blank tile #24
ldy #$c0
lda #$24
InitNTLoop: sta PPU_DATA ;count out exactly 768 tiles
dey
bne InitNTLoop
dex
bne InitNTLoop
ldy #64 ;now to clear the attribute table (with zero this time)
txa
sta VRAM_Buffer1_Offset ;init vram buffer 1 offset
sta VRAM_Buffer1 ;init vram buffer 1
InitATLoop: sta PPU_DATA
dey
bne InitATLoop
sta HorizontalScroll ;reset scroll variables
sta VerticalScroll
jmp InitScroll ;initialize scroll registers to zero
;-------------------------------------------------------------------------------------
;$00 - temp joypad bit
ReadJoypads:
lda #$01 ;reset and clear strobe of joypad ports
sta JOYPAD_PORT
lsr
tax ;start with joypad 1's port
sta JOYPAD_PORT
jsr ReadPortBits
inx ;increment for joypad 2's port
ReadPortBits: ldy #$08
PortLoop: pha ;push previous bit onto stack
lda JOYPAD_PORT,x ;read current bit on joypad port
sta $00 ;check d1 and d0 of port output
lsr ;this is necessary on the old
ora $00 ;famicom systems in japan
lsr
pla ;read bits from stack
rol ;rotate bit from carry flag
dey
bne PortLoop ;count down bits left
sta SavedJoypadBits,x ;save controller status here always
pha
and #%00110000 ;check for select or start
and JoypadBitMask,x ;if neither saved state nor current state
beq Save8Bits ;have any of these two set, branch
pla
and #%11001111 ;otherwise store without select
sta SavedJoypadBits,x ;or start bits and leave
rts
Save8Bits: pla
sta JoypadBitMask,x ;save with all bits in another place and leave
rts
;-------------------------------------------------------------------------------------
;$00 - vram buffer address table low
;$01 - vram buffer address table high
WriteBufferToScreen:
sta PPU_ADDRESS ;store high byte of vram address
iny
lda ($00),y ;load next byte (second)
sta PPU_ADDRESS ;store low byte of vram address
iny
lda ($00),y ;load next byte (third)
asl ;shift to left and save in stack
pha
lda Mirror_PPU_CTRL_REG1 ;load mirror of $2000,
ora #%00000100 ;set ppu to increment by 32 by default
bcs SetupWrites ;if d7 of third byte was clear, ppu will
and #%11111011 ;only increment by 1
SetupWrites: jsr WritePPUReg1 ;write to register
pla ;pull from stack and shift to left again
asl
bcc GetLength ;if d6 of third byte was clear, do not repeat byte
ora #%00000010 ;otherwise set d1 and increment Y
iny
GetLength: lsr ;shift back to the right to get proper length
lsr ;note that d1 will now be in carry
tax
OutputToVRAM: bcs RepeatByte ;if carry set, repeat loading the same byte
iny ;otherwise increment Y to load next byte
RepeatByte: lda ($00),y ;load more data from buffer and write to vram
sta PPU_DATA
dex ;done writing?
bne OutputToVRAM
sec
tya
adc $00 ;add end length plus one to the indirect at $00
sta $00 ;to allow this routine to read another set of updates
lda #$00
adc $01
sta $01
lda #$3f ;sets vram address to $3f00
sta PPU_ADDRESS
lda #$00
sta PPU_ADDRESS
sta PPU_ADDRESS ;then reinitializes it for some reason
sta PPU_ADDRESS
UpdateScreen: ldx PPU_STATUS ;reset flip-flop
ldy #$00 ;load first byte from indirect as a pointer
lda ($00),y
bne WriteBufferToScreen ;if byte is zero we have no further updates to make here
InitScroll: sta PPU_SCROLL_REG ;store contents of A into scroll registers
sta PPU_SCROLL_REG ;and end whatever subroutine led us here
rts
;-------------------------------------------------------------------------------------
WritePPUReg1:
sta PPU_CTRL_REG1 ;write contents of A to PPU register 1
sta Mirror_PPU_CTRL_REG1 ;and its mirror
rts
;-------------------------------------------------------------------------------------
;$00 - used to store status bar nybbles
;$02 - used as temp vram offset
;$03 - used to store length of status bar number
;status bar name table offset and length data
StatusBarData:
.db $f0, $06 ; top score display on title screen
.db $62, $06 ; player score
.db $62, $06
.db $6d, $02 ; coin tally
.db $6d, $02
.db $7a, $03 ; game timer
StatusBarOffset:
.db $06, $0c, $12, $18, $1e, $24
PrintStatusBarNumbers:
sta $00 ;store player-specific offset
jsr OutputNumbers ;use first nybble to print the coin display
lda $00 ;move high nybble to low
lsr ;and print to score display
lsr
lsr
lsr
OutputNumbers:
clc ;add 1 to low nybble
adc #$01
and #%00001111 ;mask out high nybble
cmp #$06
bcs ExitOutputN
pha ;save incremented value to stack for now and
asl ;shift to left and use as offset
tay
ldx VRAM_Buffer1_Offset ;get current buffer pointer
lda #$20 ;put at top of screen by default
cpy #$00 ;are we writing top score on title screen?
bne SetupNums
lda #$22 ;if so, put further down on the screen
SetupNums: sta VRAM_Buffer1,x
lda StatusBarData,y ;write low vram address and length of thing
sta VRAM_Buffer1+1,x ;we're printing to the buffer
lda StatusBarData+1,y
sta VRAM_Buffer1+2,x
sta $03 ;save length byte in counter
stx $02 ;and buffer pointer elsewhere for now
pla ;pull original incremented value from stack
tax
lda StatusBarOffset,x ;load offset to value we want to write
sec
sbc StatusBarData+1,y ;subtract from length byte we read before
tay ;use value as offset to display digits
ldx $02
DigitPLoop: lda DisplayDigits,y ;write digits to the buffer
sta VRAM_Buffer1+3,x
inx
iny
dec $03 ;do this until all the digits are written
bne DigitPLoop
lda #$00 ;put null terminator at end
sta VRAM_Buffer1+3,x
inx ;increment buffer pointer by 3
inx
inx
stx VRAM_Buffer1_Offset ;store it in case we want to use it again
ExitOutputN: rts
;-------------------------------------------------------------------------------------
DigitsMathRoutine:
lda OperMode ;check mode of operation
cmp #TitleScreenModeValue
beq EraseDMods ;if in title screen mode, branch to lock score
ldx #$05
AddModLoop: lda DigitModifier,x ;load digit amount to increment
clc
adc DisplayDigits,y ;add to current digit
bmi BorrowOne ;if result is a negative number, branch to subtract
cmp #10
bcs CarryOne ;if digit greater than $09, branch to add
StoreNewD: sta DisplayDigits,y ;store as new score or game timer digit
dey ;move onto next digits in score or game timer
dex ;and digit amounts to increment
bpl AddModLoop ;loop back if we're not done yet
EraseDMods: lda #$00 ;store zero here
ldx #$06 ;start with the last digit
EraseMLoop: sta DigitModifier-1,x ;initialize the digit amounts to increment
dex
bpl EraseMLoop ;do this until they're all reset, then leave
rts
BorrowOne: dec DigitModifier-1,x ;decrement the previous digit, then put $09 in
lda #$09 ;the game timer digit we're currently on to "borrow
bne StoreNewD ;the one", then do an unconditional branch back
CarryOne: sec ;subtract ten from our digit to make it a
sbc #10 ;proper BCD number, then increment the digit
inc DigitModifier-1,x ;preceding current digit to "carry the one" properly
jmp StoreNewD ;go back to just after we branched here
;-------------------------------------------------------------------------------------
UpdateTopScore:
ldx #$05 ;start with mario's score
jsr TopScoreCheck
ldx #$0b ;now do luigi's score
TopScoreCheck:
ldy #$05 ;start with the lowest digit
sec
GetScoreDiff: lda PlayerScoreDisplay,x ;subtract each player digit from each high score digit
sbc TopScoreDisplay,y ;from lowest to highest, if any top score digit exceeds
dex ;any player digit, borrow will be set until a subsequent
dey ;subtraction clears it (player digit is higher than top)
bpl GetScoreDiff
bcc NoTopSc ;check to see if borrow is still set, if so, no new high score
inx ;increment X and Y once to the start of the score
iny
CopyScore: lda PlayerScoreDisplay,x ;store player's score digits into high score memory area
sta TopScoreDisplay,y
inx
iny
cpy #$06 ;do this until we have stored them all
bcc CopyScore
NoTopSc: rts
;-------------------------------------------------------------------------------------
DefaultSprOffsets:
.db $04, $30, $48, $60, $78, $90, $a8, $c0
.db $d8, $e8, $24, $f8, $fc, $28, $2c
Sprite0Data:
.db $18, $ff, $23, $58
;-------------------------------------------------------------------------------------
InitializeGame:
ldy #$6f ;clear all memory as in initialization procedure,
jsr InitializeMemory ;but this time, clear only as far as $076f
ldy #$1f
ClrSndLoop: sta SoundMemory,y ;clear out memory used
dey ;by the sound engines
bpl ClrSndLoop
lda #$18 ;set demo timer
sta DemoTimer
jsr LoadAreaPointer
InitializeArea:
ldy #$4b ;clear all memory again, only as far as $074b
jsr InitializeMemory ;this is only necessary if branching from
ldx #$21
lda #$00
ClrTimersLoop: sta Timers,x ;clear out memory between
dex ;$0780 and $07a1
bpl ClrTimersLoop
lda HalfwayPage
ldy AltEntranceControl ;if AltEntranceControl not set, use halfway page, if any found
beq StartPage
lda EntrancePage ;otherwise use saved entry page number here
StartPage: sta ScreenLeft_PageLoc ;set as value here
sta CurrentPageLoc ;also set as current page
sta BackloadingFlag ;set flag here if halfway page or saved entry page number found
jsr GetScreenPosition ;get pixel coordinates for screen borders
ldy #$20 ;if on odd numbered page, use $2480 as start of rendering
and #%00000001 ;otherwise use $2080, this address used later as name table
beq SetInitNTHigh ;address for rendering of game area
ldy #$24
SetInitNTHigh: sty CurrentNTAddr_High ;store name table address
ldy #$80
sty CurrentNTAddr_Low
asl ;store LSB of page number in high nybble
asl ;of block buffer column position
asl
asl
sta BlockBufferColumnPos
dec AreaObjectLength ;set area object lengths for all empty
dec AreaObjectLength+1
dec AreaObjectLength+2
lda #$0b ;set value for renderer to update 12 column sets
sta ColumnSets ;12 column sets = 24 metatile columns = 1 1/2 screens
jsr GetAreaDataAddrs ;get enemy and level addresses and load header
lda PrimaryHardMode ;check to see if primary hard mode has been activated
bne SetSecHard ;if so, activate the secondary no matter where we're at
lda WorldNumber ;otherwise check world number
cmp #World5 ;if less than 5, do not activate secondary
bcc CheckHalfway
bne SetSecHard ;if not equal to, then world > 5, thus activate
lda LevelNumber ;otherwise, world 5, so check level number
cmp #Level3 ;if 1 or 2, do not set secondary hard mode flag
bcc CheckHalfway
SetSecHard: inc SecondaryHardMode ;set secondary hard mode flag for areas 5-3 and beyond
CheckHalfway: lda HalfwayPage
beq DoneInitArea
lda #$02 ;if halfway page set, overwrite start position from header
sta PlayerEntranceCtrl
DoneInitArea: lda #Silence ;silence music
sta AreaMusicQueue
lda #$01 ;disable screen output
sta DisableScreenFlag
inc OperMode_Task ;increment one of the modes
rts
;-------------------------------------------------------------------------------------
PrimaryGameSetup:
lda #$01
sta FetchNewGameTimerFlag ;set flag to load game timer from header
sta PlayerSize ;set player's size to small
lda #$02
sta NumberofLives ;give each player three lives
sta OffScr_NumberofLives
SecondaryGameSetup:
lda #$00
sta DisableScreenFlag ;enable screen output
tay
ClearVRLoop: sta VRAM_Buffer1-1,y ;clear buffer at $0300-$03ff
iny
bne ClearVRLoop
sta GameTimerExpiredFlag ;clear game timer exp flag
sta DisableIntermediate ;clear skip lives display flag
sta BackloadingFlag ;clear value here
lda #$ff
sta BalPlatformAlignment ;initialize balance platform assignment flag
lda ScreenLeft_PageLoc ;get left side page location
lsr Mirror_PPU_CTRL_REG1 ;shift LSB of ppu register #1 mirror out
and #$01 ;mask out all but LSB of page location
ror ;rotate LSB of page location into carry then onto mirror
rol Mirror_PPU_CTRL_REG1 ;this is to set the proper PPU name table
jsr GetAreaMusic ;load proper music into queue
lda #$38 ;load sprite shuffle amounts to be used later
sta SprShuffleAmt+2
lda #$48
sta SprShuffleAmt+1
lda #$58
sta SprShuffleAmt
ldx #$0e ;load default OAM offsets into $06e4-$06f2
ShufAmtLoop: lda DefaultSprOffsets,x
sta SprDataOffset,x
dex ;do this until they're all set
bpl ShufAmtLoop
ldy #$03 ;set up sprite #0
ISpr0Loop: lda Sprite0Data,y
sta Sprite_Data,y
dey
bpl ISpr0Loop
jsr DoNothing2 ;these jsrs doesn't do anything useful
jsr DoNothing1
inc Sprite0HitDetectFlag ;set sprite #0 check flag
inc OperMode_Task ;increment to next task
rts
;-------------------------------------------------------------------------------------
;$06 - RAM address low
;$07 - RAM address high
InitializeMemory:
ldx #$07 ;set initial high byte to $0700-$07ff
lda #$00 ;set initial low byte to start of page (at $00 of page)
sta $06
InitPageLoop: stx $07
InitByteLoop: cpx #$01 ;check to see if we're on the stack ($0100-$01ff)
bne InitByte ;if not, go ahead anyway
cpy #$60 ;otherwise, check to see if we're at $0160-$01ff
bcs SkipByte ;if so, skip write
InitByte: sta ($06),y ;otherwise, initialize byte with current low byte in Y
SkipByte: dey
cpy #$ff ;do this until all bytes in page have been erased
bne InitByteLoop
dex ;go onto the next page
bpl InitPageLoop ;do this until all pages of memory have been erased
rts
;-------------------------------------------------------------------------------------
MusicSelectData:
.db WaterMusic, GroundMusic, UndergroundMusic, CastleMusic
.db CloudMusic, PipeIntroMusic
GetAreaMusic:
lda OperMode ;if in title screen mode, leave
beq ExitGetM
lda AltEntranceControl ;check for specific alternate mode of entry
cmp #$02 ;if found, branch without checking starting position
beq ChkAreaType ;from area object data header
ldy #$05 ;select music for pipe intro scene by default
lda PlayerEntranceCtrl ;check value from level header for certain values
cmp #$06
beq StoreMusic ;load music for pipe intro scene if header
cmp #$07 ;start position either value $06 or $07
beq StoreMusic
ChkAreaType: ldy AreaType ;load area type as offset for music bit
lda CloudTypeOverride
beq StoreMusic ;check for cloud type override
ldy #$04 ;select music for cloud type level if found
StoreMusic: lda MusicSelectData,y ;otherwise select appropriate music for level type
sta AreaMusicQueue ;store in queue and leave
ExitGetM: rts
;-------------------------------------------------------------------------------------
PlayerStarting_X_Pos:
.db $28, $18
.db $38, $28
AltYPosOffset:
.db $08, $00
PlayerStarting_Y_Pos:
.db $00, $20, $b0, $50, $00, $00, $b0, $b0
.db $f0
PlayerBGPriorityData:
.db $00, $20, $00, $00, $00, $00, $00, $00
GameTimerData:
.db $20 ;dummy byte, used as part of bg priority data
.db $04, $03, $02
Entrance_GameTimerSetup:
lda ScreenLeft_PageLoc ;set current page for area objects
sta Player_PageLoc ;as page location for player
lda #$28 ;store value here
sta VerticalForceDown ;for fractional movement downwards if necessary
lda #$01 ;set high byte of player position and
sta PlayerFacingDir ;set facing direction so that player faces right
sta Player_Y_HighPos
lda #$00 ;set player state to on the ground by default
sta Player_State
dec Player_CollisionBits ;initialize player's collision bits
ldy #$00 ;initialize halfway page
sty HalfwayPage
lda AreaType ;check area type
bne ChkStPos ;if water type, set swimming flag, otherwise do not set
iny
ChkStPos: sty SwimmingFlag
ldx PlayerEntranceCtrl ;get starting position loaded from header
ldy AltEntranceControl ;check alternate mode of entry flag for 0 or 1
beq SetStPos
cpy #$01
beq SetStPos
ldx AltYPosOffset-2,y ;if not 0 or 1, override $0710 with new offset in X
SetStPos: lda PlayerStarting_X_Pos,y ;load appropriate horizontal position
sta Player_X_Position ;and vertical positions for the player, using
lda PlayerStarting_Y_Pos,x ;AltEntranceControl as offset for horizontal and either $0710
sta Player_Y_Position ;or value that overwrote $0710 as offset for vertical
lda PlayerBGPriorityData,x
sta Player_SprAttrib ;set player sprite attributes using offset in X
jsr GetPlayerColors ;get appropriate player palette
ldy GameTimerSetting ;get timer control value from header
beq ChkOverR ;if set to zero, branch (do not use dummy byte for this)
lda FetchNewGameTimerFlag ;do we need to set the game timer? if not, use
beq ChkOverR ;old game timer setting
lda GameTimerData,y ;if game timer is set and game timer flag is also set,
sta GameTimerDisplay ;use value of game timer control for first digit of game timer
lda #$01
sta GameTimerDisplay+2 ;set last digit of game timer to 1
lsr
sta GameTimerDisplay+1 ;set second digit of game timer
sta FetchNewGameTimerFlag ;clear flag for game timer reset
sta StarInvincibleTimer ;clear star mario timer
ChkOverR: ldy JoypadOverride ;if controller bits not set, branch to skip this part
beq ChkSwimE
lda #$03 ;set player state to climbing
sta Player_State
ldx #$00 ;set offset for first slot, for block object
jsr InitBlock_XY_Pos
lda #$f0 ;set vertical coordinate for block object
sta Block_Y_Position
ldx #$05 ;set offset in X for last enemy object buffer slot
ldy #$00 ;set offset in Y for object coordinates used earlier
jsr Setup_Vine ;do a sub to grow vine
ChkSwimE: ldy AreaType ;if level not water-type,
bne SetPESub ;skip this subroutine
jsr SetupBubble ;otherwise, execute sub to set up air bubbles
SetPESub: lda #$07 ;set to run player entrance subroutine
sta GameEngineSubroutine ;on the next frame of game engine
rts
;-------------------------------------------------------------------------------------
;page numbers are in order from -1 to -4
HalfwayPageNybbles:
.db $56, $40
.db $65, $70
.db $66, $40
.db $66, $40
.db $66, $40
.db $66, $60
.db $65, $70
.db $00, $00
PlayerLoseLife:
inc DisableScreenFlag ;disable screen and sprite 0 check
lda #$00
sta Sprite0HitDetectFlag
lda #Silence ;silence music
sta EventMusicQueue
dec NumberofLives ;take one life from player
bpl StillInGame ;if player still has lives, branch
lda #$00
sta OperMode_Task ;initialize mode task,
lda #GameOverModeValue ;switch to game over mode
sta OperMode ;and leave
rts
StillInGame: lda WorldNumber ;multiply world number by 2 and use
asl ;as offset
tax
lda LevelNumber ;if in area -3 or -4, increment
and #$02 ;offset by one byte, otherwise
beq GetHalfway ;leave offset alone
inx
GetHalfway: ldy HalfwayPageNybbles,x ;get halfway page number with offset
lda LevelNumber ;check area number's LSB
lsr
tya ;if in area -2 or -4, use lower nybble
bcs MaskHPNyb
lsr ;move higher nybble to lower if area
lsr ;number is -1 or -3
lsr
lsr
MaskHPNyb: and #%00001111 ;mask out all but lower nybble
cmp ScreenLeft_PageLoc
beq SetHalfway ;left side of screen must be at the halfway page,
bcc SetHalfway ;otherwise player must start at the
lda #$00 ;beginning of the level
SetHalfway: sta HalfwayPage ;store as halfway page for player
jsr TransposePlayers ;switch players around if 2-player game
jmp ContinueGame ;continue the game
;-------------------------------------------------------------------------------------
GameOverMode:
lda OperMode_Task
jsr JumpEngine
.dw SetupGameOver
.dw ScreenRoutines
.dw RunGameOver
;-------------------------------------------------------------------------------------
SetupGameOver:
lda #$00 ;reset screen routine task control for title screen, game,
sta ScreenRoutineTask ;and game over modes
sta Sprite0HitDetectFlag ;disable sprite 0 check
lda #GameOverMusic
sta EventMusicQueue ;put game over music in secondary queue
inc DisableScreenFlag ;disable screen output
inc OperMode_Task ;set secondary mode to 1
rts
;-------------------------------------------------------------------------------------
RunGameOver:
lda #$00 ;reenable screen
sta DisableScreenFlag
lda SavedJoypad1Bits ;check controller for start pressed
and #Start_Button
bne TerminateGame
lda ScreenTimer ;if not pressed, wait for
bne GameIsOn ;screen timer to expire
TerminateGame:
lda #Silence ;silence music
sta EventMusicQueue
jsr TransposePlayers ;check if other player can keep
bcc ContinueGame ;going, and do so if possible
lda WorldNumber ;otherwise put world number of current
sta ContinueWorld ;player into secret continue function variable
lda #$00
asl ;residual ASL instruction
sta OperMode_Task ;reset all modes to title screen and
sta ScreenTimer ;leave
sta OperMode
rts
ContinueGame:
jsr LoadAreaPointer ;update level pointer with
lda #$01 ;actual world and area numbers, then
sta PlayerSize ;reset player's size, status, and
inc FetchNewGameTimerFlag ;set game timer flag to reload
lda #$00 ;game timer from header
sta TimerControl ;also set flag for timers to count again
sta PlayerStatus
sta GameEngineSubroutine ;reset task for game core
sta OperMode_Task ;set modes and leave
lda #$01 ;if in game over mode, switch back to
sta OperMode ;game mode, because game is still on
GameIsOn: rts
TransposePlayers:
sec ;set carry flag by default to end game
lda NumberOfPlayers ;if only a 1 player game, leave
beq ExTrans
lda OffScr_NumberofLives ;does offscreen player have any lives left?
bmi ExTrans ;branch if not
lda CurrentPlayer ;invert bit to update
eor #%00000001 ;which player is on the screen
sta CurrentPlayer
ldx #$06
TransLoop: lda OnscreenPlayerInfo,x ;transpose the information
pha ;of the onscreen player
lda OffscreenPlayerInfo,x ;with that of the offscreen player
sta OnscreenPlayerInfo,x
pla
sta OffscreenPlayerInfo,x
dex
bpl TransLoop
clc ;clear carry flag to get game going
ExTrans: rts
;-------------------------------------------------------------------------------------
DoNothing1:
lda #$ff ;this is residual code, this value is
sta $06c9 ;not used anywhere in the program
DoNothing2:
rts
;-------------------------------------------------------------------------------------
AreaParserTaskHandler:
ldy AreaParserTaskNum ;check number of tasks here
bne DoAPTasks ;if already set, go ahead
ldy #$08
sty AreaParserTaskNum ;otherwise, set eight by default
DoAPTasks: dey
tya
jsr AreaParserTasks
dec AreaParserTaskNum ;if all tasks not complete do not
bne SkipATRender ;render attribute table yet
jsr RenderAttributeTables
SkipATRender: rts
AreaParserTasks:
jsr JumpEngine
.dw IncrementColumnPos
.dw RenderAreaGraphics
.dw RenderAreaGraphics
.dw AreaParserCore
.dw IncrementColumnPos
.dw RenderAreaGraphics
.dw RenderAreaGraphics
.dw AreaParserCore
;-------------------------------------------------------------------------------------
IncrementColumnPos:
inc CurrentColumnPos ;increment column where we're at
lda CurrentColumnPos
and #%00001111 ;mask out higher nybble
bne NoColWrap
sta CurrentColumnPos ;if no bits left set, wrap back to zero (0-f)
inc CurrentPageLoc ;and increment page number where we're at
NoColWrap: inc BlockBufferColumnPos ;increment column offset where we're at
lda BlockBufferColumnPos
and #%00011111 ;mask out all but 5 LSB (0-1f)
sta BlockBufferColumnPos ;and save
rts
;-------------------------------------------------------------------------------------
;$00 - used as counter, store for low nybble for background, ceiling byte for terrain
;$01 - used to store floor byte for terrain
;$07 - used to store terrain metatile
;$06-$07 - used to store block buffer address
BSceneDataOffsets:
.db $00, $30, $60
BackSceneryData:
.db $93, $00, $00, $11, $12, $12, $13, $00 ;clouds
.db $00, $51, $52, $53, $00, $00, $00, $00
.db $00, $00, $01, $02, $02, $03, $00, $00
.db $00, $00, $00, $00, $91, $92, $93, $00
.db $00, $00, $00, $51, $52, $53, $41, $42
.db $43, $00, $00, $00, $00, $00, $91, $92
.db $97, $87, $88, $89, $99, $00, $00, $00 ;mountains and bushes
.db $11, $12, $13, $a4, $a5, $a5, $a5, $a6
.db $97, $98, $99, $01, $02, $03, $00, $a4
.db $a5, $a6, $00, $11, $12, $12, $12, $13
.db $00, $00, $00, $00, $01, $02, $02, $03
.db $00, $a4, $a5, $a5, $a6, $00, $00, $00
.db $11, $12, $12, $13, $00, $00, $00, $00 ;trees and fences
.db $00, $00, $00, $9c, $00, $8b, $aa, $aa
.db $aa, $aa, $11, $12, $13, $8b, $00, $9c
.db $9c, $00, $00, $01, $02, $03, $11, $12
.db $12, $13, $00, $00, $00, $00, $aa, $aa
.db $9c, $aa, $00, $8b, $00, $01, $02, $03
BackSceneryMetatiles:
.db $80, $83, $00 ;cloud left
.db $81, $84, $00 ;cloud middle
.db $82, $85, $00 ;cloud right
.db $02, $00, $00 ;bush left
.db $03, $00, $00 ;bush middle
.db $04, $00, $00 ;bush right
.db $00, $05, $06 ;mountain left
.db $07, $06, $0a ;mountain middle
.db $00, $08, $09 ;mountain right
.db $4d, $00, $00 ;fence
.db $0d, $0f, $4e ;tall tree
.db $0e, $4e, $4e ;short tree
FSceneDataOffsets:
.db $00, $0d, $1a
ForeSceneryData:
.db $86, $87, $87, $87, $87, $87, $87 ;in water
.db $87, $87, $87, $87, $69, $69
.db $00, $00, $00, $00, $00, $45, $47 ;wall
.db $47, $47, $47, $47, $00, $00
.db $00, $00, $00, $00, $00, $00, $00 ;over water
.db $00, $00, $00, $00, $86, $87
TerrainMetatiles:
.db $69, $54, $52, $62
TerrainRenderBits:
.db %00000000, %00000000 ;no ceiling or floor
.db %00000000, %00011000 ;no ceiling, floor 2
.db %00000001, %00011000 ;ceiling 1, floor 2
.db %00000111, %00011000 ;ceiling 3, floor 2
.db %00001111, %00011000 ;ceiling 4, floor 2
.db %11111111, %00011000 ;ceiling 8, floor 2
.db %00000001, %00011111 ;ceiling 1, floor 5
.db %00000111, %00011111 ;ceiling 3, floor 5
.db %00001111, %00011111 ;ceiling 4, floor 5
.db %10000001, %00011111 ;ceiling 1, floor 6
.db %00000001, %00000000 ;ceiling 1, no floor
.db %10001111, %00011111 ;ceiling 4, floor 6
.db %11110001, %00011111 ;ceiling 1, floor 9
.db %11111001, %00011000 ;ceiling 1, middle 5, floor 2
.db %11110001, %00011000 ;ceiling 1, middle 4, floor 2
.db %11111111, %00011111 ;completely solid top to bottom
AreaParserCore:
lda BackloadingFlag ;check to see if we are starting right of start
beq RenderSceneryTerrain ;if not, go ahead and render background, foreground and terrain
jsr ProcessAreaData ;otherwise skip ahead and load level data
RenderSceneryTerrain:
ldx #$0c
lda #$00
ClrMTBuf: sta MetatileBuffer,x ;clear out metatile buffer
dex
bpl ClrMTBuf
ldy BackgroundScenery ;do we need to render the background scenery?
beq RendFore ;if not, skip to check the foreground
lda CurrentPageLoc ;otherwise check for every third page
ThirdP: cmp #$03
bmi RendBack ;if less than three we're there
sec
sbc #$03 ;if 3 or more, subtract 3 and
bpl ThirdP ;do an unconditional branch
RendBack: asl ;move results to higher nybble
asl
asl
asl
adc BSceneDataOffsets-1,y ;add to it offset loaded from here
adc CurrentColumnPos ;add to the result our current column position
tax
lda BackSceneryData,x ;load data from sum of offsets
beq RendFore ;if zero, no scenery for that part
pha
and #$0f ;save to stack and clear high nybble
sec
sbc #$01 ;subtract one (because low nybble is $01-$0c)
sta $00 ;save low nybble
asl ;multiply by three (shift to left and add result to old one)
adc $00 ;note that since d7 was nulled, the carry flag is always clear
tax ;save as offset for background scenery metatile data
pla ;get high nybble from stack, move low
lsr
lsr
lsr
lsr
tay ;use as second offset (used to determine height)
lda #$03 ;use previously saved memory location for counter
sta $00
SceLoop1: lda BackSceneryMetatiles,x ;load metatile data from offset of (lsb - 1) * 3
sta MetatileBuffer,y ;store into buffer from offset of (msb / 16)
inx
iny
cpy #$0b ;if at this location, leave loop
beq RendFore
dec $00 ;decrement until counter expires, barring exception
bne SceLoop1
RendFore: ldx ForegroundScenery ;check for foreground data needed or not
beq RendTerr ;if not, skip this part
ldy FSceneDataOffsets-1,x ;load offset from location offset by header value, then
ldx #$00 ;reinit X
SceLoop2: lda ForeSceneryData,y ;load data until counter expires
beq NoFore ;do not store if zero found
sta MetatileBuffer,x
NoFore: iny
inx
cpx #$0d ;store up to end of metatile buffer
bne SceLoop2
RendTerr: ldy AreaType ;check world type for water level
bne TerMTile ;if not water level, skip this part
lda WorldNumber ;check world number, if not world number eight
cmp #World8 ;then skip this part
bne TerMTile
lda #$62 ;if set as water level and world number eight,
jmp StoreMT ;use castle wall metatile as terrain type
TerMTile: lda TerrainMetatiles,y ;otherwise get appropriate metatile for area type
ldy CloudTypeOverride ;check for cloud type override
beq StoreMT ;if not set, keep value otherwise
lda #$88 ;use cloud block terrain
StoreMT: sta $07 ;store value here
ldx #$00 ;initialize X, use as metatile buffer offset
lda TerrainControl ;use yet another value from the header
asl ;multiply by 2 and use as yet another offset
tay
TerrLoop: lda TerrainRenderBits,y ;get one of the terrain rendering bit data
sta $00
iny ;increment Y and use as offset next time around
sty $01
lda CloudTypeOverride ;skip if value here is zero
beq NoCloud2
cpx #$00 ;otherwise, check if we're doing the ceiling byte
beq NoCloud2
lda $00 ;if not, mask out all but d3
and #%00001000
sta $00
NoCloud2: ldy #$00 ;start at beginning of bitmasks
TerrBChk: lda Bitmasks,y ;load bitmask, then perform AND on contents of first byte
bit $00
beq NextTBit ;if not set, skip this part (do not write terrain to buffer)
lda $07
sta MetatileBuffer,x ;load terrain type metatile number and store into buffer here
NextTBit: inx ;continue until end of buffer
cpx #$0d
beq RendBBuf ;if we're at the end, break out of this loop
lda AreaType ;check world type for underground area
cmp #$02
bne EndUChk ;if not underground, skip this part
cpx #$0b
bne EndUChk ;if we're at the bottom of the screen, override
lda #$54 ;old terrain type with ground level terrain type
sta $07
EndUChk: iny ;increment bitmasks offset in Y
cpy #$08
bne TerrBChk ;if not all bits checked, loop back
ldy $01
bne TerrLoop ;unconditional branch, use Y to load next byte
RendBBuf: jsr ProcessAreaData ;do the area data loading routine now
lda BlockBufferColumnPos
jsr GetBlockBufferAddr ;get block buffer address from where we're at
ldx #$00
ldy #$00 ;init index regs and start at beginning of smaller buffer
ChkMTLow: sty $00
lda MetatileBuffer,x ;load stored metatile number
and #%11000000 ;mask out all but 2 MSB
asl
rol ;make %xx000000 into %000000xx
rol
tay ;use as offset in Y
lda MetatileBuffer,x ;reload original unmasked value here
cmp BlockBuffLowBounds,y ;check for certain values depending on bits set
bcs StrBlock ;if equal or greater, branch
lda #$00 ;if less, init value before storing
StrBlock: ldy $00 ;get offset for block buffer
sta ($06),y ;store value into block buffer
tya
clc ;add 16 (move down one row) to offset
adc #$10
tay
inx ;increment column value
cpx #$0d
bcc ChkMTLow ;continue until we pass last row, then leave
rts
;numbers lower than these with the same attribute bits
;will not be stored in the block buffer
BlockBuffLowBounds:
.db $10, $51, $88, $c0
;-------------------------------------------------------------------------------------
;$00 - used to store area object identifier
;$07 - used as adder to find proper area object code
ProcessAreaData:
ldx #$02 ;start at the end of area object buffer
ProcADLoop: stx ObjectOffset
lda #$00 ;reset flag
sta BehindAreaParserFlag
ldy AreaDataOffset ;get offset of area data pointer
lda (AreaData),y ;get first byte of area object
cmp #$fd ;if end-of-area, skip all this crap
beq RdyDecode
lda AreaObjectLength,x ;check area object buffer flag
bpl RdyDecode ;if buffer not negative, branch, otherwise
iny
lda (AreaData),y ;get second byte of area object
asl ;check for page select bit (d7), branch if not set
bcc Chk1Row13
lda AreaObjectPageSel ;check page select
bne Chk1Row13
inc AreaObjectPageSel ;if not already set, set it now
inc AreaObjectPageLoc ;and increment page location
Chk1Row13: dey
lda (AreaData),y ;reread first byte of level object
and #$0f ;mask out high nybble
cmp #$0d ;row 13?
bne Chk1Row14
iny ;if so, reread second byte of level object
lda (AreaData),y
dey ;decrement to get ready to read first byte
and #%01000000 ;check for d6 set (if not, object is page control)
bne CheckRear
lda AreaObjectPageSel ;if page select is set, do not reread
bne CheckRear
iny ;if d6 not set, reread second byte
lda (AreaData),y
and #%00011111 ;mask out all but 5 LSB and store in page control
sta AreaObjectPageLoc
inc AreaObjectPageSel ;increment page select
jmp NextAObj
Chk1Row14: cmp #$0e ;row 14?
bne CheckRear
lda BackloadingFlag ;check flag for saved page number and branch if set
bne RdyDecode ;to render the object (otherwise bg might not look right)
CheckRear: lda AreaObjectPageLoc ;check to see if current page of level object is
cmp CurrentPageLoc ;behind current page of renderer
bcc SetBehind ;if so branch
RdyDecode: jsr DecodeAreaData ;do sub and do not turn on flag
jmp ChkLength
SetBehind: inc BehindAreaParserFlag ;turn on flag if object is behind renderer
NextAObj: jsr IncAreaObjOffset ;increment buffer offset and move on
ChkLength: ldx ObjectOffset ;get buffer offset
lda AreaObjectLength,x ;check object length for anything stored here
bmi ProcLoopb ;if not, branch to handle loopback
dec AreaObjectLength,x ;otherwise decrement length or get rid of it
ProcLoopb: dex ;decrement buffer offset
bpl ProcADLoop ;and loopback unless exceeded buffer
lda BehindAreaParserFlag ;check for flag set if objects were behind renderer
bne ProcessAreaData ;branch if true to load more level data, otherwise
lda BackloadingFlag ;check for flag set if starting right of page $00
bne ProcessAreaData ;branch if true to load more level data, otherwise leave
EndAParse: rts
IncAreaObjOffset:
inc AreaDataOffset ;increment offset of level pointer
inc AreaDataOffset
lda #$00 ;reset page select
sta AreaObjectPageSel
rts
DecodeAreaData:
lda AreaObjectLength,x ;check current buffer flag
bmi Chk1stB
ldy AreaObjOffsetBuffer,x ;if not, get offset from buffer
Chk1stB: ldx #$10 ;load offset of 16 for special row 15
lda (AreaData),y ;get first byte of level object again
cmp #$fd
beq EndAParse ;if end of level, leave this routine
and #$0f ;otherwise, mask out low nybble
cmp #$0f ;row 15?
beq ChkRow14 ;if so, keep the offset of 16
ldx #$08 ;otherwise load offset of 8 for special row 12
cmp #$0c ;row 12?
beq ChkRow14 ;if so, keep the offset value of 8
ldx #$00 ;otherwise nullify value by default
ChkRow14: stx $07 ;store whatever value we just loaded here
ldx ObjectOffset ;get object offset again
cmp #$0e ;row 14?
bne ChkRow13
lda #$00 ;if so, load offset with $00
sta $07
lda #$2e ;and load A with another value
bne NormObj ;unconditional branch
ChkRow13: cmp #$0d ;row 13?
bne ChkSRows
lda #$22 ;if so, load offset with 34
sta $07
iny ;get next byte
lda (AreaData),y
and #%01000000 ;mask out all but d6 (page control obj bit)
beq LeavePar ;if d6 clear, branch to leave (we handled this earlier)
lda (AreaData),y ;otherwise, get byte again
and #%01111111 ;mask out d7
cmp #$4b ;check for loop command in low nybble
bne Mask2MSB ;(plus d6 set for object other than page control)
inc LoopCommand ;if loop command, set loop command flag
Mask2MSB: and #%00111111 ;mask out d7 and d6
jmp NormObj ;and jump
ChkSRows: cmp #$0c ;row 12-15?
bcs SpecObj
iny ;if not, get second byte of level object
lda (AreaData),y
and #%01110000 ;mask out all but d6-d4
bne LrgObj ;if any bits set, branch to handle large object
lda #$16
sta $07 ;otherwise set offset of 24 for small object
lda (AreaData),y ;reload second byte of level object
and #%00001111 ;mask out higher nybble and jump
jmp NormObj
LrgObj: sta $00 ;store value here (branch for large objects)
cmp #$70 ;check for vertical pipe object
bne NotWPipe
lda (AreaData),y ;if not, reload second byte
and #%00001000 ;mask out all but d3 (usage control bit)
beq NotWPipe ;if d3 clear, branch to get original value
lda #$00 ;otherwise, nullify value for warp pipe
sta $00
NotWPipe: lda $00 ;get value and jump ahead
jmp MoveAOId
SpecObj: iny ;branch here for rows 12-15
lda (AreaData),y
and #%01110000 ;get next byte and mask out all but d6-d4
MoveAOId: lsr ;move d6-d4 to lower nybble
lsr
lsr
lsr
NormObj: sta $00 ;store value here (branch for small objects and rows 13 and 14)
lda AreaObjectLength,x ;is there something stored here already?
bpl RunAObj ;if so, branch to do its particular sub
lda AreaObjectPageLoc ;otherwise check to see if the object we've loaded is on the
cmp CurrentPageLoc ;same page as the renderer, and if so, branch
beq InitRear
ldy AreaDataOffset ;if not, get old offset of level pointer
lda (AreaData),y ;and reload first byte
and #%00001111
cmp #$0e ;row 14?
bne LeavePar
lda BackloadingFlag ;if so, check backloading flag
bne StrAObj ;if set, branch to render object, else leave
LeavePar: rts
InitRear: lda BackloadingFlag ;check backloading flag to see if it's been initialized
beq BackColC ;branch to column-wise check
lda #$00 ;if not, initialize both backloading and
sta BackloadingFlag ;behind-renderer flags and leave
sta BehindAreaParserFlag
sta ObjectOffset
LoopCmdE: rts
BackColC: ldy AreaDataOffset ;get first byte again
lda (AreaData),y
and #%11110000 ;mask out low nybble and move high to low
lsr
lsr
lsr
lsr
cmp CurrentColumnPos ;is this where we're at?
bne LeavePar ;if not, branch to leave
StrAObj: lda AreaDataOffset ;if so, load area obj offset and store in buffer
sta AreaObjOffsetBuffer,x
jsr IncAreaObjOffset ;do sub to increment to next object data
RunAObj: lda $00 ;get stored value and add offset to it
clc ;then use the jump engine with current contents of A
adc $07
jsr JumpEngine
;large objects (rows $00-$0b or 00-11, d6-d4 set)
.dw VerticalPipe ;used by warp pipes
.dw AreaStyleObject
.dw RowOfBricks
.dw RowOfSolidBlocks
.dw RowOfCoins
.dw ColumnOfBricks
.dw ColumnOfSolidBlocks
.dw VerticalPipe ;used by decoration pipes
;objects for special row $0c or 12
.dw Hole_Empty
.dw PulleyRopeObject
.dw Bridge_High
.dw Bridge_Middle
.dw Bridge_Low
.dw Hole_Water
.dw QuestionBlockRow_High
.dw QuestionBlockRow_Low
;objects for special row $0f or 15
.dw EndlessRope
.dw BalancePlatRope
.dw CastleObject
.dw StaircaseObject
.dw ExitPipe
.dw FlagBalls_Residual
;small objects (rows $00-$0b or 00-11, d6-d4 all clear)
.dw QuestionBlock ;power-up
.dw QuestionBlock ;coin
.dw QuestionBlock ;hidden, coin
.dw Hidden1UpBlock ;hidden, 1-up
.dw BrickWithItem ;brick, power-up
.dw BrickWithItem ;brick, vine
.dw BrickWithItem ;brick, star
.dw BrickWithCoins ;brick, coins
.dw BrickWithItem ;brick, 1-up
.dw WaterPipe
.dw EmptyBlock
.dw Jumpspring
;objects for special row $0d or 13 (d6 set)
.dw IntroPipe
.dw FlagpoleObject
.dw AxeObj
.dw ChainObj
.dw CastleBridgeObj
.dw ScrollLockObject_Warp
.dw ScrollLockObject
.dw ScrollLockObject
.dw AreaFrenzy ;flying cheep-cheeps
.dw AreaFrenzy ;bullet bills or swimming cheep-cheeps
.dw AreaFrenzy ;stop frenzy
.dw LoopCmdE
;object for special row $0e or 14
.dw AlterAreaAttributes
;-------------------------------------------------------------------------------------
;(these apply to all area object subroutines in this section unless otherwise stated)
;$00 - used to store offset used to find object code
;$07 - starts with adder from area parser, used to store row offset
AlterAreaAttributes:
ldy AreaObjOffsetBuffer,x ;load offset for level object data saved in buffer
iny ;load second byte
lda (AreaData),y
pha ;save in stack for now
and #%01000000
bne Alter2 ;branch if d6 is set
pla
pha ;pull and push offset to copy to A
and #%00001111 ;mask out high nybble and store as
sta TerrainControl ;new terrain height type bits
pla
and #%00110000 ;pull and mask out all but d5 and d4
lsr ;move bits to lower nybble and store
lsr ;as new background scenery bits
lsr
lsr
sta BackgroundScenery ;then leave
rts
Alter2: pla
and #%00000111 ;mask out all but 3 LSB
cmp #$04 ;if four or greater, set color control bits
bcc SetFore ;and nullify foreground scenery bits
sta BackgroundColorCtrl
lda #$00
SetFore: sta ForegroundScenery ;otherwise set new foreground scenery bits
rts
;--------------------------------
ScrollLockObject_Warp:
ldx #$04 ;load value of 4 for game text routine as default
lda WorldNumber ;warp zone (4-3-2), then check world number
beq WarpNum
inx ;if world number > 1, increment for next warp zone (5)
ldy AreaType ;check area type
dey
bne WarpNum ;if ground area type, increment for last warp zone
inx ;(8-7-6) and move on
WarpNum: txa
sta WarpZoneControl ;store number here to be used by warp zone routine
jsr WriteGameText ;print text and warp zone numbers
lda #PiranhaPlant
jsr KillEnemies ;load identifier for piranha plants and do sub
ScrollLockObject:
lda ScrollLock ;invert scroll lock to turn it on
eor #%00000001
sta ScrollLock
rts
;--------------------------------
;$00 - used to store enemy identifier in KillEnemies
KillEnemies:
sta $00 ;store identifier here
lda #$00
ldx #$04 ;check for identifier in enemy object buffer
KillELoop: ldy Enemy_ID,x
cpy $00 ;if not found, branch
bne NoKillE
sta Enemy_Flag,x ;if found, deactivate enemy object flag
NoKillE: dex ;do this until all slots are checked
bpl KillELoop
rts
;--------------------------------
FrenzyIDData:
.db FlyCheepCheepFrenzy, BBill_CCheep_Frenzy, Stop_Frenzy
AreaFrenzy: ldx $00 ;use area object identifier bit as offset
lda FrenzyIDData-8,x ;note that it starts at 8, thus weird address here
ldy #$05
FreCompLoop: dey ;check regular slots of enemy object buffer
bmi ExitAFrenzy ;if all slots checked and enemy object not found, branch to store
cmp Enemy_ID,y ;check for enemy object in buffer versus frenzy object
bne FreCompLoop
lda #$00 ;if enemy object already present, nullify queue and leave
ExitAFrenzy: sta EnemyFrenzyQueue ;store enemy into frenzy queue
rts
;--------------------------------
;$06 - used by MushroomLedge to store length
AreaStyleObject:
lda AreaStyle ;load level object style and jump to the right sub
jsr JumpEngine
.dw TreeLedge ;also used for cloud type levels
.dw MushroomLedge
.dw BulletBillCannon
TreeLedge:
jsr GetLrgObjAttrib ;get row and length of green ledge
lda AreaObjectLength,x ;check length counter for expiration
beq EndTreeL
bpl MidTreeL
tya
sta AreaObjectLength,x ;store lower nybble into buffer flag as length of ledge
lda CurrentPageLoc
ora CurrentColumnPos ;are we at the start of the level?
beq MidTreeL
lda #$16 ;render start of tree ledge
jmp NoUnder
MidTreeL: ldx $07
lda #$17 ;render middle of tree ledge
sta MetatileBuffer,x ;note that this is also used if ledge position is
lda #$4c ;at the start of level for continuous effect
jmp AllUnder ;now render the part underneath
EndTreeL: lda #$18 ;render end of tree ledge
jmp NoUnder
MushroomLedge:
jsr ChkLrgObjLength ;get shroom dimensions
sty $06 ;store length here for now
bcc EndMushL
lda AreaObjectLength,x ;divide length by 2 and store elsewhere
lsr
sta MushroomLedgeHalfLen,x
lda #$19 ;render start of mushroom
jmp NoUnder
EndMushL: lda #$1b ;if at the end, render end of mushroom
ldy AreaObjectLength,x
beq NoUnder
lda MushroomLedgeHalfLen,x ;get divided length and store where length
sta $06 ;was stored originally
ldx $07
lda #$1a
sta MetatileBuffer,x ;render middle of mushroom
cpy $06 ;are we smack dab in the center?
bne MushLExit ;if not, branch to leave
inx
lda #$4f
sta MetatileBuffer,x ;render stem top of mushroom underneath the middle
lda #$50
AllUnder: inx
ldy #$0f ;set $0f to render all way down
jmp RenderUnderPart ;now render the stem of mushroom
NoUnder: ldx $07 ;load row of ledge
ldy #$00 ;set 0 for no bottom on this part
jmp RenderUnderPart
;--------------------------------
;tiles used by pulleys and rope object
PulleyRopeMetatiles:
.db $42, $41, $43
PulleyRopeObject:
jsr ChkLrgObjLength ;get length of pulley/rope object
ldy #$00 ;initialize metatile offset
bcs RenderPul ;if starting, render left pulley
iny
lda AreaObjectLength,x ;if not at the end, render rope
bne RenderPul
iny ;otherwise render right pulley
RenderPul: lda PulleyRopeMetatiles,y
sta MetatileBuffer ;render at the top of the screen
MushLExit: rts ;and leave
;--------------------------------
;$06 - used to store upper limit of rows for CastleObject
CastleMetatiles:
.db $00, $45, $45, $45, $00
.db $00, $48, $47, $46, $00
.db $45, $49, $49, $49, $45
.db $47, $47, $4a, $47, $47
.db $47, $47, $4b, $47, $47
.db $49, $49, $49, $49, $49
.db $47, $4a, $47, $4a, $47
.db $47, $4b, $47, $4b, $47
.db $47, $47, $47, $47, $47
.db $4a, $47, $4a, $47, $4a
.db $4b, $47, $4b, $47, $4b
CastleObject:
jsr GetLrgObjAttrib ;save lower nybble as starting row
sty $07 ;if starting row is above $0a, game will crash!!!
ldy #$04
jsr ChkLrgObjFixedLength ;load length of castle if not already loaded
txa
pha ;save obj buffer offset to stack
ldy AreaObjectLength,x ;use current length as offset for castle data
ldx $07 ;begin at starting row
lda #$0b
sta $06 ;load upper limit of number of rows to print
CRendLoop: lda CastleMetatiles,y ;load current byte using offset
sta MetatileBuffer,x
inx ;store in buffer and increment buffer offset
lda $06
beq ChkCFloor ;have we reached upper limit yet?
iny ;if not, increment column-wise
iny ;to byte in next row
iny
iny
iny
dec $06 ;move closer to upper limit
ChkCFloor: cpx #$0b ;have we reached the row just before floor?
bne CRendLoop ;if not, go back and do another row
pla
tax ;get obj buffer offset from before
lda CurrentPageLoc
beq ExitCastle ;if we're at page 0, we do not need to do anything else
lda AreaObjectLength,x ;check length
cmp #$01 ;if length almost about to expire, put brick at floor
beq PlayerStop
ldy $07 ;check starting row for tall castle ($00)
bne NotTall
cmp #$03 ;if found, then check to see if we're at the second column
beq PlayerStop
NotTall: cmp #$02 ;if not tall castle, check to see if we're at the third column
bne ExitCastle ;if we aren't and the castle is tall, don't create flag yet
jsr GetAreaObjXPosition ;otherwise, obtain and save horizontal pixel coordinate
pha
jsr FindEmptyEnemySlot ;find an empty place on the enemy object buffer
pla
sta Enemy_X_Position,x ;then write horizontal coordinate for star flag
lda CurrentPageLoc
sta Enemy_PageLoc,x ;set page location for star flag
lda #$01
sta Enemy_Y_HighPos,x ;set vertical high byte
sta Enemy_Flag,x ;set flag for buffer
lda #$90
sta Enemy_Y_Position,x ;set vertical coordinate
lda #StarFlagObject ;set star flag value in buffer itself
sta Enemy_ID,x
rts
PlayerStop: ldy #$52 ;put brick at floor to stop player at end of level
sty MetatileBuffer+10 ;this is only done if we're on the second column
ExitCastle: rts
;--------------------------------
WaterPipe:
jsr GetLrgObjAttrib ;get row and lower nybble
ldy AreaObjectLength,x ;get length (residual code, water pipe is 1 col thick)
ldx $07 ;get row
lda #$6b
sta MetatileBuffer,x ;draw something here and below it
lda #$6c
sta MetatileBuffer+1,x
rts
;--------------------------------
;$05 - used to store length of vertical shaft in RenderSidewaysPipe
;$06 - used to store leftover horizontal length in RenderSidewaysPipe
; and vertical length in VerticalPipe and GetPipeHeight
IntroPipe:
ldy #$03 ;check if length set, if not set, set it
jsr ChkLrgObjFixedLength
ldy #$0a ;set fixed value and render the sideways part
jsr RenderSidewaysPipe
bcs NoBlankP ;if carry flag set, not time to draw vertical pipe part
ldx #$06 ;blank everything above the vertical pipe part
VPipeSectLoop: lda #$00 ;all the way to the top of the screen
sta MetatileBuffer,x ;because otherwise it will look like exit pipe
dex
bpl VPipeSectLoop
lda VerticalPipeData,y ;draw the end of the vertical pipe part
sta MetatileBuffer+7
NoBlankP: rts
SidePipeShaftData:
.db $15, $14 ;used to control whether or not vertical pipe shaft
.db $00, $00 ;is drawn, and if so, controls the metatile number
SidePipeTopPart:
.db $15, $1e ;top part of sideways part of pipe
.db $1d, $1c
SidePipeBottomPart:
.db $15, $21 ;bottom part of sideways part of pipe
.db $20, $1f
ExitPipe:
ldy #$03 ;check if length set, if not set, set it
jsr ChkLrgObjFixedLength
jsr GetLrgObjAttrib ;get vertical length, then plow on through RenderSidewaysPipe
RenderSidewaysPipe:
dey ;decrement twice to make room for shaft at bottom
dey ;and store here for now as vertical length
sty $05
ldy AreaObjectLength,x ;get length left over and store here
sty $06
ldx $05 ;get vertical length plus one, use as buffer offset
inx
lda SidePipeShaftData,y ;check for value $00 based on horizontal offset
cmp #$00
beq DrawSidePart ;if found, do not draw the vertical pipe shaft
ldx #$00
ldy $05 ;init buffer offset and get vertical length
jsr RenderUnderPart ;and render vertical shaft using tile number in A
clc ;clear carry flag to be used by IntroPipe
DrawSidePart: ldy $06 ;render side pipe part at the bottom
lda SidePipeTopPart,y
sta MetatileBuffer,x ;note that the pipe parts are stored
lda SidePipeBottomPart,y ;backwards horizontally
sta MetatileBuffer+1,x
rts
VerticalPipeData:
.db $11, $10 ;used by pipes that lead somewhere
.db $15, $14
.db $13, $12 ;used by decoration pipes
.db $15, $14
VerticalPipe:
jsr GetPipeHeight
lda $00 ;check to see if value was nullified earlier
beq WarpPipe ;(if d3, the usage control bit of second byte, was set)
iny
iny
iny
iny ;add four if usage control bit was not set
WarpPipe: tya ;save value in stack
pha
lda AreaNumber
ora WorldNumber ;if at world 1-1, do not add piranha plant ever
beq DrawPipe
ldy AreaObjectLength,x ;if on second column of pipe, branch
beq DrawPipe ;(because we only need to do this once)
jsr FindEmptyEnemySlot ;check for an empty moving data buffer space
bcs DrawPipe ;if not found, too many enemies, thus skip
jsr GetAreaObjXPosition ;get horizontal pixel coordinate
clc
adc #$08 ;add eight to put the piranha plant in the center
sta Enemy_X_Position,x ;store as enemy's horizontal coordinate
lda CurrentPageLoc ;add carry to current page number
adc #$00
sta Enemy_PageLoc,x ;store as enemy's page coordinate
lda #$01
sta Enemy_Y_HighPos,x
sta Enemy_Flag,x ;activate enemy flag
jsr GetAreaObjYPosition ;get piranha plant's vertical coordinate and store here
sta Enemy_Y_Position,x
lda #PiranhaPlant ;write piranha plant's value into buffer
sta Enemy_ID,x
jsr InitPiranhaPlant
DrawPipe: pla ;get value saved earlier and use as Y
tay
ldx $07 ;get buffer offset
lda VerticalPipeData,y ;draw the appropriate pipe with the Y we loaded earlier
sta MetatileBuffer,x ;render the top of the pipe
inx
lda VerticalPipeData+2,y ;render the rest of the pipe
ldy $06 ;subtract one from length and render the part underneath
dey
jmp RenderUnderPart
GetPipeHeight:
ldy #$01 ;check for length loaded, if not, load
jsr ChkLrgObjFixedLength ;pipe length of 2 (horizontal)
jsr GetLrgObjAttrib
tya ;get saved lower nybble as height
and #$07 ;save only the three lower bits as
sta $06 ;vertical length, then load Y with
ldy AreaObjectLength,x ;length left over
rts
FindEmptyEnemySlot:
ldx #$00 ;start at first enemy slot
EmptyChkLoop: clc ;clear carry flag by default
lda Enemy_Flag,x ;check enemy buffer for nonzero
beq ExitEmptyChk ;if zero, leave
inx
cpx #$05 ;if nonzero, check next value
bne EmptyChkLoop
ExitEmptyChk: rts ;if all values nonzero, carry flag is set
;--------------------------------
Hole_Water:
jsr ChkLrgObjLength ;get low nybble and save as length
lda #$86 ;render waves
sta MetatileBuffer+10
ldx #$0b
ldy #$01 ;now render the water underneath
lda #$87
jmp RenderUnderPart
;--------------------------------
QuestionBlockRow_High:
lda #$03 ;start on the fourth row
.db $2c ;BIT instruction opcode
QuestionBlockRow_Low:
lda #$07 ;start on the eighth row
pha ;save whatever row to the stack for now
jsr ChkLrgObjLength ;get low nybble and save as length
pla
tax ;render question boxes with coins
lda #$c0
sta MetatileBuffer,x
rts
;--------------------------------
Bridge_High:
lda #$06 ;start on the seventh row from top of screen
.db $2c ;BIT instruction opcode
Bridge_Middle:
lda #$07 ;start on the eighth row
.db $2c ;BIT instruction opcode
Bridge_Low:
lda #$09 ;start on the tenth row
pha ;save whatever row to the stack for now
jsr ChkLrgObjLength ;get low nybble and save as length
pla
tax ;render bridge railing
lda #$0b
sta MetatileBuffer,x
inx
ldy #$00 ;now render the bridge itself
lda #$63
jmp RenderUnderPart
;--------------------------------
FlagBalls_Residual:
jsr GetLrgObjAttrib ;get low nybble from object byte
ldx #$02 ;render flag balls on third row from top
lda #$6d ;of screen downwards based on low nybble
jmp RenderUnderPart
;--------------------------------
FlagpoleObject:
lda #$24 ;render flagpole ball on top
sta MetatileBuffer
ldx #$01 ;now render the flagpole shaft
ldy #$08
lda #$25
jsr RenderUnderPart
lda #$61 ;render solid block at the bottom
sta MetatileBuffer+10
jsr GetAreaObjXPosition
sec ;get pixel coordinate of where the flagpole is,
sbc #$08 ;subtract eight pixels and use as horizontal
sta Enemy_X_Position+5 ;coordinate for the flag
lda CurrentPageLoc
sbc #$00 ;subtract borrow from page location and use as
sta Enemy_PageLoc+5 ;page location for the flag
lda #$30
sta Enemy_Y_Position+5 ;set vertical coordinate for flag
lda #$b0
sta FlagpoleFNum_Y_Pos ;set initial vertical coordinate for flagpole's floatey number
lda #FlagpoleFlagObject
sta Enemy_ID+5 ;set flag identifier, note that identifier and coordinates
inc Enemy_Flag+5 ;use last space in enemy object buffer
rts
;--------------------------------
EndlessRope:
ldx #$00 ;render rope from the top to the bottom of screen
ldy #$0f
jmp DrawRope
BalancePlatRope:
txa ;save object buffer offset for now
pha
ldx #$01 ;blank out all from second row to the bottom
ldy #$0f ;with blank used for balance platform rope
lda #$44
jsr RenderUnderPart
pla ;get back object buffer offset
tax
jsr GetLrgObjAttrib ;get vertical length from lower nybble
ldx #$01
DrawRope: lda #$40 ;render the actual rope
jmp RenderUnderPart
;--------------------------------
CoinMetatileData:
.db $c3, $c2, $c2, $c2
RowOfCoins:
ldy AreaType ;get area type
lda CoinMetatileData,y ;load appropriate coin metatile
jmp GetRow
;--------------------------------
C_ObjectRow:
.db $06, $07, $08
C_ObjectMetatile:
.db $c5, $0c, $89
CastleBridgeObj:
ldy #$0c ;load length of 13 columns
jsr ChkLrgObjFixedLength
jmp ChainObj
AxeObj:
lda #$08 ;load bowser's palette into sprite portion of palette
sta VRAM_Buffer_AddrCtrl
ChainObj:
ldy $00 ;get value loaded earlier from decoder
ldx C_ObjectRow-2,y ;get appropriate row and metatile for object
lda C_ObjectMetatile-2,y
jmp ColObj
EmptyBlock:
jsr GetLrgObjAttrib ;get row location
ldx $07
lda #$c4
ColObj: ldy #$00 ;column length of 1
jmp RenderUnderPart
;--------------------------------
SolidBlockMetatiles:
.db $69, $61, $61, $62
BrickMetatiles:
.db $22, $51, $52, $52
.db $88 ;used only by row of bricks object
RowOfBricks:
ldy AreaType ;load area type obtained from area offset pointer
lda CloudTypeOverride ;check for cloud type override
beq DrawBricks
ldy #$04 ;if cloud type, override area type
DrawBricks: lda BrickMetatiles,y ;get appropriate metatile
jmp GetRow ;and go render it
RowOfSolidBlocks:
ldy AreaType ;load area type obtained from area offset pointer
lda SolidBlockMetatiles,y ;get metatile
GetRow: pha ;store metatile here
jsr ChkLrgObjLength ;get row number, load length
DrawRow: ldx $07
ldy #$00 ;set vertical height of 1
pla
jmp RenderUnderPart ;render object
ColumnOfBricks:
ldy AreaType ;load area type obtained from area offset
lda BrickMetatiles,y ;get metatile (no cloud override as for row)
jmp GetRow2
ColumnOfSolidBlocks:
ldy AreaType ;load area type obtained from area offset
lda SolidBlockMetatiles,y ;get metatile
GetRow2: pha ;save metatile to stack for now
jsr GetLrgObjAttrib ;get length and row
pla ;restore metatile
ldx $07 ;get starting row
jmp RenderUnderPart ;now render the column
;--------------------------------
BulletBillCannon:
jsr GetLrgObjAttrib ;get row and length of bullet bill cannon
ldx $07 ;start at first row
lda #$64 ;render bullet bill cannon
sta MetatileBuffer,x
inx
dey ;done yet?
bmi SetupCannon
lda #$65 ;if not, render middle part
sta MetatileBuffer,x
inx
dey ;done yet?
bmi SetupCannon
lda #$66 ;if not, render bottom until length expires
jsr RenderUnderPart
SetupCannon: ldx Cannon_Offset ;get offset for data used by cannons and whirlpools
jsr GetAreaObjYPosition ;get proper vertical coordinate for cannon
sta Cannon_Y_Position,x ;and store it here
lda CurrentPageLoc
sta Cannon_PageLoc,x ;store page number for cannon here
jsr GetAreaObjXPosition ;get proper horizontal coordinate for cannon
sta Cannon_X_Position,x ;and store it here
inx
cpx #$06 ;increment and check offset
bcc StrCOffset ;if not yet reached sixth cannon, branch to save offset
ldx #$00 ;otherwise initialize it
StrCOffset: stx Cannon_Offset ;save new offset and leave
rts
;--------------------------------
StaircaseHeightData:
.db $07, $07, $06, $05, $04, $03, $02, $01, $00
StaircaseRowData:
.db $03, $03, $04, $05, $06, $07, $08, $09, $0a
StaircaseObject:
jsr ChkLrgObjLength ;check and load length
bcc NextStair ;if length already loaded, skip init part
lda #$09 ;start past the end for the bottom
sta StaircaseControl ;of the staircase
NextStair: dec StaircaseControl ;move onto next step (or first if starting)
ldy StaircaseControl
ldx StaircaseRowData,y ;get starting row and height to render
lda StaircaseHeightData,y
tay
lda #$61 ;now render solid block staircase
jmp RenderUnderPart
;--------------------------------
Jumpspring:
jsr GetLrgObjAttrib
jsr FindEmptyEnemySlot ;find empty space in enemy object buffer
jsr GetAreaObjXPosition ;get horizontal coordinate for jumpspring
sta Enemy_X_Position,x ;and store
lda CurrentPageLoc ;store page location of jumpspring
sta Enemy_PageLoc,x
jsr GetAreaObjYPosition ;get vertical coordinate for jumpspring
sta Enemy_Y_Position,x ;and store
sta Jumpspring_FixedYPos,x ;store as permanent coordinate here
lda #JumpspringObject
sta Enemy_ID,x ;write jumpspring object to enemy object buffer
ldy #$01
sty Enemy_Y_HighPos,x ;store vertical high byte
inc Enemy_Flag,x ;set flag for enemy object buffer
ldx $07
lda #$67 ;draw metatiles in two rows where jumpspring is
sta MetatileBuffer,x
lda #$68
sta MetatileBuffer+1,x
rts
;--------------------------------
;$07 - used to save ID of brick object
Hidden1UpBlock:
lda Hidden1UpFlag ;if flag not set, do not render object
beq ExitDecBlock
lda #$00 ;if set, init for the next one
sta Hidden1UpFlag
jmp BrickWithItem ;jump to code shared with unbreakable bricks
QuestionBlock:
jsr GetAreaObjectID ;get value from level decoder routine
jmp DrawQBlk ;go to render it
BrickWithCoins:
lda #$00 ;initialize multi-coin timer flag
sta BrickCoinTimerFlag
BrickWithItem:
jsr GetAreaObjectID ;save area object ID
sty $07
lda #$00 ;load default adder for bricks with lines
ldy AreaType ;check level type for ground level
dey
beq BWithL ;if ground type, do not start with 5
lda #$05 ;otherwise use adder for bricks without lines
BWithL: clc ;add object ID to adder
adc $07
tay ;use as offset for metatile
DrawQBlk: lda BrickQBlockMetatiles,y ;get appropriate metatile for brick (question block
pha ;if branched to here from question block routine)
jsr GetLrgObjAttrib ;get row from location byte
jmp DrawRow ;now render the object
GetAreaObjectID:
lda $00 ;get value saved from area parser routine
sec
sbc #$00 ;possibly residual code
tay ;save to Y
ExitDecBlock: rts
;--------------------------------
HoleMetatiles:
.db $87, $00, $00, $00
Hole_Empty:
jsr ChkLrgObjLength ;get lower nybble and save as length
bcc NoWhirlP ;skip this part if length already loaded
lda AreaType ;check for water type level
bne NoWhirlP ;if not water type, skip this part
ldx Whirlpool_Offset ;get offset for data used by cannons and whirlpools
jsr GetAreaObjXPosition ;get proper vertical coordinate of where we're at
sec
sbc #$10 ;subtract 16 pixels
sta Whirlpool_LeftExtent,x ;store as left extent of whirlpool
lda CurrentPageLoc ;get page location of where we're at
sbc #$00 ;subtract borrow
sta Whirlpool_PageLoc,x ;save as page location of whirlpool
iny
iny ;increment length by 2
tya
asl ;multiply by 16 to get size of whirlpool
asl ;note that whirlpool will always be
asl ;two blocks bigger than actual size of hole
asl ;and extend one block beyond each edge
sta Whirlpool_Length,x ;save size of whirlpool here
inx
cpx #$05 ;increment and check offset
bcc StrWOffset ;if not yet reached fifth whirlpool, branch to save offset
ldx #$00 ;otherwise initialize it
StrWOffset: stx Whirlpool_Offset ;save new offset here
NoWhirlP: ldx AreaType ;get appropriate metatile, then
lda HoleMetatiles,x ;render the hole proper
ldx #$08
ldy #$0f ;start at ninth row and go to bottom, run RenderUnderPart
;--------------------------------
RenderUnderPart:
sty AreaObjectHeight ;store vertical length to render
ldy MetatileBuffer,x ;check current spot to see if there's something
beq DrawThisRow ;we need to keep, if nothing, go ahead
cpy #$17
beq WaitOneRow ;if middle part (tree ledge), wait until next row
cpy #$1a
beq WaitOneRow ;if middle part (mushroom ledge), wait until next row
cpy #$c0
beq DrawThisRow ;if question block w/ coin, overwrite
cpy #$c0
bcs WaitOneRow ;if any other metatile with palette 3, wait until next row
cpy #$54
bne DrawThisRow ;if cracked rock terrain, overwrite
cmp #$50
beq WaitOneRow ;if stem top of mushroom, wait until next row
DrawThisRow: sta MetatileBuffer,x ;render contents of A from routine that called this
WaitOneRow: inx
cpx #$0d ;stop rendering if we're at the bottom of the screen
bcs ExitUPartR
ldy AreaObjectHeight ;decrement, and stop rendering if there is no more length
dey
bpl RenderUnderPart
ExitUPartR: rts
;--------------------------------
ChkLrgObjLength:
jsr GetLrgObjAttrib ;get row location and size (length if branched to from here)
ChkLrgObjFixedLength:
lda AreaObjectLength,x ;check for set length counter
clc ;clear carry flag for not just starting
bpl LenSet ;if counter not set, load it, otherwise leave alone
tya ;save length into length counter
sta AreaObjectLength,x
sec ;set carry flag if just starting
LenSet: rts
GetLrgObjAttrib:
ldy AreaObjOffsetBuffer,x ;get offset saved from area obj decoding routine
lda (AreaData),y ;get first byte of level object
and #%00001111
sta $07 ;save row location
iny
lda (AreaData),y ;get next byte, save lower nybble (length or height)
and #%00001111 ;as Y, then leave
tay
rts
;--------------------------------
GetAreaObjXPosition:
lda CurrentColumnPos ;multiply current offset where we're at by 16
asl ;to obtain horizontal pixel coordinate
asl
asl
asl
rts
;--------------------------------
GetAreaObjYPosition:
lda $07 ;multiply value by 16
asl
asl ;this will give us the proper vertical pixel coordinate
asl
asl
clc
adc #32 ;add 32 pixels for the status bar
rts
;-------------------------------------------------------------------------------------
;$06-$07 - used to store block buffer address used as indirect
BlockBufferAddr:
.db <Block_Buffer_1, <Block_Buffer_2
.db >Block_Buffer_1, >Block_Buffer_2
GetBlockBufferAddr:
pha ;take value of A, save
lsr ;move high nybble to low
lsr
lsr
lsr
tay ;use nybble as pointer to high byte
lda BlockBufferAddr+2,y ;of indirect here
sta $07
pla
and #%00001111 ;pull from stack, mask out high nybble
clc
adc BlockBufferAddr,y ;add to low byte
sta $06 ;store here and leave
rts
;-------------------------------------------------------------------------------------
;unused space
.db $ff, $ff
;-------------------------------------------------------------------------------------
AreaDataOfsLoopback:
.db $12, $36, $0e, $0e, $0e, $32, $32, $32, $0a, $26, $40
;-------------------------------------------------------------------------------------
LoadAreaPointer:
jsr FindAreaPointer ;find it and store it here
sta AreaPointer
GetAreaType: and #%01100000 ;mask out all but d6 and d5
asl
rol
rol
rol ;make %0xx00000 into %000000xx
sta AreaType ;save 2 MSB as area type
rts
FindAreaPointer:
ldy WorldNumber ;load offset from world variable
lda WorldAddrOffsets,y
clc ;add area number used to find data
adc AreaNumber
tay
lda AreaAddrOffsets,y ;from there we have our area pointer
rts
GetAreaDataAddrs:
lda AreaPointer ;use 2 MSB for Y
jsr GetAreaType
tay
lda AreaPointer ;mask out all but 5 LSB
and #%00011111
sta AreaAddrsLOffset ;save as low offset
lda EnemyAddrHOffsets,y ;load base value with 2 altered MSB,
clc ;then add base value to 5 LSB, result
adc AreaAddrsLOffset ;becomes offset for level data
tay
lda EnemyDataAddrLow,y ;use offset to load pointer
sta EnemyDataLow
lda EnemyDataAddrHigh,y
sta EnemyDataHigh
ldy AreaType ;use area type as offset
lda AreaDataHOffsets,y ;do the same thing but with different base value
clc
adc AreaAddrsLOffset
tay
lda AreaDataAddrLow,y ;use this offset to load another pointer
sta AreaDataLow
lda AreaDataAddrHigh,y
sta AreaDataHigh
ldy #$00 ;load first byte of header
lda (AreaData),y
pha ;save it to the stack for now
and #%00000111 ;save 3 LSB for foreground scenery or bg color control
cmp #$04
bcc StoreFore
sta BackgroundColorCtrl ;if 4 or greater, save value here as bg color control
lda #$00
StoreFore: sta ForegroundScenery ;if less, save value here as foreground scenery
pla ;pull byte from stack and push it back
pha
and #%00111000 ;save player entrance control bits
lsr ;shift bits over to LSBs
lsr
lsr
sta PlayerEntranceCtrl ;save value here as player entrance control
pla ;pull byte again but do not push it back
and #%11000000 ;save 2 MSB for game timer setting
clc
rol ;rotate bits over to LSBs
rol
rol
sta GameTimerSetting ;save value here as game timer setting
iny
lda (AreaData),y ;load second byte of header
pha ;save to stack
and #%00001111 ;mask out all but lower nybble
sta TerrainControl
pla ;pull and push byte to copy it to A
pha
and #%00110000 ;save 2 MSB for background scenery type
lsr
lsr ;shift bits to LSBs
lsr
lsr
sta BackgroundScenery ;save as background scenery
pla
and #%11000000
clc
rol ;rotate bits over to LSBs
rol
rol
cmp #%00000011 ;if set to 3, store here
bne StoreStyle ;and nullify other value
sta CloudTypeOverride ;otherwise store value in other place
lda #$00
StoreStyle: sta AreaStyle
lda AreaDataLow ;increment area data address by 2 bytes
clc
adc #$02
sta AreaDataLow
lda AreaDataHigh
adc #$00
sta AreaDataHigh
rts
;-------------------------------------------------------------------------------------
;GAME LEVELS DATA
WorldAddrOffsets:
.db World1Areas-AreaAddrOffsets, World2Areas-AreaAddrOffsets
.db World3Areas-AreaAddrOffsets, World4Areas-AreaAddrOffsets
.db World5Areas-AreaAddrOffsets, World6Areas-AreaAddrOffsets
.db World7Areas-AreaAddrOffsets, World8Areas-AreaAddrOffsets
AreaAddrOffsets:
World1Areas: .db $25, $29, $c0, $26, $60
World2Areas: .db $28, $29, $01, $27, $62
World3Areas: .db $24, $35, $20, $63
World4Areas: .db $22, $29, $41, $2c, $61
World5Areas: .db $2a, $31, $26, $62
World6Areas: .db $2e, $23, $2d, $60
World7Areas: .db $33, $29, $01, $27, $64
World8Areas: .db $30, $32, $21, $65
;bonus area data offsets, included here for comparison purposes
;underground bonus area - c2
;cloud area 1 (day) - 2b
;cloud area 2 (night) - 34
;water area (5-2/6-2) - 00
;water area (8-4) - 02
;warp zone area (4-2) - 2f
EnemyAddrHOffsets:
.db $1f, $06, $1c, $00
EnemyDataAddrLow:
.db <E_CastleArea1, <E_CastleArea2, <E_CastleArea3, <E_CastleArea4, <E_CastleArea5, <E_CastleArea6
.db <E_GroundArea1, <E_GroundArea2, <E_GroundArea3, <E_GroundArea4, <E_GroundArea5, <E_GroundArea6
.db <E_GroundArea7, <E_GroundArea8, <E_GroundArea9, <E_GroundArea10, <E_GroundArea11, <E_GroundArea12
.db <E_GroundArea13, <E_GroundArea14, <E_GroundArea15, <E_GroundArea16, <E_GroundArea17, <E_GroundArea18
.db <E_GroundArea19, <E_GroundArea20, <E_GroundArea21, <E_GroundArea22, <E_UndergroundArea1
.db <E_UndergroundArea2, <E_UndergroundArea3, <E_WaterArea1, <E_WaterArea2, <E_WaterArea3
EnemyDataAddrHigh:
.db >E_CastleArea1, >E_CastleArea2, >E_CastleArea3, >E_CastleArea4, >E_CastleArea5, >E_CastleArea6
.db >E_GroundArea1, >E_GroundArea2, >E_GroundArea3, >E_GroundArea4, >E_GroundArea5, >E_GroundArea6
.db >E_GroundArea7, >E_GroundArea8, >E_GroundArea9, >E_GroundArea10, >E_GroundArea11, >E_GroundArea12
.db >E_GroundArea13, >E_GroundArea14, >E_GroundArea15, >E_GroundArea16, >E_GroundArea17, >E_GroundArea18
.db >E_GroundArea19, >E_GroundArea20, >E_GroundArea21, >E_GroundArea22, >E_UndergroundArea1
.db >E_UndergroundArea2, >E_UndergroundArea3, >E_WaterArea1, >E_WaterArea2, >E_WaterArea3
AreaDataHOffsets:
.db $00, $03, $19, $1c
AreaDataAddrLow:
.db <L_WaterArea1, <L_WaterArea2, <L_WaterArea3, <L_GroundArea1, <L_GroundArea2, <L_GroundArea3
.db <L_GroundArea4, <L_GroundArea5, <L_GroundArea6, <L_GroundArea7, <L_GroundArea8, <L_GroundArea9
.db <L_GroundArea10, <L_GroundArea11, <L_GroundArea12, <L_GroundArea13, <L_GroundArea14, <L_GroundArea15
.db <L_GroundArea16, <L_GroundArea17, <L_GroundArea18, <L_GroundArea19, <L_GroundArea20, <L_GroundArea21
.db <L_GroundArea22, <L_UndergroundArea1, <L_UndergroundArea2, <L_UndergroundArea3, <L_CastleArea1
.db <L_CastleArea2, <L_CastleArea3, <L_CastleArea4, <L_CastleArea5, <L_CastleArea6
AreaDataAddrHigh:
.db >L_WaterArea1, >L_WaterArea2, >L_WaterArea3, >L_GroundArea1, >L_GroundArea2, >L_GroundArea3
.db >L_GroundArea4, >L_GroundArea5, >L_GroundArea6, >L_GroundArea7, >L_GroundArea8, >L_GroundArea9
.db >L_GroundArea10, >L_GroundArea11, >L_GroundArea12, >L_GroundArea13, >L_GroundArea14, >L_GroundArea15
.db >L_GroundArea16, >L_GroundArea17, >L_GroundArea18, >L_GroundArea19, >L_GroundArea20, >L_GroundArea21
.db >L_GroundArea22, >L_UndergroundArea1, >L_UndergroundArea2, >L_UndergroundArea3, >L_CastleArea1
.db >L_CastleArea2, >L_CastleArea3, >L_CastleArea4, >L_CastleArea5, >L_CastleArea6
;ENEMY OBJECT DATA
;level 1-4/6-4
E_CastleArea1:
.db $76, $dd, $bb, $4c, $ea, $1d, $1b, $cc, $56, $5d
.db $16, $9d, $c6, $1d, $36, $9d, $c9, $1d, $04, $db
.db $49, $1d, $84, $1b, $c9, $5d, $88, $95, $0f, $08
.db $30, $4c, $78, $2d, $a6, $28, $90, $b5
.db $ff
;level 4-4
E_CastleArea2:
.db $0f, $03, $56, $1b, $c9, $1b, $0f, $07, $36, $1b
.db $aa, $1b, $48, $95, $0f, $0a, $2a, $1b, $5b, $0c
.db $78, $2d, $90, $b5
.db $ff
;level 2-4/5-4
E_CastleArea3:
.db $0b, $8c, $4b, $4c, $77, $5f, $eb, $0c, $bd, $db
.db $19, $9d, $75, $1d, $7d, $5b, $d9, $1d, $3d, $dd
.db $99, $1d, $26, $9d, $5a, $2b, $8a, $2c, $ca, $1b
.db $20, $95, $7b, $5c, $db, $4c, $1b, $cc, $3b, $cc
.db $78, $2d, $a6, $28, $90, $b5
.db $ff
;level 3-4
E_CastleArea4:
.db $0b, $8c, $3b, $1d, $8b, $1d, $ab, $0c, $db, $1d
.db $0f, $03, $65, $1d, $6b, $1b, $05, $9d, $0b, $1b
.db $05, $9b, $0b, $1d, $8b, $0c, $1b, $8c, $70, $15
.db $7b, $0c, $db, $0c, $0f, $08, $78, $2d, $a6, $28
.db $90, $b5
.db $ff
;level 7-4
E_CastleArea5:
.db $27, $a9, $4b, $0c, $68, $29, $0f, $06, $77, $1b
.db $0f, $0b, $60, $15, $4b, $8c, $78, $2d, $90, $b5
.db $ff
;level 8-4
E_CastleArea6:
.db $0f, $03, $8e, $65, $e1, $bb, $38, $6d, $a8, $3e, $e5, $e7
.db $0f, $08, $0b, $02, $2b, $02, $5e, $65, $e1, $bb, $0e
.db $db, $0e, $bb, $8e, $db, $0e, $fe, $65, $ec, $0f, $0d
.db $4e, $65, $e1, $0f, $0e, $4e, $02, $e0, $0f, $10, $fe, $e5, $e1
.db $1b, $85, $7b, $0c, $5b, $95, $78, $2d, $90, $b5
.db $ff
;level 3-3
E_GroundArea1:
.db $a5, $86, $e4, $28, $18, $a8, $45, $83, $69, $03
.db $c6, $29, $9b, $83, $16, $a4, $88, $24, $e9, $28
.db $05, $a8, $7b, $28, $24, $8f, $c8, $03, $e8, $03
.db $46, $a8, $85, $24, $c8, $24
.db $ff
;level 8-3
E_GroundArea2:
.db $eb, $8e, $0f, $03, $fb, $05, $17, $85, $db, $8e
.db $0f, $07, $57, $05, $7b, $05, $9b, $80, $2b, $85
.db $fb, $05, $0f, $0b, $1b, $05, $9b, $05
.db $ff
;level 4-1
E_GroundArea3:
.db $2e, $c2, $66, $e2, $11, $0f, $07, $02, $11, $0f, $0c
.db $12, $11
.db $ff
;level 6-2
E_GroundArea4:
.db $0e, $c2, $a8, $ab, $00, $bb, $8e, $6b, $82, $de, $00, $a0
.db $33, $86, $43, $06, $3e, $b4, $a0, $cb, $02, $0f, $07
.db $7e, $42, $a6, $83, $02, $0f, $0a, $3b, $02, $cb, $37
.db $0f, $0c, $e3, $0e
.db $ff
;level 3-1
E_GroundArea5:
.db $9b, $8e, $ca, $0e, $ee, $42, $44, $5b, $86, $80, $b8
.db $1b, $80, $50, $ba, $10, $b7, $5b, $00, $17, $85
.db $4b, $05, $fe, $34, $40, $b7, $86, $c6, $06, $5b, $80
.db $83, $00, $d0, $38, $5b, $8e, $8a, $0e, $a6, $00
.db $bb, $0e, $c5, $80, $f3, $00
.db $ff
;level 1-1
E_GroundArea6:
.db $1e, $c2, $00, $6b, $06, $8b, $86, $63, $b7, $0f, $05
.db $03, $06, $23, $06, $4b, $b7, $bb, $00, $5b, $b7
.db $fb, $37, $3b, $b7, $0f, $0b, $1b, $37
.db $ff
;level 1-3/5-3
E_GroundArea7:
.db $2b, $d7, $e3, $03, $c2, $86, $e2, $06, $76, $a5
.db $a3, $8f, $03, $86, $2b, $57, $68, $28, $e9, $28
.db $e5, $83, $24, $8f, $36, $a8, $5b, $03
.db $ff
;level 2-3/7-3
E_GroundArea8:
.db $0f, $02, $78, $40, $48, $ce, $f8, $c3, $f8, $c3
.db $0f, $07, $7b, $43, $c6, $d0, $0f, $8a, $c8, $50
.db $ff
;level 2-1
E_GroundArea9:
.db $85, $86, $0b, $80, $1b, $00, $db, $37, $77, $80
.db $eb, $37, $fe, $2b, $20, $2b, $80, $7b, $38, $ab, $b8
.db $77, $86, $fe, $42, $20, $49, $86, $8b, $06, $9b, $80
.db $7b, $8e, $5b, $b7, $9b, $0e, $bb, $0e, $9b, $80
;end of data terminator here is also used by pipe intro area
E_GroundArea10:
.db $ff
;level 5-1
E_GroundArea11:
.db $0b, $80, $60, $38, $10, $b8, $c0, $3b, $db, $8e
.db $40, $b8, $f0, $38, $7b, $8e, $a0, $b8, $c0, $b8
.db $fb, $00, $a0, $b8, $30, $bb, $ee, $42, $88, $0f, $0b
.db $2b, $0e, $67, $0e
.db $ff
;cloud level used in levels 2-1 and 5-2
E_GroundArea12:
.db $0a, $aa, $0e, $28, $2a, $0e, $31, $88
.db $ff
;level 4-3
E_GroundArea13:
.db $c7, $83, $d7, $03, $42, $8f, $7a, $03, $05, $a4
.db $78, $24, $a6, $25, $e4, $25, $4b, $83, $e3, $03
.db $05, $a4, $89, $24, $b5, $24, $09, $a4, $65, $24
.db $c9, $24, $0f, $08, $85, $25
.db $ff
;level 6-3
E_GroundArea14:
.db $cd, $a5, $b5, $a8, $07, $a8, $76, $28, $cc, $25
.db $65, $a4, $a9, $24, $e5, $24, $19, $a4, $0f, $07
.db $95, $28, $e6, $24, $19, $a4, $d7, $29, $16, $a9
.db $58, $29, $97, $29
.db $ff
;level 6-1
E_GroundArea15:
.db $0f, $02, $02, $11, $0f, $07, $02, $11
.db $ff
;warp zone area used in level 4-2
E_GroundArea16:
.db $ff
;level 8-1
E_GroundArea17:
.db $2b, $82, $ab, $38, $de, $42, $e2, $1b, $b8, $eb
.db $3b, $db, $80, $8b, $b8, $1b, $82, $fb, $b8, $7b
.db $80, $fb, $3c, $5b, $bc, $7b, $b8, $1b, $8e, $cb
.db $0e, $1b, $8e, $0f, $0d, $2b, $3b, $bb, $b8, $eb, $82
.db $4b, $b8, $bb, $38, $3b, $b7, $bb, $02, $0f, $13
.db $1b, $00, $cb, $80, $6b, $bc
.db $ff
;level 5-2
E_GroundArea18:
.db $7b, $80, $ae, $00, $80, $8b, $8e, $e8, $05, $f9, $86
.db $17, $86, $16, $85, $4e, $2b, $80, $ab, $8e, $87, $85
.db $c3, $05, $8b, $82, $9b, $02, $ab, $02, $bb, $86
.db $cb, $06, $d3, $03, $3b, $8e, $6b, $0e, $a7, $8e
.db $ff
;level 8-2
E_GroundArea19:
.db $29, $8e, $52, $11, $83, $0e, $0f, $03, $9b, $0e
.db $2b, $8e, $5b, $0e, $cb, $8e, $fb, $0e, $fb, $82
.db $9b, $82, $bb, $02, $fe, $42, $e8, $bb, $8e, $0f, $0a
.db $ab, $0e, $cb, $0e, $f9, $0e, $88, $86, $a6, $06
.db $db, $02, $b6, $8e
.db $ff
;level 7-1
E_GroundArea20:
.db $ab, $ce, $de, $42, $c0, $cb, $ce, $5b, $8e, $1b, $ce
.db $4b, $85, $67, $45, $0f, $07, $2b, $00, $7b, $85
.db $97, $05, $0f, $0a, $92, $02
.db $ff
;cloud level used in levels 3-1 and 6-2
E_GroundArea21:
.db $0a, $aa, $0e, $24, $4a, $1e, $23, $aa
.db $ff
;level 3-2
E_GroundArea22:
.db $1b, $80, $bb, $38, $4b, $bc, $eb, $3b, $0f, $04
.db $2b, $00, $ab, $38, $eb, $00, $cb, $8e, $fb, $80
.db $ab, $b8, $6b, $80, $fb, $3c, $9b, $bb, $5b, $bc
.db $fb, $00, $6b, $b8, $fb, $38
.db $ff
;level 1-2
E_UndergroundArea1:
.db $0b, $86, $1a, $06, $db, $06, $de, $c2, $02, $f0, $3b
.db $bb, $80, $eb, $06, $0b, $86, $93, $06, $f0, $39
.db $0f, $06, $60, $b8, $1b, $86, $a0, $b9, $b7, $27
.db $bd, $27, $2b, $83, $a1, $26, $a9, $26, $ee, $25, $0b
.db $27, $b4
.db $ff
;level 4-2
E_UndergroundArea2:
.db $0f, $02, $1e, $2f, $60, $e0, $3a, $a5, $a7, $db, $80
.db $3b, $82, $8b, $02, $fe, $42, $68, $70, $bb, $25, $a7
.db $2c, $27, $b2, $26, $b9, $26, $9b, $80, $a8, $82
.db $b5, $27, $bc, $27, $b0, $bb, $3b, $82, $87, $34
.db $ee, $25, $6b
.db $ff
;underground bonus rooms area used in many levels
E_UndergroundArea3:
.db $1e, $a5, $0a, $2e, $28, $27, $2e, $33, $c7, $0f, $03, $1e, $40, $07
.db $2e, $30, $e7, $0f, $05, $1e, $24, $44, $0f, $07, $1e, $22, $6a
.db $2e, $23, $ab, $0f, $09, $1e, $41, $68, $1e, $2a, $8a, $2e, $23, $a2
.db $2e, $32, $ea
.db $ff
;water area used in levels 5-2 and 6-2
E_WaterArea1:
.db $3b, $87, $66, $27, $cc, $27, $ee, $31, $87, $ee, $23, $a7
.db $3b, $87, $db, $07
.db $ff
;level 2-2/7-2
E_WaterArea2:
.db $0f, $01, $2e, $25, $2b, $2e, $25, $4b, $4e, $25, $cb, $6b, $07
.db $97, $47, $e9, $87, $47, $c7, $7a, $07, $d6, $c7
.db $78, $07, $38, $87, $ab, $47, $e3, $07, $9b, $87
.db $0f, $09, $68, $47, $db, $c7, $3b, $c7
.db $ff
;water area used in level 8-4
E_WaterArea3:
.db $47, $9b, $cb, $07, $fa, $1d, $86, $9b, $3a, $87
.db $56, $07, $88, $1b, $07, $9d, $2e, $65, $f0
.db $ff
;AREA OBJECT DATA
;level 1-4/6-4
L_CastleArea1:
.db $9b, $07
.db $05, $32, $06, $33, $07, $34, $ce, $03, $dc, $51
.db $ee, $07, $73, $e0, $74, $0a, $7e, $06, $9e, $0a
.db $ce, $06, $e4, $00, $e8, $0a, $fe, $0a, $2e, $89
.db $4e, $0b, $54, $0a, $14, $8a, $c4, $0a, $34, $8a
.db $7e, $06, $c7, $0a, $01, $e0, $02, $0a, $47, $0a
.db $81, $60, $82, $0a, $c7, $0a, $0e, $87, $7e, $02
.db $a7, $02, $b3, $02, $d7, $02, $e3, $02, $07, $82
.db $13, $02, $3e, $06, $7e, $02, $ae, $07, $fe, $0a
.db $0d, $c4, $cd, $43, $ce, $09, $de, $0b, $dd, $42
.db $fe, $02, $5d, $c7
.db $fd
;level 4-4
L_CastleArea2:
.db $5b, $07
.db $05, $32, $06, $33, $07, $34, $5e, $0a, $68, $64
.db $98, $64, $a8, $64, $ce, $06, $fe, $02, $0d, $01
.db $1e, $0e, $7e, $02, $94, $63, $b4, $63, $d4, $63
.db $f4, $63, $14, $e3, $2e, $0e, $5e, $02, $64, $35
.db $88, $72, $be, $0e, $0d, $04, $ae, $02, $ce, $08
.db $cd, $4b, $fe, $02, $0d, $05, $68, $31, $7e, $0a
.db $96, $31, $a9, $63, $a8, $33, $d5, $30, $ee, $02
.db $e6, $62, $f4, $61, $04, $b1, $08, $3f, $44, $33
.db $94, $63, $a4, $31, $e4, $31, $04, $bf, $08, $3f
.db $04, $bf, $08, $3f, $cd, $4b, $03, $e4, $0e, $03
.db $2e, $01, $7e, $06, $be, $02, $de, $06, $fe, $0a
.db $0d, $c4, $cd, $43, $ce, $09, $de, $0b, $dd, $42
.db $fe, $02, $5d, $c7
.db $fd
;level 2-4/5-4
L_CastleArea3:
.db $9b, $07
.db $05, $32, $06, $33, $07, $34, $fe, $00, $27, $b1
.db $65, $32, $75, $0a, $71, $00, $b7, $31, $08, $e4
.db $18, $64, $1e, $04, $57, $3b, $bb, $0a, $17, $8a
.db $27, $3a, $73, $0a, $7b, $0a, $d7, $0a, $e7, $3a
.db $3b, $8a, $97, $0a, $fe, $08, $24, $8a, $2e, $00
.db $3e, $40, $38, $64, $6f, $00, $9f, $00, $be, $43
.db $c8, $0a, $c9, $63, $ce, $07, $fe, $07, $2e, $81
.db $66, $42, $6a, $42, $79, $0a, $be, $00, $c8, $64
.db $f8, $64, $08, $e4, $2e, $07, $7e, $03, $9e, $07
.db $be, $03, $de, $07, $fe, $0a, $03, $a5, $0d, $44
.db $cd, $43, $ce, $09, $dd, $42, $de, $0b, $fe, $02
.db $5d, $c7
.db $fd
;level 3-4
L_CastleArea4:
.db $9b, $07
.db $05, $32, $06, $33, $07, $34, $fe, $06, $0c, $81
.db $39, $0a, $5c, $01, $89, $0a, $ac, $01, $d9, $0a
.db $fc, $01, $2e, $83, $a7, $01, $b7, $00, $c7, $01
.db $de, $0a, $fe, $02, $4e, $83, $5a, $32, $63, $0a
.db $69, $0a, $7e, $02, $ee, $03, $fa, $32, $03, $8a
.db $09, $0a, $1e, $02, $ee, $03, $fa, $32, $03, $8a
.db $09, $0a, $14, $42, $1e, $02, $7e, $0a, $9e, $07
.db $fe, $0a, $2e, $86, $5e, $0a, $8e, $06, $be, $0a
.db $ee, $07, $3e, $83, $5e, $07, $fe, $0a, $0d, $c4
.db $41, $52, $51, $52, $cd, $43, $ce, $09, $de, $0b
.db $dd, $42, $fe, $02, $5d, $c7
.db $fd
;level 7-4
L_CastleArea5:
.db $5b, $07
.db $05, $32, $06, $33, $07, $34, $fe, $0a, $ae, $86
.db $be, $07, $fe, $02, $0d, $02, $27, $32, $46, $61
.db $55, $62, $5e, $0e, $1e, $82, $68, $3c, $74, $3a
.db $7d, $4b, $5e, $8e, $7d, $4b, $7e, $82, $84, $62
.db $94, $61, $a4, $31, $bd, $4b, $ce, $06, $fe, $02
.db $0d, $06, $34, $31, $3e, $0a, $64, $32, $75, $0a
.db $7b, $61, $a4, $33, $ae, $02, $de, $0e, $3e, $82
.db $64, $32, $78, $32, $b4, $36, $c8, $36, $dd, $4b
.db $44, $b2, $58, $32, $94, $63, $a4, $3e, $ba, $30
.db $c9, $61, $ce, $06, $dd, $4b, $ce, $86, $dd, $4b
.db $fe, $02, $2e, $86, $5e, $02, $7e, $06, $fe, $02
.db $1e, $86, $3e, $02, $5e, $06, $7e, $02, $9e, $06
.db $fe, $0a, $0d, $c4, $cd, $43, $ce, $09, $de, $0b
.db $dd, $42, $fe, $02, $5d, $c7
.db $fd
;level 8-4
L_CastleArea6:
.db $5b, $06
.db $05, $32, $06, $33, $07, $34, $5e, $0a, $ae, $02
.db $0d, $01, $39, $73, $0d, $03, $39, $7b, $4d, $4b
.db $de, $06, $1e, $8a, $ae, $06, $c4, $33, $16, $fe
.db $a5, $77, $fe, $02, $fe, $82, $0d, $07, $39, $73
.db $a8, $74, $ed, $4b, $49, $fb, $e8, $74, $fe, $0a
.db $2e, $82, $67, $02, $84, $7a, $87, $31, $0d, $0b
.db $fe, $02, $0d, $0c, $39, $73, $5e, $06, $c6, $76
.db $45, $ff, $be, $0a, $dd, $48, $fe, $06, $3d, $cb
.db $46, $7e, $ad, $4a, $fe, $82, $39, $f3, $a9, $7b
.db $4e, $8a, $9e, $07, $fe, $0a, $0d, $c4, $cd, $43
.db $ce, $09, $de, $0b, $dd, $42, $fe, $02, $5d, $c7
.db $fd
;level 3-3
L_GroundArea1:
.db $94, $11
.db $0f, $26, $fe, $10, $28, $94, $65, $15, $eb, $12
.db $fa, $41, $4a, $96, $54, $40, $a4, $42, $b7, $13
.db $e9, $19, $f5, $15, $11, $80, $47, $42, $71, $13
.db $80, $41, $15, $92, $1b, $1f, $24, $40, $55, $12
.db $64, $40, $95, $12, $a4, $40, $d2, $12, $e1, $40
.db $13, $c0, $2c, $17, $2f, $12, $49, $13, $83, $40
.db $9f, $14, $a3, $40, $17, $92, $83, $13, $92, $41
.db $b9, $14, $c5, $12, $c8, $40, $d4, $40, $4b, $92
.db $78, $1b, $9c, $94, $9f, $11, $df, $14, $fe, $11
.db $7d, $c1, $9e, $42, $cf, $20
.db $fd
;level 8-3
L_GroundArea2:
.db $90, $b1
.db $0f, $26, $29, $91, $7e, $42, $fe, $40, $28, $92
.db $4e, $42, $2e, $c0, $57, $73, $c3, $25, $c7, $27
.db $23, $84, $33, $20, $5c, $01, $77, $63, $88, $62
.db $99, $61, $aa, $60, $bc, $01, $ee, $42, $4e, $c0
.db $69, $11, $7e, $42, $de, $40, $f8, $62, $0e, $c2
.db $ae, $40, $d7, $63, $e7, $63, $33, $a7, $37, $27
.db $43, $04, $cc, $01, $e7, $73, $0c, $81, $3e, $42
.db $0d, $0a, $5e, $40, $88, $72, $be, $42, $e7, $87
.db $fe, $40, $39, $e1, $4e, $00, $69, $60, $87, $60
.db $a5, $60, $c3, $31, $fe, $31, $6d, $c1, $be, $42
.db $ef, $20
.db $fd
;level 4-1
L_GroundArea3:
.db $52, $21
.db $0f, $20, $6e, $40, $58, $f2, $93, $01, $97, $00
.db $0c, $81, $97, $40, $a6, $41, $c7, $40, $0d, $04
.db $03, $01, $07, $01, $23, $01, $27, $01, $ec, $03
.db $ac, $f3, $c3, $03, $78, $e2, $94, $43, $47, $f3
.db $74, $43, $47, $fb, $74, $43, $2c, $f1, $4c, $63
.db $47, $00, $57, $21, $5c, $01, $7c, $72, $39, $f1
.db $ec, $02, $4c, $81, $d8, $62, $ec, $01, $0d, $0d
.db $0f, $38, $c7, $07, $ed, $4a, $1d, $c1, $5f, $26
.db $fd
;level 6-2
L_GroundArea4:
.db $54, $21
.db $0f, $26, $a7, $22, $37, $fb, $73, $20, $83, $07
.db $87, $02, $93, $20, $c7, $73, $04, $f1, $06, $31
.db $39, $71, $59, $71, $e7, $73, $37, $a0, $47, $04
.db $86, $7c, $e5, $71, $e7, $31, $33, $a4, $39, $71
.db $a9, $71, $d3, $23, $08, $f2, $13, $05, $27, $02
.db $49, $71, $75, $75, $e8, $72, $67, $f3, $99, $71
.db $e7, $20, $f4, $72, $f7, $31, $17, $a0, $33, $20
.db $39, $71, $73, $28, $bc, $05, $39, $f1, $79, $71
.db $a6, $21, $c3, $06, $d3, $20, $dc, $00, $fc, $00
.db $07, $a2, $13, $21, $5f, $32, $8c, $00, $98, $7a
.db $c7, $63, $d9, $61, $03, $a2, $07, $22, $74, $72
.db $77, $31, $e7, $73, $39, $f1, $58, $72, $77, $73
.db $d8, $72, $7f, $b1, $97, $73, $b6, $64, $c5, $65
.db $d4, $66, $e3, $67, $f3, $67, $8d, $c1, $cf, $26
.db $fd
;level 3-1
L_GroundArea5:
.db $52, $31
.db $0f, $20, $6e, $66, $07, $81, $36, $01, $66, $00
.db $a7, $22, $08, $f2, $67, $7b, $dc, $02, $98, $f2
.db $d7, $20, $39, $f1, $9f, $33, $dc, $27, $dc, $57
.db $23, $83, $57, $63, $6c, $51, $87, $63, $99, $61
.db $a3, $06, $b3, $21, $77, $f3, $f3, $21, $f7, $2a
.db $13, $81, $23, $22, $53, $00, $63, $22, $e9, $0b
.db $0c, $83, $13, $21, $16, $22, $33, $05, $8f, $35
.db $ec, $01, $63, $a0, $67, $20, $73, $01, $77, $01
.db $83, $20, $87, $20, $b3, $20, $b7, $20, $c3, $01
.db $c7, $00, $d3, $20, $d7, $20, $67, $a0, $77, $07
.db $87, $22, $e8, $62, $f5, $65, $1c, $82, $7f, $38
.db $8d, $c1, $cf, $26
.db $fd
;level 1-1
L_GroundArea6:
.db $50, $21
.db $07, $81, $47, $24, $57, $00, $63, $01, $77, $01
.db $c9, $71, $68, $f2, $e7, $73, $97, $fb, $06, $83
.db $5c, $01, $d7, $22, $e7, $00, $03, $a7, $6c, $02
.db $b3, $22, $e3, $01, $e7, $07, $47, $a0, $57, $06
.db $a7, $01, $d3, $00, $d7, $01, $07, $81, $67, $20
.db $93, $22, $03, $a3, $1c, $61, $17, $21, $6f, $33
.db $c7, $63, $d8, $62, $e9, $61, $fa, $60, $4f, $b3
.db $87, $63, $9c, $01, $b7, $63, $c8, $62, $d9, $61
.db $ea, $60, $39, $f1, $87, $21, $a7, $01, $b7, $20
.db $39, $f1, $5f, $38, $6d, $c1, $af, $26
.db $fd
;level 1-3/5-3
L_GroundArea7:
.db $90, $11
.db $0f, $26, $fe, $10, $2a, $93, $87, $17, $a3, $14
.db $b2, $42, $0a, $92, $19, $40, $36, $14, $50, $41
.db $82, $16, $2b, $93, $24, $41, $bb, $14, $b8, $00
.db $c2, $43, $c3, $13, $1b, $94, $67, $12, $c4, $15
.db $53, $c1, $d2, $41, $12, $c1, $29, $13, $85, $17
.db $1b, $92, $1a, $42, $47, $13, $83, $41, $a7, $13
.db $0e, $91, $a7, $63, $b7, $63, $c5, $65, $d5, $65
.db $dd, $4a, $e3, $67, $f3, $67, $8d, $c1, $ae, $42
.db $df, $20
.db $fd
;level 2-3/7-3
L_GroundArea8:
.db $90, $11
.db $0f, $26, $6e, $10, $8b, $17, $af, $32, $d8, $62
.db $e8, $62, $fc, $3f, $ad, $c8, $f8, $64, $0c, $be
.db $43, $43, $f8, $64, $0c, $bf, $73, $40, $84, $40
.db $93, $40, $a4, $40, $b3, $40, $f8, $64, $48, $e4
.db $5c, $39, $83, $40, $92, $41, $b3, $40, $f8, $64
.db $48, $e4, $5c, $39, $f8, $64, $13, $c2, $37, $65
.db $4c, $24, $63, $00, $97, $65, $c3, $42, $0b, $97
.db $ac, $32, $f8, $64, $0c, $be, $53, $45, $9d, $48
.db $f8, $64, $2a, $e2, $3c, $47, $56, $43, $ba, $62
.db $f8, $64, $0c, $b7, $88, $64, $bc, $31, $d4, $45
.db $fc, $31, $3c, $b1, $78, $64, $8c, $38, $0b, $9c
.db $1a, $33, $18, $61, $28, $61, $39, $60, $5d, $4a
.db $ee, $11, $0f, $b8, $1d, $c1, $3e, $42, $6f, $20
.db $fd
;level 2-1
L_GroundArea9:
.db $52, $31
.db $0f, $20, $6e, $40, $f7, $20, $07, $84, $17, $20
.db $4f, $34, $c3, $03, $c7, $02, $d3, $22, $27, $e3
.db $39, $61, $e7, $73, $5c, $e4, $57, $00, $6c, $73
.db $47, $a0, $53, $06, $63, $22, $a7, $73, $fc, $73
.db $13, $a1, $33, $05, $43, $21, $5c, $72, $c3, $23
.db $cc, $03, $77, $fb, $ac, $02, $39, $f1, $a7, $73
.db $d3, $04, $e8, $72, $e3, $22, $26, $f4, $bc, $02
.db $8c, $81, $a8, $62, $17, $87, $43, $24, $a7, $01
.db $c3, $04, $08, $f2, $97, $21, $a3, $02, $c9, $0b
.db $e1, $69, $f1, $69, $8d, $c1, $cf, $26
.db $fd
;pipe intro area
L_GroundArea10:
.db $38, $11
.db $0f, $26, $ad, $40, $3d, $c7
.db $fd
;level 5-1
L_GroundArea11:
.db $95, $b1
.db $0f, $26, $0d, $02, $c8, $72, $1c, $81, $38, $72
.db $0d, $05, $97, $34, $98, $62, $a3, $20, $b3, $06
.db $c3, $20, $cc, $03, $f9, $91, $2c, $81, $48, $62
.db $0d, $09, $37, $63, $47, $03, $57, $21, $8c, $02
.db $c5, $79, $c7, $31, $f9, $11, $39, $f1, $a9, $11
.db $6f, $b4, $d3, $65, $e3, $65, $7d, $c1, $bf, $26
.db $fd
;cloud level used in levels 2-1 and 5-2
L_GroundArea12:
.db $00, $c1
.db $4c, $00, $f4, $4f, $0d, $02, $02, $42, $43, $4f
.db $52, $c2, $de, $00, $5a, $c2, $4d, $c7
.db $fd
;level 4-3
L_GroundArea13:
.db $90, $51
.db $0f, $26, $ee, $10, $0b, $94, $33, $14, $42, $42
.db $77, $16, $86, $44, $02, $92, $4a, $16, $69, $42
.db $73, $14, $b0, $00, $c7, $12, $05, $c0, $1c, $17
.db $1f, $11, $36, $12, $8f, $14, $91, $40, $1b, $94
.db $35, $12, $34, $42, $60, $42, $61, $12, $87, $12
.db $96, $40, $a3, $14, $1c, $98, $1f, $11, $47, $12
.db $9f, $15, $cc, $15, $cf, $11, $05, $c0, $1f, $15
.db $39, $12, $7c, $16, $7f, $11, $82, $40, $98, $12
.db $df, $15, $16, $c4, $17, $14, $54, $12, $9b, $16
.db $28, $94, $ce, $01, $3d, $c1, $5e, $42, $8f, $20
.db $fd
;level 6-3
L_GroundArea14:
.db $97, $11
.db $0f, $26, $fe, $10, $2b, $92, $57, $12, $8b, $12
.db $c0, $41, $f7, $13, $5b, $92, $69, $0b, $bb, $12
.db $b2, $46, $19, $93, $71, $00, $17, $94, $7c, $14
.db $7f, $11, $93, $41, $bf, $15, $fc, $13, $ff, $11
.db $2f, $95, $50, $42, $51, $12, $58, $14, $a6, $12
.db $db, $12, $1b, $93, $46, $43, $7b, $12, $8d, $49
.db $b7, $14, $1b, $94, $49, $0b, $bb, $12, $fc, $13
.db $ff, $12, $03, $c1, $2f, $15, $43, $12, $4b, $13
.db $77, $13, $9d, $4a, $15, $c1, $a1, $41, $c3, $12
.db $fe, $01, $7d, $c1, $9e, $42, $cf, $20
.db $fd
;level 6-1
L_GroundArea15:
.db $52, $21
.db $0f, $20, $6e, $44, $0c, $f1, $4c, $01, $aa, $35
.db $d9, $34, $ee, $20, $08, $b3, $37, $32, $43, $04
.db $4e, $21, $53, $20, $7c, $01, $97, $21, $b7, $07
.db $9c, $81, $e7, $42, $5f, $b3, $97, $63, $ac, $02
.db $c5, $41, $49, $e0, $58, $61, $76, $64, $85, $65
.db $94, $66, $a4, $22, $a6, $03, $c8, $22, $dc, $02
.db $68, $f2, $96, $42, $13, $82, $17, $02, $af, $34
.db $f6, $21, $fc, $06, $26, $80, $2a, $24, $36, $01
.db $8c, $00, $ff, $35, $4e, $a0, $55, $21, $77, $20
.db $87, $07, $89, $22, $ae, $21, $4c, $82, $9f, $34
.db $ec, $01, $03, $e7, $13, $67, $8d, $4a, $ad, $41
.db $0f, $a6
.db $fd
;warp zone area used in level 4-2
L_GroundArea16:
.db $10, $51
.db $4c, $00, $c7, $12, $c6, $42, $03, $92, $02, $42
.db $29, $12, $63, $12, $62, $42, $69, $14, $a5, $12
.db $a4, $42, $e2, $14, $e1, $44, $f8, $16, $37, $c1
.db $8f, $38, $02, $bb, $28, $7a, $68, $7a, $a8, $7a
.db $e0, $6a, $f0, $6a, $6d, $c5
.db $fd
;level 8-1
L_GroundArea17:
.db $92, $31
.db $0f, $20, $6e, $40, $0d, $02, $37, $73, $ec, $00
.db $0c, $80, $3c, $00, $6c, $00, $9c, $00, $06, $c0
.db $c7, $73, $06, $83, $28, $72, $96, $40, $e7, $73
.db $26, $c0, $87, $7b, $d2, $41, $39, $f1, $c8, $f2
.db $97, $e3, $a3, $23, $e7, $02, $e3, $07, $f3, $22
.db $37, $e3, $9c, $00, $bc, $00, $ec, $00, $0c, $80
.db $3c, $00, $86, $21, $a6, $06, $b6, $24, $5c, $80
.db $7c, $00, $9c, $00, $29, $e1, $dc, $05, $f6, $41
.db $dc, $80, $e8, $72, $0c, $81, $27, $73, $4c, $01
.db $66, $74, $0d, $11, $3f, $35, $b6, $41, $2c, $82
.db $36, $40, $7c, $02, $86, $40, $f9, $61, $39, $e1
.db $ac, $04, $c6, $41, $0c, $83, $16, $41, $88, $f2
.db $39, $f1, $7c, $00, $89, $61, $9c, $00, $a7, $63
.db $bc, $00, $c5, $65, $dc, $00, $e3, $67, $f3, $67
.db $8d, $c1, $cf, $26
.db $fd
;level 5-2
L_GroundArea18:
.db $55, $b1
.db $0f, $26, $cf, $33, $07, $b2, $15, $11, $52, $42
.db $99, $0b, $ac, $02, $d3, $24, $d6, $42, $d7, $25
.db $23, $84, $cf, $33, $07, $e3, $19, $61, $78, $7a
.db $ef, $33, $2c, $81, $46, $64, $55, $65, $65, $65
.db $ec, $74, $47, $82, $53, $05, $63, $21, $62, $41
.db $96, $22, $9a, $41, $cc, $03, $b9, $91, $39, $f1
.db $63, $26, $67, $27, $d3, $06, $fc, $01, $18, $e2
.db $d9, $07, $e9, $04, $0c, $86, $37, $22, $93, $24
.db $87, $84, $ac, $02, $c2, $41, $c3, $23, $d9, $71
.db $fc, $01, $7f, $b1, $9c, $00, $a7, $63, $b6, $64
.db $cc, $00, $d4, $66, $e3, $67, $f3, $67, $8d, $c1
.db $cf, $26
.db $fd
;level 8-2
L_GroundArea19:
.db $50, $b1
.db $0f, $26, $fc, $00, $1f, $b3, $5c, $00, $65, $65
.db $74, $66, $83, $67, $93, $67, $dc, $73, $4c, $80
.db $b3, $20, $c9, $0b, $c3, $08, $d3, $2f, $dc, $00
.db $2c, $80, $4c, $00, $8c, $00, $d3, $2e, $ed, $4a
.db $fc, $00, $d7, $a1, $ec, $01, $4c, $80, $59, $11
.db $d8, $11, $da, $10, $37, $a0, $47, $04, $99, $11
.db $e7, $21, $3a, $90, $67, $20, $76, $10, $77, $60
.db $87, $07, $d8, $12, $39, $f1, $ac, $00, $e9, $71
.db $0c, $80, $2c, $00, $4c, $05, $c7, $7b, $39, $f1
.db $ec, $00, $f9, $11, $0c, $82, $6f, $34, $f8, $11
.db $fa, $10, $7f, $b2, $ac, $00, $b6, $64, $cc, $01
.db $e3, $67, $f3, $67, $8d, $c1, $cf, $26
.db $fd
;level 7-1
L_GroundArea20:
.db $52, $b1
.db $0f, $20, $6e, $45, $39, $91, $b3, $04, $c3, $21
.db $c8, $11, $ca, $10, $49, $91, $7c, $73, $e8, $12
.db $88, $91, $8a, $10, $e7, $21, $05, $91, $07, $30
.db $17, $07, $27, $20, $49, $11, $9c, $01, $c8, $72
.db $23, $a6, $27, $26, $d3, $03, $d8, $7a, $89, $91
.db $d8, $72, $39, $f1, $a9, $11, $09, $f1, $63, $24
.db $67, $24, $d8, $62, $28, $91, $2a, $10, $56, $21
.db $70, $04, $79, $0b, $8c, $00, $94, $21, $9f, $35
.db $2f, $b8, $3d, $c1, $7f, $26
.db $fd
;cloud level used in levels 3-1 and 6-2
L_GroundArea21:
.db $06, $c1
.db $4c, $00, $f4, $4f, $0d, $02, $06, $20, $24, $4f
.db $35, $a0, $36, $20, $53, $46, $d5, $20, $d6, $20
.db $34, $a1, $73, $49, $74, $20, $94, $20, $b4, $20
.db $d4, $20, $f4, $20, $2e, $80, $59, $42, $4d, $c7
.db $fd
;level 3-2
L_GroundArea22:
.db $96, $31
.db $0f, $26, $0d, $03, $1a, $60, $77, $42, $c4, $00
.db $c8, $62, $b9, $e1, $d3, $06, $d7, $07, $f9, $61
.db $0c, $81, $4e, $b1, $8e, $b1, $bc, $01, $e4, $50
.db $e9, $61, $0c, $81, $0d, $0a, $84, $43, $98, $72
.db $0d, $0c, $0f, $38, $1d, $c1, $5f, $26
.db $fd
;level 1-2
L_UndergroundArea1:
.db $48, $0f
.db $0e, $01, $5e, $02, $a7, $00, $bc, $73, $1a, $e0
.db $39, $61, $58, $62, $77, $63, $97, $63, $b8, $62
.db $d6, $07, $f8, $62, $19, $e1, $75, $52, $86, $40
.db $87, $50, $95, $52, $93, $43, $a5, $21, $c5, $52
.db $d6, $40, $d7, $20, $e5, $06, $e6, $51, $3e, $8d
.db $5e, $03, $67, $52, $77, $52, $7e, $02, $9e, $03
.db $a6, $43, $a7, $23, $de, $05, $fe, $02, $1e, $83
.db $33, $54, $46, $40, $47, $21, $56, $04, $5e, $02
.db $83, $54, $93, $52, $96, $07, $97, $50, $be, $03
.db $c7, $23, $fe, $02, $0c, $82, $43, $45, $45, $24
.db $46, $24, $90, $08, $95, $51, $78, $fa, $d7, $73
.db $39, $f1, $8c, $01, $a8, $52, $b8, $52, $cc, $01
.db $5f, $b3, $97, $63, $9e, $00, $0e, $81, $16, $24
.db $66, $04, $8e, $00, $fe, $01, $08, $d2, $0e, $06
.db $6f, $47, $9e, $0f, $0e, $82, $2d, $47, $28, $7a
.db $68, $7a, $a8, $7a, $ae, $01, $de, $0f, $6d, $c5
.db $fd
;level 4-2
L_UndergroundArea2:
.db $48, $0f
.db $0e, $01, $5e, $02, $bc, $01, $fc, $01, $2c, $82
.db $41, $52, $4e, $04, $67, $25, $68, $24, $69, $24
.db $ba, $42, $c7, $04, $de, $0b, $b2, $87, $fe, $02
.db $2c, $e1, $2c, $71, $67, $01, $77, $00, $87, $01
.db $8e, $00, $ee, $01, $f6, $02, $03, $85, $05, $02
.db $13, $21, $16, $02, $27, $02, $2e, $02, $88, $72
.db $c7, $20, $d7, $07, $e4, $76, $07, $a0, $17, $06
.db $48, $7a, $76, $20, $98, $72, $79, $e1, $88, $62
.db $9c, $01, $b7, $73, $dc, $01, $f8, $62, $fe, $01
.db $08, $e2, $0e, $00, $6e, $02, $73, $20, $77, $23
.db $83, $04, $93, $20, $ae, $00, $fe, $0a, $0e, $82
.db $39, $71, $a8, $72, $e7, $73, $0c, $81, $8f, $32
.db $ae, $00, $fe, $04, $04, $d1, $17, $04, $26, $49
.db $27, $29, $df, $33, $fe, $02, $44, $f6, $7c, $01
.db $8e, $06, $bf, $47, $ee, $0f, $4d, $c7, $0e, $82
.db $68, $7a, $ae, $01, $de, $0f, $6d, $c5
.db $fd
;underground bonus rooms area used in many levels
L_UndergroundArea3:
.db $48, $01
.db $0e, $01, $00, $5a, $3e, $06, $45, $46, $47, $46
.db $53, $44, $ae, $01, $df, $4a, $4d, $c7, $0e, $81
.db $00, $5a, $2e, $04, $37, $28, $3a, $48, $46, $47
.db $c7, $07, $ce, $0f, $df, $4a, $4d, $c7, $0e, $81
.db $00, $5a, $33, $53, $43, $51, $46, $40, $47, $50
.db $53, $04, $55, $40, $56, $50, $62, $43, $64, $40
.db $65, $50, $71, $41, $73, $51, $83, $51, $94, $40
.db $95, $50, $a3, $50, $a5, $40, $a6, $50, $b3, $51
.db $b6, $40, $b7, $50, $c3, $53, $df, $4a, $4d, $c7
.db $0e, $81, $00, $5a, $2e, $02, $36, $47, $37, $52
.db $3a, $49, $47, $25, $a7, $52, $d7, $04, $df, $4a
.db $4d, $c7, $0e, $81, $00, $5a, $3e, $02, $44, $51
.db $53, $44, $54, $44, $55, $24, $a1, $54, $ae, $01
.db $b4, $21, $df, $4a, $e5, $07, $4d, $c7
.db $fd
;water area used in levels 5-2 and 6-2
L_WaterArea1:
.db $41, $01
.db $b4, $34, $c8, $52, $f2, $51, $47, $d3, $6c, $03
.db $65, $49, $9e, $07, $be, $01, $cc, $03, $fe, $07
.db $0d, $c9, $1e, $01, $6c, $01, $62, $35, $63, $53
.db $8a, $41, $ac, $01, $b3, $53, $e9, $51, $26, $c3
.db $27, $33, $63, $43, $64, $33, $ba, $60, $c9, $61
.db $ce, $0b, $e5, $09, $ee, $0f, $7d, $ca, $7d, $47
.db $fd
;level 2-2/7-2
L_WaterArea2:
.db $41, $01
.db $b8, $52, $ea, $41, $27, $b2, $b3, $42, $16, $d4
.db $4a, $42, $a5, $51, $a7, $31, $27, $d3, $08, $e2
.db $16, $64, $2c, $04, $38, $42, $76, $64, $88, $62
.db $de, $07, $fe, $01, $0d, $c9, $23, $32, $31, $51
.db $98, $52, $0d, $c9, $59, $42, $63, $53, $67, $31
.db $14, $c2, $36, $31, $87, $53, $17, $e3, $29, $61
.db $30, $62, $3c, $08, $42, $37, $59, $40, $6a, $42
.db $99, $40, $c9, $61, $d7, $63, $39, $d1, $58, $52
.db $c3, $67, $d3, $31, $dc, $06, $f7, $42, $fa, $42
.db $23, $b1, $43, $67, $c3, $34, $c7, $34, $d1, $51
.db $43, $b3, $47, $33, $9a, $30, $a9, $61, $b8, $62
.db $be, $0b, $d5, $09, $de, $0f, $0d, $ca, $7d, $47
.db $fd
;water area used in level 8-4
L_WaterArea3:
.db $49, $0f
.db $1e, $01, $39, $73, $5e, $07, $ae, $0b, $1e, $82
.db $6e, $88, $9e, $02, $0d, $04, $2e, $0b, $45, $09
.db $4e, $0f, $ed, $47
.db $fd
;-------------------------------------------------------------------------------------
;unused space
.db $ff
;-------------------------------------------------------------------------------------
;indirect jump routine called when
;$0770 is set to 1
GameMode:
lda OperMode_Task
jsr JumpEngine
.dw InitializeArea
.dw ScreenRoutines
.dw SecondaryGameSetup
.dw GameCoreRoutine
;-------------------------------------------------------------------------------------
GameCoreRoutine:
ldx CurrentPlayer ;get which player is on the screen
lda SavedJoypadBits,x ;use appropriate player's controller bits
sta SavedJoypadBits ;as the master controller bits
jsr GameRoutines ;execute one of many possible subs
lda OperMode_Task ;check major task of operating mode
cmp #$03 ;if we are supposed to be here,
bcs GameEngine ;branch to the game engine itself
rts
GameEngine:
jsr ProcFireball_Bubble ;process fireballs and air bubbles
ldx #$00
ProcELoop: stx ObjectOffset ;put incremented offset in X as enemy object offset
jsr EnemiesAndLoopsCore ;process enemy objects
jsr FloateyNumbersRoutine ;process floatey numbers
inx
cpx #$06 ;do these two subroutines until the whole buffer is done
bne ProcELoop
jsr GetPlayerOffscreenBits ;get offscreen bits for player object
jsr RelativePlayerPosition ;get relative coordinates for player object
jsr PlayerGfxHandler ;draw the player
jsr BlockObjMT_Updater ;replace block objects with metatiles if necessary
ldx #$01
stx ObjectOffset ;set offset for second
jsr BlockObjectsCore ;process second block object
dex
stx ObjectOffset ;set offset for first
jsr BlockObjectsCore ;process first block object
jsr MiscObjectsCore ;process misc objects (hammer, jumping coins)
jsr ProcessCannons ;process bullet bill cannons
jsr ProcessWhirlpools ;process whirlpools
jsr FlagpoleRoutine ;process the flagpole
jsr RunGameTimer ;count down the game timer
jsr ColorRotation ;cycle one of the background colors
lda Player_Y_HighPos
cmp #$02 ;if player is below the screen, don't bother with the music
bpl NoChgMus
lda StarInvincibleTimer ;if star mario invincibility timer at zero,
beq ClrPlrPal ;skip this part
cmp #$04
bne NoChgMus ;if not yet at a certain point, continue
lda IntervalTimerControl ;if interval timer not yet expired,
bne NoChgMus ;branch ahead, don't bother with the music
jsr GetAreaMusic ;to re-attain appropriate level music
NoChgMus: ldy StarInvincibleTimer ;get invincibility timer
lda FrameCounter ;get frame counter
cpy #$08 ;if timer still above certain point,
bcs CycleTwo ;branch to cycle player's palette quickly
lsr ;otherwise, divide by 8 to cycle every eighth frame
lsr
CycleTwo: lsr ;if branched here, divide by 2 to cycle every other frame
jsr CyclePlayerPalette ;do sub to cycle the palette (note: shares fire flower code)
jmp SaveAB ;then skip this sub to finish up the game engine
ClrPlrPal: jsr ResetPalStar ;do sub to clear player's palette bits in attributes
SaveAB: lda A_B_Buttons ;save current A and B button
sta PreviousA_B_Buttons ;into temp variable to be used on next frame
lda #$00
sta Left_Right_Buttons ;nullify left and right buttons temp variable
UpdScrollVar: lda VRAM_Buffer_AddrCtrl
cmp #$06 ;if vram address controller set to 6 (one of two $0341s)
beq ExitEng ;then branch to leave
lda AreaParserTaskNum ;otherwise check number of tasks
bne RunParser
lda ScrollThirtyTwo ;get horizontal scroll in 0-31 or $00-$20 range
cmp #$20 ;check to see if exceeded $21
bmi ExitEng ;branch to leave if not
lda ScrollThirtyTwo
sbc #$20 ;otherwise subtract $20 to set appropriately
sta ScrollThirtyTwo ;and store
lda #$00 ;reset vram buffer offset used in conjunction with
sta VRAM_Buffer2_Offset ;level graphics buffer at $0341-$035f
RunParser: jsr AreaParserTaskHandler ;update the name table with more level graphics
ExitEng: rts ;and after all that, we're finally done!
;-------------------------------------------------------------------------------------
ScrollHandler:
lda Player_X_Scroll ;load value saved here
clc
adc Platform_X_Scroll ;add value used by left/right platforms
sta Player_X_Scroll ;save as new value here to impose force on scroll
lda ScrollLock ;check scroll lock flag
bne InitScrlAmt ;skip a bunch of code here if set
lda Player_Pos_ForScroll
cmp #$50 ;check player's horizontal screen position
bcc InitScrlAmt ;if less than 80 pixels to the right, branch
lda SideCollisionTimer ;if timer related to player's side collision
bne InitScrlAmt ;not expired, branch
ldy Player_X_Scroll ;get value and decrement by one
dey ;if value originally set to zero or otherwise
bmi InitScrlAmt ;negative for left movement, branch
iny
cpy #$02 ;if value $01, branch and do not decrement
bcc ChkNearMid
dey ;otherwise decrement by one
ChkNearMid: lda Player_Pos_ForScroll
cmp #$70 ;check player's horizontal screen position
bcc ScrollScreen ;if less than 112 pixels to the right, branch
ldy Player_X_Scroll ;otherwise get original value undecremented
ScrollScreen:
tya
sta ScrollAmount ;save value here
clc
adc ScrollThirtyTwo ;add to value already set here
sta ScrollThirtyTwo ;save as new value here
tya
clc
adc ScreenLeft_X_Pos ;add to left side coordinate
sta ScreenLeft_X_Pos ;save as new left side coordinate
sta HorizontalScroll ;save here also
lda ScreenLeft_PageLoc
adc #$00 ;add carry to page location for left
sta ScreenLeft_PageLoc ;side of the screen
and #$01 ;get LSB of page location
sta $00 ;save as temp variable for PPU register 1 mirror
lda Mirror_PPU_CTRL_REG1 ;get PPU register 1 mirror
and #%11111110 ;save all bits except d0
ora $00 ;get saved bit here and save in PPU register 1
sta Mirror_PPU_CTRL_REG1 ;mirror to be used to set name table later
jsr GetScreenPosition ;figure out where the right side is
lda #$08
sta ScrollIntervalTimer ;set scroll timer (residual, not used elsewhere)
jmp ChkPOffscr ;skip this part
InitScrlAmt: lda #$00
sta ScrollAmount ;initialize value here
ChkPOffscr: ldx #$00 ;set X for player offset
jsr GetXOffscreenBits ;get horizontal offscreen bits for player
sta $00 ;save them here
ldy #$00 ;load default offset (left side)
asl ;if d7 of offscreen bits are set,
bcs KeepOnscr ;branch with default offset
iny ;otherwise use different offset (right side)
lda $00
and #%00100000 ;check offscreen bits for d5 set
beq InitPlatScrl ;if not set, branch ahead of this part
KeepOnscr: lda ScreenEdge_X_Pos,y ;get left or right side coordinate based on offset
sec
sbc X_SubtracterData,y ;subtract amount based on offset
sta Player_X_Position ;store as player position to prevent movement further
lda ScreenEdge_PageLoc,y ;get left or right page location based on offset
sbc #$00 ;subtract borrow
sta Player_PageLoc ;save as player's page location
lda Left_Right_Buttons ;check saved controller bits
cmp OffscrJoypadBitsData,y ;against bits based on offset
beq InitPlatScrl ;if not equal, branch
lda #$00
sta Player_X_Speed ;otherwise nullify horizontal speed of player
InitPlatScrl: lda #$00 ;nullify platform force imposed on scroll
sta Platform_X_Scroll
rts
X_SubtracterData:
.db $00, $10
OffscrJoypadBitsData:
.db $01, $02
;-------------------------------------------------------------------------------------
GetScreenPosition:
lda ScreenLeft_X_Pos ;get coordinate of screen's left boundary
clc
adc #$ff ;add 255 pixels
sta ScreenRight_X_Pos ;store as coordinate of screen's right boundary
lda ScreenLeft_PageLoc ;get page number where left boundary is
adc #$00 ;add carry from before
sta ScreenRight_PageLoc ;store as page number where right boundary is
rts
;-------------------------------------------------------------------------------------
GameRoutines:
lda GameEngineSubroutine ;run routine based on number (a few of these routines are
jsr JumpEngine ;merely placeholders as conditions for other routines)
.dw Entrance_GameTimerSetup
.dw Vine_AutoClimb
.dw SideExitPipeEntry
.dw VerticalPipeEntry
.dw FlagpoleSlide
.dw PlayerEndLevel
.dw PlayerLoseLife
.dw PlayerEntrance
.dw PlayerCtrlRoutine
.dw PlayerChangeSize
.dw PlayerInjuryBlink
.dw PlayerDeath
.dw PlayerFireFlower
;-------------------------------------------------------------------------------------
PlayerEntrance:
lda AltEntranceControl ;check for mode of alternate entry
cmp #$02
beq EntrMode2 ;if found, branch to enter from pipe or with vine
lda #$00
ldy Player_Y_Position ;if vertical position above a certain
cpy #$30 ;point, nullify controller bits and continue
bcc AutoControlPlayer ;with player movement code, do not return
lda PlayerEntranceCtrl ;check player entry bits from header
cmp #$06
beq ChkBehPipe ;if set to 6 or 7, execute pipe intro code
cmp #$07 ;otherwise branch to normal entry
bne PlayerRdy
ChkBehPipe: lda Player_SprAttrib ;check for sprite attributes
bne IntroEntr ;branch if found
lda #$01
jmp AutoControlPlayer ;force player to walk to the right
IntroEntr: jsr EnterSidePipe ;execute sub to move player to the right
dec ChangeAreaTimer ;decrement timer for change of area
bne ExitEntr ;branch to exit if not yet expired
inc DisableIntermediate ;set flag to skip world and lives display
jmp NextArea ;jump to increment to next area and set modes
EntrMode2: lda JoypadOverride ;if controller override bits set here,
bne VineEntr ;branch to enter with vine
lda #$ff ;otherwise, set value here then execute sub
jsr MovePlayerYAxis ;to move player upwards (note $ff = -1)
lda Player_Y_Position ;check to see if player is at a specific coordinate
cmp #$91 ;if player risen to a certain point (this requires pipes
bcc PlayerRdy ;to be at specific height to look/function right) branch
rts ;to the last part, otherwise leave
VineEntr: lda VineHeight
cmp #$60 ;check vine height
bne ExitEntr ;if vine not yet reached maximum height, branch to leave
lda Player_Y_Position ;get player's vertical coordinate
cmp #$99 ;check player's vertical coordinate against preset value
ldy #$00 ;load default values to be written to
lda #$01 ;this value moves player to the right off the vine
bcc OffVine ;if vertical coordinate < preset value, use defaults
lda #$03
sta Player_State ;otherwise set player state to climbing
iny ;increment value in Y
lda #$08 ;set block in block buffer to cover hole, then
sta Block_Buffer_1+$b4 ;use same value to force player to climb
OffVine: sty DisableCollisionDet ;set collision detection disable flag
jsr AutoControlPlayer ;use contents of A to move player up or right, execute sub
lda Player_X_Position
cmp #$48 ;check player's horizontal position
bcc ExitEntr ;if not far enough to the right, branch to leave
PlayerRdy: lda #$08 ;set routine to be executed by game engine next frame
sta GameEngineSubroutine
lda #$01 ;set to face player to the right
sta PlayerFacingDir
lsr ;init A
sta AltEntranceControl ;init mode of entry
sta DisableCollisionDet ;init collision detection disable flag
sta JoypadOverride ;nullify controller override bits
ExitEntr: rts ;leave!
;-------------------------------------------------------------------------------------
;$07 - used to hold upper limit of high byte when player falls down hole
AutoControlPlayer:
sta SavedJoypadBits ;override controller bits with contents of A if executing here
PlayerCtrlRoutine:
lda GameEngineSubroutine ;check task here
cmp #$0b ;if certain value is set, branch to skip controller bit loading
beq SizeChk
lda AreaType ;are we in a water type area?
bne SaveJoyp ;if not, branch
ldy Player_Y_HighPos
dey ;if not in vertical area between
bne DisJoyp ;status bar and bottom, branch
lda Player_Y_Position
cmp #$d0 ;if nearing the bottom of the screen or
bcc SaveJoyp ;not in the vertical area between status bar or bottom,
DisJoyp: lda #$00 ;disable controller bits
sta SavedJoypadBits
SaveJoyp: lda SavedJoypadBits ;otherwise store A and B buttons in $0a
and #%11000000
sta A_B_Buttons
lda SavedJoypadBits ;store left and right buttons in $0c
and #%00000011
sta Left_Right_Buttons
lda SavedJoypadBits ;store up and down buttons in $0b
and #%00001100
sta Up_Down_Buttons
and #%00000100 ;check for pressing down
beq SizeChk ;if not, branch
lda Player_State ;check player's state
bne SizeChk ;if not on the ground, branch
ldy Left_Right_Buttons ;check left and right
beq SizeChk ;if neither pressed, branch
lda #$00
sta Left_Right_Buttons ;if pressing down while on the ground,
sta Up_Down_Buttons ;nullify directional bits
SizeChk: jsr PlayerMovementSubs ;run movement subroutines
ldy #$01 ;is player small?
lda PlayerSize
bne ChkMoveDir
ldy #$00 ;check for if crouching
lda CrouchingFlag
beq ChkMoveDir ;if not, branch ahead
ldy #$02 ;if big and crouching, load y with 2
ChkMoveDir: sty Player_BoundBoxCtrl ;set contents of Y as player's bounding box size control
lda #$01 ;set moving direction to right by default
ldy Player_X_Speed ;check player's horizontal speed
beq PlayerSubs ;if not moving at all horizontally, skip this part
bpl SetMoveDir ;if moving to the right, use default moving direction
asl ;otherwise change to move to the left
SetMoveDir: sta Player_MovingDir ;set moving direction
PlayerSubs: jsr ScrollHandler ;move the screen if necessary
jsr GetPlayerOffscreenBits ;get player's offscreen bits
jsr RelativePlayerPosition ;get coordinates relative to the screen
ldx #$00 ;set offset for player object
jsr BoundingBoxCore ;get player's bounding box coordinates
jsr PlayerBGCollision ;do collision detection and process
lda Player_Y_Position
cmp #$40 ;check to see if player is higher than 64th pixel
bcc PlayerHole ;if so, branch ahead
lda GameEngineSubroutine
cmp #$05 ;if running end-of-level routine, branch ahead
beq PlayerHole
cmp #$07 ;if running player entrance routine, branch ahead
beq PlayerHole
cmp #$04 ;if running routines $00-$03, branch ahead
bcc PlayerHole
lda Player_SprAttrib
and #%11011111 ;otherwise nullify player's
sta Player_SprAttrib ;background priority flag
PlayerHole: lda Player_Y_HighPos ;check player's vertical high byte
cmp #$02 ;for below the screen
bmi ExitCtrl ;branch to leave if not that far down
ldx #$01
stx ScrollLock ;set scroll lock
ldy #$04
sty $07 ;set value here
ldx #$00 ;use X as flag, and clear for cloud level
ldy GameTimerExpiredFlag ;check game timer expiration flag
bne HoleDie ;if set, branch
ldy CloudTypeOverride ;check for cloud type override
bne ChkHoleX ;skip to last part if found
HoleDie: inx ;set flag in X for player death
ldy GameEngineSubroutine
cpy #$0b ;check for some other routine running
beq ChkHoleX ;if so, branch ahead
ldy DeathMusicLoaded ;check value here
bne HoleBottom ;if already set, branch to next part
iny
sty EventMusicQueue ;otherwise play death music
sty DeathMusicLoaded ;and set value here
HoleBottom: ldy #$06
sty $07 ;change value here
ChkHoleX: cmp $07 ;compare vertical high byte with value set here
bmi ExitCtrl ;if less, branch to leave
dex ;otherwise decrement flag in X
bmi CloudExit ;if flag was clear, branch to set modes and other values
ldy EventMusicBuffer ;check to see if music is still playing
bne ExitCtrl ;branch to leave if so
lda #$06 ;otherwise set to run lose life routine
sta GameEngineSubroutine ;on next frame
ExitCtrl: rts ;leave
CloudExit:
lda #$00
sta JoypadOverride ;clear controller override bits if any are set
jsr SetEntr ;do sub to set secondary mode
inc AltEntranceControl ;set mode of entry to 3
rts
;-------------------------------------------------------------------------------------
Vine_AutoClimb:
lda Player_Y_HighPos ;check to see whether player reached position
bne AutoClimb ;above the status bar yet and if so, set modes
lda Player_Y_Position
cmp #$e4
bcc SetEntr
AutoClimb: lda #%00001000 ;set controller bits override to up
sta JoypadOverride
ldy #$03 ;set player state to climbing
sty Player_State
jmp AutoControlPlayer
SetEntr: lda #$02 ;set starting position to override
sta AltEntranceControl
jmp ChgAreaMode ;set modes
;-------------------------------------------------------------------------------------
VerticalPipeEntry:
lda #$01 ;set 1 as movement amount
jsr MovePlayerYAxis ;do sub to move player downwards
jsr ScrollHandler ;do sub to scroll screen with saved force if necessary
ldy #$00 ;load default mode of entry
lda WarpZoneControl ;check warp zone control variable/flag
bne ChgAreaPipe ;if set, branch to use mode 0
iny
lda AreaType ;check for castle level type
cmp #$03
bne ChgAreaPipe ;if not castle type level, use mode 1
iny
jmp ChgAreaPipe ;otherwise use mode 2
MovePlayerYAxis:
clc
adc Player_Y_Position ;add contents of A to player position
sta Player_Y_Position
rts
;-------------------------------------------------------------------------------------
SideExitPipeEntry:
jsr EnterSidePipe ;execute sub to move player to the right
ldy #$02
ChgAreaPipe: dec ChangeAreaTimer ;decrement timer for change of area
bne ExitCAPipe
sty AltEntranceControl ;when timer expires set mode of alternate entry
ChgAreaMode: inc DisableScreenFlag ;set flag to disable screen output
lda #$00
sta OperMode_Task ;set secondary mode of operation
sta Sprite0HitDetectFlag ;disable sprite 0 check
ExitCAPipe: rts ;leave
EnterSidePipe:
lda #$08 ;set player's horizontal speed
sta Player_X_Speed
ldy #$01 ;set controller right button by default
lda Player_X_Position ;mask out higher nybble of player's
and #%00001111 ;horizontal position
bne RightPipe
sta Player_X_Speed ;if lower nybble = 0, set as horizontal speed
tay ;and nullify controller bit override here
RightPipe: tya ;use contents of Y to
jsr AutoControlPlayer ;execute player control routine with ctrl bits nulled
rts
;-------------------------------------------------------------------------------------
PlayerChangeSize:
lda TimerControl ;check master timer control
cmp #$f8 ;for specific moment in time
bne EndChgSize ;branch if before or after that point
jmp InitChangeSize ;otherwise run code to get growing/shrinking going
EndChgSize: cmp #$c4 ;check again for another specific moment
bne ExitChgSize ;and branch to leave if before or after that point
jsr DonePlayerTask ;otherwise do sub to init timer control and set routine
ExitChgSize: rts ;and then leave
;-------------------------------------------------------------------------------------
PlayerInjuryBlink:
lda TimerControl ;check master timer control
cmp #$f0 ;for specific moment in time
bcs ExitBlink ;branch if before that point
cmp #$c8 ;check again for another specific point
beq DonePlayerTask ;branch if at that point, and not before or after
jmp PlayerCtrlRoutine ;otherwise run player control routine
ExitBlink: bne ExitBoth ;do unconditional branch to leave
InitChangeSize:
ldy PlayerChangeSizeFlag ;if growing/shrinking flag already set
bne ExitBoth ;then branch to leave
sty PlayerAnimCtrl ;otherwise initialize player's animation frame control
inc PlayerChangeSizeFlag ;set growing/shrinking flag
lda PlayerSize
eor #$01 ;invert player's size
sta PlayerSize
ExitBoth: rts ;leave
;-------------------------------------------------------------------------------------
;$00 - used in CyclePlayerPalette to store current palette to cycle
PlayerDeath:
lda TimerControl ;check master timer control
cmp #$f0 ;for specific moment in time
bcs ExitDeath ;branch to leave if before that point
jmp PlayerCtrlRoutine ;otherwise run player control routine
DonePlayerTask:
lda #$00
sta TimerControl ;initialize master timer control to continue timers
lda #$08
sta GameEngineSubroutine ;set player control routine to run next frame
rts ;leave
PlayerFireFlower:
lda TimerControl ;check master timer control
cmp #$c0 ;for specific moment in time
beq ResetPalFireFlower ;branch if at moment, not before or after
lda FrameCounter ;get frame counter
lsr
lsr ;divide by four to change every four frames
CyclePlayerPalette:
and #$03 ;mask out all but d1-d0 (previously d3-d2)
sta $00 ;store result here to use as palette bits
lda Player_SprAttrib ;get player attributes
and #%11111100 ;save any other bits but palette bits
ora $00 ;add palette bits
sta Player_SprAttrib ;store as new player attributes
rts ;and leave
ResetPalFireFlower:
jsr DonePlayerTask ;do sub to init timer control and run player control routine
ResetPalStar:
lda Player_SprAttrib ;get player attributes
and #%11111100 ;mask out palette bits to force palette 0
sta Player_SprAttrib ;store as new player attributes
rts ;and leave
ExitDeath:
rts ;leave from death routine
;-------------------------------------------------------------------------------------
FlagpoleSlide:
lda Enemy_ID+5 ;check special use enemy slot
cmp #FlagpoleFlagObject ;for flagpole flag object
bne NoFPObj ;if not found, branch to something residual
lda FlagpoleSoundQueue ;load flagpole sound
sta Square1SoundQueue ;into square 1's sfx queue
lda #$00
sta FlagpoleSoundQueue ;init flagpole sound queue
ldy Player_Y_Position
cpy #$9e ;check to see if player has slid down
bcs SlidePlayer ;far enough, and if so, branch with no controller bits set
lda #$04 ;otherwise force player to climb down (to slide)
SlidePlayer: jmp AutoControlPlayer ;jump to player control routine
NoFPObj: inc GameEngineSubroutine ;increment to next routine (this may
rts ;be residual code)
;-------------------------------------------------------------------------------------
Hidden1UpCoinAmts:
.db $15, $23, $16, $1b, $17, $18, $23, $63
PlayerEndLevel:
lda #$01 ;force player to walk to the right
jsr AutoControlPlayer
lda Player_Y_Position ;check player's vertical position
cmp #$ae
bcc ChkStop ;if player is not yet off the flagpole, skip this part
lda ScrollLock ;if scroll lock not set, branch ahead to next part
beq ChkStop ;because we only need to do this part once
lda #EndOfLevelMusic
sta EventMusicQueue ;load win level music in event music queue
lda #$00
sta ScrollLock ;turn off scroll lock to skip this part later
ChkStop: lda Player_CollisionBits ;get player collision bits
lsr ;check for d0 set
bcs RdyNextA ;if d0 set, skip to next part
lda StarFlagTaskControl ;if star flag task control already set,
bne InCastle ;go ahead with the rest of the code
inc StarFlagTaskControl ;otherwise set task control now (this gets ball rolling!)
InCastle: lda #%00100000 ;set player's background priority bit to
sta Player_SprAttrib ;give illusion of being inside the castle
RdyNextA: lda StarFlagTaskControl
cmp #$05 ;if star flag task control not yet set
bne ExitNA ;beyond last valid task number, branch to leave
inc LevelNumber ;increment level number used for game logic
lda LevelNumber
cmp #$03 ;check to see if we have yet reached level -4
bne NextArea ;and skip this last part here if not
ldy WorldNumber ;get world number as offset
lda CoinTallyFor1Ups ;check third area coin tally for bonus 1-ups
cmp Hidden1UpCoinAmts,y ;against minimum value, if player has not collected
bcc NextArea ;at least this number of coins, leave flag clear
inc Hidden1UpFlag ;otherwise set hidden 1-up box control flag
NextArea: inc AreaNumber ;increment area number used for address loader
jsr LoadAreaPointer ;get new level pointer
inc FetchNewGameTimerFlag ;set flag to load new game timer
jsr ChgAreaMode ;do sub to set secondary mode, disable screen and sprite 0
sta HalfwayPage ;reset halfway page to 0 (beginning)
lda #Silence
sta EventMusicQueue ;silence music and leave
ExitNA: rts
;-------------------------------------------------------------------------------------
PlayerMovementSubs:
lda #$00 ;set A to init crouch flag by default
ldy PlayerSize ;is player small?
bne SetCrouch ;if so, branch
lda Player_State ;check state of player
bne ProcMove ;if not on the ground, branch
lda Up_Down_Buttons ;load controller bits for up and down
and #%00000100 ;single out bit for down button
SetCrouch: sta CrouchingFlag ;store value in crouch flag
ProcMove: jsr PlayerPhysicsSub ;run sub related to jumping and swimming
lda PlayerChangeSizeFlag ;if growing/shrinking flag set,
bne NoMoveSub ;branch to leave
lda Player_State
cmp #$03 ;get player state
beq MoveSubs ;if climbing, branch ahead, leave timer unset
ldy #$18
sty ClimbSideTimer ;otherwise reset timer now
MoveSubs: jsr JumpEngine
.dw OnGroundStateSub
.dw JumpSwimSub
.dw FallingSub
.dw ClimbingSub
NoMoveSub: rts
;-------------------------------------------------------------------------------------
;$00 - used by ClimbingSub to store high vertical adder
OnGroundStateSub:
jsr GetPlayerAnimSpeed ;do a sub to set animation frame timing
lda Left_Right_Buttons
beq GndMove ;if left/right controller bits not set, skip instruction
sta PlayerFacingDir ;otherwise set new facing direction
GndMove: jsr ImposeFriction ;do a sub to impose friction on player's walk/run
jsr MovePlayerHorizontally ;do another sub to move player horizontally
sta Player_X_Scroll ;set returned value as player's movement speed for scroll
rts
;--------------------------------
FallingSub:
lda VerticalForceDown
sta VerticalForce ;dump vertical movement force for falling into main one
jmp LRAir ;movement force, then skip ahead to process left/right movement
;--------------------------------
JumpSwimSub:
ldy Player_Y_Speed ;if player's vertical speed zero
bpl DumpFall ;or moving downwards, branch to falling
lda A_B_Buttons
and #A_Button ;check to see if A button is being pressed
and PreviousA_B_Buttons ;and was pressed in previous frame
bne ProcSwim ;if so, branch elsewhere
lda JumpOrigin_Y_Position ;get vertical position player jumped from
sec
sbc Player_Y_Position ;subtract current from original vertical coordinate
cmp DiffToHaltJump ;compare to value set here to see if player is in mid-jump
bcc ProcSwim ;or just starting to jump, if just starting, skip ahead
DumpFall: lda VerticalForceDown ;otherwise dump falling into main fractional
sta VerticalForce
ProcSwim: lda SwimmingFlag ;if swimming flag not set,
beq LRAir ;branch ahead to last part
jsr GetPlayerAnimSpeed ;do a sub to get animation frame timing
lda Player_Y_Position
cmp #$14 ;check vertical position against preset value
bcs LRWater ;if not yet reached a certain position, branch ahead
lda #$18
sta VerticalForce ;otherwise set fractional
LRWater: lda Left_Right_Buttons ;check left/right controller bits (check for swimming)
beq LRAir ;if not pressing any, skip
sta PlayerFacingDir ;otherwise set facing direction accordingly
LRAir: lda Left_Right_Buttons ;check left/right controller bits (check for jumping/falling)
beq JSMove ;if not pressing any, skip
jsr ImposeFriction ;otherwise process horizontal movement
JSMove: jsr MovePlayerHorizontally ;do a sub to move player horizontally
sta Player_X_Scroll ;set player's speed here, to be used for scroll later
lda GameEngineSubroutine
cmp #$0b ;check for specific routine selected
bne ExitMov1 ;branch if not set to run
lda #$28
sta VerticalForce ;otherwise set fractional
ExitMov1: jmp MovePlayerVertically ;jump to move player vertically, then leave
;--------------------------------
ClimbAdderLow:
.db $0e, $04, $fc, $f2
ClimbAdderHigh:
.db $00, $00, $ff, $ff
ClimbingSub:
lda Player_YMF_Dummy
clc ;add movement force to dummy variable
adc Player_Y_MoveForce ;save with carry
sta Player_YMF_Dummy
ldy #$00 ;set default adder here
lda Player_Y_Speed ;get player's vertical speed
bpl MoveOnVine ;if not moving upwards, branch
dey ;otherwise set adder to $ff
MoveOnVine: sty $00 ;store adder here
adc Player_Y_Position ;add carry to player's vertical position
sta Player_Y_Position ;and store to move player up or down
lda Player_Y_HighPos
adc $00 ;add carry to player's page location
sta Player_Y_HighPos ;and store
lda Left_Right_Buttons ;compare left/right controller bits
and Player_CollisionBits ;to collision flag
beq InitCSTimer ;if not set, skip to end
ldy ClimbSideTimer ;otherwise check timer
bne ExitCSub ;if timer not expired, branch to leave
ldy #$18
sty ClimbSideTimer ;otherwise set timer now
ldx #$00 ;set default offset here
ldy PlayerFacingDir ;get facing direction
lsr ;move right button controller bit to carry
bcs ClimbFD ;if controller right pressed, branch ahead
inx
inx ;otherwise increment offset by 2 bytes
ClimbFD: dey ;check to see if facing right
beq CSetFDir ;if so, branch, do not increment
inx ;otherwise increment by 1 byte
CSetFDir: lda Player_X_Position
clc ;add or subtract from player's horizontal position
adc ClimbAdderLow,x ;using value here as adder and X as offset
sta Player_X_Position
lda Player_PageLoc ;add or subtract carry or borrow using value here
adc ClimbAdderHigh,x ;from the player's page location
sta Player_PageLoc
lda Left_Right_Buttons ;get left/right controller bits again
eor #%00000011 ;invert them and store them while player
sta PlayerFacingDir ;is on vine to face player in opposite direction
ExitCSub: rts ;then leave
InitCSTimer: sta ClimbSideTimer ;initialize timer here
rts
;-------------------------------------------------------------------------------------
;$00 - used to store offset to friction data
JumpMForceData:
.db $20, $20, $1e, $28, $28, $0d, $04
FallMForceData:
.db $70, $70, $60, $90, $90, $0a, $09
PlayerYSpdData:
.db $fc, $fc, $fc, $fb, $fb, $fe, $ff
InitMForceData:
.db $00, $00, $00, $00, $00, $80, $00
MaxLeftXSpdData:
.db $d8, $e8, $f0
MaxRightXSpdData:
.db $28, $18, $10
.db $0c ;used for pipe intros
FrictionData:
.db $e4, $98, $d0
Climb_Y_SpeedData:
.db $00, $ff, $01
Climb_Y_MForceData:
.db $00, $20, $ff
PlayerPhysicsSub:
lda Player_State ;check player state
cmp #$03
bne CheckForJumping ;if not climbing, branch
ldy #$00
lda Up_Down_Buttons ;get controller bits for up/down
and Player_CollisionBits ;check against player's collision detection bits
beq ProcClimb ;if not pressing up or down, branch
iny
and #%00001000 ;check for pressing up
bne ProcClimb
iny
ProcClimb: ldx Climb_Y_MForceData,y ;load value here
stx Player_Y_MoveForce ;store as vertical movement force
lda #$08 ;load default animation timing
ldx Climb_Y_SpeedData,y ;load some other value here
stx Player_Y_Speed ;store as vertical speed
bmi SetCAnim ;if climbing down, use default animation timing value
lsr ;otherwise divide timer setting by 2
SetCAnim: sta PlayerAnimTimerSet ;store animation timer setting and leave
rts
CheckForJumping:
lda JumpspringAnimCtrl ;if jumpspring animating,
bne NoJump ;skip ahead to something else
lda A_B_Buttons ;check for A button press
and #A_Button
beq NoJump ;if not, branch to something else
and PreviousA_B_Buttons ;if button not pressed in previous frame, branch
beq ProcJumping
NoJump: jmp X_Physics ;otherwise, jump to something else
ProcJumping:
lda Player_State ;check player state
beq InitJS ;if on the ground, branch
lda SwimmingFlag ;if swimming flag not set, jump to do something else
beq NoJump ;to prevent midair jumping, otherwise continue
lda JumpSwimTimer ;if jump/swim timer nonzero, branch
bne InitJS
lda Player_Y_Speed ;check player's vertical speed
bpl InitJS ;if player's vertical speed motionless or down, branch
jmp X_Physics ;if timer at zero and player still rising, do not swim
InitJS: lda #$20 ;set jump/swim timer
sta JumpSwimTimer
ldy #$00 ;initialize vertical force and dummy variable
sty Player_YMF_Dummy
sty Player_Y_MoveForce
lda Player_Y_HighPos ;get vertical high and low bytes of jump origin
sta JumpOrigin_Y_HighPos ;and store them next to each other here
lda Player_Y_Position
sta JumpOrigin_Y_Position
lda #$01 ;set player state to jumping/swimming
sta Player_State
lda Player_XSpeedAbsolute ;check value related to walking/running speed
cmp #$09
bcc ChkWtr ;branch if below certain values, increment Y
iny ;for each amount equal or exceeded
cmp #$10
bcc ChkWtr
iny
cmp #$19
bcc ChkWtr
iny
cmp #$1c
bcc ChkWtr ;note that for jumping, range is 0-4 for Y
iny
ChkWtr: lda #$01 ;set value here (apparently always set to 1)
sta DiffToHaltJump
lda SwimmingFlag ;if swimming flag disabled, branch
beq GetYPhy
ldy #$05 ;otherwise set Y to 5, range is 5-6
lda Whirlpool_Flag ;if whirlpool flag not set, branch
beq GetYPhy
iny ;otherwise increment to 6
GetYPhy: lda JumpMForceData,y ;store appropriate jump/swim
sta VerticalForce ;data here
lda FallMForceData,y
sta VerticalForceDown
lda InitMForceData,y
sta Player_Y_MoveForce
lda PlayerYSpdData,y
sta Player_Y_Speed
lda SwimmingFlag ;if swimming flag disabled, branch
beq PJumpSnd
lda #Sfx_EnemyStomp ;load swim/goomba stomp sound into
sta Square1SoundQueue ;square 1's sfx queue
lda Player_Y_Position
cmp #$14 ;check vertical low byte of player position
bcs X_Physics ;if below a certain point, branch
lda #$00 ;otherwise reset player's vertical speed
sta Player_Y_Speed ;and jump to something else to keep player
jmp X_Physics ;from swimming above water level
PJumpSnd: lda #Sfx_BigJump ;load big mario's jump sound by default
ldy PlayerSize ;is mario big?
beq SJumpSnd
lda #Sfx_SmallJump ;if not, load small mario's jump sound
SJumpSnd: sta Square1SoundQueue ;store appropriate jump sound in square 1 sfx queue
X_Physics: ldy #$00
sty $00 ;init value here
lda Player_State ;if mario is on the ground, branch
beq ProcPRun
lda Player_XSpeedAbsolute ;check something that seems to be related
cmp #$19 ;to mario's speed
bcs GetXPhy ;if =>$19 branch here
bcc ChkRFast ;if not branch elsewhere
ProcPRun: iny ;if mario on the ground, increment Y
lda AreaType ;check area type
beq ChkRFast ;if water type, branch
dey ;decrement Y by default for non-water type area
lda Left_Right_Buttons ;get left/right controller bits
cmp Player_MovingDir ;check against moving direction
bne ChkRFast ;if controller bits <> moving direction, skip this part
lda A_B_Buttons ;check for b button pressed
and #B_Button
bne SetRTmr ;if pressed, skip ahead to set timer
lda RunningTimer ;check for running timer set
bne GetXPhy ;if set, branch
ChkRFast: iny ;if running timer not set or level type is water,
inc $00 ;increment Y again and temp variable in memory
lda RunningSpeed
bne FastXSp ;if running speed set here, branch
lda Player_XSpeedAbsolute
cmp #$21 ;otherwise check player's walking/running speed
bcc GetXPhy ;if less than a certain amount, branch ahead
FastXSp: inc $00 ;if running speed set or speed => $21 increment $00
jmp GetXPhy ;and jump ahead
SetRTmr: lda #$0a ;if b button pressed, set running timer
sta RunningTimer
GetXPhy: lda MaxLeftXSpdData,y ;get maximum speed to the left
sta MaximumLeftSpeed
lda GameEngineSubroutine ;check for specific routine running
cmp #$07 ;(player entrance)
bne GetXPhy2 ;if not running, skip and use old value of Y
ldy #$03 ;otherwise set Y to 3
GetXPhy2: lda MaxRightXSpdData,y ;get maximum speed to the right
sta MaximumRightSpeed
ldy $00 ;get other value in memory
lda FrictionData,y ;get value using value in memory as offset
sta FrictionAdderLow
lda #$00
sta FrictionAdderHigh ;init something here
lda PlayerFacingDir
cmp Player_MovingDir ;check facing direction against moving direction
beq ExitPhy ;if the same, branch to leave
asl FrictionAdderLow ;otherwise shift d7 of friction adder low into carry
rol FrictionAdderHigh ;then rotate carry onto d0 of friction adder high
ExitPhy: rts ;and then leave
;-------------------------------------------------------------------------------------
PlayerAnimTmrData:
.db $02, $04, $07
GetPlayerAnimSpeed:
ldy #$00 ;initialize offset in Y
lda Player_XSpeedAbsolute ;check player's walking/running speed
cmp #$1c ;against preset amount
bcs SetRunSpd ;if greater than a certain amount, branch ahead
iny ;otherwise increment Y
cmp #$0e ;compare against lower amount
bcs ChkSkid ;if greater than this but not greater than first, skip increment
iny ;otherwise increment Y again
ChkSkid: lda SavedJoypadBits ;get controller bits
and #%01111111 ;mask out A button
beq SetAnimSpd ;if no other buttons pressed, branch ahead of all this
and #$03 ;mask out all others except left and right
cmp Player_MovingDir ;check against moving direction
bne ProcSkid ;if left/right controller bits <> moving direction, branch
lda #$00 ;otherwise set zero value here
SetRunSpd: sta RunningSpeed ;store zero or running speed here
jmp SetAnimSpd
ProcSkid: lda Player_XSpeedAbsolute ;check player's walking/running speed
cmp #$0b ;against one last amount
bcs SetAnimSpd ;if greater than this amount, branch
lda PlayerFacingDir
sta Player_MovingDir ;otherwise use facing direction to set moving direction
lda #$00
sta Player_X_Speed ;nullify player's horizontal speed
sta Player_X_MoveForce ;and dummy variable for player
SetAnimSpd: lda PlayerAnimTmrData,y ;get animation timer setting using Y as offset
sta PlayerAnimTimerSet
rts
;-------------------------------------------------------------------------------------
ImposeFriction:
and Player_CollisionBits ;perform AND between left/right controller bits and collision flag
cmp #$00 ;then compare to zero (this instruction is redundant)
bne JoypFrict ;if any bits set, branch to next part
lda Player_X_Speed
beq SetAbsSpd ;if player has no horizontal speed, branch ahead to last part
bpl RghtFrict ;if player moving to the right, branch to slow
bmi LeftFrict ;otherwise logic dictates player moving left, branch to slow
JoypFrict: lsr ;put right controller bit into carry
bcc RghtFrict ;if left button pressed, carry = 0, thus branch
LeftFrict: lda Player_X_MoveForce ;load value set here
clc
adc FrictionAdderLow ;add to it another value set here
sta Player_X_MoveForce ;store here
lda Player_X_Speed
adc FrictionAdderHigh ;add value plus carry to horizontal speed
sta Player_X_Speed ;set as new horizontal speed
cmp MaximumRightSpeed ;compare against maximum value for right movement
bmi XSpdSign ;if horizontal speed greater negatively, branch
lda MaximumRightSpeed ;otherwise set preset value as horizontal speed
sta Player_X_Speed ;thus slowing the player's left movement down
jmp SetAbsSpd ;skip to the end
RghtFrict: lda Player_X_MoveForce ;load value set here
sec
sbc FrictionAdderLow ;subtract from it another value set here
sta Player_X_MoveForce ;store here
lda Player_X_Speed
sbc FrictionAdderHigh ;subtract value plus borrow from horizontal speed
sta Player_X_Speed ;set as new horizontal speed
cmp MaximumLeftSpeed ;compare against maximum value for left movement
bpl XSpdSign ;if horizontal speed greater positively, branch
lda MaximumLeftSpeed ;otherwise set preset value as horizontal speed
sta Player_X_Speed ;thus slowing the player's right movement down
XSpdSign: cmp #$00 ;if player not moving or moving to the right,
bpl SetAbsSpd ;branch and leave horizontal speed value unmodified
eor #$ff
clc ;otherwise get two's compliment to get absolute
adc #$01 ;unsigned walking/running speed
SetAbsSpd: sta Player_XSpeedAbsolute ;store walking/running speed here and leave
rts
;-------------------------------------------------------------------------------------
;$00 - used to store downward movement force in FireballObjCore
;$02 - used to store maximum vertical speed in FireballObjCore
;$07 - used to store pseudorandom bit in BubbleCheck
ProcFireball_Bubble:
lda PlayerStatus ;check player's status
cmp #$02
bcc ProcAirBubbles ;if not fiery, branch
lda A_B_Buttons
and #B_Button ;check for b button pressed
beq ProcFireballs ;branch if not pressed
and PreviousA_B_Buttons
bne ProcFireballs ;if button pressed in previous frame, branch
lda FireballCounter ;load fireball counter
and #%00000001 ;get LSB and use as offset for buffer
tax
lda Fireball_State,x ;load fireball state
bne ProcFireballs ;if not inactive, branch
ldy Player_Y_HighPos ;if player too high or too low, branch
dey
bne ProcFireballs
lda CrouchingFlag ;if player crouching, branch
bne ProcFireballs
lda Player_State ;if player's state = climbing, branch
cmp #$03
beq ProcFireballs
lda #Sfx_Fireball ;play fireball sound effect
sta Square1SoundQueue
lda #$02 ;load state
sta Fireball_State,x
ldy PlayerAnimTimerSet ;copy animation frame timer setting
sty FireballThrowingTimer ;into fireball throwing timer
dey
sty PlayerAnimTimer ;decrement and store in player's animation timer
inc FireballCounter ;increment fireball counter
ProcFireballs:
ldx #$00
jsr FireballObjCore ;process first fireball object
ldx #$01
jsr FireballObjCore ;process second fireball object, then do air bubbles
ProcAirBubbles:
lda AreaType ;if not water type level, skip the rest of this
bne BublExit
ldx #$02 ;otherwise load counter and use as offset
BublLoop: stx ObjectOffset ;store offset
jsr BubbleCheck ;check timers and coordinates, create air bubble
jsr RelativeBubblePosition ;get relative coordinates
jsr GetBubbleOffscreenBits ;get offscreen information
jsr DrawBubble ;draw the air bubble
dex
bpl BublLoop ;do this until all three are handled
BublExit: rts ;then leave
FireballXSpdData:
.db $40, $c0
FireballObjCore:
stx ObjectOffset ;store offset as current object
lda Fireball_State,x ;check for d7 = 1
asl
bcs FireballExplosion ;if so, branch to get relative coordinates and draw explosion
ldy Fireball_State,x ;if fireball inactive, branch to leave
beq NoFBall
dey ;if fireball state set to 1, skip this part and just run it
beq RunFB
lda Player_X_Position ;get player's horizontal position
adc #$04 ;add four pixels and store as fireball's horizontal position
sta Fireball_X_Position,x
lda Player_PageLoc ;get player's page location
adc #$00 ;add carry and store as fireball's page location
sta Fireball_PageLoc,x
lda Player_Y_Position ;get player's vertical position and store
sta Fireball_Y_Position,x
lda #$01 ;set high byte of vertical position
sta Fireball_Y_HighPos,x
ldy PlayerFacingDir ;get player's facing direction
dey ;decrement to use as offset here
lda FireballXSpdData,y ;set horizontal speed of fireball accordingly
sta Fireball_X_Speed,x
lda #$04 ;set vertical speed of fireball
sta Fireball_Y_Speed,x
lda #$07
sta Fireball_BoundBoxCtrl,x ;set bounding box size control for fireball
dec Fireball_State,x ;decrement state to 1 to skip this part from now on
RunFB: txa ;add 7 to offset to use
clc ;as fireball offset for next routines
adc #$07
tax
lda #$50 ;set downward movement force here
sta $00
lda #$03 ;set maximum speed here
sta $02
lda #$00
jsr ImposeGravity ;do sub here to impose gravity on fireball and move vertically
jsr MoveObjectHorizontally ;do another sub to move it horizontally
ldx ObjectOffset ;return fireball offset to X
jsr RelativeFireballPosition ;get relative coordinates
jsr GetFireballOffscreenBits ;get offscreen information
jsr GetFireballBoundBox ;get bounding box coordinates
jsr FireballBGCollision ;do fireball to background collision detection
lda FBall_OffscreenBits ;get fireball offscreen bits
and #%11001100 ;mask out certain bits
bne EraseFB ;if any bits still set, branch to kill fireball
jsr FireballEnemyCollision ;do fireball to enemy collision detection and deal with collisions
jmp DrawFireball ;draw fireball appropriately and leave
EraseFB: lda #$00 ;erase fireball state
sta Fireball_State,x
NoFBall: rts ;leave
FireballExplosion:
jsr RelativeFireballPosition
jmp DrawExplosion_Fireball
BubbleCheck:
lda PseudoRandomBitReg+1,x ;get part of LSFR
and #$01
sta $07 ;store pseudorandom bit here
lda Bubble_Y_Position,x ;get vertical coordinate for air bubble
cmp #$f8 ;if offscreen coordinate not set,
bne MoveBubl ;branch to move air bubble
lda AirBubbleTimer ;if air bubble timer not expired,
bne ExitBubl ;branch to leave, otherwise create new air bubble
SetupBubble:
ldy #$00 ;load default value here
lda PlayerFacingDir ;get player's facing direction
lsr ;move d0 to carry
bcc PosBubl ;branch to use default value if facing left
ldy #$08 ;otherwise load alternate value here
PosBubl: tya ;use value loaded as adder
adc Player_X_Position ;add to player's horizontal position
sta Bubble_X_Position,x ;save as horizontal position for airbubble
lda Player_PageLoc
adc #$00 ;add carry to player's page location
sta Bubble_PageLoc,x ;save as page location for airbubble
lda Player_Y_Position
clc ;add eight pixels to player's vertical position
adc #$08
sta Bubble_Y_Position,x ;save as vertical position for air bubble
lda #$01
sta Bubble_Y_HighPos,x ;set vertical high byte for air bubble
ldy $07 ;get pseudorandom bit, use as offset
lda BubbleTimerData,y ;get data for air bubble timer
sta AirBubbleTimer ;set air bubble timer
MoveBubl: ldy $07 ;get pseudorandom bit again, use as offset
lda Bubble_YMF_Dummy,x
sec ;subtract pseudorandom amount from dummy variable
sbc Bubble_MForceData,y
sta Bubble_YMF_Dummy,x ;save dummy variable
lda Bubble_Y_Position,x
sbc #$00 ;subtract borrow from airbubble's vertical coordinate
cmp #$20 ;if below the status bar,
bcs Y_Bubl ;branch to go ahead and use to move air bubble upwards
lda #$f8 ;otherwise set offscreen coordinate
Y_Bubl: sta Bubble_Y_Position,x ;store as new vertical coordinate for air bubble
ExitBubl: rts ;leave
Bubble_MForceData:
.db $ff, $50
BubbleTimerData:
.db $40, $20
;-------------------------------------------------------------------------------------
RunGameTimer:
lda OperMode ;get primary mode of operation
beq ExGTimer ;branch to leave if in title screen mode
lda GameEngineSubroutine
cmp #$08 ;if routine number less than eight running,
bcc ExGTimer ;branch to leave
cmp #$0b ;if running death routine,
beq ExGTimer ;branch to leave
lda Player_Y_HighPos
cmp #$02 ;if player below the screen,
bcs ExGTimer ;branch to leave regardless of level type
lda GameTimerCtrlTimer ;if game timer control not yet expired,
bne ExGTimer ;branch to leave
lda GameTimerDisplay
ora GameTimerDisplay+1 ;otherwise check game timer digits
ora GameTimerDisplay+2
beq TimeUpOn ;if game timer digits at 000, branch to time-up code
ldy GameTimerDisplay ;otherwise check first digit
dey ;if first digit not on 1,
bne ResGTCtrl ;branch to reset game timer control
lda GameTimerDisplay+1 ;otherwise check second and third digits
ora GameTimerDisplay+2
bne ResGTCtrl ;if timer not at 100, branch to reset game timer control
lda #TimeRunningOutMusic
sta EventMusicQueue ;otherwise load time running out music
ResGTCtrl: lda #$18 ;reset game timer control
sta GameTimerCtrlTimer
ldy #$23 ;set offset for last digit
lda #$ff ;set value to decrement game timer digit
sta DigitModifier+5
jsr DigitsMathRoutine ;do sub to decrement game timer slowly
lda #$a4 ;set status nybbles to update game timer display
jmp PrintStatusBarNumbers ;do sub to update the display
TimeUpOn: sta PlayerStatus ;init player status (note A will always be zero here)
jsr ForceInjury ;do sub to kill the player (note player is small here)
inc GameTimerExpiredFlag ;set game timer expiration flag
ExGTimer: rts ;leave
;-------------------------------------------------------------------------------------
WarpZoneObject:
lda ScrollLock ;check for scroll lock flag
beq ExGTimer ;branch if not set to leave
lda Player_Y_Position ;check to see if player's vertical coordinate has
and Player_Y_HighPos ;same bits set as in vertical high byte (why?)
bne ExGTimer ;if so, branch to leave
sta ScrollLock ;otherwise nullify scroll lock flag
inc WarpZoneControl ;increment warp zone flag to make warp pipes for warp zone
jmp EraseEnemyObject ;kill this object
;-------------------------------------------------------------------------------------
;$00 - used in WhirlpoolActivate to store whirlpool length / 2, page location of center of whirlpool
;and also to store movement force exerted on player
;$01 - used in ProcessWhirlpools to store page location of right extent of whirlpool
;and in WhirlpoolActivate to store center of whirlpool
;$02 - used in ProcessWhirlpools to store right extent of whirlpool and in
;WhirlpoolActivate to store maximum vertical speed
ProcessWhirlpools:
lda AreaType ;check for water type level
bne ExitWh ;branch to leave if not found
sta Whirlpool_Flag ;otherwise initialize whirlpool flag
lda TimerControl ;if master timer control set,
bne ExitWh ;branch to leave
ldy #$04 ;otherwise start with last whirlpool data
WhLoop: lda Whirlpool_LeftExtent,y ;get left extent of whirlpool
clc
adc Whirlpool_Length,y ;add length of whirlpool
sta $02 ;store result as right extent here
lda Whirlpool_PageLoc,y ;get page location
beq NextWh ;if none or page 0, branch to get next data
adc #$00 ;add carry
sta $01 ;store result as page location of right extent here
lda Player_X_Position ;get player's horizontal position
sec
sbc Whirlpool_LeftExtent,y ;subtract left extent
lda Player_PageLoc ;get player's page location
sbc Whirlpool_PageLoc,y ;subtract borrow
bmi NextWh ;if player too far left, branch to get next data
lda $02 ;otherwise get right extent
sec
sbc Player_X_Position ;subtract player's horizontal coordinate
lda $01 ;get right extent's page location
sbc Player_PageLoc ;subtract borrow
bpl WhirlpoolActivate ;if player within right extent, branch to whirlpool code
NextWh: dey ;move onto next whirlpool data
bpl WhLoop ;do this until all whirlpools are checked
ExitWh: rts ;leave
WhirlpoolActivate:
lda Whirlpool_Length,y ;get length of whirlpool
lsr ;divide by 2
sta $00 ;save here
lda Whirlpool_LeftExtent,y ;get left extent of whirlpool
clc
adc $00 ;add length divided by 2
sta $01 ;save as center of whirlpool
lda Whirlpool_PageLoc,y ;get page location
adc #$00 ;add carry
sta $00 ;save as page location of whirlpool center
lda FrameCounter ;get frame counter
lsr ;shift d0 into carry (to run on every other frame)
bcc WhPull ;if d0 not set, branch to last part of code
lda $01 ;get center
sec
sbc Player_X_Position ;subtract player's horizontal coordinate
lda $00 ;get page location of center
sbc Player_PageLoc ;subtract borrow
bpl LeftWh ;if player to the left of center, branch
lda Player_X_Position ;otherwise slowly pull player left, towards the center
sec
sbc #$01 ;subtract one pixel
sta Player_X_Position ;set player's new horizontal coordinate
lda Player_PageLoc
sbc #$00 ;subtract borrow
jmp SetPWh ;jump to set player's new page location
LeftWh: lda Player_CollisionBits ;get player's collision bits
lsr ;shift d0 into carry
bcc WhPull ;if d0 not set, branch
lda Player_X_Position ;otherwise slowly pull player right, towards the center
clc
adc #$01 ;add one pixel
sta Player_X_Position ;set player's new horizontal coordinate
lda Player_PageLoc
adc #$00 ;add carry
SetPWh: sta Player_PageLoc ;set player's new page location
WhPull: lda #$10
sta $00 ;set vertical movement force
lda #$01
sta Whirlpool_Flag ;set whirlpool flag to be used later
sta $02 ;also set maximum vertical speed
lsr
tax ;set X for player offset
jmp ImposeGravity ;jump to put whirlpool effect on player vertically, do not return
;-------------------------------------------------------------------------------------
FlagpoleScoreMods:
.db $05, $02, $08, $04, $01
FlagpoleScoreDigits:
.db $03, $03, $04, $04, $04
FlagpoleRoutine:
ldx #$05 ;set enemy object offset
stx ObjectOffset ;to special use slot
lda Enemy_ID,x
cmp #FlagpoleFlagObject ;if flagpole flag not found,
bne ExitFlagP ;branch to leave
lda GameEngineSubroutine
cmp #$04 ;if flagpole slide routine not running,
bne SkipScore ;branch to near the end of code
lda Player_State
cmp #$03 ;if player state not climbing,
bne SkipScore ;branch to near the end of code
lda Enemy_Y_Position,x ;check flagpole flag's vertical coordinate
cmp #$aa ;if flagpole flag down to a certain point,
bcs GiveFPScr ;branch to end the level
lda Player_Y_Position ;check player's vertical coordinate
cmp #$a2 ;if player down to a certain point,
bcs GiveFPScr ;branch to end the level
lda Enemy_YMF_Dummy,x
adc #$ff ;add movement amount to dummy variable
sta Enemy_YMF_Dummy,x ;save dummy variable
lda Enemy_Y_Position,x ;get flag's vertical coordinate
adc #$01 ;add 1 plus carry to move flag, and
sta Enemy_Y_Position,x ;store vertical coordinate
lda FlagpoleFNum_YMFDummy
sec ;subtract movement amount from dummy variable
sbc #$ff
sta FlagpoleFNum_YMFDummy ;save dummy variable
lda FlagpoleFNum_Y_Pos
sbc #$01 ;subtract one plus borrow to move floatey number,
sta FlagpoleFNum_Y_Pos ;and store vertical coordinate here
SkipScore: jmp FPGfx ;jump to skip ahead and draw flag and floatey number
GiveFPScr: ldy FlagpoleScore ;get score offset from earlier (when player touched flagpole)
lda FlagpoleScoreMods,y ;get amount to award player points
ldx FlagpoleScoreDigits,y ;get digit with which to award points
sta DigitModifier,x ;store in digit modifier
jsr AddToScore ;do sub to award player points depending on height of collision
lda #$05
sta GameEngineSubroutine ;set to run end-of-level subroutine on next frame
FPGfx: jsr GetEnemyOffscreenBits ;get offscreen information
jsr RelativeEnemyPosition ;get relative coordinates
jsr FlagpoleGfxHandler ;draw flagpole flag and floatey number
ExitFlagP: rts
;-------------------------------------------------------------------------------------
Jumpspring_Y_PosData:
.db $08, $10, $08, $00
JumpspringHandler:
jsr GetEnemyOffscreenBits ;get offscreen information
lda TimerControl ;check master timer control
bne DrawJSpr ;branch to last section if set
lda JumpspringAnimCtrl ;check jumpspring frame control
beq DrawJSpr ;branch to last section if not set
tay
dey ;subtract one from frame control,
tya ;the only way a poor nmos 6502 can
and #%00000010 ;mask out all but d1, original value still in Y
bne DownJSpr ;if set, branch to move player up
inc Player_Y_Position
inc Player_Y_Position ;move player's vertical position down two pixels
jmp PosJSpr ;skip to next part
DownJSpr: dec Player_Y_Position ;move player's vertical position up two pixels
dec Player_Y_Position
PosJSpr: lda Jumpspring_FixedYPos,x ;get permanent vertical position
clc
adc Jumpspring_Y_PosData,y ;add value using frame control as offset
sta Enemy_Y_Position,x ;store as new vertical position
cpy #$01 ;check frame control offset (second frame is $00)
bcc BounceJS ;if offset not yet at third frame ($01), skip to next part
lda A_B_Buttons
and #A_Button ;check saved controller bits for A button press
beq BounceJS ;skip to next part if A not pressed
and PreviousA_B_Buttons ;check for A button pressed in previous frame
bne BounceJS ;skip to next part if so
lda #$f4
sta JumpspringForce ;otherwise write new jumpspring force here
BounceJS: cpy #$03 ;check frame control offset again
bne DrawJSpr ;skip to last part if not yet at fifth frame ($03)
lda JumpspringForce
sta Player_Y_Speed ;store jumpspring force as player's new vertical speed
lda #$00
sta JumpspringAnimCtrl ;initialize jumpspring frame control
DrawJSpr: jsr RelativeEnemyPosition ;get jumpspring's relative coordinates
jsr EnemyGfxHandler ;draw jumpspring
jsr OffscreenBoundsCheck ;check to see if we need to kill it
lda JumpspringAnimCtrl ;if frame control at zero, don't bother
beq ExJSpring ;trying to animate it, just leave
lda JumpspringTimer
bne ExJSpring ;if jumpspring timer not expired yet, leave
lda #$04
sta JumpspringTimer ;otherwise initialize jumpspring timer
inc JumpspringAnimCtrl ;increment frame control to animate jumpspring
ExJSpring: rts ;leave
;-------------------------------------------------------------------------------------
Setup_Vine:
lda #VineObject ;load identifier for vine object
sta Enemy_ID,x ;store in buffer
lda #$01
sta Enemy_Flag,x ;set flag for enemy object buffer
lda Block_PageLoc,y
sta Enemy_PageLoc,x ;copy page location from previous object
lda Block_X_Position,y
sta Enemy_X_Position,x ;copy horizontal coordinate from previous object
lda Block_Y_Position,y
sta Enemy_Y_Position,x ;copy vertical coordinate from previous object
ldy VineFlagOffset ;load vine flag/offset to next available vine slot
bne NextVO ;if set at all, don't bother to store vertical
sta VineStart_Y_Position ;otherwise store vertical coordinate here
NextVO: txa ;store object offset to next available vine slot
sta VineObjOffset,y ;using vine flag as offset
inc VineFlagOffset ;increment vine flag offset
lda #Sfx_GrowVine
sta Square2SoundQueue ;load vine grow sound
rts
;-------------------------------------------------------------------------------------
;$06-$07 - used as address to block buffer data
;$02 - used as vertical high nybble of block buffer offset
VineHeightData:
.db $30, $60
VineObjectHandler:
cpx #$05 ;check enemy offset for special use slot
bne ExitVH ;if not in last slot, branch to leave
ldy VineFlagOffset
dey ;decrement vine flag in Y, use as offset
lda VineHeight
cmp VineHeightData,y ;if vine has reached certain height,
beq RunVSubs ;branch ahead to skip this part
lda FrameCounter ;get frame counter
lsr ;shift d1 into carry
lsr
bcc RunVSubs ;if d1 not set (2 frames every 4) skip this part
lda Enemy_Y_Position+5
sbc #$01 ;subtract vertical position of vine
sta Enemy_Y_Position+5 ;one pixel every frame it's time
inc VineHeight ;increment vine height
RunVSubs: lda VineHeight ;if vine still very small,
cmp #$08 ;branch to leave
bcc ExitVH
jsr RelativeEnemyPosition ;get relative coordinates of vine,
jsr GetEnemyOffscreenBits ;and any offscreen bits
ldy #$00 ;initialize offset used in draw vine sub
VDrawLoop: jsr DrawVine ;draw vine
iny ;increment offset
cpy VineFlagOffset ;if offset in Y and offset here
bne VDrawLoop ;do not yet match, loop back to draw more vine
lda Enemy_OffscreenBits
and #%00001100 ;mask offscreen bits
beq WrCMTile ;if none of the saved offscreen bits set, skip ahead
dey ;otherwise decrement Y to get proper offset again
KillVine: ldx VineObjOffset,y ;get enemy object offset for this vine object
jsr EraseEnemyObject ;kill this vine object
dey ;decrement Y
bpl KillVine ;if any vine objects left, loop back to kill it
sta VineFlagOffset ;initialize vine flag/offset
sta VineHeight ;initialize vine height
WrCMTile: lda VineHeight ;check vine height
cmp #$20 ;if vine small (less than 32 pixels tall)
bcc ExitVH ;then branch ahead to leave
ldx #$06 ;set offset in X to last enemy slot
lda #$01 ;set A to obtain horizontal in $04, but we don't care
ldy #$1b ;set Y to offset to get block at ($04, $10) of coordinates
jsr BlockBufferCollision ;do a sub to get block buffer address set, return contents
ldy $02
cpy #$d0 ;if vertical high nybble offset beyond extent of
bcs ExitVH ;current block buffer, branch to leave, do not write
lda ($06),y ;otherwise check contents of block buffer at
bne ExitVH ;current offset, if not empty, branch to leave
lda #$26
sta ($06),y ;otherwise, write climbing metatile to block buffer
ExitVH: ldx ObjectOffset ;get enemy object offset and leave
rts
;-------------------------------------------------------------------------------------
CannonBitmasks:
.db %00001111, %00000111
ProcessCannons:
lda AreaType ;get area type
beq ExCannon ;if water type area, branch to leave
ldx #$02
ThreeSChk: stx ObjectOffset ;start at third enemy slot
lda Enemy_Flag,x ;check enemy buffer flag
bne Chk_BB ;if set, branch to check enemy
lda PseudoRandomBitReg+1,x ;otherwise get part of LSFR
ldy SecondaryHardMode ;get secondary hard mode flag, use as offset
and CannonBitmasks,y ;mask out bits of LSFR as decided by flag
cmp #$06 ;check to see if lower nybble is above certain value
bcs Chk_BB ;if so, branch to check enemy
tay ;transfer masked contents of LSFR to Y as pseudorandom offset
lda Cannon_PageLoc,y ;get page location
beq Chk_BB ;if not set or on page 0, branch to check enemy
lda Cannon_Timer,y ;get cannon timer
beq FireCannon ;if expired, branch to fire cannon
sbc #$00 ;otherwise subtract borrow (note carry will always be clear here)
sta Cannon_Timer,y ;to count timer down
jmp Chk_BB ;then jump ahead to check enemy
FireCannon:
lda TimerControl ;if master timer control set,
bne Chk_BB ;branch to check enemy
lda #$0e ;otherwise we start creating one
sta Cannon_Timer,y ;first, reset cannon timer
lda Cannon_PageLoc,y ;get page location of cannon
sta Enemy_PageLoc,x ;save as page location of bullet bill
lda Cannon_X_Position,y ;get horizontal coordinate of cannon
sta Enemy_X_Position,x ;save as horizontal coordinate of bullet bill
lda Cannon_Y_Position,y ;get vertical coordinate of cannon
sec
sbc #$08 ;subtract eight pixels (because enemies are 24 pixels tall)
sta Enemy_Y_Position,x ;save as vertical coordinate of bullet bill
lda #$01
sta Enemy_Y_HighPos,x ;set vertical high byte of bullet bill
sta Enemy_Flag,x ;set buffer flag
lsr ;shift right once to init A
sta Enemy_State,x ;then initialize enemy's state
lda #$09
sta Enemy_BoundBoxCtrl,x ;set bounding box size control for bullet bill
lda #BulletBill_CannonVar
sta Enemy_ID,x ;load identifier for bullet bill (cannon variant)
jmp Next3Slt ;move onto next slot
Chk_BB: lda Enemy_ID,x ;check enemy identifier for bullet bill (cannon variant)
cmp #BulletBill_CannonVar
bne Next3Slt ;if not found, branch to get next slot
jsr OffscreenBoundsCheck ;otherwise, check to see if it went offscreen
lda Enemy_Flag,x ;check enemy buffer flag
beq Next3Slt ;if not set, branch to get next slot
jsr GetEnemyOffscreenBits ;otherwise, get offscreen information
jsr BulletBillHandler ;then do sub to handle bullet bill
Next3Slt: dex ;move onto next slot
bpl ThreeSChk ;do this until first three slots are checked
ExCannon: rts ;then leave
;--------------------------------
BulletBillXSpdData:
.db $18, $e8
BulletBillHandler:
lda TimerControl ;if master timer control set,
bne RunBBSubs ;branch to run subroutines except movement sub
lda Enemy_State,x
bne ChkDSte ;if bullet bill's state set, branch to check defeated state
lda Enemy_OffscreenBits ;otherwise load offscreen bits
and #%00001100 ;mask out bits
cmp #%00001100 ;check to see if all bits are set
beq KillBB ;if so, branch to kill this object
ldy #$01 ;set to move right by default
jsr PlayerEnemyDiff ;get horizontal difference between player and bullet bill
bmi SetupBB ;if enemy to the left of player, branch
iny ;otherwise increment to move left
SetupBB: sty Enemy_MovingDir,x ;set bullet bill's moving direction
dey ;decrement to use as offset
lda BulletBillXSpdData,y ;get horizontal speed based on moving direction
sta Enemy_X_Speed,x ;and store it
lda $00 ;get horizontal difference
adc #$28 ;add 40 pixels
cmp #$50 ;if less than a certain amount, player is too close
bcc KillBB ;to cannon either on left or right side, thus branch
lda #$01
sta Enemy_State,x ;otherwise set bullet bill's state
lda #$0a
sta EnemyFrameTimer,x ;set enemy frame timer
lda #Sfx_Blast
sta Square2SoundQueue ;play fireworks/gunfire sound
ChkDSte: lda Enemy_State,x ;check enemy state for d5 set
and #%00100000
beq BBFly ;if not set, skip to move horizontally
jsr MoveD_EnemyVertically ;otherwise do sub to move bullet bill vertically
BBFly: jsr MoveEnemyHorizontally ;do sub to move bullet bill horizontally
RunBBSubs: jsr GetEnemyOffscreenBits ;get offscreen information
jsr RelativeEnemyPosition ;get relative coordinates
jsr GetEnemyBoundBox ;get bounding box coordinates
jsr PlayerEnemyCollision ;handle player to enemy collisions
jmp EnemyGfxHandler ;draw the bullet bill and leave
KillBB: jsr EraseEnemyObject ;kill bullet bill and leave
rts
;-------------------------------------------------------------------------------------
HammerEnemyOfsData:
.db $04, $04, $04, $05, $05, $05
.db $06, $06, $06
HammerXSpdData:
.db $10, $f0
SpawnHammerObj:
lda PseudoRandomBitReg+1 ;get pseudorandom bits from
and #%00000111 ;second part of LSFR
bne SetMOfs ;if any bits are set, branch and use as offset
lda PseudoRandomBitReg+1
and #%00001000 ;get d3 from same part of LSFR
SetMOfs: tay ;use either d3 or d2-d0 for offset here
lda Misc_State,y ;if any values loaded in
bne NoHammer ;$2a-$32 where offset is then leave with carry clear
ldx HammerEnemyOfsData,y ;get offset of enemy slot to check using Y as offset
lda Enemy_Flag,x ;check enemy buffer flag at offset
bne NoHammer ;if buffer flag set, branch to leave with carry clear
ldx ObjectOffset ;get original enemy object offset
txa
sta HammerEnemyOffset,y ;save here
lda #$90
sta Misc_State,y ;save hammer's state here
lda #$07
sta Misc_BoundBoxCtrl,y ;set something else entirely, here
sec ;return with carry set
rts
NoHammer: ldx ObjectOffset ;get original enemy object offset
clc ;return with carry clear
rts
;--------------------------------
;$00 - used to set downward force
;$01 - used to set upward force (residual)
;$02 - used to set maximum speed
ProcHammerObj:
lda TimerControl ;if master timer control set
bne RunHSubs ;skip all of this code and go to last subs at the end
lda Misc_State,x ;otherwise get hammer's state
and #%01111111 ;mask out d7
ldy HammerEnemyOffset,x ;get enemy object offset that spawned this hammer
cmp #$02 ;check hammer's state
beq SetHSpd ;if currently at 2, branch
bcs SetHPos ;if greater than 2, branch elsewhere
txa
clc ;add 13 bytes to use
adc #$0d ;proper misc object
tax ;return offset to X
lda #$10
sta $00 ;set downward movement force
lda #$0f
sta $01 ;set upward movement force (not used)
lda #$04
sta $02 ;set maximum vertical speed
lda #$00 ;set A to impose gravity on hammer
jsr ImposeGravity ;do sub to impose gravity on hammer and move vertically
jsr MoveObjectHorizontally ;do sub to move it horizontally
ldx ObjectOffset ;get original misc object offset
jmp RunAllH ;branch to essential subroutines
SetHSpd: lda #$fe
sta Misc_Y_Speed,x ;set hammer's vertical speed
lda Enemy_State,y ;get enemy object state
and #%11110111 ;mask out d3
sta Enemy_State,y ;store new state
ldx Enemy_MovingDir,y ;get enemy's moving direction
dex ;decrement to use as offset
lda HammerXSpdData,x ;get proper speed to use based on moving direction
ldx ObjectOffset ;reobtain hammer's buffer offset
sta Misc_X_Speed,x ;set hammer's horizontal speed
SetHPos: dec Misc_State,x ;decrement hammer's state
lda Enemy_X_Position,y ;get enemy's horizontal position
clc
adc #$02 ;set position 2 pixels to the right
sta Misc_X_Position,x ;store as hammer's horizontal position
lda Enemy_PageLoc,y ;get enemy's page location
adc #$00 ;add carry
sta Misc_PageLoc,x ;store as hammer's page location
lda Enemy_Y_Position,y ;get enemy's vertical position
sec
sbc #$0a ;move position 10 pixels upward
sta Misc_Y_Position,x ;store as hammer's vertical position
lda #$01
sta Misc_Y_HighPos,x ;set hammer's vertical high byte
bne RunHSubs ;unconditional branch to skip first routine
RunAllH: jsr PlayerHammerCollision ;handle collisions
RunHSubs: jsr GetMiscOffscreenBits ;get offscreen information
jsr RelativeMiscPosition ;get relative coordinates
jsr GetMiscBoundBox ;get bounding box coordinates
jsr DrawHammer ;draw the hammer
rts ;and we are done here
;-------------------------------------------------------------------------------------
;$02 - used to store vertical high nybble offset from block buffer routine
;$06 - used to store low byte of block buffer address
CoinBlock:
jsr FindEmptyMiscSlot ;set offset for empty or last misc object buffer slot
lda Block_PageLoc,x ;get page location of block object
sta Misc_PageLoc,y ;store as page location of misc object
lda Block_X_Position,x ;get horizontal coordinate of block object
ora #$05 ;add 5 pixels
sta Misc_X_Position,y ;store as horizontal coordinate of misc object
lda Block_Y_Position,x ;get vertical coordinate of block object
sbc #$10 ;subtract 16 pixels
sta Misc_Y_Position,y ;store as vertical coordinate of misc object
jmp JCoinC ;jump to rest of code as applies to this misc object
SetupJumpCoin:
jsr FindEmptyMiscSlot ;set offset for empty or last misc object buffer slot
lda Block_PageLoc2,x ;get page location saved earlier
sta Misc_PageLoc,y ;and save as page location for misc object
lda $06 ;get low byte of block buffer offset
asl
asl ;multiply by 16 to use lower nybble
asl
asl
ora #$05 ;add five pixels
sta Misc_X_Position,y ;save as horizontal coordinate for misc object
lda $02 ;get vertical high nybble offset from earlier
adc #$20 ;add 32 pixels for the status bar
sta Misc_Y_Position,y ;store as vertical coordinate
JCoinC: lda #$fb
sta Misc_Y_Speed,y ;set vertical speed
lda #$01
sta Misc_Y_HighPos,y ;set vertical high byte
sta Misc_State,y ;set state for misc object
sta Square2SoundQueue ;load coin grab sound
stx ObjectOffset ;store current control bit as misc object offset
jsr GiveOneCoin ;update coin tally on the screen and coin amount variable
inc CoinTallyFor1Ups ;increment coin tally used to activate 1-up block flag
rts
FindEmptyMiscSlot:
ldy #$08 ;start at end of misc objects buffer
FMiscLoop: lda Misc_State,y ;get misc object state
beq UseMiscS ;branch if none found to use current offset
dey ;decrement offset
cpy #$05 ;do this for three slots
bne FMiscLoop ;do this until all slots are checked
ldy #$08 ;if no empty slots found, use last slot
UseMiscS: sty JumpCoinMiscOffset ;store offset of misc object buffer here (residual)
rts
;-------------------------------------------------------------------------------------
MiscObjectsCore:
ldx #$08 ;set at end of misc object buffer
MiscLoop: stx ObjectOffset ;store misc object offset here
lda Misc_State,x ;check misc object state
beq MiscLoopBack ;branch to check next slot
asl ;otherwise shift d7 into carry
bcc ProcJumpCoin ;if d7 not set, jumping coin, thus skip to rest of code here
jsr ProcHammerObj ;otherwise go to process hammer,
jmp MiscLoopBack ;then check next slot
;--------------------------------
;$00 - used to set downward force
;$01 - used to set upward force (residual)
;$02 - used to set maximum speed
ProcJumpCoin:
ldy Misc_State,x ;check misc object state
dey ;decrement to see if it's set to 1
beq JCoinRun ;if so, branch to handle jumping coin
inc Misc_State,x ;otherwise increment state to either start off or as timer
lda Misc_X_Position,x ;get horizontal coordinate for misc object
clc ;whether its jumping coin (state 0 only) or floatey number
adc ScrollAmount ;add current scroll speed
sta Misc_X_Position,x ;store as new horizontal coordinate
lda Misc_PageLoc,x ;get page location
adc #$00 ;add carry
sta Misc_PageLoc,x ;store as new page location
lda Misc_State,x
cmp #$30 ;check state of object for preset value
bne RunJCSubs ;if not yet reached, branch to subroutines
lda #$00
sta Misc_State,x ;otherwise nullify object state
jmp MiscLoopBack ;and move onto next slot
JCoinRun: txa
clc ;add 13 bytes to offset for next subroutine
adc #$0d
tax
lda #$50 ;set downward movement amount
sta $00
lda #$06 ;set maximum vertical speed
sta $02
lsr ;divide by 2 and set
sta $01 ;as upward movement amount (apparently residual)
lda #$00 ;set A to impose gravity on jumping coin
jsr ImposeGravity ;do sub to move coin vertically and impose gravity on it
ldx ObjectOffset ;get original misc object offset
lda Misc_Y_Speed,x ;check vertical speed
cmp #$05
bne RunJCSubs ;if not moving downward fast enough, keep state as-is
inc Misc_State,x ;otherwise increment state to change to floatey number
RunJCSubs: jsr RelativeMiscPosition ;get relative coordinates
jsr GetMiscOffscreenBits ;get offscreen information
jsr GetMiscBoundBox ;get bounding box coordinates (why?)
jsr JCoinGfxHandler ;draw the coin or floatey number
MiscLoopBack:
dex ;decrement misc object offset
bpl MiscLoop ;loop back until all misc objects handled
rts ;then leave
;-------------------------------------------------------------------------------------
CoinTallyOffsets:
.db $17, $1d
ScoreOffsets:
.db $0b, $11
StatusBarNybbles:
.db $02, $13
GiveOneCoin:
lda #$01 ;set digit modifier to add 1 coin
sta DigitModifier+5 ;to the current player's coin tally
ldx CurrentPlayer ;get current player on the screen
ldy CoinTallyOffsets,x ;get offset for player's coin tally
jsr DigitsMathRoutine ;update the coin tally
inc CoinTally ;increment onscreen player's coin amount
lda CoinTally
cmp #100 ;does player have 100 coins yet?
bne CoinPoints ;if not, skip all of this
lda #$00
sta CoinTally ;otherwise, reinitialize coin amount
inc NumberofLives ;give the player an extra life
lda #Sfx_ExtraLife
sta Square2SoundQueue ;play 1-up sound
CoinPoints:
lda #$02 ;set digit modifier to award
sta DigitModifier+4 ;200 points to the player
AddToScore:
ldx CurrentPlayer ;get current player
ldy ScoreOffsets,x ;get offset for player's score
jsr DigitsMathRoutine ;update the score internally with value in digit modifier
GetSBNybbles:
ldy CurrentPlayer ;get current player
lda StatusBarNybbles,y ;get nybbles based on player, use to update score and coins
UpdateNumber:
jsr PrintStatusBarNumbers ;print status bar numbers based on nybbles, whatever they be
ldy VRAM_Buffer1_Offset
lda VRAM_Buffer1-6,y ;check highest digit of score
bne NoZSup ;if zero, overwrite with space tile for zero suppression
lda #$24
sta VRAM_Buffer1-6,y
NoZSup: ldx ObjectOffset ;get enemy object buffer offset
rts
;-------------------------------------------------------------------------------------
SetupPowerUp:
lda #PowerUpObject ;load power-up identifier into
sta Enemy_ID+5 ;special use slot of enemy object buffer
lda Block_PageLoc,x ;store page location of block object
sta Enemy_PageLoc+5 ;as page location of power-up object
lda Block_X_Position,x ;store horizontal coordinate of block object
sta Enemy_X_Position+5 ;as horizontal coordinate of power-up object
lda #$01
sta Enemy_Y_HighPos+5 ;set vertical high byte of power-up object
lda Block_Y_Position,x ;get vertical coordinate of block object
sec
sbc #$08 ;subtract 8 pixels
sta Enemy_Y_Position+5 ;and use as vertical coordinate of power-up object
PwrUpJmp: lda #$01 ;this is a residual jump point in enemy object jump table
sta Enemy_State+5 ;set power-up object's state
sta Enemy_Flag+5 ;set buffer flag
lda #$03
sta Enemy_BoundBoxCtrl+5 ;set bounding box size control for power-up object
lda PowerUpType
cmp #$02 ;check currently loaded power-up type
bcs PutBehind ;if star or 1-up, branch ahead
lda PlayerStatus ;otherwise check player's current status
cmp #$02
bcc StrType ;if player not fiery, use status as power-up type
lsr ;otherwise shift right to force fire flower type
StrType: sta PowerUpType ;store type here
PutBehind: lda #%00100000
sta Enemy_SprAttrib+5 ;set background priority bit
lda #Sfx_GrowPowerUp
sta Square2SoundQueue ;load power-up reveal sound and leave
rts
;-------------------------------------------------------------------------------------
PowerUpObjHandler:
ldx #$05 ;set object offset for last slot in enemy object buffer
stx ObjectOffset
lda Enemy_State+5 ;check power-up object's state
beq ExitPUp ;if not set, branch to leave
asl ;shift to check if d7 was set in object state
bcc GrowThePowerUp ;if not set, branch ahead to skip this part
lda TimerControl ;if master timer control set,
bne RunPUSubs ;branch ahead to enemy object routines
lda PowerUpType ;check power-up type
beq ShroomM ;if normal mushroom, branch ahead to move it
cmp #$03
beq ShroomM ;if 1-up mushroom, branch ahead to move it
cmp #$02
bne RunPUSubs ;if not star, branch elsewhere to skip movement
jsr MoveJumpingEnemy ;otherwise impose gravity on star power-up and make it jump
jsr EnemyJump ;note that green paratroopa shares the same code here
jmp RunPUSubs ;then jump to other power-up subroutines
ShroomM: jsr MoveNormalEnemy ;do sub to make mushrooms move
jsr EnemyToBGCollisionDet ;deal with collisions
jmp RunPUSubs ;run the other subroutines
GrowThePowerUp:
lda FrameCounter ;get frame counter
and #$03 ;mask out all but 2 LSB
bne ChkPUSte ;if any bits set here, branch
dec Enemy_Y_Position+5 ;otherwise decrement vertical coordinate slowly
lda Enemy_State+5 ;load power-up object state
inc Enemy_State+5 ;increment state for next frame (to make power-up rise)
cmp #$11 ;if power-up object state not yet past 16th pixel,
bcc ChkPUSte ;branch ahead to last part here
lda #$10
sta Enemy_X_Speed,x ;otherwise set horizontal speed
lda #%10000000
sta Enemy_State+5 ;and then set d7 in power-up object's state
asl ;shift once to init A
sta Enemy_SprAttrib+5 ;initialize background priority bit set here
rol ;rotate A to set right moving direction
sta Enemy_MovingDir,x ;set moving direction
ChkPUSte: lda Enemy_State+5 ;check power-up object's state
cmp #$06 ;for if power-up has risen enough
bcc ExitPUp ;if not, don't even bother running these routines
RunPUSubs: jsr RelativeEnemyPosition ;get coordinates relative to screen
jsr GetEnemyOffscreenBits ;get offscreen bits
jsr GetEnemyBoundBox ;get bounding box coordinates
jsr DrawPowerUp ;draw the power-up object
jsr PlayerEnemyCollision ;check for collision with player
jsr OffscreenBoundsCheck ;check to see if it went offscreen
ExitPUp: rts ;and we're done
;-------------------------------------------------------------------------------------
;These apply to all routines in this section unless otherwise noted:
;$00 - used to store metatile from block buffer routine
;$02 - used to store vertical high nybble offset from block buffer routine
;$05 - used to store metatile stored in A at beginning of PlayerHeadCollision
;$06-$07 - used as block buffer address indirect
BlockYPosAdderData:
.db $04, $12
PlayerHeadCollision:
pha ;store metatile number to stack
lda #$11 ;load unbreakable block object state by default
ldx SprDataOffset_Ctrl ;load offset control bit here
ldy PlayerSize ;check player's size
bne DBlockSte ;if small, branch
lda #$12 ;otherwise load breakable block object state
DBlockSte: sta Block_State,x ;store into block object buffer
jsr DestroyBlockMetatile ;store blank metatile in vram buffer to write to name table
ldx SprDataOffset_Ctrl ;load offset control bit
lda $02 ;get vertical high nybble offset used in block buffer routine
sta Block_Orig_YPos,x ;set as vertical coordinate for block object
tay
lda $06 ;get low byte of block buffer address used in same routine
sta Block_BBuf_Low,x ;save as offset here to be used later
lda ($06),y ;get contents of block buffer at old address at $06, $07
jsr BlockBumpedChk ;do a sub to check which block player bumped head on
sta $00 ;store metatile here
ldy PlayerSize ;check player's size
bne ChkBrick ;if small, use metatile itself as contents of A
tya ;otherwise init A (note: big = 0)
ChkBrick: bcc PutMTileB ;if no match was found in previous sub, skip ahead
ldy #$11 ;otherwise load unbreakable state into block object buffer
sty Block_State,x ;note this applies to both player sizes
lda #$c4 ;load empty block metatile into A for now
ldy $00 ;get metatile from before
cpy #$58 ;is it brick with coins (with line)?
beq StartBTmr ;if so, branch
cpy #$5d ;is it brick with coins (without line)?
bne PutMTileB ;if not, branch ahead to store empty block metatile
StartBTmr: lda BrickCoinTimerFlag ;check brick coin timer flag
bne ContBTmr ;if set, timer expired or counting down, thus branch
lda #$0b
sta BrickCoinTimer ;if not set, set brick coin timer
inc BrickCoinTimerFlag ;and set flag linked to it
ContBTmr: lda BrickCoinTimer ;check brick coin timer
bne PutOldMT ;if not yet expired, branch to use current metatile
ldy #$c4 ;otherwise use empty block metatile
PutOldMT: tya ;put metatile into A
PutMTileB: sta Block_Metatile,x ;store whatever metatile be appropriate here
jsr InitBlock_XY_Pos ;get block object horizontal coordinates saved
ldy $02 ;get vertical high nybble offset
lda #$23
sta ($06),y ;write blank metatile $23 to block buffer
lda #$10
sta BlockBounceTimer ;set block bounce timer
pla ;pull original metatile from stack
sta $05 ;and save here
ldy #$00 ;set default offset
lda CrouchingFlag ;is player crouching?
bne SmallBP ;if so, branch to increment offset
lda PlayerSize ;is player big?
beq BigBP ;if so, branch to use default offset
SmallBP: iny ;increment for small or big and crouching
BigBP: lda Player_Y_Position ;get player's vertical coordinate
clc
adc BlockYPosAdderData,y ;add value determined by size
and #$f0 ;mask out low nybble to get 16-pixel correspondence
sta Block_Y_Position,x ;save as vertical coordinate for block object
ldy Block_State,x ;get block object state
cpy #$11
beq Unbreak ;if set to value loaded for unbreakable, branch
jsr BrickShatter ;execute code for breakable brick
jmp InvOBit ;skip subroutine to do last part of code here
Unbreak: jsr BumpBlock ;execute code for unbreakable brick or question block
InvOBit: lda SprDataOffset_Ctrl ;invert control bit used by block objects
eor #$01 ;and floatey numbers
sta SprDataOffset_Ctrl
rts ;leave!
;--------------------------------
InitBlock_XY_Pos:
lda Player_X_Position ;get player's horizontal coordinate
clc
adc #$08 ;add eight pixels
and #$f0 ;mask out low nybble to give 16-pixel correspondence
sta Block_X_Position,x ;save as horizontal coordinate for block object
lda Player_PageLoc
adc #$00 ;add carry to page location of player
sta Block_PageLoc,x ;save as page location of block object
sta Block_PageLoc2,x ;save elsewhere to be used later
lda Player_Y_HighPos
sta Block_Y_HighPos,x ;save vertical high byte of player into
rts ;vertical high byte of block object and leave
;--------------------------------
BumpBlock:
jsr CheckTopOfBlock ;check to see if there's a coin directly above this block
lda #Sfx_Bump
sta Square1SoundQueue ;play bump sound
lda #$00
sta Block_X_Speed,x ;initialize horizontal speed for block object
sta Block_Y_MoveForce,x ;init fractional movement force
sta Player_Y_Speed ;init player's vertical speed
lda #$fe
sta Block_Y_Speed,x ;set vertical speed for block object
lda $05 ;get original metatile from stack
jsr BlockBumpedChk ;do a sub to check which block player bumped head on
bcc ExitBlockChk ;if no match was found, branch to leave
tya ;move block number to A
cmp #$09 ;if block number was within 0-8 range,
bcc BlockCode ;branch to use current number
sbc #$05 ;otherwise subtract 5 for second set to get proper number
BlockCode: jsr JumpEngine ;run appropriate subroutine depending on block number
.dw MushFlowerBlock
.dw CoinBlock
.dw CoinBlock
.dw ExtraLifeMushBlock
.dw MushFlowerBlock
.dw VineBlock
.dw StarBlock
.dw CoinBlock
.dw ExtraLifeMushBlock
;--------------------------------
MushFlowerBlock:
lda #$00 ;load mushroom/fire flower into power-up type
.db $2c ;BIT instruction opcode
StarBlock:
lda #$02 ;load star into power-up type
.db $2c ;BIT instruction opcode
ExtraLifeMushBlock:
lda #$03 ;load 1-up mushroom into power-up type
sta $39 ;store correct power-up type
jmp SetupPowerUp
VineBlock:
ldx #$05 ;load last slot for enemy object buffer
ldy SprDataOffset_Ctrl ;get control bit
jsr Setup_Vine ;set up vine object
ExitBlockChk:
rts ;leave
;--------------------------------
BrickQBlockMetatiles:
.db $c1, $c0, $5f, $60 ;used by question blocks
;these two sets are functionally identical, but look different
.db $55, $56, $57, $58, $59 ;used by ground level types
.db $5a, $5b, $5c, $5d, $5e ;used by other level types
BlockBumpedChk:
ldy #$0d ;start at end of metatile data
BumpChkLoop: cmp BrickQBlockMetatiles,y ;check to see if current metatile matches
beq MatchBump ;metatile found in block buffer, branch if so
dey ;otherwise move onto next metatile
bpl BumpChkLoop ;do this until all metatiles are checked
clc ;if none match, return with carry clear
MatchBump: rts ;note carry is set if found match
;--------------------------------
BrickShatter:
jsr CheckTopOfBlock ;check to see if there's a coin directly above this block
lda #Sfx_BrickShatter
sta Block_RepFlag,x ;set flag for block object to immediately replace metatile
sta NoiseSoundQueue ;load brick shatter sound
jsr SpawnBrickChunks ;create brick chunk objects
lda #$fe
sta Player_Y_Speed ;set vertical speed for player
lda #$05
sta DigitModifier+5 ;set digit modifier to give player 50 points
jsr AddToScore ;do sub to update the score
ldx SprDataOffset_Ctrl ;load control bit and leave
rts
;--------------------------------
CheckTopOfBlock:
ldx SprDataOffset_Ctrl ;load control bit
ldy $02 ;get vertical high nybble offset used in block buffer
beq TopEx ;branch to leave if set to zero, because we're at the top
tya ;otherwise set to A
sec
sbc #$10 ;subtract $10 to move up one row in the block buffer
sta $02 ;store as new vertical high nybble offset
tay
lda ($06),y ;get contents of block buffer in same column, one row up
cmp #$c2 ;is it a coin? (not underwater)
bne TopEx ;if not, branch to leave
lda #$00
sta ($06),y ;otherwise put blank metatile where coin was
jsr RemoveCoin_Axe ;write blank metatile to vram buffer
ldx SprDataOffset_Ctrl ;get control bit
jsr SetupJumpCoin ;create jumping coin object and update coin variables
TopEx: rts ;leave!
;--------------------------------
SpawnBrickChunks:
lda Block_X_Position,x ;set horizontal coordinate of block object
sta Block_Orig_XPos,x ;as original horizontal coordinate here
lda #$f0
sta Block_X_Speed,x ;set horizontal speed for brick chunk objects
sta Block_X_Speed+2,x
lda #$fa
sta Block_Y_Speed,x ;set vertical speed for one
lda #$fc
sta Block_Y_Speed+2,x ;set lower vertical speed for the other
lda #$00
sta Block_Y_MoveForce,x ;init fractional movement force for both
sta Block_Y_MoveForce+2,x
lda Block_PageLoc,x
sta Block_PageLoc+2,x ;copy page location
lda Block_X_Position,x
sta Block_X_Position+2,x ;copy horizontal coordinate
lda Block_Y_Position,x
clc ;add 8 pixels to vertical coordinate
adc #$08 ;and save as vertical coordinate for one of them
sta Block_Y_Position+2,x
lda #$fa
sta Block_Y_Speed,x ;set vertical speed...again??? (redundant)
rts
;-------------------------------------------------------------------------------------
BlockObjectsCore:
lda Block_State,x ;get state of block object
beq UpdSte ;if not set, branch to leave
and #$0f ;mask out high nybble
pha ;push to stack
tay ;put in Y for now
txa
clc
adc #$09 ;add 9 bytes to offset (note two block objects are created
tax ;when using brick chunks, but only one offset for both)
dey ;decrement Y to check for solid block state
beq BouncingBlockHandler ;branch if found, otherwise continue for brick chunks
jsr ImposeGravityBlock ;do sub to impose gravity on one block object object
jsr MoveObjectHorizontally ;do another sub to move horizontally
txa
clc ;move onto next block object
adc #$02
tax
jsr ImposeGravityBlock ;do sub to impose gravity on other block object
jsr MoveObjectHorizontally ;do another sub to move horizontally
ldx ObjectOffset ;get block object offset used for both
jsr RelativeBlockPosition ;get relative coordinates
jsr GetBlockOffscreenBits ;get offscreen information
jsr DrawBrickChunks ;draw the brick chunks
pla ;get lower nybble of saved state
ldy Block_Y_HighPos,x ;check vertical high byte of block object
beq UpdSte ;if above the screen, branch to kill it
pha ;otherwise save state back into stack
lda #$f0
cmp Block_Y_Position+2,x ;check to see if bottom block object went
bcs ChkTop ;to the bottom of the screen, and branch if not
sta Block_Y_Position+2,x ;otherwise set offscreen coordinate
ChkTop: lda Block_Y_Position,x ;get top block object's vertical coordinate
cmp #$f0 ;see if it went to the bottom of the screen
pla ;pull block object state from stack
bcc UpdSte ;if not, branch to save state
bcs KillBlock ;otherwise do unconditional branch to kill it
BouncingBlockHandler:
jsr ImposeGravityBlock ;do sub to impose gravity on block object
ldx ObjectOffset ;get block object offset
jsr RelativeBlockPosition ;get relative coordinates
jsr GetBlockOffscreenBits ;get offscreen information
jsr DrawBlock ;draw the block
lda Block_Y_Position,x ;get vertical coordinate
and #$0f ;mask out high nybble
cmp #$05 ;check to see if low nybble wrapped around
pla ;pull state from stack
bcs UpdSte ;if still above amount, not time to kill block yet, thus branch
lda #$01
sta Block_RepFlag,x ;otherwise set flag to replace metatile
KillBlock: lda #$00 ;if branched here, nullify object state
UpdSte: sta Block_State,x ;store contents of A in block object state
rts
;-------------------------------------------------------------------------------------
;$02 - used to store offset to block buffer
;$06-$07 - used to store block buffer address
BlockObjMT_Updater:
ldx #$01 ;set offset to start with second block object
UpdateLoop: stx ObjectOffset ;set offset here
lda VRAM_Buffer1 ;if vram buffer already being used here,
bne NextBUpd ;branch to move onto next block object
lda Block_RepFlag,x ;if flag for block object already clear,
beq NextBUpd ;branch to move onto next block object
lda Block_BBuf_Low,x ;get low byte of block buffer
sta $06 ;store into block buffer address
lda #$05
sta $07 ;set high byte of block buffer address
lda Block_Orig_YPos,x ;get original vertical coordinate of block object
sta $02 ;store here and use as offset to block buffer
tay
lda Block_Metatile,x ;get metatile to be written
sta ($06),y ;write it to the block buffer
jsr ReplaceBlockMetatile ;do sub to replace metatile where block object is
lda #$00
sta Block_RepFlag,x ;clear block object flag
NextBUpd: dex ;decrement block object offset
bpl UpdateLoop ;do this until both block objects are dealt with
rts ;then leave
;-------------------------------------------------------------------------------------
;$00 - used to store high nybble of horizontal speed as adder
;$01 - used to store low nybble of horizontal speed
;$02 - used to store adder to page location
MoveEnemyHorizontally:
inx ;increment offset for enemy offset
jsr MoveObjectHorizontally ;position object horizontally according to
ldx ObjectOffset ;counters, return with saved value in A,
rts ;put enemy offset back in X and leave
MovePlayerHorizontally:
lda JumpspringAnimCtrl ;if jumpspring currently animating,
bne ExXMove ;branch to leave
tax ;otherwise set zero for offset to use player's stuff
MoveObjectHorizontally:
lda SprObject_X_Speed,x ;get currently saved value (horizontal
asl ;speed, secondary counter, whatever)
asl ;and move low nybble to high
asl
asl
sta $01 ;store result here
lda SprObject_X_Speed,x ;get saved value again
lsr ;move high nybble to low
lsr
lsr
lsr
cmp #$08 ;if < 8, branch, do not change
bcc SaveXSpd
ora #%11110000 ;otherwise alter high nybble
SaveXSpd: sta $00 ;save result here
ldy #$00 ;load default Y value here
cmp #$00 ;if result positive, leave Y alone
bpl UseAdder
dey ;otherwise decrement Y
UseAdder: sty $02 ;save Y here
lda SprObject_X_MoveForce,x ;get whatever number's here
clc
adc $01 ;add low nybble moved to high
sta SprObject_X_MoveForce,x ;store result here
lda #$00 ;init A
rol ;rotate carry into d0
pha ;push onto stack
ror ;rotate d0 back onto carry
lda SprObject_X_Position,x
adc $00 ;add carry plus saved value (high nybble moved to low
sta SprObject_X_Position,x ;plus $f0 if necessary) to object's horizontal position
lda SprObject_PageLoc,x
adc $02 ;add carry plus other saved value to the
sta SprObject_PageLoc,x ;object's page location and save
pla
clc ;pull old carry from stack and add
adc $00 ;to high nybble moved to low
ExXMove: rts ;and leave
;-------------------------------------------------------------------------------------
;$00 - used for downward force
;$01 - used for upward force
;$02 - used for maximum vertical speed
MovePlayerVertically:
ldx #$00 ;set X for player offset
lda TimerControl
bne NoJSChk ;if master timer control set, branch ahead
lda JumpspringAnimCtrl ;otherwise check to see if jumpspring is animating
bne ExXMove ;branch to leave if so
NoJSChk: lda VerticalForce ;dump vertical force
sta $00
lda #$04 ;set maximum vertical speed here
jmp ImposeGravitySprObj ;then jump to move player vertically
;--------------------------------
MoveD_EnemyVertically:
ldy #$3d ;set quick movement amount downwards
lda Enemy_State,x ;then check enemy state
cmp #$05 ;if not set to unique state for spiny's egg, go ahead
bne ContVMove ;and use, otherwise set different movement amount, continue on
MoveFallingPlatform:
ldy #$20 ;set movement amount
ContVMove: jmp SetHiMax ;jump to skip the rest of this
;--------------------------------
MoveRedPTroopaDown:
ldy #$00 ;set Y to move downwards
jmp MoveRedPTroopa ;skip to movement routine
MoveRedPTroopaUp:
ldy #$01 ;set Y to move upwards
MoveRedPTroopa:
inx ;increment X for enemy offset
lda #$03
sta $00 ;set downward movement amount here
lda #$06
sta $01 ;set upward movement amount here
lda #$02
sta $02 ;set maximum speed here
tya ;set movement direction in A, and
jmp RedPTroopaGrav ;jump to move this thing
;--------------------------------
MoveDropPlatform:
ldy #$7f ;set movement amount for drop platform
bne SetMdMax ;skip ahead of other value set here
MoveEnemySlowVert:
ldy #$0f ;set movement amount for bowser/other objects
SetMdMax: lda #$02 ;set maximum speed in A
bne SetXMoveAmt ;unconditional branch
;--------------------------------
MoveJ_EnemyVertically:
ldy #$1c ;set movement amount for podoboo/other objects
SetHiMax: lda #$03 ;set maximum speed in A
SetXMoveAmt: sty $00 ;set movement amount here
inx ;increment X for enemy offset
jsr ImposeGravitySprObj ;do a sub to move enemy object downwards
ldx ObjectOffset ;get enemy object buffer offset and leave
rts
;--------------------------------
MaxSpdBlockData:
.db $06, $08
ResidualGravityCode:
ldy #$00 ;this part appears to be residual,
.db $2c ;no code branches or jumps to it...
ImposeGravityBlock:
ldy #$01 ;set offset for maximum speed
lda #$50 ;set movement amount here
sta $00
lda MaxSpdBlockData,y ;get maximum speed
ImposeGravitySprObj:
sta $02 ;set maximum speed here
lda #$00 ;set value to move downwards
jmp ImposeGravity ;jump to the code that actually moves it
;--------------------------------
MovePlatformDown:
lda #$00 ;save value to stack (if branching here, execute next
.db $2c ;part as BIT instruction)
MovePlatformUp:
lda #$01 ;save value to stack
pha
ldy Enemy_ID,x ;get enemy object identifier
inx ;increment offset for enemy object
lda #$05 ;load default value here
cpy #$29 ;residual comparison, object #29 never executes
bne SetDplSpd ;this code, thus unconditional branch here
lda #$09 ;residual code
SetDplSpd: sta $00 ;save downward movement amount here
lda #$0a ;save upward movement amount here
sta $01
lda #$03 ;save maximum vertical speed here
sta $02
pla ;get value from stack
tay ;use as Y, then move onto code shared by red koopa
RedPTroopaGrav:
jsr ImposeGravity ;do a sub to move object gradually
ldx ObjectOffset ;get enemy object offset and leave
rts
;-------------------------------------------------------------------------------------
;$00 - used for downward force
;$01 - used for upward force
;$07 - used as adder for vertical position
ImposeGravity:
pha ;push value to stack
lda SprObject_YMF_Dummy,x
clc ;add value in movement force to contents of dummy variable
adc SprObject_Y_MoveForce,x
sta SprObject_YMF_Dummy,x
ldy #$00 ;set Y to zero by default
lda SprObject_Y_Speed,x ;get current vertical speed
bpl AlterYP ;if currently moving downwards, do not decrement Y
dey ;otherwise decrement Y
AlterYP: sty $07 ;store Y here
adc SprObject_Y_Position,x ;add vertical position to vertical speed plus carry
sta SprObject_Y_Position,x ;store as new vertical position
lda SprObject_Y_HighPos,x
adc $07 ;add carry plus contents of $07 to vertical high byte
sta SprObject_Y_HighPos,x ;store as new vertical high byte
lda SprObject_Y_MoveForce,x
clc
adc $00 ;add downward movement amount to contents of $0433
sta SprObject_Y_MoveForce,x
lda SprObject_Y_Speed,x ;add carry to vertical speed and store
adc #$00
sta SprObject_Y_Speed,x
cmp $02 ;compare to maximum speed
bmi ChkUpM ;if less than preset value, skip this part
lda SprObject_Y_MoveForce,x
cmp #$80 ;if less positively than preset maximum, skip this part
bcc ChkUpM
lda $02
sta SprObject_Y_Speed,x ;keep vertical speed within maximum value
lda #$00
sta SprObject_Y_MoveForce,x ;clear fractional
ChkUpM: pla ;get value from stack
beq ExVMove ;if set to zero, branch to leave
lda $02
eor #%11111111 ;otherwise get two's compliment of maximum speed
tay
iny
sty $07 ;store two's compliment here
lda SprObject_Y_MoveForce,x
sec ;subtract upward movement amount from contents
sbc $01 ;of movement force, note that $01 is twice as large as $00,
sta SprObject_Y_MoveForce,x ;thus it effectively undoes add we did earlier
lda SprObject_Y_Speed,x
sbc #$00 ;subtract borrow from vertical speed and store
sta SprObject_Y_Speed,x
cmp $07 ;compare vertical speed to two's compliment
bpl ExVMove ;if less negatively than preset maximum, skip this part
lda SprObject_Y_MoveForce,x
cmp #$80 ;check if fractional part is above certain amount,
bcs ExVMove ;and if so, branch to leave
lda $07
sta SprObject_Y_Speed,x ;keep vertical speed within maximum value
lda #$ff
sta SprObject_Y_MoveForce,x ;clear fractional
ExVMove: rts ;leave!
;-------------------------------------------------------------------------------------
EnemiesAndLoopsCore:
lda Enemy_Flag,x ;check data here for MSB set
pha ;save in stack
asl
bcs ChkBowserF ;if MSB set in enemy flag, branch ahead of jumps
pla ;get from stack
beq ChkAreaTsk ;if data zero, branch
jmp RunEnemyObjectsCore ;otherwise, jump to run enemy subroutines
ChkAreaTsk: lda AreaParserTaskNum ;check number of tasks to perform
and #$07
cmp #$07 ;if at a specific task, jump and leave
beq ExitELCore
jmp ProcLoopCommand ;otherwise, jump to process loop command/load enemies
ChkBowserF: pla ;get data from stack
and #%00001111 ;mask out high nybble
tay
lda Enemy_Flag,y ;use as pointer and load same place with different offset
bne ExitELCore
sta Enemy_Flag,x ;if second enemy flag not set, also clear first one
ExitELCore: rts
;--------------------------------
;loop command data
LoopCmdWorldNumber:
.db $03, $03, $06, $06, $06, $06, $06, $06, $07, $07, $07
LoopCmdPageNumber:
.db $05, $09, $04, $05, $06, $08, $09, $0a, $06, $0b, $10
LoopCmdYPosition:
.db $40, $b0, $b0, $80, $40, $40, $80, $40, $f0, $f0, $f0
ExecGameLoopback:
lda Player_PageLoc ;send player back four pages
sec
sbc #$04
sta Player_PageLoc
lda CurrentPageLoc ;send current page back four pages
sec
sbc #$04
sta CurrentPageLoc
lda ScreenLeft_PageLoc ;subtract four from page location
sec ;of screen's left border
sbc #$04
sta ScreenLeft_PageLoc
lda ScreenRight_PageLoc ;do the same for the page location
sec ;of screen's right border
sbc #$04
sta ScreenRight_PageLoc
lda AreaObjectPageLoc ;subtract four from page control
sec ;for area objects
sbc #$04
sta AreaObjectPageLoc
lda #$00 ;initialize page select for both
sta EnemyObjectPageSel ;area and enemy objects
sta AreaObjectPageSel
sta EnemyDataOffset ;initialize enemy object data offset
sta EnemyObjectPageLoc ;and enemy object page control
lda AreaDataOfsLoopback,y ;adjust area object offset based on
sta AreaDataOffset ;which loop command we encountered
rts
ProcLoopCommand:
lda LoopCommand ;check if loop command was found
beq ChkEnemyFrenzy
lda CurrentColumnPos ;check to see if we're still on the first page
bne ChkEnemyFrenzy ;if not, do not loop yet
ldy #$0b ;start at the end of each set of loop data
FindLoop: dey
bmi ChkEnemyFrenzy ;if all data is checked and not match, do not loop
lda WorldNumber ;check to see if one of the world numbers
cmp LoopCmdWorldNumber,y ;matches our current world number
bne FindLoop
lda CurrentPageLoc ;check to see if one of the page numbers
cmp LoopCmdPageNumber,y ;matches the page we're currently on
bne FindLoop
lda Player_Y_Position ;check to see if the player is at the correct position
cmp LoopCmdYPosition,y ;if not, branch to check for world 7
bne WrongChk
lda Player_State ;check to see if the player is
cmp #$00 ;on solid ground (i.e. not jumping or falling)
bne WrongChk ;if not, player fails to pass loop, and loopback
lda WorldNumber ;are we in world 7? (check performed on correct
cmp #World7 ;vertical position and on solid ground)
bne InitMLp ;if not, initialize flags used there, otherwise
inc MultiLoopCorrectCntr ;increment counter for correct progression
IncMLoop: inc MultiLoopPassCntr ;increment master multi-part counter
lda MultiLoopPassCntr ;have we done all three parts?
cmp #$03
bne InitLCmd ;if not, skip this part
lda MultiLoopCorrectCntr ;if so, have we done them all correctly?
cmp #$03
beq InitMLp ;if so, branch past unnecessary check here
bne DoLpBack ;unconditional branch if previous branch fails
WrongChk: lda WorldNumber ;are we in world 7? (check performed on
cmp #World7 ;incorrect vertical position or not on solid ground)
beq IncMLoop
DoLpBack: jsr ExecGameLoopback ;if player is not in right place, loop back
jsr KillAllEnemies
InitMLp: lda #$00 ;initialize counters used for multi-part loop commands
sta MultiLoopPassCntr
sta MultiLoopCorrectCntr
InitLCmd: lda #$00 ;initialize loop command flag
sta LoopCommand
;--------------------------------
ChkEnemyFrenzy:
lda EnemyFrenzyQueue ;check for enemy object in frenzy queue
beq ProcessEnemyData ;if not, skip this part
sta Enemy_ID,x ;store as enemy object identifier here
lda #$01
sta Enemy_Flag,x ;activate enemy object flag
lda #$00
sta Enemy_State,x ;initialize state and frenzy queue
sta EnemyFrenzyQueue
jmp InitEnemyObject ;and then jump to deal with this enemy
;--------------------------------
;$06 - used to hold page location of extended right boundary
;$07 - used to hold high nybble of position of extended right boundary
ProcessEnemyData:
ldy EnemyDataOffset ;get offset of enemy object data
lda (EnemyData),y ;load first byte
cmp #$ff ;check for EOD terminator
bne CheckEndofBuffer
jmp CheckFrenzyBuffer ;if found, jump to check frenzy buffer, otherwise
CheckEndofBuffer:
and #%00001111 ;check for special row $0e
cmp #$0e
beq CheckRightBounds ;if found, branch, otherwise
cpx #$05 ;check for end of buffer
bcc CheckRightBounds ;if not at end of buffer, branch
iny
lda (EnemyData),y ;check for specific value here
and #%00111111 ;not sure what this was intended for, exactly
cmp #$2e ;this part is quite possibly residual code
beq CheckRightBounds ;but it has the effect of keeping enemies out of
rts ;the sixth slot
CheckRightBounds:
lda ScreenRight_X_Pos ;add 48 to pixel coordinate of right boundary
clc
adc #$30
and #%11110000 ;store high nybble
sta $07
lda ScreenRight_PageLoc ;add carry to page location of right boundary
adc #$00
sta $06 ;store page location + carry
ldy EnemyDataOffset
iny
lda (EnemyData),y ;if MSB of enemy object is clear, branch to check for row $0f
asl
bcc CheckPageCtrlRow
lda EnemyObjectPageSel ;if page select already set, do not set again
bne CheckPageCtrlRow
inc EnemyObjectPageSel ;otherwise, if MSB is set, set page select
inc EnemyObjectPageLoc ;and increment page control
CheckPageCtrlRow:
dey
lda (EnemyData),y ;reread first byte
and #$0f
cmp #$0f ;check for special row $0f
bne PositionEnemyObj ;if not found, branch to position enemy object
lda EnemyObjectPageSel ;if page select set,
bne PositionEnemyObj ;branch without reading second byte
iny
lda (EnemyData),y ;otherwise, get second byte, mask out 2 MSB
and #%00111111
sta EnemyObjectPageLoc ;store as page control for enemy object data
inc EnemyDataOffset ;increment enemy object data offset 2 bytes
inc EnemyDataOffset
inc EnemyObjectPageSel ;set page select for enemy object data and
jmp ProcLoopCommand ;jump back to process loop commands again
PositionEnemyObj:
lda EnemyObjectPageLoc ;store page control as page location
sta Enemy_PageLoc,x ;for enemy object
lda (EnemyData),y ;get first byte of enemy object
and #%11110000
sta Enemy_X_Position,x ;store column position
cmp ScreenRight_X_Pos ;check column position against right boundary
lda Enemy_PageLoc,x ;without subtracting, then subtract borrow
sbc ScreenRight_PageLoc ;from page location
bcs CheckRightExtBounds ;if enemy object beyond or at boundary, branch
lda (EnemyData),y
and #%00001111 ;check for special row $0e
cmp #$0e ;if found, jump elsewhere
beq ParseRow0e
jmp CheckThreeBytes ;if not found, unconditional jump
CheckRightExtBounds:
lda $07 ;check right boundary + 48 against
cmp Enemy_X_Position,x ;column position without subtracting,
lda $06 ;then subtract borrow from page control temp
sbc Enemy_PageLoc,x ;plus carry
bcc CheckFrenzyBuffer ;if enemy object beyond extended boundary, branch
lda #$01 ;store value in vertical high byte
sta Enemy_Y_HighPos,x
lda (EnemyData),y ;get first byte again
asl ;multiply by four to get the vertical
asl ;coordinate
asl
asl
sta Enemy_Y_Position,x
cmp #$e0 ;do one last check for special row $0e
beq ParseRow0e ;(necessary if branched to $c1cb)
iny
lda (EnemyData),y ;get second byte of object
and #%01000000 ;check to see if hard mode bit is set
beq CheckForEnemyGroup ;if not, branch to check for group enemy objects
lda SecondaryHardMode ;if set, check to see if secondary hard mode flag
beq Inc2B ;is on, and if not, branch to skip this object completely
CheckForEnemyGroup:
lda (EnemyData),y ;get second byte and mask out 2 MSB
and #%00111111
cmp #$37 ;check for value below $37
bcc BuzzyBeetleMutate
cmp #$3f ;if $37 or greater, check for value
bcc DoGroup ;below $3f, branch if below $3f
BuzzyBeetleMutate:
cmp #Goomba ;if below $37, check for goomba
bne StrID ;value ($3f or more always fails)
ldy PrimaryHardMode ;check if primary hard mode flag is set
beq StrID ;and if so, change goomba to buzzy beetle
lda #BuzzyBeetle
StrID: sta Enemy_ID,x ;store enemy object number into buffer
lda #$01
sta Enemy_Flag,x ;set flag for enemy in buffer
jsr InitEnemyObject
lda Enemy_Flag,x ;check to see if flag is set
bne Inc2B ;if not, leave, otherwise branch
rts
CheckFrenzyBuffer:
lda EnemyFrenzyBuffer ;if enemy object stored in frenzy buffer
bne StrFre ;then branch ahead to store in enemy object buffer
lda VineFlagOffset ;otherwise check vine flag offset
cmp #$01
bne ExEPar ;if other value <> 1, leave
lda #VineObject ;otherwise put vine in enemy identifier
StrFre: sta Enemy_ID,x ;store contents of frenzy buffer into enemy identifier value
InitEnemyObject:
lda #$00 ;initialize enemy state
sta Enemy_State,x
jsr CheckpointEnemyID ;jump ahead to run jump engine and subroutines
ExEPar: rts ;then leave
DoGroup:
jmp HandleGroupEnemies ;handle enemy group objects
ParseRow0e:
iny ;increment Y to load third byte of object
iny
lda (EnemyData),y
lsr ;move 3 MSB to the bottom, effectively
lsr ;making %xxx00000 into %00000xxx
lsr
lsr
lsr
cmp WorldNumber ;is it the same world number as we're on?
bne NotUse ;if not, do not use (this allows multiple uses
dey ;of the same area, like the underground bonus areas)
lda (EnemyData),y ;otherwise, get second byte and use as offset
sta AreaPointer ;to addresses for level and enemy object data
iny
lda (EnemyData),y ;get third byte again, and this time mask out
and #%00011111 ;the 3 MSB from before, save as page number to be
sta EntrancePage ;used upon entry to area, if area is entered
NotUse: jmp Inc3B
CheckThreeBytes:
ldy EnemyDataOffset ;load current offset for enemy object data
lda (EnemyData),y ;get first byte
and #%00001111 ;check for special row $0e
cmp #$0e
bne Inc2B
Inc3B: inc EnemyDataOffset ;if row = $0e, increment three bytes
Inc2B: inc EnemyDataOffset ;otherwise increment two bytes
inc EnemyDataOffset
lda #$00 ;init page select for enemy objects
sta EnemyObjectPageSel
ldx ObjectOffset ;reload current offset in enemy buffers
rts ;and leave
CheckpointEnemyID:
lda Enemy_ID,x
cmp #$15 ;check enemy object identifier for $15 or greater
bcs InitEnemyRoutines ;and branch straight to the jump engine if found
tay ;save identifier in Y register for now
lda Enemy_Y_Position,x
adc #$08 ;add eight pixels to what will eventually be the
sta Enemy_Y_Position,x ;enemy object's vertical coordinate ($00-$14 only)
lda #$01
sta EnemyOffscrBitsMasked,x ;set offscreen masked bit
tya ;get identifier back and use as offset for jump engine
InitEnemyRoutines:
jsr JumpEngine
;jump engine table for newly loaded enemy objects
.dw InitNormalEnemy ;for objects $00-$0f
.dw InitNormalEnemy
.dw InitNormalEnemy
.dw InitRedKoopa
.dw NoInitCode
.dw InitHammerBro
.dw InitGoomba
.dw InitBloober
.dw InitBulletBill
.dw NoInitCode
.dw InitCheepCheep
.dw InitCheepCheep
.dw InitPodoboo
.dw InitPiranhaPlant
.dw InitJumpGPTroopa
.dw InitRedPTroopa
.dw InitHorizFlySwimEnemy ;for objects $10-$1f
.dw InitLakitu
.dw InitEnemyFrenzy
.dw NoInitCode
.dw InitEnemyFrenzy
.dw InitEnemyFrenzy
.dw InitEnemyFrenzy
.dw InitEnemyFrenzy
.dw EndFrenzy
.dw NoInitCode
.dw NoInitCode
.dw InitShortFirebar
.dw InitShortFirebar
.dw InitShortFirebar
.dw InitShortFirebar
.dw InitLongFirebar
.dw NoInitCode ;for objects $20-$2f
.dw NoInitCode
.dw NoInitCode
.dw NoInitCode
.dw InitBalPlatform
.dw InitVertPlatform
.dw LargeLiftUp
.dw LargeLiftDown
.dw InitHoriPlatform
.dw InitDropPlatform
.dw InitHoriPlatform
.dw PlatLiftUp
.dw PlatLiftDown
.dw InitBowser
.dw PwrUpJmp ;possibly dummy value
.dw Setup_Vine
.dw NoInitCode ;for objects $30-$36
.dw NoInitCode
.dw NoInitCode
.dw NoInitCode
.dw NoInitCode
.dw InitRetainerObj
.dw EndOfEnemyInitCode
;-------------------------------------------------------------------------------------
NoInitCode:
rts ;this executed when enemy object has no init code
;--------------------------------
InitGoomba:
jsr InitNormalEnemy ;set appropriate horizontal speed
jmp SmallBBox ;set $09 as bounding box control, set other values
;--------------------------------
InitPodoboo:
lda #$02 ;set enemy position to below
sta Enemy_Y_HighPos,x ;the bottom of the screen
sta Enemy_Y_Position,x
lsr
sta EnemyIntervalTimer,x ;set timer for enemy
lsr
sta Enemy_State,x ;initialize enemy state, then jump to use
jmp SmallBBox ;$09 as bounding box size and set other things
;--------------------------------
InitRetainerObj:
lda #$b8 ;set fixed vertical position for
sta Enemy_Y_Position,x ;princess/mushroom retainer object
rts
;--------------------------------
NormalXSpdData:
.db $f8, $f4
InitNormalEnemy:
ldy #$01 ;load offset of 1 by default
lda PrimaryHardMode ;check for primary hard mode flag set
bne GetESpd
dey ;if not set, decrement offset
GetESpd: lda NormalXSpdData,y ;get appropriate horizontal speed
SetESpd: sta Enemy_X_Speed,x ;store as speed for enemy object
jmp TallBBox ;branch to set bounding box control and other data
;--------------------------------
InitRedKoopa:
jsr InitNormalEnemy ;load appropriate horizontal speed
lda #$01 ;set enemy state for red koopa troopa $03
sta Enemy_State,x
rts
;--------------------------------
HBroWalkingTimerData:
.db $80, $50
InitHammerBro:
lda #$00 ;init horizontal speed and timer used by hammer bro
sta HammerThrowingTimer,x ;apparently to time hammer throwing
sta Enemy_X_Speed,x
ldy SecondaryHardMode ;get secondary hard mode flag
lda HBroWalkingTimerData,y
sta EnemyIntervalTimer,x ;set value as delay for hammer bro to walk left
lda #$0b ;set specific value for bounding box size control
jmp SetBBox
;--------------------------------
InitHorizFlySwimEnemy:
lda #$00 ;initialize horizontal speed
jmp SetESpd
;--------------------------------
InitBloober:
lda #$00 ;initialize horizontal speed
sta BlooperMoveSpeed,x
SmallBBox: lda #$09 ;set specific bounding box size control
bne SetBBox ;unconditional branch
;--------------------------------
InitRedPTroopa:
ldy #$30 ;load central position adder for 48 pixels down
lda Enemy_Y_Position,x ;set vertical coordinate into location to
sta RedPTroopaOrigXPos,x ;be used as original vertical coordinate
bpl GetCent ;if vertical coordinate < $80
ldy #$e0 ;if => $80, load position adder for 32 pixels up
GetCent: tya ;send central position adder to A
adc Enemy_Y_Position,x ;add to current vertical coordinate
sta RedPTroopaCenterYPos,x ;store as central vertical coordinate
TallBBox: lda #$03 ;set specific bounding box size control
SetBBox: sta Enemy_BoundBoxCtrl,x ;set bounding box control here
lda #$02 ;set moving direction for left
sta Enemy_MovingDir,x
InitVStf: lda #$00 ;initialize vertical speed
sta Enemy_Y_Speed,x ;and movement force
sta Enemy_Y_MoveForce,x
rts
;--------------------------------
InitBulletBill:
lda #$02 ;set moving direction for left
sta Enemy_MovingDir,x
lda #$09 ;set bounding box control for $09
sta Enemy_BoundBoxCtrl,x
rts
;--------------------------------
InitCheepCheep:
jsr SmallBBox ;set vertical bounding box, speed, init others
lda PseudoRandomBitReg,x ;check one portion of LSFR
and #%00010000 ;get d4 from it
sta CheepCheepMoveMFlag,x ;save as movement flag of some sort
lda Enemy_Y_Position,x
sta CheepCheepOrigYPos,x ;save original vertical coordinate here
rts
;--------------------------------
InitLakitu:
lda EnemyFrenzyBuffer ;check to see if an enemy is already in
bne KillLakitu ;the frenzy buffer, and branch to kill lakitu if so
SetupLakitu:
lda #$00 ;erase counter for lakitu's reappearance
sta LakituReappearTimer
jsr InitHorizFlySwimEnemy ;set $03 as bounding box, set other attributes
jmp TallBBox2 ;set $03 as bounding box again (not necessary) and leave
KillLakitu:
jmp EraseEnemyObject
;--------------------------------
;$01-$03 - used to hold pseudorandom difference adjusters
PRDiffAdjustData:
.db $26, $2c, $32, $38
.db $20, $22, $24, $26
.db $13, $14, $15, $16
LakituAndSpinyHandler:
lda FrenzyEnemyTimer ;if timer here not expired, leave
bne ExLSHand
cpx #$05 ;if we are on the special use slot, leave
bcs ExLSHand
lda #$80 ;set timer
sta FrenzyEnemyTimer
ldy #$04 ;start with the last enemy slot
ChkLak: lda Enemy_ID,y ;check all enemy slots to see
cmp #Lakitu ;if lakitu is on one of them
beq CreateSpiny ;if so, branch out of this loop
dey ;otherwise check another slot
bpl ChkLak ;loop until all slots are checked
inc LakituReappearTimer ;increment reappearance timer
lda LakituReappearTimer
cmp #$07 ;check to see if we're up to a certain value yet
bcc ExLSHand ;if not, leave
ldx #$04 ;start with the last enemy slot again
ChkNoEn: lda Enemy_Flag,x ;check enemy buffer flag for non-active enemy slot
beq CreateL ;branch out of loop if found
dex ;otherwise check next slot
bpl ChkNoEn ;branch until all slots are checked
bmi RetEOfs ;if no empty slots were found, branch to leave
CreateL: lda #$00 ;initialize enemy state
sta Enemy_State,x
lda #Lakitu ;create lakitu enemy object
sta Enemy_ID,x
jsr SetupLakitu ;do a sub to set up lakitu
lda #$20
jsr PutAtRightExtent ;finish setting up lakitu
RetEOfs: ldx ObjectOffset ;get enemy object buffer offset again and leave
ExLSHand: rts
;--------------------------------
CreateSpiny:
lda Player_Y_Position ;if player above a certain point, branch to leave
cmp #$2c
bcc ExLSHand
lda Enemy_State,y ;if lakitu is not in normal state, branch to leave
bne ExLSHand
lda Enemy_PageLoc,y ;store horizontal coordinates (high and low) of lakitu
sta Enemy_PageLoc,x ;into the coordinates of the spiny we're going to create
lda Enemy_X_Position,y
sta Enemy_X_Position,x
lda #$01 ;put spiny within vertical screen unit
sta Enemy_Y_HighPos,x
lda Enemy_Y_Position,y ;put spiny eight pixels above where lakitu is
sec
sbc #$08
sta Enemy_Y_Position,x
lda PseudoRandomBitReg,x ;get 2 LSB of LSFR and save to Y
and #%00000011
tay
ldx #$02
DifLoop: lda PRDiffAdjustData,y ;get three values and save them
sta $01,x ;to $01-$03
iny
iny ;increment Y four bytes for each value
iny
iny
dex ;decrement X for each one
bpl DifLoop ;loop until all three are written
ldx ObjectOffset ;get enemy object buffer offset
jsr PlayerLakituDiff ;move enemy, change direction, get value - difference
ldy Player_X_Speed ;check player's horizontal speed
cpy #$08
bcs SetSpSpd ;if moving faster than a certain amount, branch elsewhere
tay ;otherwise save value in A to Y for now
lda PseudoRandomBitReg+1,x
and #%00000011 ;get one of the LSFR parts and save the 2 LSB
beq UsePosv ;branch if neither bits are set
tya
eor #%11111111 ;otherwise get two's compliment of Y
tay
iny
UsePosv: tya ;put value from A in Y back to A (they will be lost anyway)
SetSpSpd: jsr SmallBBox ;set bounding box control, init attributes, lose contents of A
ldy #$02
sta Enemy_X_Speed,x ;set horizontal speed to zero because previous contents
cmp #$00 ;of A were lost...branch here will never be taken for
bmi SpinyRte ;the same reason
dey
SpinyRte: sty Enemy_MovingDir,x ;set moving direction to the right
lda #$fd
sta Enemy_Y_Speed,x ;set vertical speed to move upwards
lda #$01
sta Enemy_Flag,x ;enable enemy object by setting flag
lda #$05
sta Enemy_State,x ;put spiny in egg state and leave
ChpChpEx: rts
;--------------------------------
FirebarSpinSpdData:
.db $28, $38, $28, $38, $28
FirebarSpinDirData:
.db $00, $00, $10, $10, $00
InitLongFirebar:
jsr DuplicateEnemyObj ;create enemy object for long firebar
InitShortFirebar:
lda #$00 ;initialize low byte of spin state
sta FirebarSpinState_Low,x
lda Enemy_ID,x ;subtract $1b from enemy identifier
sec ;to get proper offset for firebar data
sbc #$1b
tay
lda FirebarSpinSpdData,y ;get spinning speed of firebar
sta FirebarSpinSpeed,x
lda FirebarSpinDirData,y ;get spinning direction of firebar
sta FirebarSpinDirection,x
lda Enemy_Y_Position,x
clc ;add four pixels to vertical coordinate
adc #$04
sta Enemy_Y_Position,x
lda Enemy_X_Position,x
clc ;add four pixels to horizontal coordinate
adc #$04
sta Enemy_X_Position,x
lda Enemy_PageLoc,x
adc #$00 ;add carry to page location
sta Enemy_PageLoc,x
jmp TallBBox2 ;set bounding box control (not used) and leave
;--------------------------------
;$00-$01 - used to hold pseudorandom bits
FlyCCXPositionData:
.db $80, $30, $40, $80
.db $30, $50, $50, $70
.db $20, $40, $80, $a0
.db $70, $40, $90, $68
FlyCCXSpeedData:
.db $0e, $05, $06, $0e
.db $1c, $20, $10, $0c
.db $1e, $22, $18, $14
FlyCCTimerData:
.db $10, $60, $20, $48
InitFlyingCheepCheep:
lda FrenzyEnemyTimer ;if timer here not expired yet, branch to leave
bne ChpChpEx
jsr SmallBBox ;jump to set bounding box size $09 and init other values
lda PseudoRandomBitReg+1,x
and #%00000011 ;set pseudorandom offset here
tay
lda FlyCCTimerData,y ;load timer with pseudorandom offset
sta FrenzyEnemyTimer
ldy #$03 ;load Y with default value
lda SecondaryHardMode
beq MaxCC ;if secondary hard mode flag not set, do not increment Y
iny ;otherwise, increment Y to allow as many as four onscreen
MaxCC: sty $00 ;store whatever pseudorandom bits are in Y
cpx $00 ;compare enemy object buffer offset with Y
bcs ChpChpEx ;if X => Y, branch to leave
lda PseudoRandomBitReg,x
and #%00000011 ;get last two bits of LSFR, first part
sta $00 ;and store in two places
sta $01
lda #$fb ;set vertical speed for cheep-cheep
sta Enemy_Y_Speed,x
lda #$00 ;load default value
ldy Player_X_Speed ;check player's horizontal speed
beq GSeed ;if player not moving left or right, skip this part
lda #$04
cpy #$19 ;if moving to the right but not very quickly,
bcc GSeed ;do not change A
asl ;otherwise, multiply A by 2
GSeed: pha ;save to stack
clc
adc $00 ;add to last two bits of LSFR we saved earlier
sta $00 ;save it there
lda PseudoRandomBitReg+1,x
and #%00000011 ;if neither of the last two bits of second LSFR set,
beq RSeed ;skip this part and save contents of $00
lda PseudoRandomBitReg+2,x
and #%00001111 ;otherwise overwrite with lower nybble of
sta $00 ;third LSFR part
RSeed: pla ;get value from stack we saved earlier
clc
adc $01 ;add to last two bits of LSFR we saved in other place
tay ;use as pseudorandom offset here
lda FlyCCXSpeedData,y ;get horizontal speed using pseudorandom offset
sta Enemy_X_Speed,x
lda #$01 ;set to move towards the right
sta Enemy_MovingDir,x
lda Player_X_Speed ;if player moving left or right, branch ahead of this part
bne D2XPos1
ldy $00 ;get first LSFR or third LSFR lower nybble
tya ;and check for d1 set
and #%00000010
beq D2XPos1 ;if d1 not set, branch
lda Enemy_X_Speed,x
eor #$ff ;if d1 set, change horizontal speed
clc ;into two's compliment, thus moving in the opposite
adc #$01 ;direction
sta Enemy_X_Speed,x
inc Enemy_MovingDir,x ;increment to move towards the left
D2XPos1: tya ;get first LSFR or third LSFR lower nybble again
and #%00000010
beq D2XPos2 ;check for d1 set again, branch again if not set
lda Player_X_Position ;get player's horizontal position
clc
adc FlyCCXPositionData,y ;if d1 set, add value obtained from pseudorandom offset
sta Enemy_X_Position,x ;and save as enemy's horizontal position
lda Player_PageLoc ;get player's page location
adc #$00 ;add carry and jump past this part
jmp FinCCSt
D2XPos2: lda Player_X_Position ;get player's horizontal position
sec
sbc FlyCCXPositionData,y ;if d1 not set, subtract value obtained from pseudorandom
sta Enemy_X_Position,x ;offset and save as enemy's horizontal position
lda Player_PageLoc ;get player's page location
sbc #$00 ;subtract borrow
FinCCSt: sta Enemy_PageLoc,x ;save as enemy's page location
lda #$01
sta Enemy_Flag,x ;set enemy's buffer flag
sta Enemy_Y_HighPos,x ;set enemy's high vertical byte
lda #$f8
sta Enemy_Y_Position,x ;put enemy below the screen, and we are done
rts
;--------------------------------
InitBowser:
jsr DuplicateEnemyObj ;jump to create another bowser object
stx BowserFront_Offset ;save offset of first here
lda #$00
sta BowserBodyControls ;initialize bowser's body controls
sta BridgeCollapseOffset ;and bridge collapse offset
lda Enemy_X_Position,x
sta BowserOrigXPos ;store original horizontal position here
lda #$df
sta BowserFireBreathTimer ;store something here
sta Enemy_MovingDir,x ;and in moving direction
lda #$20
sta BowserFeetCounter ;set bowser's feet timer and in enemy timer
sta EnemyFrameTimer,x
lda #$05
sta BowserHitPoints ;give bowser 5 hit points
lsr
sta BowserMovementSpeed ;set default movement speed here
rts
;--------------------------------
DuplicateEnemyObj:
ldy #$ff ;start at beginning of enemy slots
FSLoop: iny ;increment one slot
lda Enemy_Flag,y ;check enemy buffer flag for empty slot
bne FSLoop ;if set, branch and keep checking
sty DuplicateObj_Offset ;otherwise set offset here
txa ;transfer original enemy buffer offset
ora #%10000000 ;store with d7 set as flag in new enemy
sta Enemy_Flag,y ;slot as well as enemy offset
lda Enemy_PageLoc,x
sta Enemy_PageLoc,y ;copy page location and horizontal coordinates
lda Enemy_X_Position,x ;from original enemy to new enemy
sta Enemy_X_Position,y
lda #$01
sta Enemy_Flag,x ;set flag as normal for original enemy
sta Enemy_Y_HighPos,y ;set high vertical byte for new enemy
lda Enemy_Y_Position,x
sta Enemy_Y_Position,y ;copy vertical coordinate from original to new
FlmEx: rts ;and then leave
;--------------------------------
FlameYPosData:
.db $90, $80, $70, $90
FlameYMFAdderData:
.db $ff, $01
InitBowserFlame:
lda FrenzyEnemyTimer ;if timer not expired yet, branch to leave
bne FlmEx
sta Enemy_Y_MoveForce,x ;reset something here
lda NoiseSoundQueue
ora #Sfx_BowserFlame ;load bowser's flame sound into queue
sta NoiseSoundQueue
ldy BowserFront_Offset ;get bowser's buffer offset
lda Enemy_ID,y ;check for bowser
cmp #Bowser
beq SpawnFromMouth ;branch if found
jsr SetFlameTimer ;get timer data based on flame counter
clc
adc #$20 ;add 32 frames by default
ldy SecondaryHardMode
beq SetFrT ;if secondary mode flag not set, use as timer setting
sec
sbc #$10 ;otherwise subtract 16 frames for secondary hard mode
SetFrT: sta FrenzyEnemyTimer ;set timer accordingly
lda PseudoRandomBitReg,x
and #%00000011 ;get 2 LSB from first part of LSFR
sta BowserFlamePRandomOfs,x ;set here
tay ;use as offset
lda FlameYPosData,y ;load vertical position based on pseudorandom offset
PutAtRightExtent:
sta Enemy_Y_Position,x ;set vertical position
lda ScreenRight_X_Pos
clc
adc #$20 ;place enemy 32 pixels beyond right side of screen
sta Enemy_X_Position,x
lda ScreenRight_PageLoc
adc #$00 ;add carry
sta Enemy_PageLoc,x
jmp FinishFlame ;skip this part to finish setting values
SpawnFromMouth:
lda Enemy_X_Position,y ;get bowser's horizontal position
sec
sbc #$0e ;subtract 14 pixels
sta Enemy_X_Position,x ;save as flame's horizontal position
lda Enemy_PageLoc,y
sta Enemy_PageLoc,x ;copy page location from bowser to flame
lda Enemy_Y_Position,y
clc ;add 8 pixels to bowser's vertical position
adc #$08
sta Enemy_Y_Position,x ;save as flame's vertical position
lda PseudoRandomBitReg,x
and #%00000011 ;get 2 LSB from first part of LSFR
sta Enemy_YMF_Dummy,x ;save here
tay ;use as offset
lda FlameYPosData,y ;get value here using bits as offset
ldy #$00 ;load default offset
cmp Enemy_Y_Position,x ;compare value to flame's current vertical position
bcc SetMF ;if less, do not increment offset
iny ;otherwise increment now
SetMF: lda FlameYMFAdderData,y ;get value here and save
sta Enemy_Y_MoveForce,x ;to vertical movement force
lda #$00
sta EnemyFrenzyBuffer ;clear enemy frenzy buffer
FinishFlame:
lda #$08 ;set $08 for bounding box control
sta Enemy_BoundBoxCtrl,x
lda #$01 ;set high byte of vertical and
sta Enemy_Y_HighPos,x ;enemy buffer flag
sta Enemy_Flag,x
lsr
sta Enemy_X_MoveForce,x ;initialize horizontal movement force, and
sta Enemy_State,x ;enemy state
rts
;--------------------------------
FireworksXPosData:
.db $00, $30, $60, $60, $00, $20
FireworksYPosData:
.db $60, $40, $70, $40, $60, $30
InitFireworks:
lda FrenzyEnemyTimer ;if timer not expired yet, branch to leave
bne ExitFWk
lda #$20 ;otherwise reset timer
sta FrenzyEnemyTimer
dec FireworksCounter ;decrement for each explosion
ldy #$06 ;start at last slot
StarFChk: dey
lda Enemy_ID,y ;check for presence of star flag object
cmp #StarFlagObject ;if there isn't a star flag object,
bne StarFChk ;routine goes into infinite loop = crash
lda Enemy_X_Position,y
sec ;get horizontal coordinate of star flag object, then
sbc #$30 ;subtract 48 pixels from it and save to
pha ;the stack
lda Enemy_PageLoc,y
sbc #$00 ;subtract the carry from the page location
sta $00 ;of the star flag object
lda FireworksCounter ;get fireworks counter
clc
adc Enemy_State,y ;add state of star flag object (possibly not necessary)
tay ;use as offset
pla ;get saved horizontal coordinate of star flag - 48 pixels
clc
adc FireworksXPosData,y ;add number based on offset of fireworks counter
sta Enemy_X_Position,x ;store as the fireworks object horizontal coordinate
lda $00
adc #$00 ;add carry and store as page location for
sta Enemy_PageLoc,x ;the fireworks object
lda FireworksYPosData,y ;get vertical position using same offset
sta Enemy_Y_Position,x ;and store as vertical coordinate for fireworks object
lda #$01
sta Enemy_Y_HighPos,x ;store in vertical high byte
sta Enemy_Flag,x ;and activate enemy buffer flag
lsr
sta ExplosionGfxCounter,x ;initialize explosion counter
lda #$08
sta ExplosionTimerCounter,x ;set explosion timing counter
ExitFWk: rts
;--------------------------------
Bitmasks:
.db %00000001, %00000010, %00000100, %00001000, %00010000, %00100000, %01000000, %10000000
Enemy17YPosData:
.db $40, $30, $90, $50, $20, $60, $a0, $70
SwimCC_IDData:
.db $0a, $0b
BulletBillCheepCheep:
lda FrenzyEnemyTimer ;if timer not expired yet, branch to leave
bne ExF17
lda AreaType ;are we in a water-type level?
bne DoBulletBills ;if not, branch elsewhere
cpx #$03 ;are we past third enemy slot?
bcs ExF17 ;if so, branch to leave
ldy #$00 ;load default offset
lda PseudoRandomBitReg,x
cmp #$aa ;check first part of LSFR against preset value
bcc ChkW2 ;if less than preset, do not increment offset
iny ;otherwise increment
ChkW2: lda WorldNumber ;check world number
cmp #World2
beq Get17ID ;if we're on world 2, do not increment offset
iny ;otherwise increment
Get17ID: tya
and #%00000001 ;mask out all but last bit of offset
tay
lda SwimCC_IDData,y ;load identifier for cheep-cheeps
Set17ID: sta Enemy_ID,x ;store whatever's in A as enemy identifier
lda BitMFilter
cmp #$ff ;if not all bits set, skip init part and compare bits
bne GetRBit
lda #$00 ;initialize vertical position filter
sta BitMFilter
GetRBit: lda PseudoRandomBitReg,x ;get first part of LSFR
and #%00000111 ;mask out all but 3 LSB
ChkRBit: tay ;use as offset
lda Bitmasks,y ;load bitmask
bit BitMFilter ;perform AND on filter without changing it
beq AddFBit
iny ;increment offset
tya
and #%00000111 ;mask out all but 3 LSB thus keeping it 0-7
jmp ChkRBit ;do another check
AddFBit: ora BitMFilter ;add bit to already set bits in filter
sta BitMFilter ;and store
lda Enemy17YPosData,y ;load vertical position using offset
jsr PutAtRightExtent ;set vertical position and other values
sta Enemy_YMF_Dummy,x ;initialize dummy variable
lda #$20 ;set timer
sta FrenzyEnemyTimer
jmp CheckpointEnemyID ;process our new enemy object
DoBulletBills:
ldy #$ff ;start at beginning of enemy slots
BB_SLoop: iny ;move onto the next slot
cpy #$05 ;branch to play sound if we've done all slots
bcs FireBulletBill
lda Enemy_Flag,y ;if enemy buffer flag not set,
beq BB_SLoop ;loop back and check another slot
lda Enemy_ID,y
cmp #BulletBill_FrenzyVar ;check enemy identifier for
bne BB_SLoop ;bullet bill object (frenzy variant)
ExF17: rts ;if found, leave
FireBulletBill:
lda Square2SoundQueue
ora #Sfx_Blast ;play fireworks/gunfire sound
sta Square2SoundQueue
lda #BulletBill_FrenzyVar ;load identifier for bullet bill object
bne Set17ID ;unconditional branch
;--------------------------------
;$00 - used to store Y position of group enemies
;$01 - used to store enemy ID
;$02 - used to store page location of right side of screen
;$03 - used to store X position of right side of screen
HandleGroupEnemies:
ldy #$00 ;load value for green koopa troopa
sec
sbc #$37 ;subtract $37 from second byte read
pha ;save result in stack for now
cmp #$04 ;was byte in $3b-$3e range?
bcs SnglID ;if so, branch
pha ;save another copy to stack
ldy #Goomba ;load value for goomba enemy
lda PrimaryHardMode ;if primary hard mode flag not set,
beq PullID ;branch, otherwise change to value
ldy #BuzzyBeetle ;for buzzy beetle
PullID: pla ;get second copy from stack
SnglID: sty $01 ;save enemy id here
ldy #$b0 ;load default y coordinate
and #$02 ;check to see if d1 was set
beq SetYGp ;if so, move y coordinate up,
ldy #$70 ;otherwise branch and use default
SetYGp: sty $00 ;save y coordinate here
lda ScreenRight_PageLoc ;get page number of right edge of screen
sta $02 ;save here
lda ScreenRight_X_Pos ;get pixel coordinate of right edge
sta $03 ;save here
ldy #$02 ;load two enemies by default
pla ;get first copy from stack
lsr ;check to see if d0 was set
bcc CntGrp ;if not, use default value
iny ;otherwise increment to three enemies
CntGrp: sty NumberofGroupEnemies ;save number of enemies here
GrLoop: ldx #$ff ;start at beginning of enemy buffers
GSltLp: inx ;increment and branch if past
cpx #$05 ;end of buffers
bcs NextED
lda Enemy_Flag,x ;check to see if enemy is already
bne GSltLp ;stored in buffer, and branch if so
lda $01
sta Enemy_ID,x ;store enemy object identifier
lda $02
sta Enemy_PageLoc,x ;store page location for enemy object
lda $03
sta Enemy_X_Position,x ;store x coordinate for enemy object
clc
adc #$18 ;add 24 pixels for next enemy
sta $03
lda $02 ;add carry to page location for
adc #$00 ;next enemy
sta $02
lda $00 ;store y coordinate for enemy object
sta Enemy_Y_Position,x
lda #$01 ;activate flag for buffer, and
sta Enemy_Y_HighPos,x ;put enemy within the screen vertically
sta Enemy_Flag,x
jsr CheckpointEnemyID ;process each enemy object separately
dec NumberofGroupEnemies ;do this until we run out of enemy objects
bne GrLoop
NextED: jmp Inc2B ;jump to increment data offset and leave
;--------------------------------
InitPiranhaPlant:
lda #$01 ;set initial speed
sta PiranhaPlant_Y_Speed,x
lsr
sta Enemy_State,x ;initialize enemy state and what would normally
sta PiranhaPlant_MoveFlag,x ;be used as vertical speed, but not in this case
lda Enemy_Y_Position,x
sta PiranhaPlantDownYPos,x ;save original vertical coordinate here
sec
sbc #$18
sta PiranhaPlantUpYPos,x ;save original vertical coordinate - 24 pixels here
lda #$09
jmp SetBBox2 ;set specific value for bounding box control
;--------------------------------
InitEnemyFrenzy:
lda Enemy_ID,x ;load enemy identifier
sta EnemyFrenzyBuffer ;save in enemy frenzy buffer
sec
sbc #$12 ;subtract 12 and use as offset for jump engine
jsr JumpEngine
;frenzy object jump table
.dw LakituAndSpinyHandler
.dw NoFrenzyCode
.dw InitFlyingCheepCheep
.dw InitBowserFlame
.dw InitFireworks
.dw BulletBillCheepCheep
;--------------------------------
NoFrenzyCode:
rts
;--------------------------------
EndFrenzy:
ldy #$05 ;start at last slot
LakituChk: lda Enemy_ID,y ;check enemy identifiers
cmp #Lakitu ;for lakitu
bne NextFSlot
lda #$01 ;if found, set state
sta Enemy_State,y
NextFSlot: dey ;move onto the next slot
bpl LakituChk ;do this until all slots are checked
lda #$00
sta EnemyFrenzyBuffer ;empty enemy frenzy buffer
sta Enemy_Flag,x ;disable enemy buffer flag for this object
rts
;--------------------------------
InitJumpGPTroopa:
lda #$02 ;set for movement to the left
sta Enemy_MovingDir,x
lda #$f8 ;set horizontal speed
sta Enemy_X_Speed,x
TallBBox2: lda #$03 ;set specific value for bounding box control
SetBBox2: sta Enemy_BoundBoxCtrl,x ;set bounding box control then leave
rts
;--------------------------------
InitBalPlatform:
dec Enemy_Y_Position,x ;raise vertical position by two pixels
dec Enemy_Y_Position,x
ldy SecondaryHardMode ;if secondary hard mode flag not set,
bne AlignP ;branch ahead
ldy #$02 ;otherwise set value here
jsr PosPlatform ;do a sub to add or subtract pixels
AlignP: ldy #$ff ;set default value here for now
lda BalPlatformAlignment ;get current balance platform alignment
sta Enemy_State,x ;set platform alignment to object state here
bpl SetBPA ;if old alignment $ff, put $ff as alignment for negative
txa ;if old contents already $ff, put
tay ;object offset as alignment to make next positive
SetBPA: sty BalPlatformAlignment ;store whatever value's in Y here
lda #$00
sta Enemy_MovingDir,x ;init moving direction
tay ;init Y
jsr PosPlatform ;do a sub to add 8 pixels, then run shared code here
;--------------------------------
InitDropPlatform:
lda #$ff
sta PlatformCollisionFlag,x ;set some value here
jmp CommonPlatCode ;then jump ahead to execute more code
;--------------------------------
InitHoriPlatform:
lda #$00
sta XMoveSecondaryCounter,x ;init one of the moving counters
jmp CommonPlatCode ;jump ahead to execute more code
;--------------------------------
InitVertPlatform:
ldy #$40 ;set default value here
lda Enemy_Y_Position,x ;check vertical position
bpl SetYO ;if above a certain point, skip this part
eor #$ff
clc ;otherwise get two's compliment
adc #$01
ldy #$c0 ;get alternate value to add to vertical position
SetYO: sta YPlatformTopYPos,x ;save as top vertical position
tya
clc ;load value from earlier, add number of pixels
adc Enemy_Y_Position,x ;to vertical position
sta YPlatformCenterYPos,x ;save result as central vertical position
;--------------------------------
CommonPlatCode:
jsr InitVStf ;do a sub to init certain other values
SPBBox: lda #$05 ;set default bounding box size control
ldy AreaType
cpy #$03 ;check for castle-type level
beq CasPBB ;use default value if found
ldy SecondaryHardMode ;otherwise check for secondary hard mode flag
bne CasPBB ;if set, use default value
lda #$06 ;use alternate value if not castle or secondary not set
CasPBB: sta Enemy_BoundBoxCtrl,x ;set bounding box size control here and leave
rts
;--------------------------------
LargeLiftUp:
jsr PlatLiftUp ;execute code for platforms going up
jmp LargeLiftBBox ;overwrite bounding box for large platforms
LargeLiftDown:
jsr PlatLiftDown ;execute code for platforms going down
LargeLiftBBox:
jmp SPBBox ;jump to overwrite bounding box size control
;--------------------------------
PlatLiftUp:
lda #$10 ;set movement amount here
sta Enemy_Y_MoveForce,x
lda #$ff ;set moving speed for platforms going up
sta Enemy_Y_Speed,x
jmp CommonSmallLift ;skip ahead to part we should be executing
;--------------------------------
PlatLiftDown:
lda #$f0 ;set movement amount here
sta Enemy_Y_MoveForce,x
lda #$00 ;set moving speed for platforms going down
sta Enemy_Y_Speed,x
;--------------------------------
CommonSmallLift:
ldy #$01
jsr PosPlatform ;do a sub to add 12 pixels due to preset value
lda #$04
sta Enemy_BoundBoxCtrl,x ;set bounding box control for small platforms
rts
;--------------------------------
PlatPosDataLow:
.db $08,$0c,$f8
PlatPosDataHigh:
.db $00,$00,$ff
PosPlatform:
lda Enemy_X_Position,x ;get horizontal coordinate
clc
adc PlatPosDataLow,y ;add or subtract pixels depending on offset
sta Enemy_X_Position,x ;store as new horizontal coordinate
lda Enemy_PageLoc,x
adc PlatPosDataHigh,y ;add or subtract page location depending on offset
sta Enemy_PageLoc,x ;store as new page location
rts ;and go back
;--------------------------------
EndOfEnemyInitCode:
rts
;-------------------------------------------------------------------------------------
RunEnemyObjectsCore:
ldx ObjectOffset ;get offset for enemy object buffer
lda #$00 ;load value 0 for jump engine by default
ldy Enemy_ID,x
cpy #$15 ;if enemy object < $15, use default value
bcc JmpEO
tya ;otherwise subtract $14 from the value and use
sbc #$14 ;as value for jump engine
JmpEO: jsr JumpEngine
.dw RunNormalEnemies ;for objects $00-$14
.dw RunBowserFlame ;for objects $15-$1f
.dw RunFireworks
.dw NoRunCode
.dw NoRunCode
.dw NoRunCode
.dw NoRunCode
.dw RunFirebarObj
.dw RunFirebarObj
.dw RunFirebarObj
.dw RunFirebarObj
.dw RunFirebarObj
.dw RunFirebarObj ;for objects $20-$2f
.dw RunFirebarObj
.dw RunFirebarObj
.dw NoRunCode
.dw RunLargePlatform
.dw RunLargePlatform
.dw RunLargePlatform
.dw RunLargePlatform
.dw RunLargePlatform
.dw RunLargePlatform
.dw RunLargePlatform
.dw RunSmallPlatform
.dw RunSmallPlatform
.dw RunBowser
.dw PowerUpObjHandler
.dw VineObjectHandler
.dw NoRunCode ;for objects $30-$35
.dw RunStarFlagObj
.dw JumpspringHandler
.dw NoRunCode
.dw WarpZoneObject
.dw RunRetainerObj
;--------------------------------
NoRunCode:
rts
;--------------------------------
RunRetainerObj:
jsr GetEnemyOffscreenBits
jsr RelativeEnemyPosition
jmp EnemyGfxHandler
;--------------------------------
RunNormalEnemies:
lda #$00 ;init sprite attributes
sta Enemy_SprAttrib,x
jsr GetEnemyOffscreenBits
jsr RelativeEnemyPosition
jsr EnemyGfxHandler
jsr GetEnemyBoundBox
jsr EnemyToBGCollisionDet
jsr EnemiesCollision
jsr PlayerEnemyCollision
ldy TimerControl ;if master timer control set, skip to last routine
bne SkipMove
jsr EnemyMovementSubs
SkipMove: jmp OffscreenBoundsCheck
EnemyMovementSubs:
lda Enemy_ID,x
jsr JumpEngine
.dw MoveNormalEnemy ;only objects $00-$14 use this table
.dw MoveNormalEnemy
.dw MoveNormalEnemy
.dw MoveNormalEnemy
.dw MoveNormalEnemy
.dw ProcHammerBro
.dw MoveNormalEnemy
.dw MoveBloober
.dw MoveBulletBill
.dw NoMoveCode
.dw MoveSwimmingCheepCheep
.dw MoveSwimmingCheepCheep
.dw MovePodoboo
.dw MovePiranhaPlant
.dw MoveJumpingEnemy
.dw ProcMoveRedPTroopa
.dw MoveFlyGreenPTroopa
.dw MoveLakitu
.dw MoveNormalEnemy
.dw NoMoveCode ;dummy
.dw MoveFlyingCheepCheep
;--------------------------------
NoMoveCode:
rts
;--------------------------------
RunBowserFlame:
jsr ProcBowserFlame
jsr GetEnemyOffscreenBits
jsr RelativeEnemyPosition
jsr GetEnemyBoundBox
jsr PlayerEnemyCollision
jmp OffscreenBoundsCheck
;--------------------------------
RunFirebarObj:
jsr ProcFirebar
jmp OffscreenBoundsCheck
;--------------------------------
RunSmallPlatform:
jsr GetEnemyOffscreenBits
jsr RelativeEnemyPosition
jsr SmallPlatformBoundBox
jsr SmallPlatformCollision
jsr RelativeEnemyPosition
jsr DrawSmallPlatform
jsr MoveSmallPlatform
jmp OffscreenBoundsCheck
;--------------------------------
RunLargePlatform:
jsr GetEnemyOffscreenBits
jsr RelativeEnemyPosition
jsr LargePlatformBoundBox
jsr LargePlatformCollision
lda TimerControl ;if master timer control set,
bne SkipPT ;skip subroutine tree
jsr LargePlatformSubroutines
SkipPT: jsr RelativeEnemyPosition
jsr DrawLargePlatform
jmp OffscreenBoundsCheck
;--------------------------------
LargePlatformSubroutines:
lda Enemy_ID,x ;subtract $24 to get proper offset for jump table
sec
sbc #$24
jsr JumpEngine
.dw BalancePlatform ;table used by objects $24-$2a
.dw YMovingPlatform
.dw MoveLargeLiftPlat
.dw MoveLargeLiftPlat
.dw XMovingPlatform
.dw DropPlatform
.dw RightPlatform
;-------------------------------------------------------------------------------------
EraseEnemyObject:
lda #$00 ;clear all enemy object variables
sta Enemy_Flag,x
sta Enemy_ID,x
sta Enemy_State,x
sta FloateyNum_Control,x
sta EnemyIntervalTimer,x
sta ShellChainCounter,x
sta Enemy_SprAttrib,x
sta EnemyFrameTimer,x
rts
;-------------------------------------------------------------------------------------
MovePodoboo:
lda EnemyIntervalTimer,x ;check enemy timer
bne PdbM ;branch to move enemy if not expired
jsr InitPodoboo ;otherwise set up podoboo again
lda PseudoRandomBitReg+1,x ;get part of LSFR
ora #%10000000 ;set d7
sta Enemy_Y_MoveForce,x ;store as movement force
and #%00001111 ;mask out high nybble
ora #$06 ;set for at least six intervals
sta EnemyIntervalTimer,x ;store as new enemy timer
lda #$f9
sta Enemy_Y_Speed,x ;set vertical speed to move podoboo upwards
PdbM: jmp MoveJ_EnemyVertically ;branch to impose gravity on podoboo
;--------------------------------
;$00 - used in HammerBroJumpCode as bitmask
HammerThrowTmrData:
.db $30, $1c
XSpeedAdderData:
.db $00, $e8, $00, $18
RevivedXSpeed:
.db $08, $f8, $0c, $f4
ProcHammerBro:
lda Enemy_State,x ;check hammer bro's enemy state for d5 set
and #%00100000
beq ChkJH ;if not set, go ahead with code
jmp MoveDefeatedEnemy ;otherwise jump to something else
ChkJH: lda HammerBroJumpTimer,x ;check jump timer
beq HammerBroJumpCode ;if expired, branch to jump
dec HammerBroJumpTimer,x ;otherwise decrement jump timer
lda Enemy_OffscreenBits
and #%00001100 ;check offscreen bits
bne MoveHammerBroXDir ;if hammer bro a little offscreen, skip to movement code
lda HammerThrowingTimer,x ;check hammer throwing timer
bne DecHT ;if not expired, skip ahead, do not throw hammer
ldy SecondaryHardMode ;otherwise get secondary hard mode flag
lda HammerThrowTmrData,y ;get timer data using flag as offset
sta HammerThrowingTimer,x ;set as new timer
jsr SpawnHammerObj ;do a sub here to spawn hammer object
bcc DecHT ;if carry clear, hammer not spawned, skip to decrement timer
lda Enemy_State,x
ora #%00001000 ;set d3 in enemy state for hammer throw
sta Enemy_State,x
jmp MoveHammerBroXDir ;jump to move hammer bro
DecHT: dec HammerThrowingTimer,x ;decrement timer
jmp MoveHammerBroXDir ;jump to move hammer bro
HammerBroJumpLData:
.db $20, $37
HammerBroJumpCode:
lda Enemy_State,x ;get hammer bro's enemy state
and #%00000111 ;mask out all but 3 LSB
cmp #$01 ;check for d0 set (for jumping)
beq MoveHammerBroXDir ;if set, branch ahead to moving code
lda #$00 ;load default value here
sta $00 ;save into temp variable for now
ldy #$fa ;set default vertical speed
lda Enemy_Y_Position,x ;check hammer bro's vertical coordinate
bmi SetHJ ;if on the bottom half of the screen, use current speed
ldy #$fd ;otherwise set alternate vertical speed
cmp #$70 ;check to see if hammer bro is above the middle of screen
inc $00 ;increment preset value to $01
bcc SetHJ ;if above the middle of the screen, use current speed and $01
dec $00 ;otherwise return value to $00
lda PseudoRandomBitReg+1,x ;get part of LSFR, mask out all but LSB
and #$01
bne SetHJ ;if d0 of LSFR set, branch and use current speed and $00
ldy #$fa ;otherwise reset to default vertical speed
SetHJ: sty Enemy_Y_Speed,x ;set vertical speed for jumping
lda Enemy_State,x ;set d0 in enemy state for jumping
ora #$01
sta Enemy_State,x
lda $00 ;load preset value here to use as bitmask
and PseudoRandomBitReg+2,x ;and do bit-wise comparison with part of LSFR
tay ;then use as offset
lda SecondaryHardMode ;check secondary hard mode flag
bne HJump
tay ;if secondary hard mode flag clear, set offset to 0
HJump: lda HammerBroJumpLData,y ;get jump length timer data using offset from before
sta EnemyFrameTimer,x ;save in enemy timer
lda PseudoRandomBitReg+1,x
ora #%11000000 ;get contents of part of LSFR, set d7 and d6, then
sta HammerBroJumpTimer,x ;store in jump timer
MoveHammerBroXDir:
ldy #$fc ;move hammer bro a little to the left
lda FrameCounter
and #%01000000 ;change hammer bro's direction every 64 frames
bne Shimmy
ldy #$04 ;if d6 set in counter, move him a little to the right
Shimmy: sty Enemy_X_Speed,x ;store horizontal speed
ldy #$01 ;set to face right by default
jsr PlayerEnemyDiff ;get horizontal difference between player and hammer bro
bmi SetShim ;if enemy to the left of player, skip this part
iny ;set to face left
lda EnemyIntervalTimer,x ;check walking timer
bne SetShim ;if not yet expired, skip to set moving direction
lda #$f8
sta Enemy_X_Speed,x ;otherwise, make the hammer bro walk left towards player
SetShim: sty Enemy_MovingDir,x ;set moving direction
MoveNormalEnemy:
ldy #$00 ;init Y to leave horizontal movement as-is
lda Enemy_State,x
and #%01000000 ;check enemy state for d6 set, if set skip
bne FallE ;to move enemy vertically, then horizontally if necessary
lda Enemy_State,x
asl ;check enemy state for d7 set
bcs SteadM ;if set, branch to move enemy horizontally
lda Enemy_State,x
and #%00100000 ;check enemy state for d5 set
bne MoveDefeatedEnemy ;if set, branch to move defeated enemy object
lda Enemy_State,x
and #%00000111 ;check d2-d0 of enemy state for any set bits
beq SteadM ;if enemy in normal state, branch to move enemy horizontally
cmp #$05
beq FallE ;if enemy in state used by spiny's egg, go ahead here
cmp #$03
bcs ReviveStunned ;if enemy in states $03 or $04, skip ahead to yet another part
FallE: jsr MoveD_EnemyVertically ;do a sub here to move enemy downwards
ldy #$00
lda Enemy_State,x ;check for enemy state $02
cmp #$02
beq MEHor ;if found, branch to move enemy horizontally
and #%01000000 ;check for d6 set
beq SteadM ;if not set, branch to something else
lda Enemy_ID,x
cmp #PowerUpObject ;check for power-up object
beq SteadM
bne SlowM ;if any other object where d6 set, jump to set Y
MEHor: jmp MoveEnemyHorizontally ;jump here to move enemy horizontally for <> $2e and d6 set
SlowM: ldy #$01 ;if branched here, increment Y to slow horizontal movement
SteadM: lda Enemy_X_Speed,x ;get current horizontal speed
pha ;save to stack
bpl AddHS ;if not moving or moving right, skip, leave Y alone
iny
iny ;otherwise increment Y to next data
AddHS: clc
adc XSpeedAdderData,y ;add value here to slow enemy down if necessary
sta Enemy_X_Speed,x ;save as horizontal speed temporarily
jsr MoveEnemyHorizontally ;then do a sub to move horizontally
pla
sta Enemy_X_Speed,x ;get old horizontal speed from stack and return to
rts ;original memory location, then leave
ReviveStunned:
lda EnemyIntervalTimer,x ;if enemy timer not expired yet,
bne ChkKillGoomba ;skip ahead to something else
sta Enemy_State,x ;otherwise initialize enemy state to normal
lda FrameCounter
and #$01 ;get d0 of frame counter
tay ;use as Y and increment for movement direction
iny
sty Enemy_MovingDir,x ;store as pseudorandom movement direction
dey ;decrement for use as pointer
lda PrimaryHardMode ;check primary hard mode flag
beq SetRSpd ;if not set, use pointer as-is
iny
iny ;otherwise increment 2 bytes to next data
SetRSpd: lda RevivedXSpeed,y ;load and store new horizontal speed
sta Enemy_X_Speed,x ;and leave
rts
MoveDefeatedEnemy:
jsr MoveD_EnemyVertically ;execute sub to move defeated enemy downwards
jmp MoveEnemyHorizontally ;now move defeated enemy horizontally
ChkKillGoomba:
cmp #$0e ;check to see if enemy timer has reached
bne NKGmba ;a certain point, and branch to leave if not
lda Enemy_ID,x
cmp #Goomba ;check for goomba object
bne NKGmba ;branch if not found
jsr EraseEnemyObject ;otherwise, kill this goomba object
NKGmba: rts ;leave!
;--------------------------------
MoveJumpingEnemy:
jsr MoveJ_EnemyVertically ;do a sub to impose gravity on green paratroopa
jmp MoveEnemyHorizontally ;jump to move enemy horizontally
;--------------------------------
ProcMoveRedPTroopa:
lda Enemy_Y_Speed,x
ora Enemy_Y_MoveForce,x ;check for any vertical force or speed
bne MoveRedPTUpOrDown ;branch if any found
sta Enemy_YMF_Dummy,x ;initialize something here
lda Enemy_Y_Position,x ;check current vs. original vertical coordinate
cmp RedPTroopaOrigXPos,x
bcs MoveRedPTUpOrDown ;if current => original, skip ahead to more code
lda FrameCounter ;get frame counter
and #%00000111 ;mask out all but 3 LSB
bne NoIncPT ;if any bits set, branch to leave
inc Enemy_Y_Position,x ;otherwise increment red paratroopa's vertical position
NoIncPT: rts ;leave
MoveRedPTUpOrDown:
lda Enemy_Y_Position,x ;check current vs. central vertical coordinate
cmp RedPTroopaCenterYPos,x
bcc MovPTDwn ;if current < central, jump to move downwards
jmp MoveRedPTroopaUp ;otherwise jump to move upwards
MovPTDwn: jmp MoveRedPTroopaDown ;move downwards
;--------------------------------
;$00 - used to store adder for movement, also used as adder for platform
;$01 - used to store maximum value for secondary counter
MoveFlyGreenPTroopa:
jsr XMoveCntr_GreenPTroopa ;do sub to increment primary and secondary counters
jsr MoveWithXMCntrs ;do sub to move green paratroopa accordingly, and horizontally
ldy #$01 ;set Y to move green paratroopa down
lda FrameCounter
and #%00000011 ;check frame counter 2 LSB for any bits set
bne NoMGPT ;branch to leave if set to move up/down every fourth frame
lda FrameCounter
and #%01000000 ;check frame counter for d6 set
bne YSway ;branch to move green paratroopa down if set
ldy #$ff ;otherwise set Y to move green paratroopa up
YSway: sty $00 ;store adder here
lda Enemy_Y_Position,x
clc ;add or subtract from vertical position
adc $00 ;to give green paratroopa a wavy flight
sta Enemy_Y_Position,x
NoMGPT: rts ;leave!
XMoveCntr_GreenPTroopa:
lda #$13 ;load preset maximum value for secondary counter
XMoveCntr_Platform:
sta $01 ;store value here
lda FrameCounter
and #%00000011 ;branch to leave if not on
bne NoIncXM ;every fourth frame
ldy XMoveSecondaryCounter,x ;get secondary counter
lda XMovePrimaryCounter,x ;get primary counter
lsr
bcs DecSeXM ;if d0 of primary counter set, branch elsewhere
cpy $01 ;compare secondary counter to preset maximum value
beq IncPXM ;if equal, branch ahead of this part
inc XMoveSecondaryCounter,x ;increment secondary counter and leave
NoIncXM: rts
IncPXM: inc XMovePrimaryCounter,x ;increment primary counter and leave
rts
DecSeXM: tya ;put secondary counter in A
beq IncPXM ;if secondary counter at zero, branch back
dec XMoveSecondaryCounter,x ;otherwise decrement secondary counter and leave
rts
MoveWithXMCntrs:
lda XMoveSecondaryCounter,x ;save secondary counter to stack
pha
ldy #$01 ;set value here by default
lda XMovePrimaryCounter,x
and #%00000010 ;if d1 of primary counter is
bne XMRight ;set, branch ahead of this part here
lda XMoveSecondaryCounter,x
eor #$ff ;otherwise change secondary
clc ;counter to two's compliment
adc #$01
sta XMoveSecondaryCounter,x
ldy #$02 ;load alternate value here
XMRight: sty Enemy_MovingDir,x ;store as moving direction
jsr MoveEnemyHorizontally
sta $00 ;save value obtained from sub here
pla ;get secondary counter from stack
sta XMoveSecondaryCounter,x ;and return to original place
rts
;--------------------------------
BlooberBitmasks:
.db %00111111, %00000011
MoveBloober:
lda Enemy_State,x
and #%00100000 ;check enemy state for d5 set
bne MoveDefeatedBloober ;branch if set to move defeated bloober
ldy SecondaryHardMode ;use secondary hard mode flag as offset
lda PseudoRandomBitReg+1,x ;get LSFR
and BlooberBitmasks,y ;mask out bits in LSFR using bitmask loaded with offset
bne BlooberSwim ;if any bits set, skip ahead to make swim
txa
lsr ;check to see if on second or fourth slot (1 or 3)
bcc FBLeft ;if not, branch to figure out moving direction
ldy Player_MovingDir ;otherwise, load player's moving direction and
bcs SBMDir ;do an unconditional branch to set
FBLeft: ldy #$02 ;set left moving direction by default
jsr PlayerEnemyDiff ;get horizontal difference between player and bloober
bpl SBMDir ;if enemy to the right of player, keep left
dey ;otherwise decrement to set right moving direction
SBMDir: sty Enemy_MovingDir,x ;set moving direction of bloober, then continue on here
BlooberSwim:
jsr ProcSwimmingB ;execute sub to make bloober swim characteristically
lda Enemy_Y_Position,x ;get vertical coordinate
sec
sbc Enemy_Y_MoveForce,x ;subtract movement force
cmp #$20 ;check to see if position is above edge of status bar
bcc SwimX ;if so, don't do it
sta Enemy_Y_Position,x ;otherwise, set new vertical position, make bloober swim
SwimX: ldy Enemy_MovingDir,x ;check moving direction
dey
bne LeftSwim ;if moving to the left, branch to second part
lda Enemy_X_Position,x
clc ;add movement speed to horizontal coordinate
adc BlooperMoveSpeed,x
sta Enemy_X_Position,x ;store result as new horizontal coordinate
lda Enemy_PageLoc,x
adc #$00 ;add carry to page location
sta Enemy_PageLoc,x ;store as new page location and leave
rts
LeftSwim:
lda Enemy_X_Position,x
sec ;subtract movement speed from horizontal coordinate
sbc BlooperMoveSpeed,x
sta Enemy_X_Position,x ;store result as new horizontal coordinate
lda Enemy_PageLoc,x
sbc #$00 ;subtract borrow from page location
sta Enemy_PageLoc,x ;store as new page location and leave
rts
MoveDefeatedBloober:
jmp MoveEnemySlowVert ;jump to move defeated bloober downwards
ProcSwimmingB:
lda BlooperMoveCounter,x ;get enemy's movement counter
and #%00000010 ;check for d1 set
bne ChkForFloatdown ;branch if set
lda FrameCounter
and #%00000111 ;get 3 LSB of frame counter
pha ;and save it to the stack
lda BlooperMoveCounter,x ;get enemy's movement counter
lsr ;check for d0 set
bcs SlowSwim ;branch if set
pla ;pull 3 LSB of frame counter from the stack
bne BSwimE ;branch to leave, execute code only every eighth frame
lda Enemy_Y_MoveForce,x
clc ;add to movement force to speed up swim
adc #$01
sta Enemy_Y_MoveForce,x ;set movement force
sta BlooperMoveSpeed,x ;set as movement speed
cmp #$02
bne BSwimE ;if certain horizontal speed, branch to leave
inc BlooperMoveCounter,x ;otherwise increment movement counter
BSwimE: rts
SlowSwim:
pla ;pull 3 LSB of frame counter from the stack
bne NoSSw ;branch to leave, execute code only every eighth frame
lda Enemy_Y_MoveForce,x
sec ;subtract from movement force to slow swim
sbc #$01
sta Enemy_Y_MoveForce,x ;set movement force
sta BlooperMoveSpeed,x ;set as movement speed
bne NoSSw ;if any speed, branch to leave
inc BlooperMoveCounter,x ;otherwise increment movement counter
lda #$02
sta EnemyIntervalTimer,x ;set enemy's timer
NoSSw: rts ;leave
ChkForFloatdown:
lda EnemyIntervalTimer,x ;get enemy timer
beq ChkNearPlayer ;branch if expired
Floatdown:
lda FrameCounter ;get frame counter
lsr ;check for d0 set
bcs NoFD ;branch to leave on every other frame
inc Enemy_Y_Position,x ;otherwise increment vertical coordinate
NoFD: rts ;leave
ChkNearPlayer:
lda Enemy_Y_Position,x ;get vertical coordinate
adc #$10 ;add sixteen pixels
cmp Player_Y_Position ;compare result with player's vertical coordinate
bcc Floatdown ;if modified vertical less than player's, branch
lda #$00
sta BlooperMoveCounter,x ;otherwise nullify movement counter
rts
;--------------------------------
MoveBulletBill:
lda Enemy_State,x ;check bullet bill's enemy object state for d5 set
and #%00100000
beq NotDefB ;if not set, continue with movement code
jmp MoveJ_EnemyVertically ;otherwise jump to move defeated bullet bill downwards
NotDefB: lda #$e8 ;set bullet bill's horizontal speed
sta Enemy_X_Speed,x ;and move it accordingly (note: this bullet bill
jmp MoveEnemyHorizontally ;object occurs in frenzy object $17, not from cannons)
;--------------------------------
;$02 - used to hold preset values
;$03 - used to hold enemy state
SwimCCXMoveData:
.db $40, $80
.db $04, $04 ;residual data, not used
MoveSwimmingCheepCheep:
lda Enemy_State,x ;check cheep-cheep's enemy object state
and #%00100000 ;for d5 set
beq CCSwim ;if not set, continue with movement code
jmp MoveEnemySlowVert ;otherwise jump to move defeated cheep-cheep downwards
CCSwim: sta $03 ;save enemy state in $03
lda Enemy_ID,x ;get enemy identifier
sec
sbc #$0a ;subtract ten for cheep-cheep identifiers
tay ;use as offset
lda SwimCCXMoveData,y ;load value here
sta $02
lda Enemy_X_MoveForce,x ;load horizontal force
sec
sbc $02 ;subtract preset value from horizontal force
sta Enemy_X_MoveForce,x ;store as new horizontal force
lda Enemy_X_Position,x ;get horizontal coordinate
sbc #$00 ;subtract borrow (thus moving it slowly)
sta Enemy_X_Position,x ;and save as new horizontal coordinate
lda Enemy_PageLoc,x
sbc #$00 ;subtract borrow again, this time from the
sta Enemy_PageLoc,x ;page location, then save
lda #$20
sta $02 ;save new value here
cpx #$02 ;check enemy object offset
bcc ExSwCC ;if in first or second slot, branch to leave
lda CheepCheepMoveMFlag,x ;check movement flag
cmp #$10 ;if movement speed set to $00,
bcc CCSwimUpwards ;branch to move upwards
lda Enemy_YMF_Dummy,x
clc
adc $02 ;add preset value to dummy variable to get carry
sta Enemy_YMF_Dummy,x ;and save dummy
lda Enemy_Y_Position,x ;get vertical coordinate
adc $03 ;add carry to it plus enemy state to slowly move it downwards
sta Enemy_Y_Position,x ;save as new vertical coordinate
lda Enemy_Y_HighPos,x
adc #$00 ;add carry to page location and
jmp ChkSwimYPos ;jump to end of movement code
CCSwimUpwards:
lda Enemy_YMF_Dummy,x
sec
sbc $02 ;subtract preset value to dummy variable to get borrow
sta Enemy_YMF_Dummy,x ;and save dummy
lda Enemy_Y_Position,x ;get vertical coordinate
sbc $03 ;subtract borrow to it plus enemy state to slowly move it upwards
sta Enemy_Y_Position,x ;save as new vertical coordinate
lda Enemy_Y_HighPos,x
sbc #$00 ;subtract borrow from page location
ChkSwimYPos:
sta Enemy_Y_HighPos,x ;save new page location here
ldy #$00 ;load movement speed to upwards by default
lda Enemy_Y_Position,x ;get vertical coordinate
sec
sbc CheepCheepOrigYPos,x ;subtract original coordinate from current
bpl YPDiff ;if result positive, skip to next part
ldy #$10 ;otherwise load movement speed to downwards
eor #$ff
clc ;get two's compliment of result
adc #$01 ;to obtain total difference of original vs. current
YPDiff: cmp #$0f ;if difference between original vs. current vertical
bcc ExSwCC ;coordinates < 15 pixels, leave movement speed alone
tya
sta CheepCheepMoveMFlag,x ;otherwise change movement speed
ExSwCC: rts ;leave
;--------------------------------
;$00 - used as counter for firebar parts
;$01 - used for oscillated high byte of spin state or to hold horizontal adder
;$02 - used for oscillated high byte of spin state or to hold vertical adder
;$03 - used for mirror data
;$04 - used to store player's sprite 1 X coordinate
;$05 - used to evaluate mirror data
;$06 - used to store either screen X coordinate or sprite data offset
;$07 - used to store screen Y coordinate
;$ed - used to hold maximum length of firebar
;$ef - used to hold high byte of spinstate
;horizontal adder is at first byte + high byte of spinstate,
;vertical adder is same + 8 bytes, two's compliment
;if greater than $08 for proper oscillation
FirebarPosLookupTbl:
.db $00, $01, $03, $04, $05, $06, $07, $07, $08
.db $00, $03, $06, $09, $0b, $0d, $0e, $0f, $10
.db $00, $04, $09, $0d, $10, $13, $16, $17, $18
.db $00, $06, $0c, $12, $16, $1a, $1d, $1f, $20
.db $00, $07, $0f, $16, $1c, $21, $25, $27, $28
.db $00, $09, $12, $1b, $21, $27, $2c, $2f, $30
.db $00, $0b, $15, $1f, $27, $2e, $33, $37, $38
.db $00, $0c, $18, $24, $2d, $35, $3b, $3e, $40
.db $00, $0e, $1b, $28, $32, $3b, $42, $46, $48
.db $00, $0f, $1f, $2d, $38, $42, $4a, $4e, $50
.db $00, $11, $22, $31, $3e, $49, $51, $56, $58
FirebarMirrorData:
.db $01, $03, $02, $00
FirebarTblOffsets:
.db $00, $09, $12, $1b, $24, $2d
.db $36, $3f, $48, $51, $5a, $63
FirebarYPos:
.db $0c, $18
ProcFirebar:
jsr GetEnemyOffscreenBits ;get offscreen information
lda Enemy_OffscreenBits ;check for d3 set
and #%00001000 ;if so, branch to leave
bne SkipFBar
lda TimerControl ;if master timer control set, branch
bne SusFbar ;ahead of this part
lda FirebarSpinSpeed,x ;load spinning speed of firebar
jsr FirebarSpin ;modify current spinstate
and #%00011111 ;mask out all but 5 LSB
sta FirebarSpinState_High,x ;and store as new high byte of spinstate
SusFbar: lda FirebarSpinState_High,x ;get high byte of spinstate
ldy Enemy_ID,x ;check enemy identifier
cpy #$1f
bcc SetupGFB ;if < $1f (long firebar), branch
cmp #$08 ;check high byte of spinstate
beq SkpFSte ;if eight, branch to change
cmp #$18
bne SetupGFB ;if not at twenty-four branch to not change
SkpFSte: clc
adc #$01 ;add one to spinning thing to avoid horizontal state
sta FirebarSpinState_High,x
SetupGFB: sta $ef ;save high byte of spinning thing, modified or otherwise
jsr RelativeEnemyPosition ;get relative coordinates to screen
jsr GetFirebarPosition ;do a sub here (residual, too early to be used now)
ldy Enemy_SprDataOffset,x ;get OAM data offset
lda Enemy_Rel_YPos ;get relative vertical coordinate
sta Sprite_Y_Position,y ;store as Y in OAM data
sta $07 ;also save here
lda Enemy_Rel_XPos ;get relative horizontal coordinate
sta Sprite_X_Position,y ;store as X in OAM data
sta $06 ;also save here
lda #$01
sta $00 ;set $01 value here (not necessary)
jsr FirebarCollision ;draw fireball part and do collision detection
ldy #$05 ;load value for short firebars by default
lda Enemy_ID,x
cmp #$1f ;are we doing a long firebar?
bcc SetMFbar ;no, branch then
ldy #$0b ;otherwise load value for long firebars
SetMFbar: sty $ed ;store maximum value for length of firebars
lda #$00
sta $00 ;initialize counter here
DrawFbar: lda $ef ;load high byte of spinstate
jsr GetFirebarPosition ;get fireball position data depending on firebar part
jsr DrawFirebar_Collision ;position it properly, draw it and do collision detection
lda $00 ;check which firebar part
cmp #$04
bne NextFbar
ldy DuplicateObj_Offset ;if we arrive at fifth firebar part,
lda Enemy_SprDataOffset,y ;get offset from long firebar and load OAM data offset
sta $06 ;using long firebar offset, then store as new one here
NextFbar: inc $00 ;move onto the next firebar part
lda $00
cmp $ed ;if we end up at the maximum part, go on and leave
bcc DrawFbar ;otherwise go back and do another
SkipFBar: rts
DrawFirebar_Collision:
lda $03 ;store mirror data elsewhere
sta $05
ldy $06 ;load OAM data offset for firebar
lda $01 ;load horizontal adder we got from position loader
lsr $05 ;shift LSB of mirror data
bcs AddHA ;if carry was set, skip this part
eor #$ff
adc #$01 ;otherwise get two's compliment of horizontal adder
AddHA: clc ;add horizontal coordinate relative to screen to
adc Enemy_Rel_XPos ;horizontal adder, modified or otherwise
sta Sprite_X_Position,y ;store as X coordinate here
sta $06 ;store here for now, note offset is saved in Y still
cmp Enemy_Rel_XPos ;compare X coordinate of sprite to original X of firebar
bcs SubtR1 ;if sprite coordinate => original coordinate, branch
lda Enemy_Rel_XPos
sec ;otherwise subtract sprite X from the
sbc $06 ;original one and skip this part
jmp ChkFOfs
SubtR1: sec ;subtract original X from the
sbc Enemy_Rel_XPos ;current sprite X
ChkFOfs: cmp #$59 ;if difference of coordinates within a certain range,
bcc VAHandl ;continue by handling vertical adder
lda #$f8 ;otherwise, load offscreen Y coordinate
bne SetVFbr ;and unconditionally branch to move sprite offscreen
VAHandl: lda Enemy_Rel_YPos ;if vertical relative coordinate offscreen,
cmp #$f8 ;skip ahead of this part and write into sprite Y coordinate
beq SetVFbr
lda $02 ;load vertical adder we got from position loader
lsr $05 ;shift LSB of mirror data one more time
bcs AddVA ;if carry was set, skip this part
eor #$ff
adc #$01 ;otherwise get two's compliment of second part
AddVA: clc ;add vertical coordinate relative to screen to
adc Enemy_Rel_YPos ;the second data, modified or otherwise
SetVFbr: sta Sprite_Y_Position,y ;store as Y coordinate here
sta $07 ;also store here for now
FirebarCollision:
jsr DrawFirebar ;run sub here to draw current tile of firebar
tya ;return OAM data offset and save
pha ;to the stack for now
lda StarInvincibleTimer ;if star mario invincibility timer
ora TimerControl ;or master timer controls set
bne NoColFB ;then skip all of this
sta $05 ;otherwise initialize counter
ldy Player_Y_HighPos
dey ;if player's vertical high byte offscreen,
bne NoColFB ;skip all of this
ldy Player_Y_Position ;get player's vertical position
lda PlayerSize ;get player's size
bne AdjSm ;if player small, branch to alter variables
lda CrouchingFlag
beq BigJp ;if player big and not crouching, jump ahead
AdjSm: inc $05 ;if small or big but crouching, execute this part
inc $05 ;first increment our counter twice (setting $02 as flag)
tya
clc ;then add 24 pixels to the player's
adc #$18 ;vertical coordinate
tay
BigJp: tya ;get vertical coordinate, altered or otherwise, from Y
FBCLoop: sec ;subtract vertical position of firebar
sbc $07 ;from the vertical coordinate of the player
bpl ChkVFBD ;if player lower on the screen than firebar,
eor #$ff ;skip two's compliment part
clc ;otherwise get two's compliment
adc #$01
ChkVFBD: cmp #$08 ;if difference => 8 pixels, skip ahead of this part
bcs Chk2Ofs
lda $06 ;if firebar on far right on the screen, skip this,
cmp #$f0 ;because, really, what's the point?
bcs Chk2Ofs
lda Sprite_X_Position+4 ;get OAM X coordinate for sprite #1
clc
adc #$04 ;add four pixels
sta $04 ;store here
sec ;subtract horizontal coordinate of firebar
sbc $06 ;from the X coordinate of player's sprite 1
bpl ChkFBCl ;if modded X coordinate to the right of firebar
eor #$ff ;skip two's compliment part
clc ;otherwise get two's compliment
adc #$01
ChkFBCl: cmp #$08 ;if difference < 8 pixels, collision, thus branch
bcc ChgSDir ;to process
Chk2Ofs: lda $05 ;if value of $02 was set earlier for whatever reason,
cmp #$02 ;branch to increment OAM offset and leave, no collision
beq NoColFB
ldy $05 ;otherwise get temp here and use as offset
lda Player_Y_Position
clc
adc FirebarYPos,y ;add value loaded with offset to player's vertical coordinate
inc $05 ;then increment temp and jump back
jmp FBCLoop
ChgSDir: ldx #$01 ;set movement direction by default
lda $04 ;if OAM X coordinate of player's sprite 1
cmp $06 ;is greater than horizontal coordinate of firebar
bcs SetSDir ;then do not alter movement direction
inx ;otherwise increment it
SetSDir: stx Enemy_MovingDir ;store movement direction here
ldx #$00
lda $00 ;save value written to $00 to stack
pha
jsr InjurePlayer ;perform sub to hurt or kill player
pla
sta $00 ;get value of $00 from stack
NoColFB: pla ;get OAM data offset
clc ;add four to it and save
adc #$04
sta $06
ldx ObjectOffset ;get enemy object buffer offset and leave
rts
GetFirebarPosition:
pha ;save high byte of spinstate to the stack
and #%00001111 ;mask out low nybble
cmp #$09
bcc GetHAdder ;if lower than $09, branch ahead
eor #%00001111 ;otherwise get two's compliment to oscillate
clc
adc #$01
GetHAdder: sta $01 ;store result, modified or not, here
ldy $00 ;load number of firebar ball where we're at
lda FirebarTblOffsets,y ;load offset to firebar position data
clc
adc $01 ;add oscillated high byte of spinstate
tay ;to offset here and use as new offset
lda FirebarPosLookupTbl,y ;get data here and store as horizontal adder
sta $01
pla ;pull whatever was in A from the stack
pha ;save it again because we still need it
clc
adc #$08 ;add eight this time, to get vertical adder
and #%00001111 ;mask out high nybble
cmp #$09 ;if lower than $09, branch ahead
bcc GetVAdder
eor #%00001111 ;otherwise get two's compliment
clc
adc #$01
GetVAdder: sta $02 ;store result here
ldy $00
lda FirebarTblOffsets,y ;load offset to firebar position data again
clc
adc $02 ;this time add value in $02 to offset here and use as offset
tay
lda FirebarPosLookupTbl,y ;get data here and store as vertica adder
sta $02
pla ;pull out whatever was in A one last time
lsr ;divide by eight or shift three to the right
lsr
lsr
tay ;use as offset
lda FirebarMirrorData,y ;load mirroring data here
sta $03 ;store
rts
;--------------------------------
PRandomSubtracter:
.db $f8, $a0, $70, $bd, $00
FlyCCBPriority:
.db $20, $20, $20, $00, $00
MoveFlyingCheepCheep:
lda Enemy_State,x ;check cheep-cheep's enemy state
and #%00100000 ;for d5 set
beq FlyCC ;branch to continue code if not set
lda #$00
sta Enemy_SprAttrib,x ;otherwise clear sprite attributes
jmp MoveJ_EnemyVertically ;and jump to move defeated cheep-cheep downwards
FlyCC: jsr MoveEnemyHorizontally ;move cheep-cheep horizontally based on speed and force
ldy #$0d ;set vertical movement amount
lda #$05 ;set maximum speed
jsr SetXMoveAmt ;branch to impose gravity on flying cheep-cheep
lda Enemy_Y_MoveForce,x
lsr ;get vertical movement force and
lsr ;move high nybble to low
lsr
lsr
tay ;save as offset (note this tends to go into reach of code)
lda Enemy_Y_Position,x ;get vertical position
sec ;subtract pseudorandom value based on offset from position
sbc PRandomSubtracter,y
bpl AddCCF ;if result within top half of screen, skip this part
eor #$ff
clc ;otherwise get two's compliment
adc #$01
AddCCF: cmp #$08 ;if result or two's compliment greater than eight,
bcs BPGet ;skip to the end without changing movement force
lda Enemy_Y_MoveForce,x
clc
adc #$10 ;otherwise add to it
sta Enemy_Y_MoveForce,x
lsr ;move high nybble to low again
lsr
lsr
lsr
tay
BPGet: lda FlyCCBPriority,y ;load bg priority data and store (this is very likely
sta Enemy_SprAttrib,x ;broken or residual code, value is overwritten before
rts ;drawing it next frame), then leave
;--------------------------------
;$00 - used to hold horizontal difference
;$01-$03 - used to hold difference adjusters
LakituDiffAdj:
.db $15, $30, $40
MoveLakitu:
lda Enemy_State,x ;check lakitu's enemy state
and #%00100000 ;for d5 set
beq ChkLS ;if not set, continue with code
jmp MoveD_EnemyVertically ;otherwise jump to move defeated lakitu downwards
ChkLS: lda Enemy_State,x ;if lakitu's enemy state not set at all,
beq Fr12S ;go ahead and continue with code
lda #$00
sta LakituMoveDirection,x ;otherwise initialize moving direction to move to left
sta EnemyFrenzyBuffer ;initialize frenzy buffer
lda #$10
bne SetLSpd ;load horizontal speed and do unconditional branch
Fr12S: lda #Spiny
sta EnemyFrenzyBuffer ;set spiny identifier in frenzy buffer
ldy #$02
LdLDa: lda LakituDiffAdj,y ;load values
sta $0001,y ;store in zero page
dey
bpl LdLDa ;do this until all values are stired
jsr PlayerLakituDiff ;execute sub to set speed and create spinys
SetLSpd: sta LakituMoveSpeed,x ;set movement speed returned from sub
ldy #$01 ;set moving direction to right by default
lda LakituMoveDirection,x
and #$01 ;get LSB of moving direction
bne SetLMov ;if set, branch to the end to use moving direction
lda LakituMoveSpeed,x
eor #$ff ;get two's compliment of moving speed
clc
adc #$01
sta LakituMoveSpeed,x ;store as new moving speed
iny ;increment moving direction to left
SetLMov: sty Enemy_MovingDir,x ;store moving direction
jmp MoveEnemyHorizontally ;move lakitu horizontally
PlayerLakituDiff:
ldy #$00 ;set Y for default value
jsr PlayerEnemyDiff ;get horizontal difference between enemy and player
bpl ChkLakDif ;branch if enemy is to the right of the player
iny ;increment Y for left of player
lda $00
eor #$ff ;get two's compliment of low byte of horizontal difference
clc
adc #$01 ;store two's compliment as horizontal difference
sta $00
ChkLakDif: lda $00 ;get low byte of horizontal difference
cmp #$3c ;if within a certain distance of player, branch
bcc ChkPSpeed
lda #$3c ;otherwise set maximum distance
sta $00
lda Enemy_ID,x ;check if lakitu is in our current enemy slot
cmp #Lakitu
bne ChkPSpeed ;if not, branch elsewhere
tya ;compare contents of Y, now in A
cmp LakituMoveDirection,x ;to what is being used as horizontal movement direction
beq ChkPSpeed ;if moving toward the player, branch, do not alter
lda LakituMoveDirection,x ;if moving to the left beyond maximum distance,
beq SetLMovD ;branch and alter without delay
dec LakituMoveSpeed,x ;decrement horizontal speed
lda LakituMoveSpeed,x ;if horizontal speed not yet at zero, branch to leave
bne ExMoveLak
SetLMovD: tya ;set horizontal direction depending on horizontal
sta LakituMoveDirection,x ;difference between enemy and player if necessary
ChkPSpeed: lda $00
and #%00111100 ;mask out all but four bits in the middle
lsr ;divide masked difference by four
lsr
sta $00 ;store as new value
ldy #$00 ;init offset
lda Player_X_Speed
beq SubDifAdj ;if player not moving horizontally, branch
lda ScrollAmount
beq SubDifAdj ;if scroll speed not set, branch to same place
iny ;otherwise increment offset
lda Player_X_Speed
cmp #$19 ;if player not running, branch
bcc ChkSpinyO
lda ScrollAmount
cmp #$02 ;if scroll speed below a certain amount, branch
bcc ChkSpinyO ;to same place
iny ;otherwise increment once more
ChkSpinyO: lda Enemy_ID,x ;check for spiny object
cmp #Spiny
bne ChkEmySpd ;branch if not found
lda Player_X_Speed ;if player not moving, skip this part
bne SubDifAdj
ChkEmySpd: lda Enemy_Y_Speed,x ;check vertical speed
bne SubDifAdj ;branch if nonzero
ldy #$00 ;otherwise reinit offset
SubDifAdj: lda $0001,y ;get one of three saved values from earlier
ldy $00 ;get saved horizontal difference
SPixelLak: sec ;subtract one for each pixel of horizontal difference
sbc #$01 ;from one of three saved values
dey
bpl SPixelLak ;branch until all pixels are subtracted, to adjust difference
ExMoveLak: rts ;leave!!!
;-------------------------------------------------------------------------------------
;$04-$05 - used to store name table address in little endian order
BridgeCollapseData:
.db $1a ;axe
.db $58 ;chain
.db $98, $96, $94, $92, $90, $8e, $8c ;bridge
.db $8a, $88, $86, $84, $82, $80
BridgeCollapse:
ldx BowserFront_Offset ;get enemy offset for bowser
lda Enemy_ID,x ;check enemy object identifier for bowser
cmp #Bowser ;if not found, branch ahead,
bne SetM2 ;metatile removal not necessary
stx ObjectOffset ;store as enemy offset here
lda Enemy_State,x ;if bowser in normal state, skip all of this
beq RemoveBridge
and #%01000000 ;if bowser's state has d6 clear, skip to silence music
beq SetM2
lda Enemy_Y_Position,x ;check bowser's vertical coordinate
cmp #$e0 ;if bowser not yet low enough, skip this part ahead
bcc MoveD_Bowser
SetM2: lda #Silence ;silence music
sta EventMusicQueue
inc OperMode_Task ;move onto next secondary mode in autoctrl mode
jmp KillAllEnemies ;jump to empty all enemy slots and then leave
MoveD_Bowser:
jsr MoveEnemySlowVert ;do a sub to move bowser downwards
jmp BowserGfxHandler ;jump to draw bowser's front and rear, then leave
RemoveBridge:
dec BowserFeetCounter ;decrement timer to control bowser's feet
bne NoBFall ;if not expired, skip all of this
lda #$04
sta BowserFeetCounter ;otherwise, set timer now
lda BowserBodyControls
eor #$01 ;invert bit to control bowser's feet
sta BowserBodyControls
lda #$22 ;put high byte of name table address here for now
sta $05
ldy BridgeCollapseOffset ;get bridge collapse offset here
lda BridgeCollapseData,y ;load low byte of name table address and store here
sta $04
ldy VRAM_Buffer1_Offset ;increment vram buffer offset
iny
ldx #$0c ;set offset for tile data for sub to draw blank metatile
jsr RemBridge ;do sub here to remove bowser's bridge metatiles
ldx ObjectOffset ;get enemy offset
jsr MoveVOffset ;set new vram buffer offset
lda #Sfx_Blast ;load the fireworks/gunfire sound into the square 2 sfx
sta Square2SoundQueue ;queue while at the same time loading the brick
lda #Sfx_BrickShatter ;shatter sound into the noise sfx queue thus
sta NoiseSoundQueue ;producing the unique sound of the bridge collapsing
inc BridgeCollapseOffset ;increment bridge collapse offset
lda BridgeCollapseOffset
cmp #$0f ;if bridge collapse offset has not yet reached
bne NoBFall ;the end, go ahead and skip this part
jsr InitVStf ;initialize whatever vertical speed bowser has
lda #%01000000
sta Enemy_State,x ;set bowser's state to one of defeated states (d6 set)
lda #Sfx_BowserFall
sta Square2SoundQueue ;play bowser defeat sound
NoBFall: jmp BowserGfxHandler ;jump to code that draws bowser
;--------------------------------
PRandomRange:
.db $21, $41, $11, $31
RunBowser:
lda Enemy_State,x ;if d5 in enemy state is not set
and #%00100000 ;then branch elsewhere to run bowser
beq BowserControl
lda Enemy_Y_Position,x ;otherwise check vertical position
cmp #$e0 ;if above a certain point, branch to move defeated bowser
bcc MoveD_Bowser ;otherwise proceed to KillAllEnemies
KillAllEnemies:
ldx #$04 ;start with last enemy slot
KillLoop: jsr EraseEnemyObject ;branch to kill enemy objects
dex ;move onto next enemy slot
bpl KillLoop ;do this until all slots are emptied
sta EnemyFrenzyBuffer ;empty frenzy buffer
ldx ObjectOffset ;get enemy object offset and leave
rts
BowserControl:
lda #$00
sta EnemyFrenzyBuffer ;empty frenzy buffer
lda TimerControl ;if master timer control not set,
beq ChkMouth ;skip jump and execute code here
jmp SkipToFB ;otherwise, jump over a bunch of code
ChkMouth: lda BowserBodyControls ;check bowser's mouth
bpl FeetTmr ;if bit clear, go ahead with code here
jmp HammerChk ;otherwise skip a whole section starting here
FeetTmr: dec BowserFeetCounter ;decrement timer to control bowser's feet
bne ResetMDr ;if not expired, skip this part
lda #$20 ;otherwise, reset timer
sta BowserFeetCounter
lda BowserBodyControls ;and invert bit used
eor #%00000001 ;to control bowser's feet
sta BowserBodyControls
ResetMDr: lda FrameCounter ;check frame counter
and #%00001111 ;if not on every sixteenth frame, skip
bne B_FaceP ;ahead to continue code
lda #$02 ;otherwise reset moving/facing direction every
sta Enemy_MovingDir,x ;sixteen frames
B_FaceP: lda EnemyFrameTimer,x ;if timer set here expired,
beq GetPRCmp ;branch to next section
jsr PlayerEnemyDiff ;get horizontal difference between player and bowser,
bpl GetPRCmp ;and branch if bowser to the right of the player
lda #$01
sta Enemy_MovingDir,x ;set bowser to move and face to the right
lda #$02
sta BowserMovementSpeed ;set movement speed
lda #$20
sta EnemyFrameTimer,x ;set timer here
sta BowserFireBreathTimer ;set timer used for bowser's flame
lda Enemy_X_Position,x
cmp #$c8 ;if bowser to the right past a certain point,
bcs HammerChk ;skip ahead to some other section
GetPRCmp: lda FrameCounter ;get frame counter
and #%00000011
bne HammerChk ;execute this code every fourth frame, otherwise branch
lda Enemy_X_Position,x
cmp BowserOrigXPos ;if bowser not at original horizontal position,
bne GetDToO ;branch to skip this part
lda PseudoRandomBitReg,x
and #%00000011 ;get pseudorandom offset
tay
lda PRandomRange,y ;load value using pseudorandom offset
sta MaxRangeFromOrigin ;and store here
GetDToO: lda Enemy_X_Position,x
clc ;add movement speed to bowser's horizontal
adc BowserMovementSpeed ;coordinate and save as new horizontal position
sta Enemy_X_Position,x
ldy Enemy_MovingDir,x
cpy #$01 ;if bowser moving and facing to the right, skip ahead
beq HammerChk
ldy #$ff ;set default movement speed here (move left)
sec ;get difference of current vs. original
sbc BowserOrigXPos ;horizontal position
bpl CompDToO ;if current position to the right of original, skip ahead
eor #$ff
clc ;get two's compliment
adc #$01
ldy #$01 ;set alternate movement speed here (move right)
CompDToO: cmp MaxRangeFromOrigin ;compare difference with pseudorandom value
bcc HammerChk ;if difference < pseudorandom value, leave speed alone
sty BowserMovementSpeed ;otherwise change bowser's movement speed
HammerChk: lda EnemyFrameTimer,x ;if timer set here not expired yet, skip ahead to
bne MakeBJump ;some other section of code
jsr MoveEnemySlowVert ;otherwise start by moving bowser downwards
lda WorldNumber ;check world number
cmp #World6
bcc SetHmrTmr ;if world 1-5, skip this part (not time to throw hammers yet)
lda FrameCounter
and #%00000011 ;check to see if it's time to execute sub
bne SetHmrTmr ;if not, skip sub, otherwise
jsr SpawnHammerObj ;execute sub on every fourth frame to spawn misc object (hammer)
SetHmrTmr: lda Enemy_Y_Position,x ;get current vertical position
cmp #$80 ;if still above a certain point
bcc ChkFireB ;then skip to world number check for flames
lda PseudoRandomBitReg,x
and #%00000011 ;get pseudorandom offset
tay
lda PRandomRange,y ;get value using pseudorandom offset
sta EnemyFrameTimer,x ;set for timer here
SkipToFB: jmp ChkFireB ;jump to execute flames code
MakeBJump: cmp #$01 ;if timer not yet about to expire,
bne ChkFireB ;skip ahead to next part
dec Enemy_Y_Position,x ;otherwise decrement vertical coordinate
jsr InitVStf ;initialize movement amount
lda #$fe
sta Enemy_Y_Speed,x ;set vertical speed to move bowser upwards
ChkFireB: lda WorldNumber ;check world number here
cmp #World8 ;world 8?
beq SpawnFBr ;if so, execute this part here
cmp #World6 ;world 6-7?
bcs BowserGfxHandler ;if so, skip this part here
SpawnFBr: lda BowserFireBreathTimer ;check timer here
bne BowserGfxHandler ;if not expired yet, skip all of this
lda #$20
sta BowserFireBreathTimer ;set timer here
lda BowserBodyControls
eor #%10000000 ;invert bowser's mouth bit to open
sta BowserBodyControls ;and close bowser's mouth
bmi ChkFireB ;if bowser's mouth open, loop back
jsr SetFlameTimer ;get timing for bowser's flame
ldy SecondaryHardMode
beq SetFBTmr ;if secondary hard mode flag not set, skip this
sec
sbc #$10 ;otherwise subtract from value in A
SetFBTmr: sta BowserFireBreathTimer ;set value as timer here
lda #BowserFlame ;put bowser's flame identifier
sta EnemyFrenzyBuffer ;in enemy frenzy buffer
;--------------------------------
BowserGfxHandler:
jsr ProcessBowserHalf ;do a sub here to process bowser's front
ldy #$10 ;load default value here to position bowser's rear
lda Enemy_MovingDir,x ;check moving direction
lsr
bcc CopyFToR ;if moving left, use default
ldy #$f0 ;otherwise load alternate positioning value here
CopyFToR: tya ;move bowser's rear object position value to A
clc
adc Enemy_X_Position,x ;add to bowser's front object horizontal coordinate
ldy DuplicateObj_Offset ;get bowser's rear object offset
sta Enemy_X_Position,y ;store A as bowser's rear horizontal coordinate
lda Enemy_Y_Position,x
clc ;add eight pixels to bowser's front object
adc #$08 ;vertical coordinate and store as vertical coordinate
sta Enemy_Y_Position,y ;for bowser's rear
lda Enemy_State,x
sta Enemy_State,y ;copy enemy state directly from front to rear
lda Enemy_MovingDir,x
sta Enemy_MovingDir,y ;copy moving direction also
lda ObjectOffset ;save enemy object offset of front to stack
pha
ldx DuplicateObj_Offset ;put enemy object offset of rear as current
stx ObjectOffset
lda #Bowser ;set bowser's enemy identifier
sta Enemy_ID,x ;store in bowser's rear object
jsr ProcessBowserHalf ;do a sub here to process bowser's rear
pla
sta ObjectOffset ;get original enemy object offset
tax
lda #$00 ;nullify bowser's front/rear graphics flag
sta BowserGfxFlag
ExBGfxH: rts ;leave!
ProcessBowserHalf:
inc BowserGfxFlag ;increment bowser's graphics flag, then run subroutines
jsr RunRetainerObj ;to get offscreen bits, relative position and draw bowser (finally!)
lda Enemy_State,x
bne ExBGfxH ;if either enemy object not in normal state, branch to leave
lda #$0a
sta Enemy_BoundBoxCtrl,x ;set bounding box size control
jsr GetEnemyBoundBox ;get bounding box coordinates
jmp PlayerEnemyCollision ;do player-to-enemy collision detection
;-------------------------------------------------------------------------------------
;$00 - used to hold movement force and tile number
;$01 - used to hold sprite attribute data
FlameTimerData:
.db $bf, $40, $bf, $bf, $bf, $40, $40, $bf
SetFlameTimer:
ldy BowserFlameTimerCtrl ;load counter as offset
inc BowserFlameTimerCtrl ;increment
lda BowserFlameTimerCtrl ;mask out all but 3 LSB
and #%00000111 ;to keep in range of 0-7
sta BowserFlameTimerCtrl
lda FlameTimerData,y ;load value to be used then leave
ExFl: rts
ProcBowserFlame:
lda TimerControl ;if master timer control flag set,
bne SetGfxF ;skip all of this
lda #$40 ;load default movement force
ldy SecondaryHardMode
beq SFlmX ;if secondary hard mode flag not set, use default
lda #$60 ;otherwise load alternate movement force to go faster
SFlmX: sta $00 ;store value here
lda Enemy_X_MoveForce,x
sec ;subtract value from movement force
sbc $00
sta Enemy_X_MoveForce,x ;save new value
lda Enemy_X_Position,x
sbc #$01 ;subtract one from horizontal position to move
sta Enemy_X_Position,x ;to the left
lda Enemy_PageLoc,x
sbc #$00 ;subtract borrow from page location
sta Enemy_PageLoc,x
ldy BowserFlamePRandomOfs,x ;get some value here and use as offset
lda Enemy_Y_Position,x ;load vertical coordinate
cmp FlameYPosData,y ;compare against coordinate data using $0417,x as offset
beq SetGfxF ;if equal, branch and do not modify coordinate
clc
adc Enemy_Y_MoveForce,x ;otherwise add value here to coordinate and store
sta Enemy_Y_Position,x ;as new vertical coordinate
SetGfxF: jsr RelativeEnemyPosition ;get new relative coordinates
lda Enemy_State,x ;if bowser's flame not in normal state,
bne ExFl ;branch to leave
lda #$51 ;otherwise, continue
sta $00 ;write first tile number
ldy #$02 ;load attributes without vertical flip by default
lda FrameCounter
and #%00000010 ;invert vertical flip bit every 2 frames
beq FlmeAt ;if d1 not set, write default value
ldy #$82 ;otherwise write value with vertical flip bit set
FlmeAt: sty $01 ;set bowser's flame sprite attributes here
ldy Enemy_SprDataOffset,x ;get OAM data offset
ldx #$00
DrawFlameLoop:
lda Enemy_Rel_YPos ;get Y relative coordinate of current enemy object
sta Sprite_Y_Position,y ;write into Y coordinate of OAM data
lda $00
sta Sprite_Tilenumber,y ;write current tile number into OAM data
inc $00 ;increment tile number to draw more bowser's flame
lda $01
sta Sprite_Attributes,y ;write saved attributes into OAM data
lda Enemy_Rel_XPos
sta Sprite_X_Position,y ;write X relative coordinate of current enemy object
clc
adc #$08
sta Enemy_Rel_XPos ;then add eight to it and store
iny
iny
iny
iny ;increment Y four times to move onto the next OAM
inx ;move onto the next OAM, and branch if three
cpx #$03 ;have not yet been done
bcc DrawFlameLoop
ldx ObjectOffset ;reload original enemy offset
jsr GetEnemyOffscreenBits ;get offscreen information
ldy Enemy_SprDataOffset,x ;get OAM data offset
lda Enemy_OffscreenBits ;get enemy object offscreen bits
lsr ;move d0 to carry and result to stack
pha
bcc M3FOfs ;branch if carry not set
lda #$f8 ;otherwise move sprite offscreen, this part likely
sta Sprite_Y_Position+12,y ;residual since flame is only made of three sprites
M3FOfs: pla ;get bits from stack
lsr ;move d1 to carry and move bits back to stack
pha
bcc M2FOfs ;branch if carry not set again
lda #$f8 ;otherwise move third sprite offscreen
sta Sprite_Y_Position+8,y
M2FOfs: pla ;get bits from stack again
lsr ;move d2 to carry and move bits back to stack again
pha
bcc M1FOfs ;branch if carry not set yet again
lda #$f8 ;otherwise move second sprite offscreen
sta Sprite_Y_Position+4,y
M1FOfs: pla ;get bits from stack one last time
lsr ;move d3 to carry
bcc ExFlmeD ;branch if carry not set one last time
lda #$f8
sta Sprite_Y_Position,y ;otherwise move first sprite offscreen
ExFlmeD: rts ;leave
;--------------------------------
RunFireworks:
dec ExplosionTimerCounter,x ;decrement explosion timing counter here
bne SetupExpl ;if not expired, skip this part
lda #$08
sta ExplosionTimerCounter,x ;reset counter
inc ExplosionGfxCounter,x ;increment explosion graphics counter
lda ExplosionGfxCounter,x
cmp #$03 ;check explosion graphics counter
bcs FireworksSoundScore ;if at a certain point, branch to kill this object
SetupExpl: jsr RelativeEnemyPosition ;get relative coordinates of explosion
lda Enemy_Rel_YPos ;copy relative coordinates
sta Fireball_Rel_YPos ;from the enemy object to the fireball object
lda Enemy_Rel_XPos ;first vertical, then horizontal
sta Fireball_Rel_XPos
ldy Enemy_SprDataOffset,x ;get OAM data offset
lda ExplosionGfxCounter,x ;get explosion graphics counter
jsr DrawExplosion_Fireworks ;do a sub to draw the explosion then leave
rts
FireworksSoundScore:
lda #$00 ;disable enemy buffer flag
sta Enemy_Flag,x
lda #Sfx_Blast ;play fireworks/gunfire sound
sta Square2SoundQueue
lda #$05 ;set part of score modifier for 500 points
sta DigitModifier+4
jmp EndAreaPoints ;jump to award points accordingly then leave
;--------------------------------
StarFlagYPosAdder:
.db $00, $00, $08, $08
StarFlagXPosAdder:
.db $00, $08, $00, $08
StarFlagTileData:
.db $54, $55, $56, $57
RunStarFlagObj:
lda #$00 ;initialize enemy frenzy buffer
sta EnemyFrenzyBuffer
lda StarFlagTaskControl ;check star flag object task number here
cmp #$05 ;if greater than 5, branch to exit
bcs StarFlagExit
jsr JumpEngine ;otherwise jump to appropriate sub
.dw StarFlagExit
.dw GameTimerFireworks
.dw AwardGameTimerPoints
.dw RaiseFlagSetoffFWorks
.dw DelayToAreaEnd
GameTimerFireworks:
ldy #$05 ;set default state for star flag object
lda GameTimerDisplay+2 ;get game timer's last digit
cmp #$01
beq SetFWC ;if last digit of game timer set to 1, skip ahead
ldy #$03 ;otherwise load new value for state
cmp #$03
beq SetFWC ;if last digit of game timer set to 3, skip ahead
ldy #$00 ;otherwise load one more potential value for state
cmp #$06
beq SetFWC ;if last digit of game timer set to 6, skip ahead
lda #$ff ;otherwise set value for no fireworks
SetFWC: sta FireworksCounter ;set fireworks counter here
sty Enemy_State,x ;set whatever state we have in star flag object
IncrementSFTask1:
inc StarFlagTaskControl ;increment star flag object task number
StarFlagExit:
rts ;leave
AwardGameTimerPoints:
lda GameTimerDisplay ;check all game timer digits for any intervals left
ora GameTimerDisplay+1
ora GameTimerDisplay+2
beq IncrementSFTask1 ;if no time left on game timer at all, branch to next task
lda FrameCounter
and #%00000100 ;check frame counter for d2 set (skip ahead
beq NoTTick ;for four frames every four frames) branch if not set
lda #Sfx_TimerTick
sta Square2SoundQueue ;load timer tick sound
NoTTick: ldy #$23 ;set offset here to subtract from game timer's last digit
lda #$ff ;set adder here to $ff, or -1, to subtract one
sta DigitModifier+5 ;from the last digit of the game timer
jsr DigitsMathRoutine ;subtract digit
lda #$05 ;set now to add 50 points
sta DigitModifier+5 ;per game timer interval subtracted
EndAreaPoints:
ldy #$0b ;load offset for mario's score by default
lda CurrentPlayer ;check player on the screen
beq ELPGive ;if mario, do not change
ldy #$11 ;otherwise load offset for luigi's score
ELPGive: jsr DigitsMathRoutine ;award 50 points per game timer interval
lda CurrentPlayer ;get player on the screen (or 500 points per
asl ;fireworks explosion if branched here from there)
asl ;shift to high nybble
asl
asl
ora #%00000100 ;add four to set nybble for game timer
jmp UpdateNumber ;jump to print the new score and game timer
RaiseFlagSetoffFWorks:
lda Enemy_Y_Position,x ;check star flag's vertical position
cmp #$72 ;against preset value
bcc SetoffF ;if star flag higher vertically, branch to other code
dec Enemy_Y_Position,x ;otherwise, raise star flag by one pixel
jmp DrawStarFlag ;and skip this part here
SetoffF: lda FireworksCounter ;check fireworks counter
beq DrawFlagSetTimer ;if no fireworks left to go off, skip this part
bmi DrawFlagSetTimer ;if no fireworks set to go off, skip this part
lda #Fireworks
sta EnemyFrenzyBuffer ;otherwise set fireworks object in frenzy queue
DrawStarFlag:
jsr RelativeEnemyPosition ;get relative coordinates of star flag
ldy Enemy_SprDataOffset,x ;get OAM data offset
ldx #$03 ;do four sprites
DSFLoop: lda Enemy_Rel_YPos ;get relative vertical coordinate
clc
adc StarFlagYPosAdder,x ;add Y coordinate adder data
sta Sprite_Y_Position,y ;store as Y coordinate
lda StarFlagTileData,x ;get tile number
sta Sprite_Tilenumber,y ;store as tile number
lda #$22 ;set palette and background priority bits
sta Sprite_Attributes,y ;store as attributes
lda Enemy_Rel_XPos ;get relative horizontal coordinate
clc
adc StarFlagXPosAdder,x ;add X coordinate adder data
sta Sprite_X_Position,y ;store as X coordinate
iny
iny ;increment OAM data offset four bytes
iny ;for next sprite
iny
dex ;move onto next sprite
bpl DSFLoop ;do this until all sprites are done
ldx ObjectOffset ;get enemy object offset and leave
rts
DrawFlagSetTimer:
jsr DrawStarFlag ;do sub to draw star flag
lda #$06
sta EnemyIntervalTimer,x ;set interval timer here
IncrementSFTask2:
inc StarFlagTaskControl ;move onto next task
rts
DelayToAreaEnd:
jsr DrawStarFlag ;do sub to draw star flag
lda EnemyIntervalTimer,x ;if interval timer set in previous task
bne StarFlagExit2 ;not yet expired, branch to leave
lda EventMusicBuffer ;if event music buffer empty,
beq IncrementSFTask2 ;branch to increment task
StarFlagExit2:
rts ;otherwise leave
;--------------------------------
;$00 - used to store horizontal difference between player and piranha plant
MovePiranhaPlant:
lda Enemy_State,x ;check enemy state
bne PutinPipe ;if set at all, branch to leave
lda EnemyFrameTimer,x ;check enemy's timer here
bne PutinPipe ;branch to end if not yet expired
lda PiranhaPlant_MoveFlag,x ;check movement flag
bne SetupToMovePPlant ;if moving, skip to part ahead
lda PiranhaPlant_Y_Speed,x ;if currently rising, branch
bmi ReversePlantSpeed ;to move enemy upwards out of pipe
jsr PlayerEnemyDiff ;get horizontal difference between player and
bpl ChkPlayerNearPipe ;piranha plant, and branch if enemy to right of player
lda $00 ;otherwise get saved horizontal difference
eor #$ff
clc ;and change to two's compliment
adc #$01
sta $00 ;save as new horizontal difference
ChkPlayerNearPipe:
lda $00 ;get saved horizontal difference
cmp #$21
bcc PutinPipe ;if player within a certain distance, branch to leave
ReversePlantSpeed:
lda PiranhaPlant_Y_Speed,x ;get vertical speed
eor #$ff
clc ;change to two's compliment
adc #$01
sta PiranhaPlant_Y_Speed,x ;save as new vertical speed
inc PiranhaPlant_MoveFlag,x ;increment to set movement flag
SetupToMovePPlant:
lda PiranhaPlantDownYPos,x ;get original vertical coordinate (lowest point)
ldy PiranhaPlant_Y_Speed,x ;get vertical speed
bpl RiseFallPiranhaPlant ;branch if moving downwards
lda PiranhaPlantUpYPos,x ;otherwise get other vertical coordinate (highest point)
RiseFallPiranhaPlant:
sta $00 ;save vertical coordinate here
lda FrameCounter ;get frame counter
lsr
bcc PutinPipe ;branch to leave if d0 set (execute code every other frame)
lda TimerControl ;get master timer control
bne PutinPipe ;branch to leave if set (likely not necessary)
lda Enemy_Y_Position,x ;get current vertical coordinate
clc
adc PiranhaPlant_Y_Speed,x ;add vertical speed to move up or down
sta Enemy_Y_Position,x ;save as new vertical coordinate
cmp $00 ;compare against low or high coordinate
bne PutinPipe ;branch to leave if not yet reached
lda #$00
sta PiranhaPlant_MoveFlag,x ;otherwise clear movement flag
lda #$40
sta EnemyFrameTimer,x ;set timer to delay piranha plant movement
PutinPipe:
lda #%00100000 ;set background priority bit in sprite
sta Enemy_SprAttrib,x ;attributes to give illusion of being inside pipe
rts ;then leave
;-------------------------------------------------------------------------------------
;$07 - spinning speed
FirebarSpin:
sta $07 ;save spinning speed here
lda FirebarSpinDirection,x ;check spinning direction
bne SpinCounterClockwise ;if moving counter-clockwise, branch to other part
ldy #$18 ;possibly residual ldy
lda FirebarSpinState_Low,x
clc ;add spinning speed to what would normally be
adc $07 ;the horizontal speed
sta FirebarSpinState_Low,x
lda FirebarSpinState_High,x ;add carry to what would normally be the vertical speed
adc #$00
rts
SpinCounterClockwise:
ldy #$08 ;possibly residual ldy
lda FirebarSpinState_Low,x
sec ;subtract spinning speed to what would normally be
sbc $07 ;the horizontal speed
sta FirebarSpinState_Low,x
lda FirebarSpinState_High,x ;add carry to what would normally be the vertical speed
sbc #$00
rts
;-------------------------------------------------------------------------------------
;$00 - used to hold collision flag, Y movement force + 5 or low byte of name table for rope
;$01 - used to hold high byte of name table for rope
;$02 - used to hold page location of rope
BalancePlatform:
lda Enemy_Y_HighPos,x ;check high byte of vertical position
cmp #$03
bne DoBPl
jmp EraseEnemyObject ;if far below screen, kill the object
DoBPl: lda Enemy_State,x ;get object's state (set to $ff or other platform offset)
bpl CheckBalPlatform ;if doing other balance platform, branch to leave
rts
CheckBalPlatform:
tay ;save offset from state as Y
lda PlatformCollisionFlag,x ;get collision flag of platform
sta $00 ;store here
lda Enemy_MovingDir,x ;get moving direction
beq ChkForFall
jmp PlatformFall ;if set, jump here
ChkForFall:
lda #$2d ;check if platform is above a certain point
cmp Enemy_Y_Position,x
bcc ChkOtherForFall ;if not, branch elsewhere
cpy $00 ;if collision flag is set to same value as
beq MakePlatformFall ;enemy state, branch to make platforms fall
clc
adc #$02 ;otherwise add 2 pixels to vertical position
sta Enemy_Y_Position,x ;of current platform and branch elsewhere
jmp StopPlatforms ;to make platforms stop
MakePlatformFall:
jmp InitPlatformFall ;make platforms fall
ChkOtherForFall:
cmp Enemy_Y_Position,y ;check if other platform is above a certain point
bcc ChkToMoveBalPlat ;if not, branch elsewhere
cpx $00 ;if collision flag is set to same value as
beq MakePlatformFall ;enemy state, branch to make platforms fall
clc
adc #$02 ;otherwise add 2 pixels to vertical position
sta Enemy_Y_Position,y ;of other platform and branch elsewhere
jmp StopPlatforms ;jump to stop movement and do not return
ChkToMoveBalPlat:
lda Enemy_Y_Position,x ;save vertical position to stack
pha
lda PlatformCollisionFlag,x ;get collision flag
bpl ColFlg ;branch if collision
lda Enemy_Y_MoveForce,x
clc ;add $05 to contents of moveforce, whatever they be
adc #$05
sta $00 ;store here
lda Enemy_Y_Speed,x
adc #$00 ;add carry to vertical speed
bmi PlatDn ;branch if moving downwards
bne PlatUp ;branch elsewhere if moving upwards
lda $00
cmp #$0b ;check if there's still a little force left
bcc PlatSt ;if not enough, branch to stop movement
bcs PlatUp ;otherwise keep branch to move upwards
ColFlg: cmp ObjectOffset ;if collision flag matches
beq PlatDn ;current enemy object offset, branch
PlatUp: jsr MovePlatformUp ;do a sub to move upwards
jmp DoOtherPlatform ;jump ahead to remaining code
PlatSt: jsr StopPlatforms ;do a sub to stop movement
jmp DoOtherPlatform ;jump ahead to remaining code
PlatDn: jsr MovePlatformDown ;do a sub to move downwards
DoOtherPlatform:
ldy Enemy_State,x ;get offset of other platform
pla ;get old vertical coordinate from stack
sec
sbc Enemy_Y_Position,x ;get difference of old vs. new coordinate
clc
adc Enemy_Y_Position,y ;add difference to vertical coordinate of other
sta Enemy_Y_Position,y ;platform to move it in the opposite direction
lda PlatformCollisionFlag,x ;if no collision, skip this part here
bmi DrawEraseRope
tax ;put offset which collision occurred here
jsr PositionPlayerOnVPlat ;and use it to position player accordingly
DrawEraseRope:
ldy ObjectOffset ;get enemy object offset
lda Enemy_Y_Speed,y ;check to see if current platform is
ora Enemy_Y_MoveForce,y ;moving at all
beq ExitRp ;if not, skip all of this and branch to leave
ldx VRAM_Buffer1_Offset ;get vram buffer offset
cpx #$20 ;if offset beyond a certain point, go ahead
bcs ExitRp ;and skip this, branch to leave
lda Enemy_Y_Speed,y
pha ;save two copies of vertical speed to stack
pha
jsr SetupPlatformRope ;do a sub to figure out where to put new bg tiles
lda $01 ;write name table address to vram buffer
sta VRAM_Buffer1,x ;first the high byte, then the low
lda $00
sta VRAM_Buffer1+1,x
lda #$02 ;set length for 2 bytes
sta VRAM_Buffer1+2,x
lda Enemy_Y_Speed,y ;if platform moving upwards, branch
bmi EraseR1 ;to do something else
lda #$a2
sta VRAM_Buffer1+3,x ;otherwise put tile numbers for left
lda #$a3 ;and right sides of rope in vram buffer
sta VRAM_Buffer1+4,x
jmp OtherRope ;jump to skip this part
EraseR1: lda #$24 ;put blank tiles in vram buffer
sta VRAM_Buffer1+3,x ;to erase rope
sta VRAM_Buffer1+4,x
OtherRope:
lda Enemy_State,y ;get offset of other platform from state
tay ;use as Y here
pla ;pull second copy of vertical speed from stack
eor #$ff ;invert bits to reverse speed
jsr SetupPlatformRope ;do sub again to figure out where to put bg tiles
lda $01 ;write name table address to vram buffer
sta VRAM_Buffer1+5,x ;this time we're doing putting tiles for
lda $00 ;the other platform
sta VRAM_Buffer1+6,x
lda #$02
sta VRAM_Buffer1+7,x ;set length again for 2 bytes
pla ;pull first copy of vertical speed from stack
bpl EraseR2 ;if moving upwards (note inversion earlier), skip this
lda #$a2
sta VRAM_Buffer1+8,x ;otherwise put tile numbers for left
lda #$a3 ;and right sides of rope in vram
sta VRAM_Buffer1+9,x ;transfer buffer
jmp EndRp ;jump to skip this part
EraseR2: lda #$24 ;put blank tiles in vram buffer
sta VRAM_Buffer1+8,x ;to erase rope
sta VRAM_Buffer1+9,x
EndRp: lda #$00 ;put null terminator at the end
sta VRAM_Buffer1+10,x
lda VRAM_Buffer1_Offset ;add ten bytes to the vram buffer offset
clc ;and store
adc #10
sta VRAM_Buffer1_Offset
ExitRp: ldx ObjectOffset ;get enemy object buffer offset and leave
rts
SetupPlatformRope:
pha ;save second/third copy to stack
lda Enemy_X_Position,y ;get horizontal coordinate
clc
adc #$08 ;add eight pixels
ldx SecondaryHardMode ;if secondary hard mode flag set,
bne GetLRp ;use coordinate as-is
clc
adc #$10 ;otherwise add sixteen more pixels
GetLRp: pha ;save modified horizontal coordinate to stack
lda Enemy_PageLoc,y
adc #$00 ;add carry to page location
sta $02 ;and save here
pla ;pull modified horizontal coordinate
and #%11110000 ;from the stack, mask out low nybble
lsr ;and shift three bits to the right
lsr
lsr
sta $00 ;store result here as part of name table low byte
ldx Enemy_Y_Position,y ;get vertical coordinate
pla ;get second/third copy of vertical speed from stack
bpl GetHRp ;skip this part if moving downwards or not at all
txa
clc
adc #$08 ;add eight to vertical coordinate and
tax ;save as X
GetHRp: txa ;move vertical coordinate to A
ldx VRAM_Buffer1_Offset ;get vram buffer offset
asl
rol ;rotate d7 to d0 and d6 into carry
pha ;save modified vertical coordinate to stack
rol ;rotate carry to d0, thus d7 and d6 are at 2 LSB
and #%00000011 ;mask out all bits but d7 and d6, then set
ora #%00100000 ;d5 to get appropriate high byte of name table
sta $01 ;address, then store
lda $02 ;get saved page location from earlier
and #$01 ;mask out all but LSB
asl
asl ;shift twice to the left and save with the
ora $01 ;rest of the bits of the high byte, to get
sta $01 ;the proper name table and the right place on it
pla ;get modified vertical coordinate from stack
and #%11100000 ;mask out low nybble and LSB of high nybble
clc
adc $00 ;add to horizontal part saved here
sta $00 ;save as name table low byte
lda Enemy_Y_Position,y
cmp #$e8 ;if vertical position not below the
bcc ExPRp ;bottom of the screen, we're done, branch to leave
lda $00
and #%10111111 ;mask out d6 of low byte of name table address
sta $00
ExPRp: rts ;leave!
InitPlatformFall:
tya ;move offset of other platform from Y to X
tax
jsr GetEnemyOffscreenBits ;get offscreen bits
lda #$06
jsr SetupFloateyNumber ;award 1000 points to player
lda Player_Rel_XPos
sta FloateyNum_X_Pos,x ;put floatey number coordinates where player is
lda Player_Y_Position
sta FloateyNum_Y_Pos,x
lda #$01 ;set moving direction as flag for
sta Enemy_MovingDir,x ;falling platforms
StopPlatforms:
jsr InitVStf ;initialize vertical speed and low byte
sta Enemy_Y_Speed,y ;for both platforms and leave
sta Enemy_Y_MoveForce,y
rts
PlatformFall:
tya ;save offset for other platform to stack
pha
jsr MoveFallingPlatform ;make current platform fall
pla
tax ;pull offset from stack and save to X
jsr MoveFallingPlatform ;make other platform fall
ldx ObjectOffset
lda PlatformCollisionFlag,x ;if player not standing on either platform,
bmi ExPF ;skip this part
tax ;transfer collision flag offset as offset to X
jsr PositionPlayerOnVPlat ;and position player appropriately
ExPF: ldx ObjectOffset ;get enemy object buffer offset and leave
rts
;--------------------------------
YMovingPlatform:
lda Enemy_Y_Speed,x ;if platform moving up or down, skip ahead to
ora Enemy_Y_MoveForce,x ;check on other position
bne ChkYCenterPos
sta Enemy_YMF_Dummy,x ;initialize dummy variable
lda Enemy_Y_Position,x
cmp YPlatformTopYPos,x ;if current vertical position => top position, branch
bcs ChkYCenterPos ;ahead of all this
lda FrameCounter
and #%00000111 ;check for every eighth frame
bne SkipIY
inc Enemy_Y_Position,x ;increase vertical position every eighth frame
SkipIY: jmp ChkYPCollision ;skip ahead to last part
ChkYCenterPos:
lda Enemy_Y_Position,x ;if current vertical position < central position, branch
cmp YPlatformCenterYPos,x ;to slow ascent/move downwards
bcc YMDown
jsr MovePlatformUp ;otherwise start slowing descent/moving upwards
jmp ChkYPCollision
YMDown: jsr MovePlatformDown ;start slowing ascent/moving downwards
ChkYPCollision:
lda PlatformCollisionFlag,x ;if collision flag not set here, branch
bmi ExYPl ;to leave
jsr PositionPlayerOnVPlat ;otherwise position player appropriately
ExYPl: rts ;leave
;--------------------------------
;$00 - used as adder to position player hotizontally
XMovingPlatform:
lda #$0e ;load preset maximum value for secondary counter
jsr XMoveCntr_Platform ;do a sub to increment counters for movement
jsr MoveWithXMCntrs ;do a sub to move platform accordingly, and return value
lda PlatformCollisionFlag,x ;if no collision with player,
bmi ExXMP ;branch ahead to leave
PositionPlayerOnHPlat:
lda Player_X_Position
clc ;add saved value from second subroutine to
adc $00 ;current player's position to position
sta Player_X_Position ;player accordingly in horizontal position
lda Player_PageLoc ;get player's page location
ldy $00 ;check to see if saved value here is positive or negative
bmi PPHSubt ;if negative, branch to subtract
adc #$00 ;otherwise add carry to page location
jmp SetPVar ;jump to skip subtraction
PPHSubt: sbc #$00 ;subtract borrow from page location
SetPVar: sta Player_PageLoc ;save result to player's page location
sty Platform_X_Scroll ;put saved value from second sub here to be used later
jsr PositionPlayerOnVPlat ;position player vertically and appropriately
ExXMP: rts ;and we are done here
;--------------------------------
DropPlatform:
lda PlatformCollisionFlag,x ;if no collision between platform and player
bmi ExDPl ;occurred, just leave without moving anything
jsr MoveDropPlatform ;otherwise do a sub to move platform down very quickly
jsr PositionPlayerOnVPlat ;do a sub to position player appropriately
ExDPl: rts ;leave
;--------------------------------
;$00 - residual value from sub
RightPlatform:
jsr MoveEnemyHorizontally ;move platform with current horizontal speed, if any
sta $00 ;store saved value here (residual code)
lda PlatformCollisionFlag,x ;check collision flag, if no collision between player
bmi ExRPl ;and platform, branch ahead, leave speed unaltered
lda #$10
sta Enemy_X_Speed,x ;otherwise set new speed (gets moving if motionless)
jsr PositionPlayerOnHPlat ;use saved value from earlier sub to position player
ExRPl: rts ;then leave
;--------------------------------
MoveLargeLiftPlat:
jsr MoveLiftPlatforms ;execute common to all large and small lift platforms
jmp ChkYPCollision ;branch to position player correctly
MoveSmallPlatform:
jsr MoveLiftPlatforms ;execute common to all large and small lift platforms
jmp ChkSmallPlatCollision ;branch to position player correctly
MoveLiftPlatforms:
lda TimerControl ;if master timer control set, skip all of this
bne ExLiftP ;and branch to leave
lda Enemy_YMF_Dummy,x
clc ;add contents of movement amount to whatever's here
adc Enemy_Y_MoveForce,x
sta Enemy_YMF_Dummy,x
lda Enemy_Y_Position,x ;add whatever vertical speed is set to current
adc Enemy_Y_Speed,x ;vertical position plus carry to move up or down
sta Enemy_Y_Position,x ;and then leave
rts
ChkSmallPlatCollision:
lda PlatformCollisionFlag,x ;get bounding box counter saved in collision flag
beq ExLiftP ;if none found, leave player position alone
jsr PositionPlayerOnS_Plat ;use to position player correctly
ExLiftP: rts ;then leave
;-------------------------------------------------------------------------------------
;$00 - page location of extended left boundary
;$01 - extended left boundary position
;$02 - page location of extended right boundary
;$03 - extended right boundary position
OffscreenBoundsCheck:
lda Enemy_ID,x ;check for cheep-cheep object
cmp #FlyingCheepCheep ;branch to leave if found
beq ExScrnBd
lda ScreenLeft_X_Pos ;get horizontal coordinate for left side of screen
ldy Enemy_ID,x
cpy #HammerBro ;check for hammer bro object
beq LimitB
cpy #PiranhaPlant ;check for piranha plant object
bne ExtendLB ;these two will be erased sooner than others if too far left
LimitB: adc #$38 ;add 56 pixels to coordinate if hammer bro or piranha plant
ExtendLB: sbc #$48 ;subtract 72 pixels regardless of enemy object
sta $01 ;store result here
lda ScreenLeft_PageLoc
sbc #$00 ;subtract borrow from page location of left side
sta $00 ;store result here
lda ScreenRight_X_Pos ;add 72 pixels to the right side horizontal coordinate
adc #$48
sta $03 ;store result here
lda ScreenRight_PageLoc
adc #$00 ;then add the carry to the page location
sta $02 ;and store result here
lda Enemy_X_Position,x ;compare horizontal coordinate of the enemy object
cmp $01 ;to modified horizontal left edge coordinate to get carry
lda Enemy_PageLoc,x
sbc $00 ;then subtract it from the page coordinate of the enemy object
bmi TooFar ;if enemy object is too far left, branch to erase it
lda Enemy_X_Position,x ;compare horizontal coordinate of the enemy object
cmp $03 ;to modified horizontal right edge coordinate to get carry
lda Enemy_PageLoc,x
sbc $02 ;then subtract it from the page coordinate of the enemy object
bmi ExScrnBd ;if enemy object is on the screen, leave, do not erase enemy
lda Enemy_State,x ;if at this point, enemy is offscreen to the right, so check
cmp #HammerBro ;if in state used by spiny's egg, do not erase
beq ExScrnBd
cpy #PiranhaPlant ;if piranha plant, do not erase
beq ExScrnBd
cpy #FlagpoleFlagObject ;if flagpole flag, do not erase
beq ExScrnBd
cpy #StarFlagObject ;if star flag, do not erase
beq ExScrnBd
cpy #JumpspringObject ;if jumpspring, do not erase
beq ExScrnBd ;erase all others too far to the right
TooFar: jsr EraseEnemyObject ;erase object if necessary
ExScrnBd: rts ;leave
;-------------------------------------------------------------------------------------
;some unused space
.db $ff, $ff, $ff
;-------------------------------------------------------------------------------------
;$01 - enemy buffer offset
FireballEnemyCollision:
lda Fireball_State,x ;check to see if fireball state is set at all
beq ExitFBallEnemy ;branch to leave if not
asl
bcs ExitFBallEnemy ;branch to leave also if d7 in state is set
lda FrameCounter
lsr ;get LSB of frame counter
bcs ExitFBallEnemy ;branch to leave if set (do routine every other frame)
txa
asl ;multiply fireball offset by four
asl
clc
adc #$1c ;then add $1c or 28 bytes to it
tay ;to use fireball's bounding box coordinates
ldx #$04
FireballEnemyCDLoop:
stx $01 ;store enemy object offset here
tya
pha ;push fireball offset to the stack
lda Enemy_State,x
and #%00100000 ;check to see if d5 is set in enemy state
bne NoFToECol ;if so, skip to next enemy slot
lda Enemy_Flag,x ;check to see if buffer flag is set
beq NoFToECol ;if not, skip to next enemy slot
lda Enemy_ID,x ;check enemy identifier
cmp #$24
bcc GoombaDie ;if < $24, branch to check further
cmp #$2b
bcc NoFToECol ;if in range $24-$2a, skip to next enemy slot
GoombaDie: cmp #Goomba ;check for goomba identifier
bne NotGoomba ;if not found, continue with code
lda Enemy_State,x ;otherwise check for defeated state
cmp #$02 ;if stomped or otherwise defeated,
bcs NoFToECol ;skip to next enemy slot
NotGoomba: lda EnemyOffscrBitsMasked,x ;if any masked offscreen bits set,
bne NoFToECol ;skip to next enemy slot
txa
asl ;otherwise multiply enemy offset by four
asl
clc
adc #$04 ;add 4 bytes to it
tax ;to use enemy's bounding box coordinates
jsr SprObjectCollisionCore ;do fireball-to-enemy collision detection
ldx ObjectOffset ;return fireball's original offset
bcc NoFToECol ;if carry clear, no collision, thus do next enemy slot
lda #%10000000
sta Fireball_State,x ;set d7 in enemy state
ldx $01 ;get enemy offset
jsr HandleEnemyFBallCol ;jump to handle fireball to enemy collision
NoFToECol: pla ;pull fireball offset from stack
tay ;put it in Y
ldx $01 ;get enemy object offset
dex ;decrement it
bpl FireballEnemyCDLoop ;loop back until collision detection done on all enemies
ExitFBallEnemy:
ldx ObjectOffset ;get original fireball offset and leave
rts
BowserIdentities:
.db Goomba, GreenKoopa, BuzzyBeetle, Spiny, Lakitu, Bloober, HammerBro, Bowser
HandleEnemyFBallCol:
jsr RelativeEnemyPosition ;get relative coordinate of enemy
ldx $01 ;get current enemy object offset
lda Enemy_Flag,x ;check buffer flag for d7 set
bpl ChkBuzzyBeetle ;branch if not set to continue
and #%00001111 ;otherwise mask out high nybble and
tax ;use low nybble as enemy offset
lda Enemy_ID,x
cmp #Bowser ;check enemy identifier for bowser
beq HurtBowser ;branch if found
ldx $01 ;otherwise retrieve current enemy offset
ChkBuzzyBeetle:
lda Enemy_ID,x
cmp #BuzzyBeetle ;check for buzzy beetle
beq ExHCF ;branch if found to leave (buzzy beetles fireproof)
cmp #Bowser ;check for bowser one more time (necessary if d7 of flag was clear)
bne ChkOtherEnemies ;if not found, branch to check other enemies
HurtBowser:
dec BowserHitPoints ;decrement bowser's hit points
bne ExHCF ;if bowser still has hit points, branch to leave
jsr InitVStf ;otherwise do sub to init vertical speed and movement force
sta Enemy_X_Speed,x ;initialize horizontal speed
sta EnemyFrenzyBuffer ;init enemy frenzy buffer
lda #$fe
sta Enemy_Y_Speed,x ;set vertical speed to make defeated bowser jump a little
ldy WorldNumber ;use world number as offset
lda BowserIdentities,y ;get enemy identifier to replace bowser with
sta Enemy_ID,x ;set as new enemy identifier
lda #$20 ;set A to use starting value for state
cpy #$03 ;check to see if using offset of 3 or more
bcs SetDBSte ;branch if so
ora #$03 ;otherwise add 3 to enemy state
SetDBSte: sta Enemy_State,x ;set defeated enemy state
lda #Sfx_BowserFall
sta Square2SoundQueue ;load bowser defeat sound
ldx $01 ;get enemy offset
lda #$09 ;award 5000 points to player for defeating bowser
bne EnemySmackScore ;unconditional branch to award points
ChkOtherEnemies:
cmp #BulletBill_FrenzyVar
beq ExHCF ;branch to leave if bullet bill (frenzy variant)
cmp #Podoboo
beq ExHCF ;branch to leave if podoboo
cmp #$15
bcs ExHCF ;branch to leave if identifier => $15
ShellOrBlockDefeat:
lda Enemy_ID,x ;check for piranha plant
cmp #PiranhaPlant
bne StnE ;branch if not found
lda Enemy_Y_Position,x
adc #$18 ;add 24 pixels to enemy object's vertical position
sta Enemy_Y_Position,x
StnE: jsr ChkToStunEnemies ;do yet another sub
lda Enemy_State,x
and #%00011111 ;mask out 2 MSB of enemy object's state
ora #%00100000 ;set d5 to defeat enemy and save as new state
sta Enemy_State,x
lda #$02 ;award 200 points by default
ldy Enemy_ID,x ;check for hammer bro
cpy #HammerBro
bne GoombaPoints ;branch if not found
lda #$06 ;award 1000 points for hammer bro
GoombaPoints:
cpy #Goomba ;check for goomba
bne EnemySmackScore ;branch if not found
lda #$01 ;award 100 points for goomba
EnemySmackScore:
jsr SetupFloateyNumber ;update necessary score variables
lda #Sfx_EnemySmack ;play smack enemy sound
sta Square1SoundQueue
ExHCF: rts ;and now let's leave
;-------------------------------------------------------------------------------------
PlayerHammerCollision:
lda FrameCounter ;get frame counter
lsr ;shift d0 into carry
bcc ExPHC ;branch to leave if d0 not set to execute every other frame
lda TimerControl ;if either master timer control
ora Misc_OffscreenBits ;or any offscreen bits for hammer are set,
bne ExPHC ;branch to leave
txa
asl ;multiply misc object offset by four
asl
clc
adc #$24 ;add 36 or $24 bytes to get proper offset
tay ;for misc object bounding box coordinates
jsr PlayerCollisionCore ;do player-to-hammer collision detection
ldx ObjectOffset ;get misc object offset
bcc ClHCol ;if no collision, then branch
lda Misc_Collision_Flag,x ;otherwise read collision flag
bne ExPHC ;if collision flag already set, branch to leave
lda #$01
sta Misc_Collision_Flag,x ;otherwise set collision flag now
lda Misc_X_Speed,x
eor #$ff ;get two's compliment of
clc ;hammer's horizontal speed
adc #$01
sta Misc_X_Speed,x ;set to send hammer flying the opposite direction
lda StarInvincibleTimer ;if star mario invincibility timer set,
bne ExPHC ;branch to leave
jmp InjurePlayer ;otherwise jump to hurt player, do not return
ClHCol: lda #$00 ;clear collision flag
sta Misc_Collision_Flag,x
ExPHC: rts
;-------------------------------------------------------------------------------------
HandlePowerUpCollision:
jsr EraseEnemyObject ;erase the power-up object
lda #$06
jsr SetupFloateyNumber ;award 1000 points to player by default
lda #Sfx_PowerUpGrab
sta Square2SoundQueue ;play the power-up sound
lda PowerUpType ;check power-up type
cmp #$02
bcc Shroom_Flower_PUp ;if mushroom or fire flower, branch
cmp #$03
beq SetFor1Up ;if 1-up mushroom, branch
lda #$23 ;otherwise set star mario invincibility
sta StarInvincibleTimer ;timer, and load the star mario music
lda #StarPowerMusic ;into the area music queue, then leave
sta AreaMusicQueue
rts
Shroom_Flower_PUp:
lda PlayerStatus ;if player status = small, branch
beq UpToSuper
cmp #$01 ;if player status not super, leave
bne NoPUp
ldx ObjectOffset ;get enemy offset, not necessary
lda #$02 ;set player status to fiery
sta PlayerStatus
jsr GetPlayerColors ;run sub to change colors of player
ldx ObjectOffset ;get enemy offset again, and again not necessary
lda #$0c ;set value to be used by subroutine tree (fiery)
jmp UpToFiery ;jump to set values accordingly
SetFor1Up:
lda #$0b ;change 1000 points into 1-up instead
sta FloateyNum_Control,x ;and then leave
rts
UpToSuper:
lda #$01 ;set player status to super
sta PlayerStatus
lda #$09 ;set value to be used by subroutine tree (super)
UpToFiery:
ldy #$00 ;set value to be used as new player state
jsr SetPRout ;set values to stop certain things in motion
NoPUp: rts
;--------------------------------
ResidualXSpdData:
.db $18, $e8
KickedShellXSpdData:
.db $30, $d0
DemotedKoopaXSpdData:
.db $08, $f8
PlayerEnemyCollision:
lda FrameCounter ;check counter for d0 set
lsr
bcs NoPUp ;if set, branch to leave
jsr CheckPlayerVertical ;if player object is completely offscreen or
bcs NoPECol ;if down past 224th pixel row, branch to leave
lda EnemyOffscrBitsMasked,x ;if current enemy is offscreen by any amount,
bne NoPECol ;go ahead and branch to leave
lda GameEngineSubroutine
cmp #$08 ;if not set to run player control routine
bne NoPECol ;on next frame, branch to leave
lda Enemy_State,x
and #%00100000 ;if enemy state has d5 set, branch to leave
bne NoPECol
jsr GetEnemyBoundBoxOfs ;get bounding box offset for current enemy object
jsr PlayerCollisionCore ;do collision detection on player vs. enemy
ldx ObjectOffset ;get enemy object buffer offset
bcs CheckForPUpCollision ;if collision, branch past this part here
lda Enemy_CollisionBits,x
and #%11111110 ;otherwise, clear d0 of current enemy object's
sta Enemy_CollisionBits,x ;collision bit
NoPECol: rts
CheckForPUpCollision:
ldy Enemy_ID,x
cpy #PowerUpObject ;check for power-up object
bne EColl ;if not found, branch to next part
jmp HandlePowerUpCollision ;otherwise, unconditional jump backwards
EColl: lda StarInvincibleTimer ;if star mario invincibility timer expired,
beq HandlePECollisions ;perform task here, otherwise kill enemy like
jmp ShellOrBlockDefeat ;hit with a shell, or from beneath
KickedShellPtsData:
.db $0a, $06, $04
HandlePECollisions:
lda Enemy_CollisionBits,x ;check enemy collision bits for d0 set
and #%00000001 ;or for being offscreen at all
ora EnemyOffscrBitsMasked,x
bne ExPEC ;branch to leave if either is true
lda #$01
ora Enemy_CollisionBits,x ;otherwise set d0 now
sta Enemy_CollisionBits,x
cpy #Spiny ;branch if spiny
beq ChkForPlayerInjury
cpy #PiranhaPlant ;branch if piranha plant
beq InjurePlayer
cpy #Podoboo ;branch if podoboo
beq InjurePlayer
cpy #BulletBill_CannonVar ;branch if bullet bill
beq ChkForPlayerInjury
cpy #$15 ;branch if object => $15
bcs InjurePlayer
lda AreaType ;branch if water type level
beq InjurePlayer
lda Enemy_State,x ;branch if d7 of enemy state was set
asl
bcs ChkForPlayerInjury
lda Enemy_State,x ;mask out all but 3 LSB of enemy state
and #%00000111
cmp #$02 ;branch if enemy is in normal or falling state
bcc ChkForPlayerInjury
lda Enemy_ID,x ;branch to leave if goomba in defeated state
cmp #Goomba
beq ExPEC
lda #Sfx_EnemySmack ;play smack enemy sound
sta Square1SoundQueue
lda Enemy_State,x ;set d7 in enemy state, thus become moving shell
ora #%10000000
sta Enemy_State,x
jsr EnemyFacePlayer ;set moving direction and get offset
lda KickedShellXSpdData,y ;load and set horizontal speed data with offset
sta Enemy_X_Speed,x
lda #$03 ;add three to whatever the stomp counter contains
clc ;to give points for kicking the shell
adc StompChainCounter
ldy EnemyIntervalTimer,x ;check shell enemy's timer
cpy #$03 ;if above a certain point, branch using the points
bcs KSPts ;data obtained from the stomp counter + 3
lda KickedShellPtsData,y ;otherwise, set points based on proximity to timer expiration
KSPts: jsr SetupFloateyNumber ;set values for floatey number now
ExPEC: rts ;leave!!!
ChkForPlayerInjury:
lda Player_Y_Speed ;check player's vertical speed
bmi ChkInj ;perform procedure below if player moving upwards
bne EnemyStomped ;or not at all, and branch elsewhere if moving downwards
ChkInj: lda Enemy_ID,x ;branch if enemy object < $07
cmp #Bloober
bcc ChkETmrs
lda Player_Y_Position ;add 12 pixels to player's vertical position
clc
adc #$0c
cmp Enemy_Y_Position,x ;compare modified player's position to enemy's position
bcc EnemyStomped ;branch if this player's position above (less than) enemy's
ChkETmrs: lda StompTimer ;check stomp timer
bne EnemyStomped ;branch if set
lda InjuryTimer ;check to see if injured invincibility timer still
bne ExInjColRoutines ;counting down, and branch elsewhere to leave if so
lda Player_Rel_XPos
cmp Enemy_Rel_XPos ;if player's relative position to the left of enemy's
bcc TInjE ;relative position, branch here
jmp ChkEnemyFaceRight ;otherwise do a jump here
TInjE: lda Enemy_MovingDir,x ;if enemy moving towards the left,
cmp #$01 ;branch, otherwise do a jump here
bne InjurePlayer ;to turn the enemy around
jmp LInj
InjurePlayer:
lda InjuryTimer ;check again to see if injured invincibility timer is
bne ExInjColRoutines ;at zero, and branch to leave if so
ForceInjury:
ldx PlayerStatus ;check player's status
beq KillPlayer ;branch if small
sta PlayerStatus ;otherwise set player's status to small
lda #$08
sta InjuryTimer ;set injured invincibility timer
asl
sta Square1SoundQueue ;play pipedown/injury sound
jsr GetPlayerColors ;change player's palette if necessary
lda #$0a ;set subroutine to run on next frame
SetKRout: ldy #$01 ;set new player state
SetPRout: sta GameEngineSubroutine ;load new value to run subroutine on next frame
sty Player_State ;store new player state
ldy #$ff
sty TimerControl ;set master timer control flag to halt timers
iny
sty ScrollAmount ;initialize scroll speed
ExInjColRoutines:
ldx ObjectOffset ;get enemy offset and leave
rts
KillPlayer:
stx Player_X_Speed ;halt player's horizontal movement by initializing speed
inx
stx EventMusicQueue ;set event music queue to death music
lda #$fc
sta Player_Y_Speed ;set new vertical speed
lda #$0b ;set subroutine to run on next frame
bne SetKRout ;branch to set player's state and other things
StompedEnemyPtsData:
.db $02, $06, $05, $06
EnemyStomped:
lda Enemy_ID,x ;check for spiny, branch to hurt player
cmp #Spiny ;if found
beq InjurePlayer
lda #Sfx_EnemyStomp ;otherwise play stomp/swim sound
sta Square1SoundQueue
lda Enemy_ID,x
ldy #$00 ;initialize points data offset for stomped enemies
cmp #FlyingCheepCheep ;branch for cheep-cheep
beq EnemyStompedPts
cmp #BulletBill_FrenzyVar ;branch for either bullet bill object
beq EnemyStompedPts
cmp #BulletBill_CannonVar
beq EnemyStompedPts
cmp #Podoboo ;branch for podoboo (this branch is logically impossible
beq EnemyStompedPts ;for cpu to take due to earlier checking of podoboo)
iny ;increment points data offset
cmp #HammerBro ;branch for hammer bro
beq EnemyStompedPts
iny ;increment points data offset
cmp #Lakitu ;branch for lakitu
beq EnemyStompedPts
iny ;increment points data offset
cmp #Bloober ;branch if NOT bloober
bne ChkForDemoteKoopa
EnemyStompedPts:
lda StompedEnemyPtsData,y ;load points data using offset in Y
jsr SetupFloateyNumber ;run sub to set floatey number controls
lda Enemy_MovingDir,x
pha ;save enemy movement direction to stack
jsr SetStun ;run sub to kill enemy
pla
sta Enemy_MovingDir,x ;return enemy movement direction from stack
lda #%00100000
sta Enemy_State,x ;set d5 in enemy state
jsr InitVStf ;nullify vertical speed, physics-related thing,
sta Enemy_X_Speed,x ;and horizontal speed
lda #$fd ;set player's vertical speed, to give bounce
sta Player_Y_Speed
rts
ChkForDemoteKoopa:
cmp #$09 ;branch elsewhere if enemy object < $09
bcc HandleStompedShellE
and #%00000001 ;demote koopa paratroopas to ordinary troopas
sta Enemy_ID,x
ldy #$00 ;return enemy to normal state
sty Enemy_State,x
lda #$03 ;award 400 points to the player
jsr SetupFloateyNumber
jsr InitVStf ;nullify physics-related thing and vertical speed
jsr EnemyFacePlayer ;turn enemy around if necessary
lda DemotedKoopaXSpdData,y
sta Enemy_X_Speed,x ;set appropriate moving speed based on direction
jmp SBnce ;then move onto something else
RevivalRateData:
.db $10, $0b
HandleStompedShellE:
lda #$04 ;set defeated state for enemy
sta Enemy_State,x
inc StompChainCounter ;increment the stomp counter
lda StompChainCounter ;add whatever is in the stomp counter
clc ;to whatever is in the stomp timer
adc StompTimer
jsr SetupFloateyNumber ;award points accordingly
inc StompTimer ;increment stomp timer of some sort
ldy PrimaryHardMode ;check primary hard mode flag
lda RevivalRateData,y ;load timer setting according to flag
sta EnemyIntervalTimer,x ;set as enemy timer to revive stomped enemy
SBnce: lda #$fc ;set player's vertical speed for bounce
sta Player_Y_Speed ;and then leave!!!
rts
ChkEnemyFaceRight:
lda Enemy_MovingDir,x ;check to see if enemy is moving to the right
cmp #$01
bne LInj ;if not, branch
jmp InjurePlayer ;otherwise go back to hurt player
LInj: jsr EnemyTurnAround ;turn the enemy around, if necessary
jmp InjurePlayer ;go back to hurt player
EnemyFacePlayer:
ldy #$01 ;set to move right by default
jsr PlayerEnemyDiff ;get horizontal difference between player and enemy
bpl SFcRt ;if enemy is to the right of player, do not increment
iny ;otherwise, increment to set to move to the left
SFcRt: sty Enemy_MovingDir,x ;set moving direction here
dey ;then decrement to use as a proper offset
rts
SetupFloateyNumber:
sta FloateyNum_Control,x ;set number of points control for floatey numbers
lda #$30
sta FloateyNum_Timer,x ;set timer for floatey numbers
lda Enemy_Y_Position,x
sta FloateyNum_Y_Pos,x ;set vertical coordinate
lda Enemy_Rel_XPos
sta FloateyNum_X_Pos,x ;set horizontal coordinate and leave
ExSFN: rts
;-------------------------------------------------------------------------------------
;$01 - used to hold enemy offset for second enemy
SetBitsMask:
.db %10000000, %01000000, %00100000, %00010000, %00001000, %00000100, %00000010
ClearBitsMask:
.db %01111111, %10111111, %11011111, %11101111, %11110111, %11111011, %11111101
EnemiesCollision:
lda FrameCounter ;check counter for d0 set
lsr
bcc ExSFN ;if d0 not set, leave
lda AreaType
beq ExSFN ;if water area type, leave
lda Enemy_ID,x
cmp #$15 ;if enemy object => $15, branch to leave
bcs ExitECRoutine
cmp #Lakitu ;if lakitu, branch to leave
beq ExitECRoutine
cmp #PiranhaPlant ;if piranha plant, branch to leave
beq ExitECRoutine
lda EnemyOffscrBitsMasked,x ;if masked offscreen bits nonzero, branch to leave
bne ExitECRoutine
jsr GetEnemyBoundBoxOfs ;otherwise, do sub, get appropriate bounding box offset for
dex ;first enemy we're going to compare, then decrement for second
bmi ExitECRoutine ;branch to leave if there are no other enemies
ECLoop: stx $01 ;save enemy object buffer offset for second enemy here
tya ;save first enemy's bounding box offset to stack
pha
lda Enemy_Flag,x ;check enemy object enable flag
beq ReadyNextEnemy ;branch if flag not set
lda Enemy_ID,x
cmp #$15 ;check for enemy object => $15
bcs ReadyNextEnemy ;branch if true
cmp #Lakitu
beq ReadyNextEnemy ;branch if enemy object is lakitu
cmp #PiranhaPlant
beq ReadyNextEnemy ;branch if enemy object is piranha plant
lda EnemyOffscrBitsMasked,x
bne ReadyNextEnemy ;branch if masked offscreen bits set
txa ;get second enemy object's bounding box offset
asl ;multiply by four, then add four
asl
clc
adc #$04
tax ;use as new contents of X
jsr SprObjectCollisionCore ;do collision detection using the two enemies here
ldx ObjectOffset ;use first enemy offset for X
ldy $01 ;use second enemy offset for Y
bcc NoEnemyCollision ;if carry clear, no collision, branch ahead of this
lda Enemy_State,x
ora Enemy_State,y ;check both enemy states for d7 set
and #%10000000
bne YesEC ;branch if at least one of them is set
lda Enemy_CollisionBits,y ;load first enemy's collision-related bits
and SetBitsMask,x ;check to see if bit connected to second enemy is
bne ReadyNextEnemy ;already set, and move onto next enemy slot if set
lda Enemy_CollisionBits,y
ora SetBitsMask,x ;if the bit is not set, set it now
sta Enemy_CollisionBits,y
YesEC: jsr ProcEnemyCollisions ;react according to the nature of collision
jmp ReadyNextEnemy ;move onto next enemy slot
NoEnemyCollision:
lda Enemy_CollisionBits,y ;load first enemy's collision-related bits
and ClearBitsMask,x ;clear bit connected to second enemy
sta Enemy_CollisionBits,y ;then move onto next enemy slot
ReadyNextEnemy:
pla ;get first enemy's bounding box offset from the stack
tay ;use as Y again
ldx $01 ;get and decrement second enemy's object buffer offset
dex
bpl ECLoop ;loop until all enemy slots have been checked
ExitECRoutine:
ldx ObjectOffset ;get enemy object buffer offset
rts ;leave
ProcEnemyCollisions:
lda Enemy_State,y ;check both enemy states for d5 set
ora Enemy_State,x
and #%00100000 ;if d5 is set in either state, or both, branch
bne ExitProcessEColl ;to leave and do nothing else at this point
lda Enemy_State,x
cmp #$06 ;if second enemy state < $06, branch elsewhere
bcc ProcSecondEnemyColl
lda Enemy_ID,x ;check second enemy identifier for hammer bro
cmp #HammerBro ;if hammer bro found in alt state, branch to leave
beq ExitProcessEColl
lda Enemy_State,y ;check first enemy state for d7 set
asl
bcc ShellCollisions ;branch if d7 is clear
lda #$06
jsr SetupFloateyNumber ;award 1000 points for killing enemy
jsr ShellOrBlockDefeat ;then kill enemy, then load
ldy $01 ;original offset of second enemy
ShellCollisions:
tya ;move Y to X
tax
jsr ShellOrBlockDefeat ;kill second enemy
ldx ObjectOffset
lda ShellChainCounter,x ;get chain counter for shell
clc
adc #$04 ;add four to get appropriate point offset
ldx $01
jsr SetupFloateyNumber ;award appropriate number of points for second enemy
ldx ObjectOffset ;load original offset of first enemy
inc ShellChainCounter,x ;increment chain counter for additional enemies
ExitProcessEColl:
rts ;leave!!!
ProcSecondEnemyColl:
lda Enemy_State,y ;if first enemy state < $06, branch elsewhere
cmp #$06
bcc MoveEOfs
lda Enemy_ID,y ;check first enemy identifier for hammer bro
cmp #HammerBro ;if hammer bro found in alt state, branch to leave
beq ExitProcessEColl
jsr ShellOrBlockDefeat ;otherwise, kill first enemy
ldy $01
lda ShellChainCounter,y ;get chain counter for shell
clc
adc #$04 ;add four to get appropriate point offset
ldx ObjectOffset
jsr SetupFloateyNumber ;award appropriate number of points for first enemy
ldx $01 ;load original offset of second enemy
inc ShellChainCounter,x ;increment chain counter for additional enemies
rts ;leave!!!
MoveEOfs:
tya ;move Y ($01) to X
tax
jsr EnemyTurnAround ;do the sub here using value from $01
ldx ObjectOffset ;then do it again using value from $08
EnemyTurnAround:
lda Enemy_ID,x ;check for specific enemies
cmp #PiranhaPlant
beq ExTA ;if piranha plant, leave
cmp #Lakitu
beq ExTA ;if lakitu, leave
cmp #HammerBro
beq ExTA ;if hammer bro, leave
cmp #Spiny
beq RXSpd ;if spiny, turn it around
cmp #GreenParatroopaJump
beq RXSpd ;if green paratroopa, turn it around
cmp #$07
bcs ExTA ;if any OTHER enemy object => $07, leave
RXSpd: lda Enemy_X_Speed,x ;load horizontal speed
eor #$ff ;get two's compliment for horizontal speed
tay
iny
sty Enemy_X_Speed,x ;store as new horizontal speed
lda Enemy_MovingDir,x
eor #%00000011 ;invert moving direction and store, then leave
sta Enemy_MovingDir,x ;thus effectively turning the enemy around
ExTA: rts ;leave!!!
;-------------------------------------------------------------------------------------
;$00 - vertical position of platform
LargePlatformCollision:
lda #$ff ;save value here
sta PlatformCollisionFlag,x
lda TimerControl ;check master timer control
bne ExLPC ;if set, branch to leave
lda Enemy_State,x ;if d7 set in object state,
bmi ExLPC ;branch to leave
lda Enemy_ID,x
cmp #$24 ;check enemy object identifier for
bne ChkForPlayerC_LargeP ;balance platform, branch if not found
lda Enemy_State,x
tax ;set state as enemy offset here
jsr ChkForPlayerC_LargeP ;perform code with state offset, then original offset, in X
ChkForPlayerC_LargeP:
jsr CheckPlayerVertical ;figure out if player is below a certain point
bcs ExLPC ;or offscreen, branch to leave if true
txa
jsr GetEnemyBoundBoxOfsArg ;get bounding box offset in Y
lda Enemy_Y_Position,x ;store vertical coordinate in
sta $00 ;temp variable for now
txa ;send offset we're on to the stack
pha
jsr PlayerCollisionCore ;do player-to-platform collision detection
pla ;retrieve offset from the stack
tax
bcc ExLPC ;if no collision, branch to leave
jsr ProcLPlatCollisions ;otherwise collision, perform sub
ExLPC: ldx ObjectOffset ;get enemy object buffer offset and leave
rts
;--------------------------------
;$00 - counter for bounding boxes
SmallPlatformCollision:
lda TimerControl ;if master timer control set,
bne ExSPC ;branch to leave
sta PlatformCollisionFlag,x ;otherwise initialize collision flag
jsr CheckPlayerVertical ;do a sub to see if player is below a certain point
bcs ExSPC ;or entirely offscreen, and branch to leave if true
lda #$02
sta $00 ;load counter here for 2 bounding boxes
ChkSmallPlatLoop:
ldx ObjectOffset ;get enemy object offset
jsr GetEnemyBoundBoxOfs ;get bounding box offset in Y
and #%00000010 ;if d1 of offscreen lower nybble bits was set
bne ExSPC ;then branch to leave
lda BoundingBox_UL_YPos,y ;check top of platform's bounding box for being
cmp #$20 ;above a specific point
bcc MoveBoundBox ;if so, branch, don't do collision detection
jsr PlayerCollisionCore ;otherwise, perform player-to-platform collision detection
bcs ProcSPlatCollisions ;skip ahead if collision
MoveBoundBox:
lda BoundingBox_UL_YPos,y ;move bounding box vertical coordinates
clc ;128 pixels downwards
adc #$80
sta BoundingBox_UL_YPos,y
lda BoundingBox_DR_YPos,y
clc
adc #$80
sta BoundingBox_DR_YPos,y
dec $00 ;decrement counter we set earlier
bne ChkSmallPlatLoop ;loop back until both bounding boxes are checked
ExSPC: ldx ObjectOffset ;get enemy object buffer offset, then leave
rts
;--------------------------------
ProcSPlatCollisions:
ldx ObjectOffset ;return enemy object buffer offset to X, then continue
ProcLPlatCollisions:
lda BoundingBox_DR_YPos,y ;get difference by subtracting the top
sec ;of the player's bounding box from the bottom
sbc BoundingBox_UL_YPos ;of the platform's bounding box
cmp #$04 ;if difference too large or negative,
bcs ChkForTopCollision ;branch, do not alter vertical speed of player
lda Player_Y_Speed ;check to see if player's vertical speed is moving down
bpl ChkForTopCollision ;if so, don't mess with it
lda #$01 ;otherwise, set vertical
sta Player_Y_Speed ;speed of player to kill jump
ChkForTopCollision:
lda BoundingBox_DR_YPos ;get difference by subtracting the top
sec ;of the platform's bounding box from the bottom
sbc BoundingBox_UL_YPos,y ;of the player's bounding box
cmp #$06
bcs PlatformSideCollisions ;if difference not close enough, skip all of this
lda Player_Y_Speed
bmi PlatformSideCollisions ;if player's vertical speed moving upwards, skip this
lda $00 ;get saved bounding box counter from earlier
ldy Enemy_ID,x
cpy #$2b ;if either of the two small platform objects are found,
beq SetCollisionFlag ;regardless of which one, branch to use bounding box counter
cpy #$2c ;as contents of collision flag
beq SetCollisionFlag
txa ;otherwise use enemy object buffer offset
SetCollisionFlag:
ldx ObjectOffset ;get enemy object buffer offset
sta PlatformCollisionFlag,x ;save either bounding box counter or enemy offset here
lda #$00
sta Player_State ;set player state to normal then leave
rts
PlatformSideCollisions:
lda #$01 ;set value here to indicate possible horizontal
sta $00 ;collision on left side of platform
lda BoundingBox_DR_XPos ;get difference by subtracting platform's left edge
sec ;from player's right edge
sbc BoundingBox_UL_XPos,y
cmp #$08 ;if difference close enough, skip all of this
bcc SideC
inc $00 ;otherwise increment value set here for right side collision
lda BoundingBox_DR_XPos,y ;get difference by subtracting player's left edge
clc ;from platform's right edge
sbc BoundingBox_UL_XPos
cmp #$09 ;if difference not close enough, skip subroutine
bcs NoSideC ;and instead branch to leave (no collision)
SideC: jsr ImpedePlayerMove ;deal with horizontal collision
NoSideC: ldx ObjectOffset ;return with enemy object buffer offset
rts
;-------------------------------------------------------------------------------------
PlayerPosSPlatData:
.db $80, $00
PositionPlayerOnS_Plat:
tay ;use bounding box counter saved in collision flag
lda Enemy_Y_Position,x ;for offset
clc ;add positioning data using offset to the vertical
adc PlayerPosSPlatData-1,y ;coordinate
.db $2c ;BIT instruction opcode
PositionPlayerOnVPlat:
lda Enemy_Y_Position,x ;get vertical coordinate
ldy GameEngineSubroutine
cpy #$0b ;if certain routine being executed on this frame,
beq ExPlPos ;skip all of this
ldy Enemy_Y_HighPos,x
cpy #$01 ;if vertical high byte offscreen, skip this
bne ExPlPos
sec ;subtract 32 pixels from vertical coordinate
sbc #$20 ;for the player object's height
sta Player_Y_Position ;save as player's new vertical coordinate
tya
sbc #$00 ;subtract borrow and store as player's
sta Player_Y_HighPos ;new vertical high byte
lda #$00
sta Player_Y_Speed ;initialize vertical speed and low byte of force
sta Player_Y_MoveForce ;and then leave
ExPlPos: rts
;-------------------------------------------------------------------------------------
CheckPlayerVertical:
lda Player_OffscreenBits ;if player object is completely offscreen
cmp #$f0 ;vertically, leave this routine
bcs ExCPV
ldy Player_Y_HighPos ;if player high vertical byte is not
dey ;within the screen, leave this routine
bne ExCPV
lda Player_Y_Position ;if on the screen, check to see how far down
cmp #$d0 ;the player is vertically
ExCPV: rts
;-------------------------------------------------------------------------------------
GetEnemyBoundBoxOfs:
lda ObjectOffset ;get enemy object buffer offset
GetEnemyBoundBoxOfsArg:
asl ;multiply A by four, then add four
asl ;to skip player's bounding box
clc
adc #$04
tay ;send to Y
lda Enemy_OffscreenBits ;get offscreen bits for enemy object
and #%00001111 ;save low nybble
cmp #%00001111 ;check for all bits set
rts
;-------------------------------------------------------------------------------------
;$00-$01 - used to hold many values, essentially temp variables
;$04 - holds lower nybble of vertical coordinate from block buffer routine
;$eb - used to hold block buffer adder
PlayerBGUpperExtent:
.db $20, $10
PlayerBGCollision:
lda DisableCollisionDet ;if collision detection disabled flag set,
bne ExPBGCol ;branch to leave
lda GameEngineSubroutine
cmp #$0b ;if running routine #11 or $0b
beq ExPBGCol ;branch to leave
cmp #$04
bcc ExPBGCol ;if running routines $00-$03 branch to leave
lda #$01 ;load default player state for swimming
ldy SwimmingFlag ;if swimming flag set,
bne SetPSte ;branch ahead to set default state
lda Player_State ;if player in normal state,
beq SetFallS ;branch to set default state for falling
cmp #$03
bne ChkOnScr ;if in any other state besides climbing, skip to next part
SetFallS: lda #$02 ;load default player state for falling
SetPSte: sta Player_State ;set whatever player state is appropriate
ChkOnScr: lda Player_Y_HighPos
cmp #$01 ;check player's vertical high byte for still on the screen
bne ExPBGCol ;branch to leave if not
lda #$ff
sta Player_CollisionBits ;initialize player's collision flag
lda Player_Y_Position
cmp #$cf ;check player's vertical coordinate
bcc ChkCollSize ;if not too close to the bottom of screen, continue
ExPBGCol: rts ;otherwise leave
ChkCollSize:
ldy #$02 ;load default offset
lda CrouchingFlag
bne GBBAdr ;if player crouching, skip ahead
lda PlayerSize
bne GBBAdr ;if player small, skip ahead
dey ;otherwise decrement offset for big player not crouching
lda SwimmingFlag
bne GBBAdr ;if swimming flag set, skip ahead
dey ;otherwise decrement offset
GBBAdr: lda BlockBufferAdderData,y ;get value using offset
sta $eb ;store value here
tay ;put value into Y, as offset for block buffer routine
ldx PlayerSize ;get player's size as offset
lda CrouchingFlag
beq HeadChk ;if player not crouching, branch ahead
inx ;otherwise increment size as offset
HeadChk: lda Player_Y_Position ;get player's vertical coordinate
cmp PlayerBGUpperExtent,x ;compare with upper extent value based on offset
bcc DoFootCheck ;if player is too high, skip this part
jsr BlockBufferColli_Head ;do player-to-bg collision detection on top of
beq DoFootCheck ;player, and branch if nothing above player's head
jsr CheckForCoinMTiles ;check to see if player touched coin with their head
bcs AwardTouchedCoin ;if so, branch to some other part of code
ldy Player_Y_Speed ;check player's vertical speed
bpl DoFootCheck ;if player not moving upwards, branch elsewhere
ldy $04 ;check lower nybble of vertical coordinate returned
cpy #$04 ;from collision detection routine
bcc DoFootCheck ;if low nybble < 4, branch
jsr CheckForSolidMTiles ;check to see what player's head bumped on
bcs SolidOrClimb ;if player collided with solid metatile, branch
ldy AreaType ;otherwise check area type
beq NYSpd ;if water level, branch ahead
ldy BlockBounceTimer ;if block bounce timer not expired,
bne NYSpd ;branch ahead, do not process collision
jsr PlayerHeadCollision ;otherwise do a sub to process collision
jmp DoFootCheck ;jump ahead to skip these other parts here
SolidOrClimb:
cmp #$26 ;if climbing metatile,
beq NYSpd ;branch ahead and do not play sound
lda #Sfx_Bump
sta Square1SoundQueue ;otherwise load bump sound
NYSpd: lda #$01 ;set player's vertical speed to nullify
sta Player_Y_Speed ;jump or swim
DoFootCheck:
ldy $eb ;get block buffer adder offset
lda Player_Y_Position
cmp #$cf ;check to see how low player is
bcs DoPlayerSideCheck ;if player is too far down on screen, skip all of this
jsr BlockBufferColli_Feet ;do player-to-bg collision detection on bottom left of player
jsr CheckForCoinMTiles ;check to see if player touched coin with their left foot
bcs AwardTouchedCoin ;if so, branch to some other part of code
pha ;save bottom left metatile to stack
jsr BlockBufferColli_Feet ;do player-to-bg collision detection on bottom right of player
sta $00 ;save bottom right metatile here
pla
sta $01 ;pull bottom left metatile and save here
bne ChkFootMTile ;if anything here, skip this part
lda $00 ;otherwise check for anything in bottom right metatile
beq DoPlayerSideCheck ;and skip ahead if not
jsr CheckForCoinMTiles ;check to see if player touched coin with their right foot
bcc ChkFootMTile ;if not, skip unconditional jump and continue code
AwardTouchedCoin:
jmp HandleCoinMetatile ;follow the code to erase coin and award to player 1 coin
ChkFootMTile:
jsr CheckForClimbMTiles ;check to see if player landed on climbable metatiles
bcs DoPlayerSideCheck ;if so, branch
ldy Player_Y_Speed ;check player's vertical speed
bmi DoPlayerSideCheck ;if player moving upwards, branch
cmp #$c5
bne ContChk ;if player did not touch axe, skip ahead
jmp HandleAxeMetatile ;otherwise jump to set modes of operation
ContChk: jsr ChkInvisibleMTiles ;do sub to check for hidden coin or 1-up blocks
beq DoPlayerSideCheck ;if either found, branch
ldy JumpspringAnimCtrl ;if jumpspring animating right now,
bne InitSteP ;branch ahead
ldy $04 ;check lower nybble of vertical coordinate returned
cpy #$05 ;from collision detection routine
bcc LandPlyr ;if lower nybble < 5, branch
lda Player_MovingDir
sta $00 ;use player's moving direction as temp variable
jmp ImpedePlayerMove ;jump to impede player's movement in that direction
LandPlyr: jsr ChkForLandJumpSpring ;do sub to check for jumpspring metatiles and deal with it
lda #$f0
and Player_Y_Position ;mask out lower nybble of player's vertical position
sta Player_Y_Position ;and store as new vertical position to land player properly
jsr HandlePipeEntry ;do sub to process potential pipe entry
lda #$00
sta Player_Y_Speed ;initialize vertical speed and fractional
sta Player_Y_MoveForce ;movement force to stop player's vertical movement
sta StompChainCounter ;initialize enemy stomp counter
InitSteP: lda #$00
sta Player_State ;set player's state to normal
DoPlayerSideCheck:
ldy $eb ;get block buffer adder offset
iny
iny ;increment offset 2 bytes to use adders for side collisions
lda #$02 ;set value here to be used as counter
sta $00
SideCheckLoop:
iny ;move onto the next one
sty $eb ;store it
lda Player_Y_Position
cmp #$20 ;check player's vertical position
bcc BHalf ;if player is in status bar area, branch ahead to skip this part
cmp #$e4
bcs ExSCH ;branch to leave if player is too far down
jsr BlockBufferColli_Side ;do player-to-bg collision detection on one half of player
beq BHalf ;branch ahead if nothing found
cmp #$1c ;otherwise check for pipe metatiles
beq BHalf ;if collided with sideways pipe (top), branch ahead
cmp #$6b
beq BHalf ;if collided with water pipe (top), branch ahead
jsr CheckForClimbMTiles ;do sub to see if player bumped into anything climbable
bcc CheckSideMTiles ;if not, branch to alternate section of code
BHalf: ldy $eb ;load block adder offset
iny ;increment it
lda Player_Y_Position ;get player's vertical position
cmp #$08
bcc ExSCH ;if too high, branch to leave
cmp #$d0
bcs ExSCH ;if too low, branch to leave
jsr BlockBufferColli_Side ;do player-to-bg collision detection on other half of player
bne CheckSideMTiles ;if something found, branch
dec $00 ;otherwise decrement counter
bne SideCheckLoop ;run code until both sides of player are checked
ExSCH: rts ;leave
CheckSideMTiles:
jsr ChkInvisibleMTiles ;check for hidden or coin 1-up blocks
beq ExCSM ;branch to leave if either found
jsr CheckForClimbMTiles ;check for climbable metatiles
bcc ContSChk ;if not found, skip and continue with code
jmp HandleClimbing ;otherwise jump to handle climbing
ContSChk: jsr CheckForCoinMTiles ;check to see if player touched coin
bcs HandleCoinMetatile ;if so, execute code to erase coin and award to player 1 coin
jsr ChkJumpspringMetatiles ;check for jumpspring metatiles
bcc ChkPBtm ;if not found, branch ahead to continue cude
lda JumpspringAnimCtrl ;otherwise check jumpspring animation control
bne ExCSM ;branch to leave if set
jmp StopPlayerMove ;otherwise jump to impede player's movement
ChkPBtm: ldy Player_State ;get player's state
cpy #$00 ;check for player's state set to normal
bne StopPlayerMove ;if not, branch to impede player's movement
ldy PlayerFacingDir ;get player's facing direction
dey
bne StopPlayerMove ;if facing left, branch to impede movement
cmp #$6c ;otherwise check for pipe metatiles
beq PipeDwnS ;if collided with sideways pipe (bottom), branch
cmp #$1f ;if collided with water pipe (bottom), continue
bne StopPlayerMove ;otherwise branch to impede player's movement
PipeDwnS: lda Player_SprAttrib ;check player's attributes
bne PlyrPipe ;if already set, branch, do not play sound again
ldy #Sfx_PipeDown_Injury
sty Square1SoundQueue ;otherwise load pipedown/injury sound
PlyrPipe: ora #%00100000
sta Player_SprAttrib ;set background priority bit in player attributes
lda Player_X_Position
and #%00001111 ;get lower nybble of player's horizontal coordinate
beq ChkGERtn ;if at zero, branch ahead to skip this part
ldy #$00 ;set default offset for timer setting data
lda ScreenLeft_PageLoc ;load page location for left side of screen
beq SetCATmr ;if at page zero, use default offset
iny ;otherwise increment offset
SetCATmr: lda AreaChangeTimerData,y ;set timer for change of area as appropriate
sta ChangeAreaTimer
ChkGERtn: lda GameEngineSubroutine ;get number of game engine routine running
cmp #$07
beq ExCSM ;if running player entrance routine or
cmp #$08 ;player control routine, go ahead and branch to leave
bne ExCSM
lda #$02
sta GameEngineSubroutine ;otherwise set sideways pipe entry routine to run
rts ;and leave
;--------------------------------
;$02 - high nybble of vertical coordinate from block buffer
;$04 - low nybble of horizontal coordinate from block buffer
;$06-$07 - block buffer address
StopPlayerMove:
jsr ImpedePlayerMove ;stop player's movement
ExCSM: rts ;leave
AreaChangeTimerData:
.db $a0, $34
HandleCoinMetatile:
jsr ErACM ;do sub to erase coin metatile from block buffer
inc CoinTallyFor1Ups ;increment coin tally used for 1-up blocks
jmp GiveOneCoin ;update coin amount and tally on the screen
HandleAxeMetatile:
lda #$00
sta OperMode_Task ;reset secondary mode
lda #$02
sta OperMode ;set primary mode to autoctrl mode
lda #$18
sta Player_X_Speed ;set horizontal speed and continue to erase axe metatile
ErACM: ldy $02 ;load vertical high nybble offset for block buffer
lda #$00 ;load blank metatile
sta ($06),y ;store to remove old contents from block buffer
jmp RemoveCoin_Axe ;update the screen accordingly
;--------------------------------
;$02 - high nybble of vertical coordinate from block buffer
;$04 - low nybble of horizontal coordinate from block buffer
;$06-$07 - block buffer address
ClimbXPosAdder:
.db $f9, $07
ClimbPLocAdder:
.db $ff, $00
FlagpoleYPosData:
.db $18, $22, $50, $68, $90
HandleClimbing:
ldy $04 ;check low nybble of horizontal coordinate returned from
cpy #$06 ;collision detection routine against certain values, this
bcc ExHC ;makes actual physical part of vine or flagpole thinner
cpy #$0a ;than 16 pixels
bcc ChkForFlagpole
ExHC: rts ;leave if too far left or too far right
ChkForFlagpole:
cmp #$24 ;check climbing metatiles
beq FlagpoleCollision ;branch if flagpole ball found
cmp #$25
bne VineCollision ;branch to alternate code if flagpole shaft not found
FlagpoleCollision:
lda GameEngineSubroutine
cmp #$05 ;check for end-of-level routine running
beq PutPlayerOnVine ;if running, branch to end of climbing code
lda #$01
sta PlayerFacingDir ;set player's facing direction to right
inc ScrollLock ;set scroll lock flag
lda GameEngineSubroutine
cmp #$04 ;check for flagpole slide routine running
beq RunFR ;if running, branch to end of flagpole code here
lda #BulletBill_CannonVar ;load identifier for bullet bills (cannon variant)
jsr KillEnemies ;get rid of them
lda #Silence
sta EventMusicQueue ;silence music
lsr
sta FlagpoleSoundQueue ;load flagpole sound into flagpole sound queue
ldx #$04 ;start at end of vertical coordinate data
lda Player_Y_Position
sta FlagpoleCollisionYPos ;store player's vertical coordinate here to be used later
ChkFlagpoleYPosLoop:
cmp FlagpoleYPosData,x ;compare with current vertical coordinate data
bcs MtchF ;if player's => current, branch to use current offset
dex ;otherwise decrement offset to use
bne ChkFlagpoleYPosLoop ;do this until all data is checked (use last one if all checked)
MtchF: stx FlagpoleScore ;store offset here to be used later
RunFR: lda #$04
sta GameEngineSubroutine ;set value to run flagpole slide routine
jmp PutPlayerOnVine ;jump to end of climbing code
VineCollision:
cmp #$26 ;check for climbing metatile used on vines
bne PutPlayerOnVine
lda Player_Y_Position ;check player's vertical coordinate
cmp #$20 ;for being in status bar area
bcs PutPlayerOnVine ;branch if not that far up
lda #$01
sta GameEngineSubroutine ;otherwise set to run autoclimb routine next frame
PutPlayerOnVine:
lda #$03 ;set player state to climbing
sta Player_State
lda #$00 ;nullify player's horizontal speed
sta Player_X_Speed ;and fractional horizontal movement force
sta Player_X_MoveForce
lda Player_X_Position ;get player's horizontal coordinate
sec
sbc ScreenLeft_X_Pos ;subtract from left side horizontal coordinate
cmp #$10
bcs SetVXPl ;if 16 or more pixels difference, do not alter facing direction
lda #$02
sta PlayerFacingDir ;otherwise force player to face left
SetVXPl: ldy PlayerFacingDir ;get current facing direction, use as offset
lda $06 ;get low byte of block buffer address
asl
asl ;move low nybble to high
asl
asl
clc
adc ClimbXPosAdder-1,y ;add pixels depending on facing direction
sta Player_X_Position ;store as player's horizontal coordinate
lda $06 ;get low byte of block buffer address again
bne ExPVne ;if not zero, branch
lda ScreenRight_PageLoc ;load page location of right side of screen
clc
adc ClimbPLocAdder-1,y ;add depending on facing location
sta Player_PageLoc ;store as player's page location
ExPVne: rts ;finally, we're done!
;--------------------------------
ChkInvisibleMTiles:
cmp #$5f ;check for hidden coin block
beq ExCInvT ;branch to leave if found
cmp #$60 ;check for hidden 1-up block
ExCInvT: rts ;leave with zero flag set if either found
;--------------------------------
;$00-$01 - used to hold bottom right and bottom left metatiles (in that order)
;$00 - used as flag by ImpedePlayerMove to restrict specific movement
ChkForLandJumpSpring:
jsr ChkJumpspringMetatiles ;do sub to check if player landed on jumpspring
bcc ExCJSp ;if carry not set, jumpspring not found, therefore leave
lda #$70
sta VerticalForce ;otherwise set vertical movement force for player
lda #$f9
sta JumpspringForce ;set default jumpspring force
lda #$03
sta JumpspringTimer ;set jumpspring timer to be used later
lsr
sta JumpspringAnimCtrl ;set jumpspring animation control to start animating
ExCJSp: rts ;and leave
ChkJumpspringMetatiles:
cmp #$67 ;check for top jumpspring metatile
beq JSFnd ;branch to set carry if found
cmp #$68 ;check for bottom jumpspring metatile
clc ;clear carry flag
bne NoJSFnd ;branch to use cleared carry if not found
JSFnd: sec ;set carry if found
NoJSFnd: rts ;leave
HandlePipeEntry:
lda Up_Down_Buttons ;check saved controller bits from earlier
and #%00000100 ;for pressing down
beq ExPipeE ;if not pressing down, branch to leave
lda $00
cmp #$11 ;check right foot metatile for warp pipe right metatile
bne ExPipeE ;branch to leave if not found
lda $01
cmp #$10 ;check left foot metatile for warp pipe left metatile
bne ExPipeE ;branch to leave if not found
lda #$30
sta ChangeAreaTimer ;set timer for change of area
lda #$03
sta GameEngineSubroutine ;set to run vertical pipe entry routine on next frame
lda #Sfx_PipeDown_Injury
sta Square1SoundQueue ;load pipedown/injury sound
lda #%00100000
sta Player_SprAttrib ;set background priority bit in player's attributes
lda WarpZoneControl ;check warp zone control
beq ExPipeE ;branch to leave if none found
and #%00000011 ;mask out all but 2 LSB
asl
asl ;multiply by four
tax ;save as offset to warp zone numbers (starts at left pipe)
lda Player_X_Position ;get player's horizontal position
cmp #$60
bcc GetWNum ;if player at left, not near middle, use offset and skip ahead
inx ;otherwise increment for middle pipe
cmp #$a0
bcc GetWNum ;if player at middle, but not too far right, use offset and skip
inx ;otherwise increment for last pipe
GetWNum: ldy WarpZoneNumbers,x ;get warp zone numbers
dey ;decrement for use as world number
sty WorldNumber ;store as world number and offset
ldx WorldAddrOffsets,y ;get offset to where this world's area offsets are
lda AreaAddrOffsets,x ;get area offset based on world offset
sta AreaPointer ;store area offset here to be used to change areas
lda #Silence
sta EventMusicQueue ;silence music
lda #$00
sta EntrancePage ;initialize starting page number
sta AreaNumber ;initialize area number used for area address offset
sta LevelNumber ;initialize level number used for world display
sta AltEntranceControl ;initialize mode of entry
inc Hidden1UpFlag ;set flag for hidden 1-up blocks
inc FetchNewGameTimerFlag ;set flag to load new game timer
ExPipeE: rts ;leave!!!
ImpedePlayerMove:
lda #$00 ;initialize value here
ldy Player_X_Speed ;get player's horizontal speed
ldx $00 ;check value set earlier for
dex ;left side collision
bne RImpd ;if right side collision, skip this part
inx ;return value to X
cpy #$00 ;if player moving to the left,
bmi ExIPM ;branch to invert bit and leave
lda #$ff ;otherwise load A with value to be used later
jmp NXSpd ;and jump to affect movement
RImpd: ldx #$02 ;return $02 to X
cpy #$01 ;if player moving to the right,
bpl ExIPM ;branch to invert bit and leave
lda #$01 ;otherwise load A with value to be used here
NXSpd: ldy #$10
sty SideCollisionTimer ;set timer of some sort
ldy #$00
sty Player_X_Speed ;nullify player's horizontal speed
cmp #$00 ;if value set in A not set to $ff,
bpl PlatF ;branch ahead, do not decrement Y
dey ;otherwise decrement Y now
PlatF: sty $00 ;store Y as high bits of horizontal adder
clc
adc Player_X_Position ;add contents of A to player's horizontal
sta Player_X_Position ;position to move player left or right
lda Player_PageLoc
adc $00 ;add high bits and carry to
sta Player_PageLoc ;page location if necessary
ExIPM: txa ;invert contents of X
eor #$ff
and Player_CollisionBits ;mask out bit that was set here
sta Player_CollisionBits ;store to clear bit
rts
;--------------------------------
SolidMTileUpperExt:
.db $10, $61, $88, $c4
CheckForSolidMTiles:
jsr GetMTileAttrib ;find appropriate offset based on metatile's 2 MSB
cmp SolidMTileUpperExt,x ;compare current metatile with solid metatiles
rts
ClimbMTileUpperExt:
.db $24, $6d, $8a, $c6
CheckForClimbMTiles:
jsr GetMTileAttrib ;find appropriate offset based on metatile's 2 MSB
cmp ClimbMTileUpperExt,x ;compare current metatile with climbable metatiles
rts
CheckForCoinMTiles:
cmp #$c2 ;check for regular coin
beq CoinSd ;branch if found
cmp #$c3 ;check for underwater coin
beq CoinSd ;branch if found
clc ;otherwise clear carry and leave
rts
CoinSd: lda #Sfx_CoinGrab
sta Square2SoundQueue ;load coin grab sound and leave
rts
GetMTileAttrib:
tay ;save metatile value into Y
and #%11000000 ;mask out all but 2 MSB
asl
rol ;shift and rotate d7-d6 to d1-d0
rol
tax ;use as offset for metatile data
tya ;get original metatile value back
ExEBG: rts ;leave
;-------------------------------------------------------------------------------------
;$06-$07 - address from block buffer routine
EnemyBGCStateData:
.db $01, $01, $02, $02, $02, $05
EnemyBGCXSpdData:
.db $10, $f0
EnemyToBGCollisionDet:
lda Enemy_State,x ;check enemy state for d6 set
and #%00100000
bne ExEBG ;if set, branch to leave
jsr SubtEnemyYPos ;otherwise, do a subroutine here
bcc ExEBG ;if enemy vertical coord + 62 < 68, branch to leave
ldy Enemy_ID,x
cpy #Spiny ;if enemy object is not spiny, branch elsewhere
bne DoIDCheckBGColl
lda Enemy_Y_Position,x
cmp #$25 ;if enemy vertical coordinate < 36 branch to leave
bcc ExEBG
DoIDCheckBGColl:
cpy #GreenParatroopaJump ;check for some other enemy object
bne HBChk ;branch if not found
jmp EnemyJump ;otherwise jump elsewhere
HBChk: cpy #HammerBro ;check for hammer bro
bne CInvu ;branch if not found
jmp HammerBroBGColl ;otherwise jump elsewhere
CInvu: cpy #Spiny ;if enemy object is spiny, branch
beq YesIn
cpy #PowerUpObject ;if special power-up object, branch
beq YesIn
cpy #$07 ;if enemy object =>$07, branch to leave
bcs ExEBGChk
YesIn: jsr ChkUnderEnemy ;if enemy object < $07, or = $12 or $2e, do this sub
bne HandleEToBGCollision ;if block underneath enemy, branch
NoEToBGCollision:
jmp ChkForRedKoopa ;otherwise skip and do something else
;--------------------------------
;$02 - vertical coordinate from block buffer routine
HandleEToBGCollision:
jsr ChkForNonSolids ;if something is underneath enemy, find out what
beq NoEToBGCollision ;if blank $26, coins, or hidden blocks, jump, enemy falls through
cmp #$23
bne LandEnemyProperly ;check for blank metatile $23 and branch if not found
ldy $02 ;get vertical coordinate used to find block
lda #$00 ;store default blank metatile in that spot so we won't
sta ($06),y ;trigger this routine accidentally again
lda Enemy_ID,x
cmp #$15 ;if enemy object => $15, branch ahead
bcs ChkToStunEnemies
cmp #Goomba ;if enemy object not goomba, branch ahead of this routine
bne GiveOEPoints
jsr KillEnemyAboveBlock ;if enemy object IS goomba, do this sub
GiveOEPoints:
lda #$01 ;award 100 points for hitting block beneath enemy
jsr SetupFloateyNumber
ChkToStunEnemies:
cmp #$09 ;perform many comparisons on enemy object identifier
bcc SetStun
cmp #$11 ;if the enemy object identifier is equal to the values
bcs SetStun ;$09, $0e, $0f or $10, it will be modified, and not
cmp #$0a ;modified if not any of those values, note that piranha plant will
bcc Demote ;always fail this test because A will still have vertical
cmp #PiranhaPlant ;coordinate from previous addition, also these comparisons
bcc SetStun ;are only necessary if branching from $d7a1
Demote: and #%00000001 ;erase all but LSB, essentially turning enemy object
sta Enemy_ID,x ;into green or red koopa troopa to demote them
SetStun: lda Enemy_State,x ;load enemy state
and #%11110000 ;save high nybble
ora #%00000010
sta Enemy_State,x ;set d1 of enemy state
dec Enemy_Y_Position,x
dec Enemy_Y_Position,x ;subtract two pixels from enemy's vertical position
lda Enemy_ID,x
cmp #Bloober ;check for bloober object
beq SetWYSpd
lda #$fd ;set default vertical speed
ldy AreaType
bne SetNotW ;if area type not water, set as speed, otherwise
SetWYSpd: lda #$ff ;change the vertical speed
SetNotW: sta Enemy_Y_Speed,x ;set vertical speed now
ldy #$01
jsr PlayerEnemyDiff ;get horizontal difference between player and enemy object
bpl ChkBBill ;branch if enemy is to the right of player
iny ;increment Y if not
ChkBBill: lda Enemy_ID,x
cmp #BulletBill_CannonVar ;check for bullet bill (cannon variant)
beq NoCDirF
cmp #BulletBill_FrenzyVar ;check for bullet bill (frenzy variant)
beq NoCDirF ;branch if either found, direction does not change
sty Enemy_MovingDir,x ;store as moving direction
NoCDirF: dey ;decrement and use as offset
lda EnemyBGCXSpdData,y ;get proper horizontal speed
sta Enemy_X_Speed,x ;and store, then leave
ExEBGChk: rts
;--------------------------------
;$04 - low nybble of vertical coordinate from block buffer routine
LandEnemyProperly:
lda $04 ;check lower nybble of vertical coordinate saved earlier
sec
sbc #$08 ;subtract eight pixels
cmp #$05 ;used to determine whether enemy landed from falling
bcs ChkForRedKoopa ;branch if lower nybble in range of $0d-$0f before subtract
lda Enemy_State,x
and #%01000000 ;branch if d6 in enemy state is set
bne LandEnemyInitState
lda Enemy_State,x
asl ;branch if d7 in enemy state is not set
bcc ChkLandedEnemyState
SChkA: jmp DoEnemySideCheck ;if lower nybble < $0d, d7 set but d6 not set, jump here
ChkLandedEnemyState:
lda Enemy_State,x ;if enemy in normal state, branch back to jump here
beq SChkA
cmp #$05 ;if in state used by spiny's egg
beq ProcEnemyDirection ;then branch elsewhere
cmp #$03 ;if already in state used by koopas and buzzy beetles
bcs ExSteChk ;or in higher numbered state, branch to leave
lda Enemy_State,x ;load enemy state again (why?)
cmp #$02 ;if not in $02 state (used by koopas and buzzy beetles)
bne ProcEnemyDirection ;then branch elsewhere
lda #$10 ;load default timer here
ldy Enemy_ID,x ;check enemy identifier for spiny
cpy #Spiny
bne SetForStn ;branch if not found
lda #$00 ;set timer for $00 if spiny
SetForStn: sta EnemyIntervalTimer,x ;set timer here
lda #$03 ;set state here, apparently used to render
sta Enemy_State,x ;upside-down koopas and buzzy beetles
jsr EnemyLanding ;then land it properly
ExSteChk: rts ;then leave
ProcEnemyDirection:
lda Enemy_ID,x ;check enemy identifier for goomba
cmp #Goomba ;branch if found
beq LandEnemyInitState
cmp #Spiny ;check for spiny
bne InvtD ;branch if not found
lda #$01
sta Enemy_MovingDir,x ;send enemy moving to the right by default
lda #$08
sta Enemy_X_Speed,x ;set horizontal speed accordingly
lda FrameCounter
and #%00000111 ;if timed appropriately, spiny will skip over
beq LandEnemyInitState ;trying to face the player
InvtD: ldy #$01 ;load 1 for enemy to face the left (inverted here)
jsr PlayerEnemyDiff ;get horizontal difference between player and enemy
bpl CNwCDir ;if enemy to the right of player, branch
iny ;if to the left, increment by one for enemy to face right (inverted)
CNwCDir: tya
cmp Enemy_MovingDir,x ;compare direction in A with current direction in memory
bne LandEnemyInitState
jsr ChkForBump_HammerBroJ ;if equal, not facing in correct dir, do sub to turn around
LandEnemyInitState:
jsr EnemyLanding ;land enemy properly
lda Enemy_State,x
and #%10000000 ;if d7 of enemy state is set, branch
bne NMovShellFallBit
lda #$00 ;otherwise initialize enemy state and leave
sta Enemy_State,x ;note this will also turn spiny's egg into spiny
rts
NMovShellFallBit:
lda Enemy_State,x ;nullify d6 of enemy state, save other bits
and #%10111111 ;and store, then leave
sta Enemy_State,x
rts
;--------------------------------
ChkForRedKoopa:
lda Enemy_ID,x ;check for red koopa troopa $03
cmp #RedKoopa
bne Chk2MSBSt ;branch if not found
lda Enemy_State,x
beq ChkForBump_HammerBroJ ;if enemy found and in normal state, branch
Chk2MSBSt: lda Enemy_State,x ;save enemy state into Y
tay
asl ;check for d7 set
bcc GetSteFromD ;branch if not set
lda Enemy_State,x
ora #%01000000 ;set d6
jmp SetD6Ste ;jump ahead of this part
GetSteFromD: lda EnemyBGCStateData,y ;load new enemy state with old as offset
SetD6Ste: sta Enemy_State,x ;set as new state
;--------------------------------
;$00 - used to store bitmask (not used but initialized here)
;$eb - used in DoEnemySideCheck as counter and to compare moving directions
DoEnemySideCheck:
lda Enemy_Y_Position,x ;if enemy within status bar, branch to leave
cmp #$20 ;because there's nothing there that impedes movement
bcc ExESdeC
ldy #$16 ;start by finding block to the left of enemy ($00,$14)
lda #$02 ;set value here in what is also used as
sta $eb ;OAM data offset
SdeCLoop: lda $eb ;check value
cmp Enemy_MovingDir,x ;compare value against moving direction
bne NextSdeC ;branch if different and do not seek block there
lda #$01 ;set flag in A for save horizontal coordinate
jsr BlockBufferChk_Enemy ;find block to left or right of enemy object
beq NextSdeC ;if nothing found, branch
jsr ChkForNonSolids ;check for non-solid blocks
bne ChkForBump_HammerBroJ ;branch if not found
NextSdeC: dec $eb ;move to the next direction
iny
cpy #$18 ;increment Y, loop only if Y < $18, thus we check
bcc SdeCLoop ;enemy ($00, $14) and ($10, $14) pixel coordinates
ExESdeC: rts
ChkForBump_HammerBroJ:
cpx #$05 ;check if we're on the special use slot
beq NoBump ;and if so, branch ahead and do not play sound
lda Enemy_State,x ;if enemy state d7 not set, branch
asl ;ahead and do not play sound
bcc NoBump
lda #Sfx_Bump ;otherwise, play bump sound
sta Square1SoundQueue ;sound will never be played if branching from ChkForRedKoopa
NoBump: lda Enemy_ID,x ;check for hammer bro
cmp #$05
bne InvEnemyDir ;branch if not found
lda #$00
sta $00 ;initialize value here for bitmask
ldy #$fa ;load default vertical speed for jumping
jmp SetHJ ;jump to code that makes hammer bro jump
InvEnemyDir:
jmp RXSpd ;jump to turn the enemy around
;--------------------------------
;$00 - used to hold horizontal difference between player and enemy
PlayerEnemyDiff:
lda Enemy_X_Position,x ;get distance between enemy object's
sec ;horizontal coordinate and the player's
sbc Player_X_Position ;horizontal coordinate
sta $00 ;and store here
lda Enemy_PageLoc,x
sbc Player_PageLoc ;subtract borrow, then leave
rts
;--------------------------------
EnemyLanding:
jsr InitVStf ;do something here to vertical speed and something else
lda Enemy_Y_Position,x
and #%11110000 ;save high nybble of vertical coordinate, and
ora #%00001000 ;set d3, then store, probably used to set enemy object
sta Enemy_Y_Position,x ;neatly on whatever it's landing on
rts
SubtEnemyYPos:
lda Enemy_Y_Position,x ;add 62 pixels to enemy object's
clc ;vertical coordinate
adc #$3e
cmp #$44 ;compare against a certain range
rts ;and leave with flags set for conditional branch
EnemyJump:
jsr SubtEnemyYPos ;do a sub here
bcc DoSide ;if enemy vertical coord + 62 < 68, branch to leave
lda Enemy_Y_Speed,x
clc ;add two to vertical speed
adc #$02
cmp #$03 ;if green paratroopa not falling, branch ahead
bcc DoSide
jsr ChkUnderEnemy ;otherwise, check to see if green paratroopa is
beq DoSide ;standing on anything, then branch to same place if not
jsr ChkForNonSolids ;check for non-solid blocks
beq DoSide ;branch if found
jsr EnemyLanding ;change vertical coordinate and speed
lda #$fd
sta Enemy_Y_Speed,x ;make the paratroopa jump again
DoSide: jmp DoEnemySideCheck ;check for horizontal blockage, then leave
;--------------------------------
HammerBroBGColl:
jsr ChkUnderEnemy ;check to see if hammer bro is standing on anything
beq NoUnderHammerBro
cmp #$23 ;check for blank metatile $23 and branch if not found
bne UnderHammerBro
KillEnemyAboveBlock:
jsr ShellOrBlockDefeat ;do this sub to kill enemy
lda #$fc ;alter vertical speed of enemy and leave
sta Enemy_Y_Speed,x
rts
UnderHammerBro:
lda EnemyFrameTimer,x ;check timer used by hammer bro
bne NoUnderHammerBro ;branch if not expired
lda Enemy_State,x
and #%10001000 ;save d7 and d3 from enemy state, nullify other bits
sta Enemy_State,x ;and store
jsr EnemyLanding ;modify vertical coordinate, speed and something else
jmp DoEnemySideCheck ;then check for horizontal blockage and leave
NoUnderHammerBro:
lda Enemy_State,x ;if hammer bro is not standing on anything, set d0
ora #$01 ;in the enemy state to indicate jumping or falling, then leave
sta Enemy_State,x
rts
ChkUnderEnemy:
lda #$00 ;set flag in A for save vertical coordinate
ldy #$15 ;set Y to check the bottom middle (8,18) of enemy object
jmp BlockBufferChk_Enemy ;hop to it!
ChkForNonSolids:
cmp #$26 ;blank metatile used for vines?
beq NSFnd
cmp #$c2 ;regular coin?
beq NSFnd
cmp #$c3 ;underwater coin?
beq NSFnd
cmp #$5f ;hidden coin block?
beq NSFnd
cmp #$60 ;hidden 1-up block?
NSFnd: rts
;-------------------------------------------------------------------------------------
FireballBGCollision:
lda Fireball_Y_Position,x ;check fireball's vertical coordinate
cmp #$18
bcc ClearBounceFlag ;if within the status bar area of the screen, branch ahead
jsr BlockBufferChk_FBall ;do fireball to background collision detection on bottom of it
beq ClearBounceFlag ;if nothing underneath fireball, branch
jsr ChkForNonSolids ;check for non-solid metatiles
beq ClearBounceFlag ;branch if any found
lda Fireball_Y_Speed,x ;if fireball's vertical speed set to move upwards,
bmi InitFireballExplode ;branch to set exploding bit in fireball's state
lda FireballBouncingFlag,x ;if bouncing flag already set,
bne InitFireballExplode ;branch to set exploding bit in fireball's state
lda #$fd
sta Fireball_Y_Speed,x ;otherwise set vertical speed to move upwards (give it bounce)
lda #$01
sta FireballBouncingFlag,x ;set bouncing flag
lda Fireball_Y_Position,x
and #$f8 ;modify vertical coordinate to land it properly
sta Fireball_Y_Position,x ;store as new vertical coordinate
rts ;leave
ClearBounceFlag:
lda #$00
sta FireballBouncingFlag,x ;clear bouncing flag by default
rts ;leave
InitFireballExplode:
lda #$80
sta Fireball_State,x ;set exploding flag in fireball's state
lda #Sfx_Bump
sta Square1SoundQueue ;load bump sound
rts ;leave
;-------------------------------------------------------------------------------------
;$00 - used to hold one of bitmasks, or offset
;$01 - used for relative X coordinate, also used to store middle screen page location
;$02 - used for relative Y coordinate, also used to store middle screen coordinate
;this data added to relative coordinates of sprite objects
;stored in order: left edge, top edge, right edge, bottom edge
BoundBoxCtrlData:
.db $02, $08, $0e, $20
.db $03, $14, $0d, $20
.db $02, $14, $0e, $20
.db $02, $09, $0e, $15
.db $00, $00, $18, $06
.db $00, $00, $20, $0d
.db $00, $00, $30, $0d
.db $00, $00, $08, $08
.db $06, $04, $0a, $08
.db $03, $0e, $0d, $14
.db $00, $02, $10, $15
.db $04, $04, $0c, $1c
GetFireballBoundBox:
txa ;add seven bytes to offset
clc ;to use in routines as offset for fireball
adc #$07
tax
ldy #$02 ;set offset for relative coordinates
bne FBallB ;unconditional branch
GetMiscBoundBox:
txa ;add nine bytes to offset
clc ;to use in routines as offset for misc object
adc #$09
tax
ldy #$06 ;set offset for relative coordinates
FBallB: jsr BoundingBoxCore ;get bounding box coordinates
jmp CheckRightScreenBBox ;jump to handle any offscreen coordinates
GetEnemyBoundBox:
ldy #$48 ;store bitmask here for now
sty $00
ldy #$44 ;store another bitmask here for now and jump
jmp GetMaskedOffScrBits
SmallPlatformBoundBox:
ldy #$08 ;store bitmask here for now
sty $00
ldy #$04 ;store another bitmask here for now
GetMaskedOffScrBits:
lda Enemy_X_Position,x ;get enemy object position relative
sec ;to the left side of the screen
sbc ScreenLeft_X_Pos
sta $01 ;store here
lda Enemy_PageLoc,x ;subtract borrow from current page location
sbc ScreenLeft_PageLoc ;of left side
bmi CMBits ;if enemy object is beyond left edge, branch
ora $01
beq CMBits ;if precisely at the left edge, branch
ldy $00 ;if to the right of left edge, use value in $00 for A
CMBits: tya ;otherwise use contents of Y
and Enemy_OffscreenBits ;preserve bitwise whatever's in here
sta EnemyOffscrBitsMasked,x ;save masked offscreen bits here
bne MoveBoundBoxOffscreen ;if anything set here, branch
jmp SetupEOffsetFBBox ;otherwise, do something else
LargePlatformBoundBox:
inx ;increment X to get the proper offset
jsr GetXOffscreenBits ;then jump directly to the sub for horizontal offscreen bits
dex ;decrement to return to original offset
cmp #$fe ;if completely offscreen, branch to put entire bounding
bcs MoveBoundBoxOffscreen ;box offscreen, otherwise start getting coordinates
SetupEOffsetFBBox:
txa ;add 1 to offset to properly address
clc ;the enemy object memory locations
adc #$01
tax
ldy #$01 ;load 1 as offset here, same reason
jsr BoundingBoxCore ;do a sub to get the coordinates of the bounding box
jmp CheckRightScreenBBox ;jump to handle offscreen coordinates of bounding box
MoveBoundBoxOffscreen:
txa ;multiply offset by 4
asl
asl
tay ;use as offset here
lda #$ff
sta EnemyBoundingBoxCoord,y ;load value into four locations here and leave
sta EnemyBoundingBoxCoord+1,y
sta EnemyBoundingBoxCoord+2,y
sta EnemyBoundingBoxCoord+3,y
rts
BoundingBoxCore:
stx $00 ;save offset here
lda SprObject_Rel_YPos,y ;store object coordinates relative to screen
sta $02 ;vertically and horizontally, respectively
lda SprObject_Rel_XPos,y
sta $01
txa ;multiply offset by four and save to stack
asl
asl
pha
tay ;use as offset for Y, X is left alone
lda SprObj_BoundBoxCtrl,x ;load value here to be used as offset for X
asl ;multiply that by four and use as X
asl
tax
lda $01 ;add the first number in the bounding box data to the
clc ;relative horizontal coordinate using enemy object offset
adc BoundBoxCtrlData,x ;and store somewhere using same offset * 4
sta BoundingBox_UL_Corner,y ;store here
lda $01
clc
adc BoundBoxCtrlData+2,x ;add the third number in the bounding box data to the
sta BoundingBox_LR_Corner,y ;relative horizontal coordinate and store
inx ;increment both offsets
iny
lda $02 ;add the second number to the relative vertical coordinate
clc ;using incremented offset and store using the other
adc BoundBoxCtrlData,x ;incremented offset
sta BoundingBox_UL_Corner,y
lda $02
clc
adc BoundBoxCtrlData+2,x ;add the fourth number to the relative vertical coordinate
sta BoundingBox_LR_Corner,y ;and store
pla ;get original offset loaded into $00 * y from stack
tay ;use as Y
ldx $00 ;get original offset and use as X again
rts
CheckRightScreenBBox:
lda ScreenLeft_X_Pos ;add 128 pixels to left side of screen
clc ;and store as horizontal coordinate of middle
adc #$80
sta $02
lda ScreenLeft_PageLoc ;add carry to page location of left side of screen
adc #$00 ;and store as page location of middle
sta $01
lda SprObject_X_Position,x ;get horizontal coordinate
cmp $02 ;compare against middle horizontal coordinate
lda SprObject_PageLoc,x ;get page location
sbc $01 ;subtract from middle page location
bcc CheckLeftScreenBBox ;if object is on the left side of the screen, branch
lda BoundingBox_DR_XPos,y ;check right-side edge of bounding box for offscreen
bmi NoOfs ;coordinates, branch if still on the screen
lda #$ff ;load offscreen value here to use on one or both horizontal sides
ldx BoundingBox_UL_XPos,y ;check left-side edge of bounding box for offscreen
bmi SORte ;coordinates, and branch if still on the screen
sta BoundingBox_UL_XPos,y ;store offscreen value for left side
SORte: sta BoundingBox_DR_XPos,y ;store offscreen value for right side
NoOfs: ldx ObjectOffset ;get object offset and leave
rts
CheckLeftScreenBBox:
lda BoundingBox_UL_XPos,y ;check left-side edge of bounding box for offscreen
bpl NoOfs2 ;coordinates, and branch if still on the screen
cmp #$a0 ;check to see if left-side edge is in the middle of the
bcc NoOfs2 ;screen or really offscreen, and branch if still on
lda #$00
ldx BoundingBox_DR_XPos,y ;check right-side edge of bounding box for offscreen
bpl SOLft ;coordinates, branch if still onscreen
sta BoundingBox_DR_XPos,y ;store offscreen value for right side
SOLft: sta BoundingBox_UL_XPos,y ;store offscreen value for left side
NoOfs2: ldx ObjectOffset ;get object offset and leave
rts
;-------------------------------------------------------------------------------------
;$06 - second object's offset
;$07 - counter
PlayerCollisionCore:
ldx #$00 ;initialize X to use player's bounding box for comparison
SprObjectCollisionCore:
sty $06 ;save contents of Y here
lda #$01
sta $07 ;save value 1 here as counter, compare horizontal coordinates first
CollisionCoreLoop:
lda BoundingBox_UL_Corner,y ;compare left/top coordinates
cmp BoundingBox_UL_Corner,x ;of first and second objects' bounding boxes
bcs FirstBoxGreater ;if first left/top => second, branch
cmp BoundingBox_LR_Corner,x ;otherwise compare to right/bottom of second
bcc SecondBoxVerticalChk ;if first left/top < second right/bottom, branch elsewhere
beq CollisionFound ;if somehow equal, collision, thus branch
lda BoundingBox_LR_Corner,y ;if somehow greater, check to see if bottom of
cmp BoundingBox_UL_Corner,y ;first object's bounding box is greater than its top
bcc CollisionFound ;if somehow less, vertical wrap collision, thus branch
cmp BoundingBox_UL_Corner,x ;otherwise compare bottom of first bounding box to the top
bcs CollisionFound ;of second box, and if equal or greater, collision, thus branch
ldy $06 ;otherwise return with carry clear and Y = $0006
rts ;note horizontal wrapping never occurs
SecondBoxVerticalChk:
lda BoundingBox_LR_Corner,x ;check to see if the vertical bottom of the box
cmp BoundingBox_UL_Corner,x ;is greater than the vertical top
bcc CollisionFound ;if somehow less, vertical wrap collision, thus branch
lda BoundingBox_LR_Corner,y ;otherwise compare horizontal right or vertical bottom
cmp BoundingBox_UL_Corner,x ;of first box with horizontal left or vertical top of second box
bcs CollisionFound ;if equal or greater, collision, thus branch
ldy $06 ;otherwise return with carry clear and Y = $0006
rts
FirstBoxGreater:
cmp BoundingBox_UL_Corner,x ;compare first and second box horizontal left/vertical top again
beq CollisionFound ;if first coordinate = second, collision, thus branch
cmp BoundingBox_LR_Corner,x ;if not, compare with second object right or bottom edge
bcc CollisionFound ;if left/top of first less than or equal to right/bottom of second
beq CollisionFound ;then collision, thus branch
cmp BoundingBox_LR_Corner,y ;otherwise check to see if top of first box is greater than bottom
bcc NoCollisionFound ;if less than or equal, no collision, branch to end
beq NoCollisionFound
lda BoundingBox_LR_Corner,y ;otherwise compare bottom of first to top of second
cmp BoundingBox_UL_Corner,x ;if bottom of first is greater than top of second, vertical wrap
bcs CollisionFound ;collision, and branch, otherwise, proceed onwards here
NoCollisionFound:
clc ;clear carry, then load value set earlier, then leave
ldy $06 ;like previous ones, if horizontal coordinates do not collide, we do
rts ;not bother checking vertical ones, because what's the point?
CollisionFound:
inx ;increment offsets on both objects to check
iny ;the vertical coordinates
dec $07 ;decrement counter to reflect this
bpl CollisionCoreLoop ;if counter not expired, branch to loop
sec ;otherwise we already did both sets, therefore collision, so set carry
ldy $06 ;load original value set here earlier, then leave
rts
;-------------------------------------------------------------------------------------
;$02 - modified y coordinate
;$03 - stores metatile involved in block buffer collisions
;$04 - comes in with offset to block buffer adder data, goes out with low nybble x/y coordinate
;$05 - modified x coordinate
;$06-$07 - block buffer address
BlockBufferChk_Enemy:
pha ;save contents of A to stack
txa
clc ;add 1 to X to run sub with enemy offset in mind
adc #$01
tax
pla ;pull A from stack and jump elsewhere
jmp BBChk_E
ResidualMiscObjectCode:
txa
clc ;supposedly used once to set offset for
adc #$0d ;miscellaneous objects
tax
ldy #$1b ;supposedly used once to set offset for block buffer data
jmp ResJmpM ;probably used in early stages to do misc to bg collision detection
BlockBufferChk_FBall:
ldy #$1a ;set offset for block buffer adder data
txa
clc
adc #$07 ;add seven bytes to use
tax
ResJmpM: lda #$00 ;set A to return vertical coordinate
BBChk_E: jsr BlockBufferCollision ;do collision detection subroutine for sprite object
ldx ObjectOffset ;get object offset
cmp #$00 ;check to see if object bumped into anything
rts
BlockBufferAdderData:
.db $00, $07, $0e
BlockBuffer_X_Adder:
.db $08, $03, $0c, $02, $02, $0d, $0d, $08
.db $03, $0c, $02, $02, $0d, $0d, $08, $03
.db $0c, $02, $02, $0d, $0d, $08, $00, $10
.db $04, $14, $04, $04
BlockBuffer_Y_Adder:
.db $04, $20, $20, $08, $18, $08, $18, $02
.db $20, $20, $08, $18, $08, $18, $12, $20
.db $20, $18, $18, $18, $18, $18, $14, $14
.db $06, $06, $08, $10
BlockBufferColli_Feet:
iny ;if branched here, increment to next set of adders
BlockBufferColli_Head:
lda #$00 ;set flag to return vertical coordinate
.db $2c ;BIT instruction opcode
BlockBufferColli_Side:
lda #$01 ;set flag to return horizontal coordinate
ldx #$00 ;set offset for player object
BlockBufferCollision:
pha ;save contents of A to stack
sty $04 ;save contents of Y here
lda BlockBuffer_X_Adder,y ;add horizontal coordinate
clc ;of object to value obtained using Y as offset
adc SprObject_X_Position,x
sta $05 ;store here
lda SprObject_PageLoc,x
adc #$00 ;add carry to page location
and #$01 ;get LSB, mask out all other bits
lsr ;move to carry
ora $05 ;get stored value
ror ;rotate carry to MSB of A
lsr ;and effectively move high nybble to
lsr ;lower, LSB which became MSB will be
lsr ;d4 at this point
jsr GetBlockBufferAddr ;get address of block buffer into $06, $07
ldy $04 ;get old contents of Y
lda SprObject_Y_Position,x ;get vertical coordinate of object
clc
adc BlockBuffer_Y_Adder,y ;add it to value obtained using Y as offset
and #%11110000 ;mask out low nybble
sec
sbc #$20 ;subtract 32 pixels for the status bar
sta $02 ;store result here
tay ;use as offset for block buffer
lda ($06),y ;check current content of block buffer
sta $03 ;and store here
ldy $04 ;get old contents of Y again
pla ;pull A from stack
bne RetXC ;if A = 1, branch
lda SprObject_Y_Position,x ;if A = 0, load vertical coordinate
jmp RetYC ;and jump
RetXC: lda SprObject_X_Position,x ;otherwise load horizontal coordinate
RetYC: and #%00001111 ;and mask out high nybble
sta $04 ;store masked out result here
lda $03 ;get saved content of block buffer
rts ;and leave
;-------------------------------------------------------------------------------------
;unused byte
.db $ff
;-------------------------------------------------------------------------------------
;$00 - offset to vine Y coordinate adder
;$02 - offset to sprite data
VineYPosAdder:
.db $00, $30
DrawVine:
sty $00 ;save offset here
lda Enemy_Rel_YPos ;get relative vertical coordinate
clc
adc VineYPosAdder,y ;add value using offset in Y to get value
ldx VineObjOffset,y ;get offset to vine
ldy Enemy_SprDataOffset,x ;get sprite data offset
sty $02 ;store sprite data offset here
jsr SixSpriteStacker ;stack six sprites on top of each other vertically
lda Enemy_Rel_XPos ;get relative horizontal coordinate
sta Sprite_X_Position,y ;store in first, third and fifth sprites
sta Sprite_X_Position+8,y
sta Sprite_X_Position+16,y
clc
adc #$06 ;add six pixels to second, fourth and sixth sprites
sta Sprite_X_Position+4,y ;to give characteristic staggered vine shape to
sta Sprite_X_Position+12,y ;our vertical stack of sprites
sta Sprite_X_Position+20,y
lda #%00100001 ;set bg priority and palette attribute bits
sta Sprite_Attributes,y ;set in first, third and fifth sprites
sta Sprite_Attributes+8,y
sta Sprite_Attributes+16,y
ora #%01000000 ;additionally, set horizontal flip bit
sta Sprite_Attributes+4,y ;for second, fourth and sixth sprites
sta Sprite_Attributes+12,y
sta Sprite_Attributes+20,y
ldx #$05 ;set tiles for six sprites
VineTL: lda #$e1 ;set tile number for sprite
sta Sprite_Tilenumber,y
iny ;move offset to next sprite data
iny
iny
iny
dex ;move onto next sprite
bpl VineTL ;loop until all sprites are done
ldy $02 ;get original offset
lda $00 ;get offset to vine adding data
bne SkpVTop ;if offset not zero, skip this part
lda #$e0
sta Sprite_Tilenumber,y ;set other tile number for top of vine
SkpVTop: ldx #$00 ;start with the first sprite again
ChkFTop: lda VineStart_Y_Position ;get original starting vertical coordinate
sec
sbc Sprite_Y_Position,y ;subtract top-most sprite's Y coordinate
cmp #$64 ;if two coordinates are less than 100/$64 pixels
bcc NextVSp ;apart, skip this to leave sprite alone
lda #$f8
sta Sprite_Y_Position,y ;otherwise move sprite offscreen
NextVSp: iny ;move offset to next OAM data
iny
iny
iny
inx ;move onto next sprite
cpx #$06 ;do this until all sprites are checked
bne ChkFTop
ldy $00 ;return offset set earlier
rts
SixSpriteStacker:
ldx #$06 ;do six sprites
StkLp: sta Sprite_Data,y ;store X or Y coordinate into OAM data
clc
adc #$08 ;add eight pixels
iny
iny ;move offset four bytes forward
iny
iny
dex ;do another sprite
bne StkLp ;do this until all sprites are done
ldy $02 ;get saved OAM data offset and leave
rts
;-------------------------------------------------------------------------------------
FirstSprXPos:
.db $04, $00, $04, $00
FirstSprYPos:
.db $00, $04, $00, $04
SecondSprXPos:
.db $00, $08, $00, $08
SecondSprYPos:
.db $08, $00, $08, $00
FirstSprTilenum:
.db $80, $82, $81, $83
SecondSprTilenum:
.db $81, $83, $80, $82
HammerSprAttrib:
.db $03, $03, $c3, $c3
DrawHammer:
ldy Misc_SprDataOffset,x ;get misc object OAM data offset
lda TimerControl
bne ForceHPose ;if master timer control set, skip this part
lda Misc_State,x ;otherwise get hammer's state
and #%01111111 ;mask out d7
cmp #$01 ;check to see if set to 1 yet
beq GetHPose ;if so, branch
ForceHPose: ldx #$00 ;reset offset here
beq RenderH ;do unconditional branch to rendering part
GetHPose: lda FrameCounter ;get frame counter
lsr ;move d3-d2 to d1-d0
lsr
and #%00000011 ;mask out all but d1-d0 (changes every four frames)
tax ;use as timing offset
RenderH: lda Misc_Rel_YPos ;get relative vertical coordinate
clc
adc FirstSprYPos,x ;add first sprite vertical adder based on offset
sta Sprite_Y_Position,y ;store as sprite Y coordinate for first sprite
clc
adc SecondSprYPos,x ;add second sprite vertical adder based on offset
sta Sprite_Y_Position+4,y ;store as sprite Y coordinate for second sprite
lda Misc_Rel_XPos ;get relative horizontal coordinate
clc
adc FirstSprXPos,x ;add first sprite horizontal adder based on offset
sta Sprite_X_Position,y ;store as sprite X coordinate for first sprite
clc
adc SecondSprXPos,x ;add second sprite horizontal adder based on offset
sta Sprite_X_Position+4,y ;store as sprite X coordinate for second sprite
lda FirstSprTilenum,x
sta Sprite_Tilenumber,y ;get and store tile number of first sprite
lda SecondSprTilenum,x
sta Sprite_Tilenumber+4,y ;get and store tile number of second sprite
lda HammerSprAttrib,x
sta Sprite_Attributes,y ;get and store attribute bytes for both
sta Sprite_Attributes+4,y ;note in this case they use the same data
ldx ObjectOffset ;get misc object offset
lda Misc_OffscreenBits
and #%11111100 ;check offscreen bits
beq NoHOffscr ;if all bits clear, leave object alone
lda #$00
sta Misc_State,x ;otherwise nullify misc object state
lda #$f8
jsr DumpTwoSpr ;do sub to move hammer sprites offscreen
NoHOffscr: rts ;leave
;-------------------------------------------------------------------------------------
;$00-$01 - used to hold tile numbers ($01 addressed in draw floatey number part)
;$02 - used to hold Y coordinate for floatey number
;$03 - residual byte used for flip (but value set here affects nothing)
;$04 - attribute byte for floatey number
;$05 - used as X coordinate for floatey number
FlagpoleScoreNumTiles:
.db $f9, $50
.db $f7, $50
.db $fa, $fb
.db $f8, $fb
.db $f6, $fb
FlagpoleGfxHandler:
ldy Enemy_SprDataOffset,x ;get sprite data offset for flagpole flag
lda Enemy_Rel_XPos ;get relative horizontal coordinate
sta Sprite_X_Position,y ;store as X coordinate for first sprite
clc
adc #$08 ;add eight pixels and store
sta Sprite_X_Position+4,y ;as X coordinate for second and third sprites
sta Sprite_X_Position+8,y
clc
adc #$0c ;add twelve more pixels and
sta $05 ;store here to be used later by floatey number
lda Enemy_Y_Position,x ;get vertical coordinate
jsr DumpTwoSpr ;and do sub to dump into first and second sprites
adc #$08 ;add eight pixels
sta Sprite_Y_Position+8,y ;and store into third sprite
lda FlagpoleFNum_Y_Pos ;get vertical coordinate for floatey number
sta $02 ;store it here
lda #$01
sta $03 ;set value for flip which will not be used, and
sta $04 ;attribute byte for floatey number
sta Sprite_Attributes,y ;set attribute bytes for all three sprites
sta Sprite_Attributes+4,y
sta Sprite_Attributes+8,y
lda #$7e
sta Sprite_Tilenumber,y ;put triangle shaped tile
sta Sprite_Tilenumber+8,y ;into first and third sprites
lda #$7f
sta Sprite_Tilenumber+4,y ;put skull tile into second sprite
lda FlagpoleCollisionYPos ;get vertical coordinate at time of collision
beq ChkFlagOffscreen ;if zero, branch ahead
tya
clc ;add 12 bytes to sprite data offset
adc #$0c
tay ;put back in Y
lda FlagpoleScore ;get offset used to award points for touching flagpole
asl ;multiply by 2 to get proper offset here
tax
lda FlagpoleScoreNumTiles,x ;get appropriate tile data
sta $00
lda FlagpoleScoreNumTiles+1,x
jsr DrawOneSpriteRow ;use it to render floatey number
ChkFlagOffscreen:
ldx ObjectOffset ;get object offset for flag
ldy Enemy_SprDataOffset,x ;get OAM data offset
lda Enemy_OffscreenBits ;get offscreen bits
and #%00001110 ;mask out all but d3-d1
beq ExitDumpSpr ;if none of these bits set, branch to leave
;-------------------------------------------------------------------------------------
MoveSixSpritesOffscreen:
lda #$f8 ;set offscreen coordinate if jumping here
DumpSixSpr:
sta Sprite_Data+20,y ;dump A contents
sta Sprite_Data+16,y ;into third row sprites
DumpFourSpr:
sta Sprite_Data+12,y ;into second row sprites
DumpThreeSpr:
sta Sprite_Data+8,y
DumpTwoSpr:
sta Sprite_Data+4,y ;and into first row sprites
sta Sprite_Data,y
ExitDumpSpr:
rts
;-------------------------------------------------------------------------------------
DrawLargePlatform:
ldy Enemy_SprDataOffset,x ;get OAM data offset
sty $02 ;store here
iny ;add 3 to it for offset
iny ;to X coordinate
iny
lda Enemy_Rel_XPos ;get horizontal relative coordinate
jsr SixSpriteStacker ;store X coordinates using A as base, stack horizontally
ldx ObjectOffset
lda Enemy_Y_Position,x ;get vertical coordinate
jsr DumpFourSpr ;dump into first four sprites as Y coordinate
ldy AreaType
cpy #$03 ;check for castle-type level
beq ShrinkPlatform
ldy SecondaryHardMode ;check for secondary hard mode flag set
beq SetLast2Platform ;branch if not set elsewhere
ShrinkPlatform:
lda #$f8 ;load offscreen coordinate if flag set or castle-type level
SetLast2Platform:
ldy Enemy_SprDataOffset,x ;get OAM data offset
sta Sprite_Y_Position+16,y ;store vertical coordinate or offscreen
sta Sprite_Y_Position+20,y ;coordinate into last two sprites as Y coordinate
lda #$5b ;load default tile for platform (girder)
ldx CloudTypeOverride
beq SetPlatformTilenum ;if cloud level override flag not set, use
lda #$75 ;otherwise load other tile for platform (puff)
SetPlatformTilenum:
ldx ObjectOffset ;get enemy object buffer offset
iny ;increment Y for tile offset
jsr DumpSixSpr ;dump tile number into all six sprites
lda #$02 ;set palette controls
iny ;increment Y for sprite attributes
jsr DumpSixSpr ;dump attributes into all six sprites
inx ;increment X for enemy objects
jsr GetXOffscreenBits ;get offscreen bits again
dex
ldy Enemy_SprDataOffset,x ;get OAM data offset
asl ;rotate d7 into carry, save remaining
pha ;bits to the stack
bcc SChk2
lda #$f8 ;if d7 was set, move first sprite offscreen
sta Sprite_Y_Position,y
SChk2: pla ;get bits from stack
asl ;rotate d6 into carry
pha ;save to stack
bcc SChk3
lda #$f8 ;if d6 was set, move second sprite offscreen
sta Sprite_Y_Position+4,y
SChk3: pla ;get bits from stack
asl ;rotate d5 into carry
pha ;save to stack
bcc SChk4
lda #$f8 ;if d5 was set, move third sprite offscreen
sta Sprite_Y_Position+8,y
SChk4: pla ;get bits from stack
asl ;rotate d4 into carry
pha ;save to stack
bcc SChk5
lda #$f8 ;if d4 was set, move fourth sprite offscreen
sta Sprite_Y_Position+12,y
SChk5: pla ;get bits from stack
asl ;rotate d3 into carry
pha ;save to stack
bcc SChk6
lda #$f8 ;if d3 was set, move fifth sprite offscreen
sta Sprite_Y_Position+16,y
SChk6: pla ;get bits from stack
asl ;rotate d2 into carry
bcc SLChk ;save to stack
lda #$f8
sta Sprite_Y_Position+20,y ;if d2 was set, move sixth sprite offscreen
SLChk: lda Enemy_OffscreenBits ;check d7 of offscreen bits
asl ;and if d7 is not set, skip sub
bcc ExDLPl
jsr MoveSixSpritesOffscreen ;otherwise branch to move all sprites offscreen
ExDLPl: rts
;-------------------------------------------------------------------------------------
DrawFloateyNumber_Coin:
lda FrameCounter ;get frame counter
lsr ;divide by 2
bcs NotRsNum ;branch if d0 not set to raise number every other frame
dec Misc_Y_Position,x ;otherwise, decrement vertical coordinate
NotRsNum: lda Misc_Y_Position,x ;get vertical coordinate
jsr DumpTwoSpr ;dump into both sprites
lda Misc_Rel_XPos ;get relative horizontal coordinate
sta Sprite_X_Position,y ;store as X coordinate for first sprite
clc
adc #$08 ;add eight pixels
sta Sprite_X_Position+4,y ;store as X coordinate for second sprite
lda #$02
sta Sprite_Attributes,y ;store attribute byte in both sprites
sta Sprite_Attributes+4,y
lda #$f7
sta Sprite_Tilenumber,y ;put tile numbers into both sprites
lda #$fb ;that resemble "200"
sta Sprite_Tilenumber+4,y
jmp ExJCGfx ;then jump to leave (why not an rts here instead?)
JumpingCoinTiles:
.db $60, $61, $62, $63
JCoinGfxHandler:
ldy Misc_SprDataOffset,x ;get coin/floatey number's OAM data offset
lda Misc_State,x ;get state of misc object
cmp #$02 ;if 2 or greater,
bcs DrawFloateyNumber_Coin ;branch to draw floatey number
lda Misc_Y_Position,x ;store vertical coordinate as
sta Sprite_Y_Position,y ;Y coordinate for first sprite
clc
adc #$08 ;add eight pixels
sta Sprite_Y_Position+4,y ;store as Y coordinate for second sprite
lda Misc_Rel_XPos ;get relative horizontal coordinate
sta Sprite_X_Position,y
sta Sprite_X_Position+4,y ;store as X coordinate for first and second sprites
lda FrameCounter ;get frame counter
lsr ;divide by 2 to alter every other frame
and #%00000011 ;mask out d2-d1
tax ;use as graphical offset
lda JumpingCoinTiles,x ;load tile number
iny ;increment OAM data offset to write tile numbers
jsr DumpTwoSpr ;do sub to dump tile number into both sprites
dey ;decrement to get old offset
lda #$02
sta Sprite_Attributes,y ;set attribute byte in first sprite
lda #$82
sta Sprite_Attributes+4,y ;set attribute byte with vertical flip in second sprite
ldx ObjectOffset ;get misc object offset
ExJCGfx: rts ;leave
;-------------------------------------------------------------------------------------
;$00-$01 - used to hold tiles for drawing the power-up, $00 also used to hold power-up type
;$02 - used to hold bottom row Y position
;$03 - used to hold flip control (not used here)
;$04 - used to hold sprite attributes
;$05 - used to hold X position
;$07 - counter
;tiles arranged in top left, right, bottom left, right order
PowerUpGfxTable:
.db $76, $77, $78, $79 ;regular mushroom
.db $d6, $d6, $d9, $d9 ;fire flower
.db $8d, $8d, $e4, $e4 ;star
.db $76, $77, $78, $79 ;1-up mushroom
PowerUpAttributes:
.db $02, $01, $02, $01
DrawPowerUp:
ldy Enemy_SprDataOffset+5 ;get power-up's sprite data offset
lda Enemy_Rel_YPos ;get relative vertical coordinate
clc
adc #$08 ;add eight pixels
sta $02 ;store result here
lda Enemy_Rel_XPos ;get relative horizontal coordinate
sta $05 ;store here
ldx PowerUpType ;get power-up type
lda PowerUpAttributes,x ;get attribute data for power-up type
ora Enemy_SprAttrib+5 ;add background priority bit if set
sta $04 ;store attributes here
txa
pha ;save power-up type to the stack
asl
asl ;multiply by four to get proper offset
tax ;use as X
lda #$01
sta $07 ;set counter here to draw two rows of sprite object
sta $03 ;init d1 of flip control
PUpDrawLoop:
lda PowerUpGfxTable,x ;load left tile of power-up object
sta $00
lda PowerUpGfxTable+1,x ;load right tile
jsr DrawOneSpriteRow ;branch to draw one row of our power-up object
dec $07 ;decrement counter
bpl PUpDrawLoop ;branch until two rows are drawn
ldy Enemy_SprDataOffset+5 ;get sprite data offset again
pla ;pull saved power-up type from the stack
beq PUpOfs ;if regular mushroom, branch, do not change colors or flip
cmp #$03
beq PUpOfs ;if 1-up mushroom, branch, do not change colors or flip
sta $00 ;store power-up type here now
lda FrameCounter ;get frame counter
lsr ;divide by 2 to change colors every two frames
and #%00000011 ;mask out all but d1 and d0 (previously d2 and d1)
ora Enemy_SprAttrib+5 ;add background priority bit if any set
sta Sprite_Attributes,y ;set as new palette bits for top left and
sta Sprite_Attributes+4,y ;top right sprites for fire flower and star
ldx $00
dex ;check power-up type for fire flower
beq FlipPUpRightSide ;if found, skip this part
sta Sprite_Attributes+8,y ;otherwise set new palette bits for bottom left
sta Sprite_Attributes+12,y ;and bottom right sprites as well for star only
FlipPUpRightSide:
lda Sprite_Attributes+4,y
ora #%01000000 ;set horizontal flip bit for top right sprite
sta Sprite_Attributes+4,y
lda Sprite_Attributes+12,y
ora #%01000000 ;set horizontal flip bit for bottom right sprite
sta Sprite_Attributes+12,y ;note these are only done for fire flower and star power-ups
PUpOfs: jmp SprObjectOffscrChk ;jump to check to see if power-up is offscreen at all, then leave
;-------------------------------------------------------------------------------------
;$00-$01 - used in DrawEnemyObjRow to hold sprite tile numbers
;$02 - used to store Y position
;$03 - used to store moving direction, used to flip enemies horizontally
;$04 - used to store enemy's sprite attributes
;$05 - used to store X position
;$eb - used to hold sprite data offset
;$ec - used to hold either altered enemy state or special value used in gfx handler as condition
;$ed - used to hold enemy state from buffer
;$ef - used to hold enemy code used in gfx handler (may or may not resemble Enemy_ID values)
;tiles arranged in top left, right, middle left, right, bottom left, right order
EnemyGraphicsTable:
.db $fc, $fc, $aa, $ab, $ac, $ad ;buzzy beetle frame 1
.db $fc, $fc, $ae, $af, $b0, $b1 ; frame 2
.db $fc, $a5, $a6, $a7, $a8, $a9 ;koopa troopa frame 1
.db $fc, $a0, $a1, $a2, $a3, $a4 ; frame 2
.db $69, $a5, $6a, $a7, $a8, $a9 ;koopa paratroopa frame 1
.db $6b, $a0, $6c, $a2, $a3, $a4 ; frame 2
.db $fc, $fc, $96, $97, $98, $99 ;spiny frame 1
.db $fc, $fc, $9a, $9b, $9c, $9d ; frame 2
.db $fc, $fc, $8f, $8e, $8e, $8f ;spiny's egg frame 1
.db $fc, $fc, $95, $94, $94, $95 ; frame 2
.db $fc, $fc, $dc, $dc, $df, $df ;bloober frame 1
.db $dc, $dc, $dd, $dd, $de, $de ; frame 2
.db $fc, $fc, $b2, $b3, $b4, $b5 ;cheep-cheep frame 1
.db $fc, $fc, $b6, $b3, $b7, $b5 ; frame 2
.db $fc, $fc, $70, $71, $72, $73 ;goomba
.db $fc, $fc, $6e, $6e, $6f, $6f ;koopa shell frame 1 (upside-down)
.db $fc, $fc, $6d, $6d, $6f, $6f ; frame 2
.db $fc, $fc, $6f, $6f, $6e, $6e ;koopa shell frame 1 (rightsideup)
.db $fc, $fc, $6f, $6f, $6d, $6d ; frame 2
.db $fc, $fc, $f4, $f4, $f5, $f5 ;buzzy beetle shell frame 1 (rightsideup)
.db $fc, $fc, $f4, $f4, $f5, $f5 ; frame 2
.db $fc, $fc, $f5, $f5, $f4, $f4 ;buzzy beetle shell frame 1 (upside-down)
.db $fc, $fc, $f5, $f5, $f4, $f4 ; frame 2
.db $fc, $fc, $fc, $fc, $ef, $ef ;defeated goomba
.db $b9, $b8, $bb, $ba, $bc, $bc ;lakitu frame 1
.db $fc, $fc, $bd, $bd, $bc, $bc ; frame 2
.db $7a, $7b, $da, $db, $d8, $d8 ;princess
.db $cd, $cd, $ce, $ce, $cf, $cf ;mushroom retainer
.db $7d, $7c, $d1, $8c, $d3, $d2 ;hammer bro frame 1
.db $7d, $7c, $89, $88, $8b, $8a ; frame 2
.db $d5, $d4, $e3, $e2, $d3, $d2 ; frame 3
.db $d5, $d4, $e3, $e2, $8b, $8a ; frame 4
.db $e5, $e5, $e6, $e6, $eb, $eb ;piranha plant frame 1
.db $ec, $ec, $ed, $ed, $ee, $ee ; frame 2
.db $fc, $fc, $d0, $d0, $d7, $d7 ;podoboo
.db $bf, $be, $c1, $c0, $c2, $fc ;bowser front frame 1
.db $c4, $c3, $c6, $c5, $c8, $c7 ;bowser rear frame 1
.db $bf, $be, $ca, $c9, $c2, $fc ; front frame 2
.db $c4, $c3, $c6, $c5, $cc, $cb ; rear frame 2
.db $fc, $fc, $e8, $e7, $ea, $e9 ;bullet bill
.db $f2, $f2, $f3, $f3, $f2, $f2 ;jumpspring frame 1
.db $f1, $f1, $f1, $f1, $fc, $fc ; frame 2
.db $f0, $f0, $fc, $fc, $fc, $fc ; frame 3
EnemyGfxTableOffsets:
.db $0c, $0c, $00, $0c, $0c, $a8, $54, $3c
.db $ea, $18, $48, $48, $cc, $c0, $18, $18
.db $18, $90, $24, $ff, $48, $9c, $d2, $d8
.db $f0, $f6, $fc
EnemyAttributeData:
.db $01, $02, $03, $02, $01, $01, $03, $03
.db $03, $01, $01, $02, $02, $21, $01, $02
.db $01, $01, $02, $ff, $02, $02, $01, $01
.db $02, $02, $02
EnemyAnimTimingBMask:
.db $08, $18
JumpspringFrameOffsets:
.db $18, $19, $1a, $19, $18
EnemyGfxHandler:
lda Enemy_Y_Position,x ;get enemy object vertical position
sta $02
lda Enemy_Rel_XPos ;get enemy object horizontal position
sta $05 ;relative to screen
ldy Enemy_SprDataOffset,x
sty $eb ;get sprite data offset
lda #$00
sta VerticalFlipFlag ;initialize vertical flip flag by default
lda Enemy_MovingDir,x
sta $03 ;get enemy object moving direction
lda Enemy_SprAttrib,x
sta $04 ;get enemy object sprite attributes
lda Enemy_ID,x
cmp #PiranhaPlant ;is enemy object piranha plant?
bne CheckForRetainerObj ;if not, branch
ldy PiranhaPlant_Y_Speed,x
bmi CheckForRetainerObj ;if piranha plant moving upwards, branch
ldy EnemyFrameTimer,x
beq CheckForRetainerObj ;if timer for movement expired, branch
rts ;if all conditions fail, leave
CheckForRetainerObj:
lda Enemy_State,x ;store enemy state
sta $ed
and #%00011111 ;nullify all but 5 LSB and use as Y
tay
lda Enemy_ID,x ;check for mushroom retainer/princess object
cmp #RetainerObject
bne CheckForBulletBillCV ;if not found, branch
ldy #$00 ;if found, nullify saved state in Y
lda #$01 ;set value that will not be used
sta $03
lda #$15 ;set value $15 as code for mushroom retainer/princess object
CheckForBulletBillCV:
cmp #BulletBill_CannonVar ;otherwise check for bullet bill object
bne CheckForJumpspring ;if not found, branch again
dec $02 ;decrement saved vertical position
lda #$03
ldy EnemyFrameTimer,x ;get timer for enemy object
beq SBBAt ;if expired, do not set priority bit
ora #%00100000 ;otherwise do so
SBBAt: sta $04 ;set new sprite attributes
ldy #$00 ;nullify saved enemy state both in Y and in
sty $ed ;memory location here
lda #$08 ;set specific value to unconditionally branch once
CheckForJumpspring:
cmp #JumpspringObject ;check for jumpspring object
bne CheckForPodoboo
ldy #$03 ;set enemy state -2 MSB here for jumpspring object
ldx JumpspringAnimCtrl ;get current frame number for jumpspring object
lda JumpspringFrameOffsets,x ;load data using frame number as offset
CheckForPodoboo:
sta $ef ;store saved enemy object value here
sty $ec ;and Y here (enemy state -2 MSB if not changed)
ldx ObjectOffset ;get enemy object offset
cmp #$0c ;check for podoboo object
bne CheckBowserGfxFlag ;branch if not found
lda Enemy_Y_Speed,x ;if moving upwards, branch
bmi CheckBowserGfxFlag
inc VerticalFlipFlag ;otherwise, set flag for vertical flip
CheckBowserGfxFlag:
lda BowserGfxFlag ;if not drawing bowser at all, skip to something else
beq CheckForGoomba
ldy #$16 ;if set to 1, draw bowser's front
cmp #$01
beq SBwsrGfxOfs
iny ;otherwise draw bowser's rear
SBwsrGfxOfs: sty $ef
CheckForGoomba:
ldy $ef ;check value for goomba object
cpy #Goomba
bne CheckBowserFront ;branch if not found
lda Enemy_State,x
cmp #$02 ;check for defeated state
bcc GmbaAnim ;if not defeated, go ahead and animate
ldx #$04 ;if defeated, write new value here
stx $ec
GmbaAnim: and #%00100000 ;check for d5 set in enemy object state
ora TimerControl ;or timer disable flag set
bne CheckBowserFront ;if either condition true, do not animate goomba
lda FrameCounter
and #%00001000 ;check for every eighth frame
bne CheckBowserFront
lda $03
eor #%00000011 ;invert bits to flip horizontally every eight frames
sta $03 ;leave alone otherwise
CheckBowserFront:
lda EnemyAttributeData,y ;load sprite attribute using enemy object
ora $04 ;as offset, and add to bits already loaded
sta $04
lda EnemyGfxTableOffsets,y ;load value based on enemy object as offset
tax ;save as X
ldy $ec ;get previously saved value
lda BowserGfxFlag
beq CheckForSpiny ;if not drawing bowser object at all, skip all of this
cmp #$01
bne CheckBowserRear ;if not drawing front part, branch to draw the rear part
lda BowserBodyControls ;check bowser's body control bits
bpl ChkFrontSte ;branch if d7 not set (control's bowser's mouth)
ldx #$de ;otherwise load offset for second frame
ChkFrontSte: lda $ed ;check saved enemy state
and #%00100000 ;if bowser not defeated, do not set flag
beq DrawBowser
FlipBowserOver:
stx VerticalFlipFlag ;set vertical flip flag to nonzero
DrawBowser:
jmp DrawEnemyObject ;draw bowser's graphics now
CheckBowserRear:
lda BowserBodyControls ;check bowser's body control bits
and #$01
beq ChkRearSte ;branch if d0 not set (control's bowser's feet)
ldx #$e4 ;otherwise load offset for second frame
ChkRearSte: lda $ed ;check saved enemy state
and #%00100000 ;if bowser not defeated, do not set flag
beq DrawBowser
lda $02 ;subtract 16 pixels from
sec ;saved vertical coordinate
sbc #$10
sta $02
jmp FlipBowserOver ;jump to set vertical flip flag
CheckForSpiny:
cpx #$24 ;check if value loaded is for spiny
bne CheckForLakitu ;if not found, branch
cpy #$05 ;if enemy state set to $05, do this,
bne NotEgg ;otherwise branch
ldx #$30 ;set to spiny egg offset
lda #$02
sta $03 ;set enemy direction to reverse sprites horizontally
lda #$05
sta $ec ;set enemy state
NotEgg: jmp CheckForHammerBro ;skip a big chunk of this if we found spiny but not in egg
CheckForLakitu:
cpx #$90 ;check value for lakitu's offset loaded
bne CheckUpsideDownShell ;branch if not loaded
lda $ed
and #%00100000 ;check for d5 set in enemy state
bne NoLAFr ;branch if set
lda FrenzyEnemyTimer
cmp #$10 ;check timer to see if we've reached a certain range
bcs NoLAFr ;branch if not
ldx #$96 ;if d6 not set and timer in range, load alt frame for lakitu
NoLAFr: jmp CheckDefeatedState ;skip this next part if we found lakitu but alt frame not needed
CheckUpsideDownShell:
lda $ef ;check for enemy object => $04
cmp #$04
bcs CheckRightSideUpShell ;branch if true
cpy #$02
bcc CheckRightSideUpShell ;branch if enemy state < $02
ldx #$5a ;set for upside-down koopa shell by default
ldy $ef
cpy #BuzzyBeetle ;check for buzzy beetle object
bne CheckRightSideUpShell
ldx #$7e ;set for upside-down buzzy beetle shell if found
inc $02 ;increment vertical position by one pixel
CheckRightSideUpShell:
lda $ec ;check for value set here
cmp #$04 ;if enemy state < $02, do not change to shell, if
bne CheckForHammerBro ;enemy state => $02 but not = $04, leave shell upside-down
ldx #$72 ;set right-side up buzzy beetle shell by default
inc $02 ;increment saved vertical position by one pixel
ldy $ef
cpy #BuzzyBeetle ;check for buzzy beetle object
beq CheckForDefdGoomba ;branch if found
ldx #$66 ;change to right-side up koopa shell if not found
inc $02 ;and increment saved vertical position again
CheckForDefdGoomba:
cpy #Goomba ;check for goomba object (necessary if previously
bne CheckForHammerBro ;failed buzzy beetle object test)
ldx #$54 ;load for regular goomba
lda $ed ;note that this only gets performed if enemy state => $02
and #%00100000 ;check saved enemy state for d5 set
bne CheckForHammerBro ;branch if set
ldx #$8a ;load offset for defeated goomba
dec $02 ;set different value and decrement saved vertical position
CheckForHammerBro:
ldy ObjectOffset
lda $ef ;check for hammer bro object
cmp #HammerBro
bne CheckForBloober ;branch if not found
lda $ed
beq CheckToAnimateEnemy ;branch if not in normal enemy state
and #%00001000
beq CheckDefeatedState ;if d3 not set, branch further away
ldx #$b4 ;otherwise load offset for different frame
bne CheckToAnimateEnemy ;unconditional branch
CheckForBloober:
cpx #$48 ;check for cheep-cheep offset loaded
beq CheckToAnimateEnemy ;branch if found
lda EnemyIntervalTimer,y
cmp #$05
bcs CheckDefeatedState ;branch if some timer is above a certain point
cpx #$3c ;check for bloober offset loaded
bne CheckToAnimateEnemy ;branch if not found this time
cmp #$01
beq CheckDefeatedState ;branch if timer is set to certain point
inc $02 ;increment saved vertical coordinate three pixels
inc $02
inc $02
jmp CheckAnimationStop ;and do something else
CheckToAnimateEnemy:
lda $ef ;check for specific enemy objects
cmp #Goomba
beq CheckDefeatedState ;branch if goomba
cmp #$08
beq CheckDefeatedState ;branch if bullet bill (note both variants use $08 here)
cmp #Podoboo
beq CheckDefeatedState ;branch if podoboo
cmp #$18 ;branch if => $18
bcs CheckDefeatedState
ldy #$00
cmp #$15 ;check for mushroom retainer/princess object
bne CheckForSecondFrame ;which uses different code here, branch if not found
iny ;residual instruction
lda WorldNumber ;are we on world 8?
cmp #World8
bcs CheckDefeatedState ;if so, leave the offset alone (use princess)
ldx #$a2 ;otherwise, set for mushroom retainer object instead
lda #$03 ;set alternate state here
sta $ec
bne CheckDefeatedState ;unconditional branch
CheckForSecondFrame:
lda FrameCounter ;load frame counter
and EnemyAnimTimingBMask,y ;mask it (partly residual, one byte not ever used)
bne CheckDefeatedState ;branch if timing is off
CheckAnimationStop:
lda $ed ;check saved enemy state
and #%10100000 ;for d7 or d5, or check for timers stopped
ora TimerControl
bne CheckDefeatedState ;if either condition true, branch
txa
clc
adc #$06 ;add $06 to current enemy offset
tax ;to animate various enemy objects
CheckDefeatedState:
lda $ed ;check saved enemy state
and #%00100000 ;for d5 set
beq DrawEnemyObject ;branch if not set
lda $ef
cmp #$04 ;check for saved enemy object => $04
bcc DrawEnemyObject ;branch if less
ldy #$01
sty VerticalFlipFlag ;set vertical flip flag
dey
sty $ec ;init saved value here
DrawEnemyObject:
ldy $eb ;load sprite data offset
jsr DrawEnemyObjRow ;draw six tiles of data
jsr DrawEnemyObjRow ;into sprite data
jsr DrawEnemyObjRow
ldx ObjectOffset ;get enemy object offset
ldy Enemy_SprDataOffset,x ;get sprite data offset
lda $ef
cmp #$08 ;get saved enemy object and check
bne CheckForVerticalFlip ;for bullet bill, branch if not found
SkipToOffScrChk:
jmp SprObjectOffscrChk ;jump if found
CheckForVerticalFlip:
lda VerticalFlipFlag ;check if vertical flip flag is set here
beq CheckForESymmetry ;branch if not
lda Sprite_Attributes,y ;get attributes of first sprite we dealt with
ora #%10000000 ;set bit for vertical flip
iny
iny ;increment two bytes so that we store the vertical flip
jsr DumpSixSpr ;in attribute bytes of enemy obj sprite data
dey
dey ;now go back to the Y coordinate offset
tya
tax ;give offset to X
lda $ef
cmp #HammerBro ;check saved enemy object for hammer bro
beq FlipEnemyVertically
cmp #Lakitu ;check saved enemy object for lakitu
beq FlipEnemyVertically ;branch for hammer bro or lakitu
cmp #$15
bcs FlipEnemyVertically ;also branch if enemy object => $15
txa
clc
adc #$08 ;if not selected objects or => $15, set
tax ;offset in X for next row
FlipEnemyVertically:
lda Sprite_Tilenumber,x ;load first or second row tiles
pha ;and save tiles to the stack
lda Sprite_Tilenumber+4,x
pha
lda Sprite_Tilenumber+16,y ;exchange third row tiles
sta Sprite_Tilenumber,x ;with first or second row tiles
lda Sprite_Tilenumber+20,y
sta Sprite_Tilenumber+4,x
pla ;pull first or second row tiles from stack
sta Sprite_Tilenumber+20,y ;and save in third row
pla
sta Sprite_Tilenumber+16,y
CheckForESymmetry:
lda BowserGfxFlag ;are we drawing bowser at all?
bne SkipToOffScrChk ;branch if so
lda $ef
ldx $ec ;get alternate enemy state
cmp #$05 ;check for hammer bro object
bne ContES
jmp SprObjectOffscrChk ;jump if found
ContES: cmp #Bloober ;check for bloober object
beq MirrorEnemyGfx
cmp #PiranhaPlant ;check for piranha plant object
beq MirrorEnemyGfx
cmp #Podoboo ;check for podoboo object
beq MirrorEnemyGfx ;branch if either of three are found
cmp #Spiny ;check for spiny object
bne ESRtnr ;branch closer if not found
cpx #$05 ;check spiny's state
bne CheckToMirrorLakitu ;branch if not an egg, otherwise
ESRtnr: cmp #$15 ;check for princess/mushroom retainer object
bne SpnySC
lda #$42 ;set horizontal flip on bottom right sprite
sta Sprite_Attributes+20,y ;note that palette bits were already set earlier
SpnySC: cpx #$02 ;if alternate enemy state set to 1 or 0, branch
bcc CheckToMirrorLakitu
MirrorEnemyGfx:
lda BowserGfxFlag ;if enemy object is bowser, skip all of this
bne CheckToMirrorLakitu
lda Sprite_Attributes,y ;load attribute bits of first sprite
and #%10100011
sta Sprite_Attributes,y ;save vertical flip, priority, and palette bits
sta Sprite_Attributes+8,y ;in left sprite column of enemy object OAM data
sta Sprite_Attributes+16,y
ora #%01000000 ;set horizontal flip
cpx #$05 ;check for state used by spiny's egg
bne EggExc ;if alternate state not set to $05, branch
ora #%10000000 ;otherwise set vertical flip
EggExc: sta Sprite_Attributes+4,y ;set bits of right sprite column
sta Sprite_Attributes+12,y ;of enemy object sprite data
sta Sprite_Attributes+20,y
cpx #$04 ;check alternate enemy state
bne CheckToMirrorLakitu ;branch if not $04
lda Sprite_Attributes+8,y ;get second row left sprite attributes
ora #%10000000
sta Sprite_Attributes+8,y ;store bits with vertical flip in
sta Sprite_Attributes+16,y ;second and third row left sprites
ora #%01000000
sta Sprite_Attributes+12,y ;store with horizontal and vertical flip in
sta Sprite_Attributes+20,y ;second and third row right sprites
CheckToMirrorLakitu:
lda $ef ;check for lakitu enemy object
cmp #Lakitu
bne CheckToMirrorJSpring ;branch if not found
lda VerticalFlipFlag
bne NVFLak ;branch if vertical flip flag not set
lda Sprite_Attributes+16,y ;save vertical flip and palette bits
and #%10000001 ;in third row left sprite
sta Sprite_Attributes+16,y
lda Sprite_Attributes+20,y ;set horizontal flip and palette bits
ora #%01000001 ;in third row right sprite
sta Sprite_Attributes+20,y
ldx FrenzyEnemyTimer ;check timer
cpx #$10
bcs SprObjectOffscrChk ;branch if timer has not reached a certain range
sta Sprite_Attributes+12,y ;otherwise set same for second row right sprite
and #%10000001
sta Sprite_Attributes+8,y ;preserve vertical flip and palette bits for left sprite
bcc SprObjectOffscrChk ;unconditional branch
NVFLak: lda Sprite_Attributes,y ;get first row left sprite attributes
and #%10000001
sta Sprite_Attributes,y ;save vertical flip and palette bits
lda Sprite_Attributes+4,y ;get first row right sprite attributes
ora #%01000001 ;set horizontal flip and palette bits
sta Sprite_Attributes+4,y ;note that vertical flip is left as-is
CheckToMirrorJSpring:
lda $ef ;check for jumpspring object (any frame)
cmp #$18
bcc SprObjectOffscrChk ;branch if not jumpspring object at all
lda #$82
sta Sprite_Attributes+8,y ;set vertical flip and palette bits of
sta Sprite_Attributes+16,y ;second and third row left sprites
ora #%01000000
sta Sprite_Attributes+12,y ;set, in addition to those, horizontal flip
sta Sprite_Attributes+20,y ;for second and third row right sprites
SprObjectOffscrChk:
ldx ObjectOffset ;get enemy buffer offset
lda Enemy_OffscreenBits ;check offscreen information
lsr
lsr ;shift three times to the right
lsr ;which puts d2 into carry
pha ;save to stack
bcc LcChk ;branch if not set
lda #$04 ;set for right column sprites
jsr MoveESprColOffscreen ;and move them offscreen
LcChk: pla ;get from stack
lsr ;move d3 to carry
pha ;save to stack
bcc Row3C ;branch if not set
lda #$00 ;set for left column sprites,
jsr MoveESprColOffscreen ;move them offscreen
Row3C: pla ;get from stack again
lsr ;move d5 to carry this time
lsr
pha ;save to stack again
bcc Row23C ;branch if carry not set
lda #$10 ;set for third row of sprites
jsr MoveESprRowOffscreen ;and move them offscreen
Row23C: pla ;get from stack
lsr ;move d6 into carry
pha ;save to stack
bcc AllRowC
lda #$08 ;set for second and third rows
jsr MoveESprRowOffscreen ;move them offscreen
AllRowC: pla ;get from stack once more
lsr ;move d7 into carry
bcc ExEGHandler
jsr MoveESprRowOffscreen ;move all sprites offscreen (A should be 0 by now)
lda Enemy_ID,x
cmp #Podoboo ;check enemy identifier for podoboo
beq ExEGHandler ;skip this part if found, we do not want to erase podoboo!
lda Enemy_Y_HighPos,x ;check high byte of vertical position
cmp #$02 ;if not yet past the bottom of the screen, branch
bne ExEGHandler
jsr EraseEnemyObject ;what it says
ExEGHandler:
rts
DrawEnemyObjRow:
lda EnemyGraphicsTable,x ;load two tiles of enemy graphics
sta $00
lda EnemyGraphicsTable+1,x
DrawOneSpriteRow:
sta $01
jmp DrawSpriteObject ;draw them
MoveESprRowOffscreen:
clc ;add A to enemy object OAM data offset
adc Enemy_SprDataOffset,x
tay ;use as offset
lda #$f8
jmp DumpTwoSpr ;move first row of sprites offscreen
MoveESprColOffscreen:
clc ;add A to enemy object OAM data offset
adc Enemy_SprDataOffset,x
tay ;use as offset
jsr MoveColOffscreen ;move first and second row sprites in column offscreen
sta Sprite_Data+16,y ;move third row sprite in column offscreen
rts
;-------------------------------------------------------------------------------------
;$00-$01 - tile numbers
;$02 - relative Y position
;$03 - horizontal flip flag (not used here)
;$04 - attributes
;$05 - relative X position
DefaultBlockObjTiles:
.db $85, $85, $86, $86 ;brick w/ line (these are sprite tiles, not BG!)
DrawBlock:
lda Block_Rel_YPos ;get relative vertical coordinate of block object
sta $02 ;store here
lda Block_Rel_XPos ;get relative horizontal coordinate of block object
sta $05 ;store here
lda #$03
sta $04 ;set attribute byte here
lsr
sta $03 ;set horizontal flip bit here (will not be used)
ldy Block_SprDataOffset,x ;get sprite data offset
ldx #$00 ;reset X for use as offset to tile data
DBlkLoop: lda DefaultBlockObjTiles,x ;get left tile number
sta $00 ;set here
lda DefaultBlockObjTiles+1,x ;get right tile number
jsr DrawOneSpriteRow ;do sub to write tile numbers to first row of sprites
cpx #$04 ;check incremented offset
bne DBlkLoop ;and loop back until all four sprites are done
ldx ObjectOffset ;get block object offset
ldy Block_SprDataOffset,x ;get sprite data offset
lda AreaType
cmp #$01 ;check for ground level type area
beq ChkRep ;if found, branch to next part
lda #$86
sta Sprite_Tilenumber,y ;otherwise remove brick tiles with lines
sta Sprite_Tilenumber+4,y ;and replace then with lineless brick tiles
ChkRep: lda Block_Metatile,x ;check replacement metatile
cmp #$c4 ;if not used block metatile, then
bne BlkOffscr ;branch ahead to use current graphics
lda #$87 ;set A for used block tile
iny ;increment Y to write to tile bytes
jsr DumpFourSpr ;do sub to dump into all four sprites
dey ;return Y to original offset
lda #$03 ;set palette bits
ldx AreaType
dex ;check for ground level type area again
beq SetBFlip ;if found, use current palette bits
lsr ;otherwise set to $01
SetBFlip: ldx ObjectOffset ;put block object offset back in X
sta Sprite_Attributes,y ;store attribute byte as-is in first sprite
ora #%01000000
sta Sprite_Attributes+4,y ;set horizontal flip bit for second sprite
ora #%10000000
sta Sprite_Attributes+12,y ;set both flip bits for fourth sprite
and #%10000011
sta Sprite_Attributes+8,y ;set vertical flip bit for third sprite
BlkOffscr: lda Block_OffscreenBits ;get offscreen bits for block object
pha ;save to stack
and #%00000100 ;check to see if d2 in offscreen bits are set
beq PullOfsB ;if not set, branch, otherwise move sprites offscreen
lda #$f8 ;move offscreen two OAMs
sta Sprite_Y_Position+4,y ;on the right side
sta Sprite_Y_Position+12,y
PullOfsB: pla ;pull offscreen bits from stack
ChkLeftCo: and #%00001000 ;check to see if d3 in offscreen bits are set
beq ExDBlk ;if not set, branch, otherwise move sprites offscreen
MoveColOffscreen:
lda #$f8 ;move offscreen two OAMs
sta Sprite_Y_Position,y ;on the left side (or two rows of enemy on either side
sta Sprite_Y_Position+8,y ;if branched here from enemy graphics handler)
ExDBlk: rts
;-------------------------------------------------------------------------------------
;$00 - used to hold palette bits for attribute byte or relative X position
DrawBrickChunks:
lda #$02 ;set palette bits here
sta $00
lda #$75 ;set tile number for ball (something residual, likely)
ldy GameEngineSubroutine
cpy #$05 ;if end-of-level routine running,
beq DChunks ;use palette and tile number assigned
lda #$03 ;otherwise set different palette bits
sta $00
lda #$84 ;and set tile number for brick chunks
DChunks: ldy Block_SprDataOffset,x ;get OAM data offset
iny ;increment to start with tile bytes in OAM
jsr DumpFourSpr ;do sub to dump tile number into all four sprites
lda FrameCounter ;get frame counter
asl
asl
asl ;move low nybble to high
asl
and #$c0 ;get what was originally d3-d2 of low nybble
ora $00 ;add palette bits
iny ;increment offset for attribute bytes
jsr DumpFourSpr ;do sub to dump attribute data into all four sprites
dey
dey ;decrement offset to Y coordinate
lda Block_Rel_YPos ;get first block object's relative vertical coordinate
jsr DumpTwoSpr ;do sub to dump current Y coordinate into two sprites
lda Block_Rel_XPos ;get first block object's relative horizontal coordinate
sta Sprite_X_Position,y ;save into X coordinate of first sprite
lda Block_Orig_XPos,x ;get original horizontal coordinate
sec
sbc ScreenLeft_X_Pos ;subtract coordinate of left side from original coordinate
sta $00 ;store result as relative horizontal coordinate of original
sec
sbc Block_Rel_XPos ;get difference of relative positions of original - current
adc $00 ;add original relative position to result
adc #$06 ;plus 6 pixels to position second brick chunk correctly
sta Sprite_X_Position+4,y ;save into X coordinate of second sprite
lda Block_Rel_YPos+1 ;get second block object's relative vertical coordinate
sta Sprite_Y_Position+8,y
sta Sprite_Y_Position+12,y ;dump into Y coordinates of third and fourth sprites
lda Block_Rel_XPos+1 ;get second block object's relative horizontal coordinate
sta Sprite_X_Position+8,y ;save into X coordinate of third sprite
lda $00 ;use original relative horizontal position
sec
sbc Block_Rel_XPos+1 ;get difference of relative positions of original - current
adc $00 ;add original relative position to result
adc #$06 ;plus 6 pixels to position fourth brick chunk correctly
sta Sprite_X_Position+12,y ;save into X coordinate of fourth sprite
lda Block_OffscreenBits ;get offscreen bits for block object
jsr ChkLeftCo ;do sub to move left half of sprites offscreen if necessary
lda Block_OffscreenBits ;get offscreen bits again
asl ;shift d7 into carry
bcc ChnkOfs ;if d7 not set, branch to last part
lda #$f8
jsr DumpTwoSpr ;otherwise move top sprites offscreen
ChnkOfs: lda $00 ;if relative position on left side of screen,
bpl ExBCDr ;go ahead and leave
lda Sprite_X_Position,y ;otherwise compare left-side X coordinate
cmp Sprite_X_Position+4,y ;to right-side X coordinate
bcc ExBCDr ;branch to leave if less
lda #$f8 ;otherwise move right half of sprites offscreen
sta Sprite_Y_Position+4,y
sta Sprite_Y_Position+12,y
ExBCDr: rts ;leave
;-------------------------------------------------------------------------------------
DrawFireball:
ldy FBall_SprDataOffset,x ;get fireball's sprite data offset
lda Fireball_Rel_YPos ;get relative vertical coordinate
sta Sprite_Y_Position,y ;store as sprite Y coordinate
lda Fireball_Rel_XPos ;get relative horizontal coordinate
sta Sprite_X_Position,y ;store as sprite X coordinate, then do shared code
DrawFirebar:
lda FrameCounter ;get frame counter
lsr ;divide by four
lsr
pha ;save result to stack
and #$01 ;mask out all but last bit
eor #$64 ;set either tile $64 or $65 as fireball tile
sta Sprite_Tilenumber,y ;thus tile changes every four frames
pla ;get from stack
lsr ;divide by four again
lsr
lda #$02 ;load value $02 to set palette in attrib byte
bcc FireA ;if last bit shifted out was not set, skip this
ora #%11000000 ;otherwise flip both ways every eight frames
FireA: sta Sprite_Attributes,y ;store attribute byte and leave
rts
;-------------------------------------------------------------------------------------
ExplosionTiles:
.db $68, $67, $66
DrawExplosion_Fireball:
ldy Alt_SprDataOffset,x ;get OAM data offset of alternate sort for fireball's explosion
lda Fireball_State,x ;load fireball state
inc Fireball_State,x ;increment state for next frame
lsr ;divide by 2
and #%00000111 ;mask out all but d3-d1
cmp #$03 ;check to see if time to kill fireball
bcs KillFireBall ;branch if so, otherwise continue to draw explosion
DrawExplosion_Fireworks:
tax ;use whatever's in A for offset
lda ExplosionTiles,x ;get tile number using offset
iny ;increment Y (contains sprite data offset)
jsr DumpFourSpr ;and dump into tile number part of sprite data
dey ;decrement Y so we have the proper offset again
ldx ObjectOffset ;return enemy object buffer offset to X
lda Fireball_Rel_YPos ;get relative vertical coordinate
sec ;subtract four pixels vertically
sbc #$04 ;for first and third sprites
sta Sprite_Y_Position,y
sta Sprite_Y_Position+8,y
clc ;add eight pixels vertically
adc #$08 ;for second and fourth sprites
sta Sprite_Y_Position+4,y
sta Sprite_Y_Position+12,y
lda Fireball_Rel_XPos ;get relative horizontal coordinate
sec ;subtract four pixels horizontally
sbc #$04 ;for first and second sprites
sta Sprite_X_Position,y
sta Sprite_X_Position+4,y
clc ;add eight pixels horizontally
adc #$08 ;for third and fourth sprites
sta Sprite_X_Position+8,y
sta Sprite_X_Position+12,y
lda #$02 ;set palette attributes for all sprites, but
sta Sprite_Attributes,y ;set no flip at all for first sprite
lda #$82
sta Sprite_Attributes+4,y ;set vertical flip for second sprite
lda #$42
sta Sprite_Attributes+8,y ;set horizontal flip for third sprite
lda #$c2
sta Sprite_Attributes+12,y ;set both flips for fourth sprite
rts ;we are done
KillFireBall:
lda #$00 ;clear fireball state to kill it
sta Fireball_State,x
rts
;-------------------------------------------------------------------------------------
DrawSmallPlatform:
ldy Enemy_SprDataOffset,x ;get OAM data offset
lda #$5b ;load tile number for small platforms
iny ;increment offset for tile numbers
jsr DumpSixSpr ;dump tile number into all six sprites
iny ;increment offset for attributes
lda #$02 ;load palette controls
jsr DumpSixSpr ;dump attributes into all six sprites
dey ;decrement for original offset
dey
lda Enemy_Rel_XPos ;get relative horizontal coordinate
sta Sprite_X_Position,y
sta Sprite_X_Position+12,y ;dump as X coordinate into first and fourth sprites
clc
adc #$08 ;add eight pixels
sta Sprite_X_Position+4,y ;dump into second and fifth sprites
sta Sprite_X_Position+16,y
clc
adc #$08 ;add eight more pixels
sta Sprite_X_Position+8,y ;dump into third and sixth sprites
sta Sprite_X_Position+20,y
lda Enemy_Y_Position,x ;get vertical coordinate
tax
pha ;save to stack
cpx #$20 ;if vertical coordinate below status bar,
bcs TopSP ;do not mess with it
lda #$f8 ;otherwise move first three sprites offscreen
TopSP: jsr DumpThreeSpr ;dump vertical coordinate into Y coordinates
pla ;pull from stack
clc
adc #$80 ;add 128 pixels
tax
cpx #$20 ;if below status bar (taking wrap into account)
bcs BotSP ;then do not change altered coordinate
lda #$f8 ;otherwise move last three sprites offscreen
BotSP: sta Sprite_Y_Position+12,y ;dump vertical coordinate + 128 pixels
sta Sprite_Y_Position+16,y ;into Y coordinates
sta Sprite_Y_Position+20,y
lda Enemy_OffscreenBits ;get offscreen bits
pha ;save to stack
and #%00001000 ;check d3
beq SOfs
lda #$f8 ;if d3 was set, move first and
sta Sprite_Y_Position,y ;fourth sprites offscreen
sta Sprite_Y_Position+12,y
SOfs: pla ;move out and back into stack
pha
and #%00000100 ;check d2
beq SOfs2
lda #$f8 ;if d2 was set, move second and
sta Sprite_Y_Position+4,y ;fifth sprites offscreen
sta Sprite_Y_Position+16,y
SOfs2: pla ;get from stack
and #%00000010 ;check d1
beq ExSPl
lda #$f8 ;if d1 was set, move third and
sta Sprite_Y_Position+8,y ;sixth sprites offscreen
sta Sprite_Y_Position+20,y
ExSPl: ldx ObjectOffset ;get enemy object offset and leave
rts
;-------------------------------------------------------------------------------------
DrawBubble:
ldy Player_Y_HighPos ;if player's vertical high position
dey ;not within screen, skip all of this
bne ExDBub
lda Bubble_OffscreenBits ;check air bubble's offscreen bits
and #%00001000
bne ExDBub ;if bit set, branch to leave
ldy Bubble_SprDataOffset,x ;get air bubble's OAM data offset
lda Bubble_Rel_XPos ;get relative horizontal coordinate
sta Sprite_X_Position,y ;store as X coordinate here
lda Bubble_Rel_YPos ;get relative vertical coordinate
sta Sprite_Y_Position,y ;store as Y coordinate here
lda #$74
sta Sprite_Tilenumber,y ;put air bubble tile into OAM data
lda #$02
sta Sprite_Attributes,y ;set attribute byte
ExDBub: rts ;leave
;-------------------------------------------------------------------------------------
;$00 - used to store player's vertical offscreen bits
PlayerGfxTblOffsets:
.db $20, $28, $c8, $18, $00, $40, $50, $58
.db $80, $88, $b8, $78, $60, $a0, $b0, $b8
;tiles arranged in order, 2 tiles per row, top to bottom
PlayerGraphicsTable:
;big player table
.db $00, $01, $02, $03, $04, $05, $06, $07 ;walking frame 1
.db $08, $09, $0a, $0b, $0c, $0d, $0e, $0f ; frame 2
.db $10, $11, $12, $13, $14, $15, $16, $17 ; frame 3
.db $18, $19, $1a, $1b, $1c, $1d, $1e, $1f ;skidding
.db $20, $21, $22, $23, $24, $25, $26, $27 ;jumping
.db $08, $09, $28, $29, $2a, $2b, $2c, $2d ;swimming frame 1
.db $08, $09, $0a, $0b, $0c, $30, $2c, $2d ; frame 2
.db $08, $09, $0a, $0b, $2e, $2f, $2c, $2d ; frame 3
.db $08, $09, $28, $29, $2a, $2b, $5c, $5d ;climbing frame 1
.db $08, $09, $0a, $0b, $0c, $0d, $5e, $5f ; frame 2
.db $fc, $fc, $08, $09, $58, $59, $5a, $5a ;crouching
.db $08, $09, $28, $29, $2a, $2b, $0e, $0f ;fireball throwing
;small player table
.db $fc, $fc, $fc, $fc, $32, $33, $34, $35 ;walking frame 1
.db $fc, $fc, $fc, $fc, $36, $37, $38, $39 ; frame 2
.db $fc, $fc, $fc, $fc, $3a, $37, $3b, $3c ; frame 3
.db $fc, $fc, $fc, $fc, $3d, $3e, $3f, $40 ;skidding
.db $fc, $fc, $fc, $fc, $32, $41, $42, $43 ;jumping
.db $fc, $fc, $fc, $fc, $32, $33, $44, $45 ;swimming frame 1
.db $fc, $fc, $fc, $fc, $32, $33, $44, $47 ; frame 2
.db $fc, $fc, $fc, $fc, $32, $33, $48, $49 ; frame 3
.db $fc, $fc, $fc, $fc, $32, $33, $90, $91 ;climbing frame 1
.db $fc, $fc, $fc, $fc, $3a, $37, $92, $93 ; frame 2
.db $fc, $fc, $fc, $fc, $9e, $9e, $9f, $9f ;killed
;used by both player sizes
.db $fc, $fc, $fc, $fc, $3a, $37, $4f, $4f ;small player standing
.db $fc, $fc, $00, $01, $4c, $4d, $4e, $4e ;intermediate grow frame
.db $00, $01, $4c, $4d, $4a, $4a, $4b, $4b ;big player standing
SwimKickTileNum:
.db $31, $46
PlayerGfxHandler:
lda InjuryTimer ;if player's injured invincibility timer
beq CntPl ;not set, skip checkpoint and continue code
lda FrameCounter
lsr ;otherwise check frame counter and branch
bcs ExPGH ;to leave on every other frame (when d0 is set)
CntPl: lda GameEngineSubroutine ;if executing specific game engine routine,
cmp #$0b ;branch ahead to some other part
beq PlayerKilled
lda PlayerChangeSizeFlag ;if grow/shrink flag set
bne DoChangeSize ;then branch to some other code
ldy SwimmingFlag ;if swimming flag set, branch to
beq FindPlayerAction ;different part, do not return
lda Player_State
cmp #$00 ;if player status normal,
beq FindPlayerAction ;branch and do not return
jsr FindPlayerAction ;otherwise jump and return
lda FrameCounter
and #%00000100 ;check frame counter for d2 set (8 frames every
bne ExPGH ;eighth frame), and branch if set to leave
tax ;initialize X to zero
ldy Player_SprDataOffset ;get player sprite data offset
lda PlayerFacingDir ;get player's facing direction
lsr
bcs SwimKT ;if player facing to the right, use current offset
iny
iny ;otherwise move to next OAM data
iny
iny
SwimKT: lda PlayerSize ;check player's size
beq BigKTS ;if big, use first tile
lda Sprite_Tilenumber+24,y ;check tile number of seventh/eighth sprite
cmp SwimTileRepOffset ;against tile number in player graphics table
beq ExPGH ;if spr7/spr8 tile number = value, branch to leave
inx ;otherwise increment X for second tile
BigKTS: lda SwimKickTileNum,x ;overwrite tile number in sprite 7/8
sta Sprite_Tilenumber+24,y ;to animate player's feet when swimming
ExPGH: rts ;then leave
FindPlayerAction:
jsr ProcessPlayerAction ;find proper offset to graphics table by player's actions
jmp PlayerGfxProcessing ;draw player, then process for fireball throwing
DoChangeSize:
jsr HandleChangeSize ;find proper offset to graphics table for grow/shrink
jmp PlayerGfxProcessing ;draw player, then process for fireball throwing
PlayerKilled:
ldy #$0e ;load offset for player killed
lda PlayerGfxTblOffsets,y ;get offset to graphics table
PlayerGfxProcessing:
sta PlayerGfxOffset ;store offset to graphics table here
lda #$04
jsr RenderPlayerSub ;draw player based on offset loaded
jsr ChkForPlayerAttrib ;set horizontal flip bits as necessary
lda FireballThrowingTimer
beq PlayerOffscreenChk ;if fireball throw timer not set, skip to the end
ldy #$00 ;set value to initialize by default
lda PlayerAnimTimer ;get animation frame timer
cmp FireballThrowingTimer ;compare to fireball throw timer
sty FireballThrowingTimer ;initialize fireball throw timer
bcs PlayerOffscreenChk ;if animation frame timer => fireball throw timer skip to end
sta FireballThrowingTimer ;otherwise store animation timer into fireball throw timer
ldy #$07 ;load offset for throwing
lda PlayerGfxTblOffsets,y ;get offset to graphics table
sta PlayerGfxOffset ;store it for use later
ldy #$04 ;set to update four sprite rows by default
lda Player_X_Speed
ora Left_Right_Buttons ;check for horizontal speed or left/right button press
beq SUpdR ;if no speed or button press, branch using set value in Y
dey ;otherwise set to update only three sprite rows
SUpdR: tya ;save in A for use
jsr RenderPlayerSub ;in sub, draw player object again
PlayerOffscreenChk:
lda Player_OffscreenBits ;get player's offscreen bits
lsr
lsr ;move vertical bits to low nybble
lsr
lsr
sta $00 ;store here
ldx #$03 ;check all four rows of player sprites
lda Player_SprDataOffset ;get player's sprite data offset
clc
adc #$18 ;add 24 bytes to start at bottom row
tay ;set as offset here
PROfsLoop: lda #$f8 ;load offscreen Y coordinate just in case
lsr $00 ;shift bit into carry
bcc NPROffscr ;if bit not set, skip, do not move sprites
jsr DumpTwoSpr ;otherwise dump offscreen Y coordinate into sprite data
NPROffscr: tya
sec ;subtract eight bytes to do
sbc #$08 ;next row up
tay
dex ;decrement row counter
bpl PROfsLoop ;do this until all sprite rows are checked
rts ;then we are done!
;-------------------------------------------------------------------------------------
IntermediatePlayerData:
.db $58, $01, $00, $60, $ff, $04
DrawPlayer_Intermediate:
ldx #$05 ;store data into zero page memory
PIntLoop: lda IntermediatePlayerData,x ;load data to display player as he always
sta $02,x ;appears on world/lives display
dex
bpl PIntLoop ;do this until all data is loaded
ldx #$b8 ;load offset for small standing
ldy #$04 ;load sprite data offset
jsr DrawPlayerLoop ;draw player accordingly
lda Sprite_Attributes+36 ;get empty sprite attributes
ora #%01000000 ;set horizontal flip bit for bottom-right sprite
sta Sprite_Attributes+32 ;store and leave
rts
;-------------------------------------------------------------------------------------
;$00-$01 - used to hold tile numbers, $00 also used to hold upper extent of animation frames
;$02 - vertical position
;$03 - facing direction, used as horizontal flip control
;$04 - attributes
;$05 - horizontal position
;$07 - number of rows to draw
;these also used in IntermediatePlayerData
RenderPlayerSub:
sta $07 ;store number of rows of sprites to draw
lda Player_Rel_XPos
sta Player_Pos_ForScroll ;store player's relative horizontal position
sta $05 ;store it here also
lda Player_Rel_YPos
sta $02 ;store player's vertical position
lda PlayerFacingDir
sta $03 ;store player's facing direction
lda Player_SprAttrib
sta $04 ;store player's sprite attributes
ldx PlayerGfxOffset ;load graphics table offset
ldy Player_SprDataOffset ;get player's sprite data offset
DrawPlayerLoop:
lda PlayerGraphicsTable,x ;load player's left side
sta $00
lda PlayerGraphicsTable+1,x ;now load right side
jsr DrawOneSpriteRow
dec $07 ;decrement rows of sprites to draw
bne DrawPlayerLoop ;do this until all rows are drawn
rts
ProcessPlayerAction:
lda Player_State ;get player's state
cmp #$03
beq ActionClimbing ;if climbing, branch here
cmp #$02
beq ActionFalling ;if falling, branch here
cmp #$01
bne ProcOnGroundActs ;if not jumping, branch here
lda SwimmingFlag
bne ActionSwimming ;if swimming flag set, branch elsewhere
ldy #$06 ;load offset for crouching
lda CrouchingFlag ;get crouching flag
bne NonAnimatedActs ;if set, branch to get offset for graphics table
ldy #$00 ;otherwise load offset for jumping
jmp NonAnimatedActs ;go to get offset to graphics table
ProcOnGroundActs:
ldy #$06 ;load offset for crouching
lda CrouchingFlag ;get crouching flag
bne NonAnimatedActs ;if set, branch to get offset for graphics table
ldy #$02 ;load offset for standing
lda Player_X_Speed ;check player's horizontal speed
ora Left_Right_Buttons ;and left/right controller bits
beq NonAnimatedActs ;if no speed or buttons pressed, use standing offset
lda Player_XSpeedAbsolute ;load walking/running speed
cmp #$09
bcc ActionWalkRun ;if less than a certain amount, branch, too slow to skid
lda Player_MovingDir ;otherwise check to see if moving direction
and PlayerFacingDir ;and facing direction are the same
bne ActionWalkRun ;if moving direction = facing direction, branch, don't skid
iny ;otherwise increment to skid offset ($03)
NonAnimatedActs:
jsr GetGfxOffsetAdder ;do a sub here to get offset adder for graphics table
lda #$00
sta PlayerAnimCtrl ;initialize animation frame control
lda PlayerGfxTblOffsets,y ;load offset to graphics table using size as offset
rts
ActionFalling:
ldy #$04 ;load offset for walking/running
jsr GetGfxOffsetAdder ;get offset to graphics table
jmp GetCurrentAnimOffset ;execute instructions for falling state
ActionWalkRun:
ldy #$04 ;load offset for walking/running
jsr GetGfxOffsetAdder ;get offset to graphics table
jmp FourFrameExtent ;execute instructions for normal state
ActionClimbing:
ldy #$05 ;load offset for climbing
lda Player_Y_Speed ;check player's vertical speed
beq NonAnimatedActs ;if no speed, branch, use offset as-is
jsr GetGfxOffsetAdder ;otherwise get offset for graphics table
jmp ThreeFrameExtent ;then skip ahead to more code
ActionSwimming:
ldy #$01 ;load offset for swimming
jsr GetGfxOffsetAdder
lda JumpSwimTimer ;check jump/swim timer
ora PlayerAnimCtrl ;and animation frame control
bne FourFrameExtent ;if any one of these set, branch ahead
lda A_B_Buttons
asl ;check for A button pressed
bcs FourFrameExtent ;branch to same place if A button pressed
GetCurrentAnimOffset:
lda PlayerAnimCtrl ;get animation frame control
jmp GetOffsetFromAnimCtrl ;jump to get proper offset to graphics table
FourFrameExtent:
lda #$03 ;load upper extent for frame control
jmp AnimationControl ;jump to get offset and animate player object
ThreeFrameExtent:
lda #$02 ;load upper extent for frame control for climbing
AnimationControl:
sta $00 ;store upper extent here
jsr GetCurrentAnimOffset ;get proper offset to graphics table
pha ;save offset to stack
lda PlayerAnimTimer ;load animation frame timer
bne ExAnimC ;branch if not expired
lda PlayerAnimTimerSet ;get animation frame timer amount
sta PlayerAnimTimer ;and set timer accordingly
lda PlayerAnimCtrl
clc ;add one to animation frame control
adc #$01
cmp $00 ;compare to upper extent
bcc SetAnimC ;if frame control + 1 < upper extent, use as next
lda #$00 ;otherwise initialize frame control
SetAnimC: sta PlayerAnimCtrl ;store as new animation frame control
ExAnimC: pla ;get offset to graphics table from stack and leave
rts
GetGfxOffsetAdder:
lda PlayerSize ;get player's size
beq SzOfs ;if player big, use current offset as-is
tya ;for big player
clc ;otherwise add eight bytes to offset
adc #$08 ;for small player
tay
SzOfs: rts ;go back
ChangeSizeOffsetAdder:
.db $00, $01, $00, $01, $00, $01, $02, $00, $01, $02
.db $02, $00, $02, $00, $02, $00, $02, $00, $02, $00
HandleChangeSize:
ldy PlayerAnimCtrl ;get animation frame control
lda FrameCounter
and #%00000011 ;get frame counter and execute this code every
bne GorSLog ;fourth frame, otherwise branch ahead
iny ;increment frame control
cpy #$0a ;check for preset upper extent
bcc CSzNext ;if not there yet, skip ahead to use
ldy #$00 ;otherwise initialize both grow/shrink flag
sty PlayerChangeSizeFlag ;and animation frame control
CSzNext: sty PlayerAnimCtrl ;store proper frame control
GorSLog: lda PlayerSize ;get player's size
bne ShrinkPlayer ;if player small, skip ahead to next part
lda ChangeSizeOffsetAdder,y ;get offset adder based on frame control as offset
ldy #$0f ;load offset for player growing
GetOffsetFromAnimCtrl:
asl ;multiply animation frame control
asl ;by eight to get proper amount
asl ;to add to our offset
adc PlayerGfxTblOffsets,y ;add to offset to graphics table
rts ;and return with result in A
ShrinkPlayer:
tya ;add ten bytes to frame control as offset
clc
adc #$0a ;this thing apparently uses two of the swimming frames
tax ;to draw the player shrinking
ldy #$09 ;load offset for small player swimming
lda ChangeSizeOffsetAdder,x ;get what would normally be offset adder
bne ShrPlF ;and branch to use offset if nonzero
ldy #$01 ;otherwise load offset for big player swimming
ShrPlF: lda PlayerGfxTblOffsets,y ;get offset to graphics table based on offset loaded
rts ;and leave
ChkForPlayerAttrib:
ldy Player_SprDataOffset ;get sprite data offset
lda GameEngineSubroutine
cmp #$0b ;if executing specific game engine routine,
beq KilledAtt ;branch to change third and fourth row OAM attributes
lda PlayerGfxOffset ;get graphics table offset
cmp #$50
beq C_S_IGAtt ;if crouch offset, either standing offset,
cmp #$b8 ;or intermediate growing offset,
beq C_S_IGAtt ;go ahead and execute code to change
cmp #$c0 ;fourth row OAM attributes only
beq C_S_IGAtt
cmp #$c8
bne ExPlyrAt ;if none of these, branch to leave
KilledAtt: lda Sprite_Attributes+16,y
and #%00111111 ;mask out horizontal and vertical flip bits
sta Sprite_Attributes+16,y ;for third row sprites and save
lda Sprite_Attributes+20,y
and #%00111111
ora #%01000000 ;set horizontal flip bit for second
sta Sprite_Attributes+20,y ;sprite in the third row
C_S_IGAtt: lda Sprite_Attributes+24,y
and #%00111111 ;mask out horizontal and vertical flip bits
sta Sprite_Attributes+24,y ;for fourth row sprites and save
lda Sprite_Attributes+28,y
and #%00111111
ora #%01000000 ;set horizontal flip bit for second
sta Sprite_Attributes+28,y ;sprite in the fourth row
ExPlyrAt: rts ;leave
;-------------------------------------------------------------------------------------
;$00 - used in adding to get proper offset
RelativePlayerPosition:
ldx #$00 ;set offsets for relative cooordinates
ldy #$00 ;routine to correspond to player object
jmp RelWOfs ;get the coordinates
RelativeBubblePosition:
ldy #$01 ;set for air bubble offsets
jsr GetProperObjOffset ;modify X to get proper air bubble offset
ldy #$03
jmp RelWOfs ;get the coordinates
RelativeFireballPosition:
ldy #$00 ;set for fireball offsets
jsr GetProperObjOffset ;modify X to get proper fireball offset
ldy #$02
RelWOfs: jsr GetObjRelativePosition ;get the coordinates
ldx ObjectOffset ;return original offset
rts ;leave
RelativeMiscPosition:
ldy #$02 ;set for misc object offsets
jsr GetProperObjOffset ;modify X to get proper misc object offset
ldy #$06
jmp RelWOfs ;get the coordinates
RelativeEnemyPosition:
lda #$01 ;get coordinates of enemy object
ldy #$01 ;relative to the screen
jmp VariableObjOfsRelPos
RelativeBlockPosition:
lda #$09 ;get coordinates of one block object
ldy #$04 ;relative to the screen
jsr VariableObjOfsRelPos
inx ;adjust offset for other block object if any
inx
lda #$09
iny ;adjust other and get coordinates for other one
VariableObjOfsRelPos:
stx $00 ;store value to add to A here
clc
adc $00 ;add A to value stored
tax ;use as enemy offset
jsr GetObjRelativePosition
ldx ObjectOffset ;reload old object offset and leave
rts
GetObjRelativePosition:
lda SprObject_Y_Position,x ;load vertical coordinate low
sta SprObject_Rel_YPos,y ;store here
lda SprObject_X_Position,x ;load horizontal coordinate
sec ;subtract left edge coordinate
sbc ScreenLeft_X_Pos
sta SprObject_Rel_XPos,y ;store result here
rts
;-------------------------------------------------------------------------------------
;$00 - used as temp variable to hold offscreen bits
GetPlayerOffscreenBits:
ldx #$00 ;set offsets for player-specific variables
ldy #$00 ;and get offscreen information about player
jmp GetOffScreenBitsSet
GetFireballOffscreenBits:
ldy #$00 ;set for fireball offsets
jsr GetProperObjOffset ;modify X to get proper fireball offset
ldy #$02 ;set other offset for fireball's offscreen bits
jmp GetOffScreenBitsSet ;and get offscreen information about fireball
GetBubbleOffscreenBits:
ldy #$01 ;set for air bubble offsets
jsr GetProperObjOffset ;modify X to get proper air bubble offset
ldy #$03 ;set other offset for airbubble's offscreen bits
jmp GetOffScreenBitsSet ;and get offscreen information about air bubble
GetMiscOffscreenBits:
ldy #$02 ;set for misc object offsets
jsr GetProperObjOffset ;modify X to get proper misc object offset
ldy #$06 ;set other offset for misc object's offscreen bits
jmp GetOffScreenBitsSet ;and get offscreen information about misc object
ObjOffsetData:
.db $07, $16, $0d
GetProperObjOffset:
txa ;move offset to A
clc
adc ObjOffsetData,y ;add amount of bytes to offset depending on setting in Y
tax ;put back in X and leave
rts
GetEnemyOffscreenBits:
lda #$01 ;set A to add 1 byte in order to get enemy offset
ldy #$01 ;set Y to put offscreen bits in Enemy_OffscreenBits
jmp SetOffscrBitsOffset
GetBlockOffscreenBits:
lda #$09 ;set A to add 9 bytes in order to get block obj offset
ldy #$04 ;set Y to put offscreen bits in Block_OffscreenBits
SetOffscrBitsOffset:
stx $00
clc ;add contents of X to A to get
adc $00 ;appropriate offset, then give back to X
tax
GetOffScreenBitsSet:
tya ;save offscreen bits offset to stack for now
pha
jsr RunOffscrBitsSubs
asl ;move low nybble to high nybble
asl
asl
asl
ora $00 ;mask together with previously saved low nybble
sta $00 ;store both here
pla ;get offscreen bits offset from stack
tay
lda $00 ;get value here and store elsewhere
sta SprObject_OffscrBits,y
ldx ObjectOffset
rts
RunOffscrBitsSubs:
jsr GetXOffscreenBits ;do subroutine here
lsr ;move high nybble to low
lsr
lsr
lsr
sta $00 ;store here
jmp GetYOffscreenBits
;--------------------------------
;(these apply to these three subsections)
;$04 - used to store proper offset
;$05 - used as adder in DividePDiff
;$06 - used to store preset value used to compare to pixel difference in $07
;$07 - used to store difference between coordinates of object and screen edges
XOffscreenBitsData:
.db $7f, $3f, $1f, $0f, $07, $03, $01, $00
.db $80, $c0, $e0, $f0, $f8, $fc, $fe, $ff
DefaultXOnscreenOfs:
.db $07, $0f, $07
GetXOffscreenBits:
stx $04 ;save position in buffer to here
ldy #$01 ;start with right side of screen
XOfsLoop: lda ScreenEdge_X_Pos,y ;get pixel coordinate of edge
sec ;get difference between pixel coordinate of edge
sbc SprObject_X_Position,x ;and pixel coordinate of object position
sta $07 ;store here
lda ScreenEdge_PageLoc,y ;get page location of edge
sbc SprObject_PageLoc,x ;subtract from page location of object position
ldx DefaultXOnscreenOfs,y ;load offset value here
cmp #$00
bmi XLdBData ;if beyond right edge or in front of left edge, branch
ldx DefaultXOnscreenOfs+1,y ;if not, load alternate offset value here
cmp #$01
bpl XLdBData ;if one page or more to the left of either edge, branch
lda #$38 ;if no branching, load value here and store
sta $06
lda #$08 ;load some other value and execute subroutine
jsr DividePDiff
XLdBData: lda XOffscreenBitsData,x ;get bits here
ldx $04 ;reobtain position in buffer
cmp #$00 ;if bits not zero, branch to leave
bne ExXOfsBS
dey ;otherwise, do left side of screen now
bpl XOfsLoop ;branch if not already done with left side
ExXOfsBS: rts
;--------------------------------
YOffscreenBitsData:
.db $00, $08, $0c, $0e
.db $0f, $07, $03, $01
.db $00
DefaultYOnscreenOfs:
.db $04, $00, $04
HighPosUnitData:
.db $ff, $00
GetYOffscreenBits:
stx $04 ;save position in buffer to here
ldy #$01 ;start with top of screen
YOfsLoop: lda HighPosUnitData,y ;load coordinate for edge of vertical unit
sec
sbc SprObject_Y_Position,x ;subtract from vertical coordinate of object
sta $07 ;store here
lda #$01 ;subtract one from vertical high byte of object
sbc SprObject_Y_HighPos,x
ldx DefaultYOnscreenOfs,y ;load offset value here
cmp #$00
bmi YLdBData ;if under top of the screen or beyond bottom, branch
ldx DefaultYOnscreenOfs+1,y ;if not, load alternate offset value here
cmp #$01
bpl YLdBData ;if one vertical unit or more above the screen, branch
lda #$20 ;if no branching, load value here and store
sta $06
lda #$04 ;load some other value and execute subroutine
jsr DividePDiff
YLdBData: lda YOffscreenBitsData,x ;get offscreen data bits using offset
ldx $04 ;reobtain position in buffer
cmp #$00
bne ExYOfsBS ;if bits not zero, branch to leave
dey ;otherwise, do bottom of the screen now
bpl YOfsLoop
ExYOfsBS: rts
;--------------------------------
DividePDiff:
sta $05 ;store current value in A here
lda $07 ;get pixel difference
cmp $06 ;compare to preset value
bcs ExDivPD ;if pixel difference >= preset value, branch
lsr ;divide by eight
lsr
lsr
and #$07 ;mask out all but 3 LSB
cpy #$01 ;right side of the screen or top?
bcs SetOscrO ;if so, branch, use difference / 8 as offset
adc $05 ;if not, add value to difference / 8
SetOscrO: tax ;use as offset
ExDivPD: rts ;leave
;-------------------------------------------------------------------------------------
;$00-$01 - tile numbers
;$02 - Y coordinate
;$03 - flip control
;$04 - sprite attributes
;$05 - X coordinate
DrawSpriteObject:
lda $03 ;get saved flip control bits
lsr
lsr ;move d1 into carry
lda $00
bcc NoHFlip ;if d1 not set, branch
sta Sprite_Tilenumber+4,y ;store first tile into second sprite
lda $01 ;and second into first sprite
sta Sprite_Tilenumber,y
lda #$40 ;activate horizontal flip OAM attribute
bne SetHFAt ;and unconditionally branch
NoHFlip: sta Sprite_Tilenumber,y ;store first tile into first sprite
lda $01 ;and second into second sprite
sta Sprite_Tilenumber+4,y
lda #$00 ;clear bit for horizontal flip
SetHFAt: ora $04 ;add other OAM attributes if necessary
sta Sprite_Attributes,y ;store sprite attributes
sta Sprite_Attributes+4,y
lda $02 ;now the y coordinates
sta Sprite_Y_Position,y ;note because they are
sta Sprite_Y_Position+4,y ;side by side, they are the same
lda $05
sta Sprite_X_Position,y ;store x coordinate, then
clc ;add 8 pixels and store another to
adc #$08 ;put them side by side
sta Sprite_X_Position+4,y
lda $02 ;add eight pixels to the next y
clc ;coordinate
adc #$08
sta $02
tya ;add eight to the offset in Y to
clc ;move to the next two sprites
adc #$08
tay
inx ;increment offset to return it to the
inx ;routine that called this subroutine
rts
;-------------------------------------------------------------------------------------
;unused space
.db $ff, $ff, $ff, $ff, $ff, $ff
;-------------------------------------------------------------------------------------
SoundEngine:
lda OperMode ;are we in title screen mode?
bne SndOn
sta SND_MASTERCTRL_REG ;if so, disable sound and leave
rts
SndOn: lda #$ff
sta JOYPAD_PORT2 ;disable irqs and set frame counter mode???
lda #$0f
sta SND_MASTERCTRL_REG ;enable first four channels
lda PauseModeFlag ;is sound already in pause mode?
bne InPause
lda PauseSoundQueue ;if not, check pause sfx queue
cmp #$01
bne RunSoundSubroutines ;if queue is empty, skip pause mode routine
InPause: lda PauseSoundBuffer ;check pause sfx buffer
bne ContPau
lda PauseSoundQueue ;check pause queue
beq SkipSoundSubroutines
sta PauseSoundBuffer ;if queue full, store in buffer and activate
sta PauseModeFlag ;pause mode to interrupt game sounds
lda #$00 ;disable sound and clear sfx buffers
sta SND_MASTERCTRL_REG
sta Square1SoundBuffer
sta Square2SoundBuffer
sta NoiseSoundBuffer
lda #$0f
sta SND_MASTERCTRL_REG ;enable sound again
lda #$2a ;store length of sound in pause counter
sta Squ1_SfxLenCounter
PTone1F: lda #$44 ;play first tone
bne PTRegC ;unconditional branch
ContPau: lda Squ1_SfxLenCounter ;check pause length left
cmp #$24 ;time to play second?
beq PTone2F
cmp #$1e ;time to play first again?
beq PTone1F
cmp #$18 ;time to play second again?
bne DecPauC ;only load regs during times, otherwise skip
PTone2F: lda #$64 ;store reg contents and play the pause sfx
PTRegC: ldx #$84
ldy #$7f
jsr PlaySqu1Sfx
DecPauC: dec Squ1_SfxLenCounter ;decrement pause sfx counter
bne SkipSoundSubroutines
lda #$00 ;disable sound if in pause mode and
sta SND_MASTERCTRL_REG ;not currently playing the pause sfx
lda PauseSoundBuffer ;if no longer playing pause sfx, check to see
cmp #$02 ;if we need to be playing sound again
bne SkipPIn
lda #$00 ;clear pause mode to allow game sounds again
sta PauseModeFlag
SkipPIn: lda #$00 ;clear pause sfx buffer
sta PauseSoundBuffer
beq SkipSoundSubroutines
RunSoundSubroutines:
jsr Square1SfxHandler ;play sfx on square channel 1
jsr Square2SfxHandler ; '' '' '' square channel 2
jsr NoiseSfxHandler ; '' '' '' noise channel
jsr MusicHandler ;play music on all channels
lda #$00 ;clear the music queues
sta AreaMusicQueue
sta EventMusicQueue
SkipSoundSubroutines:
lda #$00 ;clear the sound effects queues
sta Square1SoundQueue
sta Square2SoundQueue
sta NoiseSoundQueue
sta PauseSoundQueue
ldy DAC_Counter ;load some sort of counter
lda AreaMusicBuffer
and #%00000011 ;check for specific music
beq NoIncDAC
inc DAC_Counter ;increment and check counter
cpy #$30
bcc StrWave ;if not there yet, just store it
NoIncDAC: tya
beq StrWave ;if we are at zero, do not decrement
dec DAC_Counter ;decrement counter
StrWave: sty SND_DELTA_REG+1 ;store into DMC load register (??)
rts ;we are done here
;--------------------------------
Dump_Squ1_Regs:
sty SND_SQUARE1_REG+1 ;dump the contents of X and Y into square 1's control regs
stx SND_SQUARE1_REG
rts
PlaySqu1Sfx:
jsr Dump_Squ1_Regs ;do sub to set ctrl regs for square 1, then set frequency regs
SetFreq_Squ1:
ldx #$00 ;set frequency reg offset for square 1 sound channel
Dump_Freq_Regs:
tay
lda FreqRegLookupTbl+1,y ;use previous contents of A for sound reg offset
beq NoTone ;if zero, then do not load
sta SND_REGISTER+2,x ;first byte goes into LSB of frequency divider
lda FreqRegLookupTbl,y ;second byte goes into 3 MSB plus extra bit for
ora #%00001000 ;length counter
sta SND_REGISTER+3,x
NoTone: rts
Dump_Sq2_Regs:
stx SND_SQUARE2_REG ;dump the contents of X and Y into square 2's control regs
sty SND_SQUARE2_REG+1
rts
PlaySqu2Sfx:
jsr Dump_Sq2_Regs ;do sub to set ctrl regs for square 2, then set frequency regs
SetFreq_Squ2:
ldx #$04 ;set frequency reg offset for square 2 sound channel
bne Dump_Freq_Regs ;unconditional branch
SetFreq_Tri:
ldx #$08 ;set frequency reg offset for triangle sound channel
bne Dump_Freq_Regs ;unconditional branch
;--------------------------------
SwimStompEnvelopeData:
.db $9f, $9b, $98, $96, $95, $94, $92, $90
.db $90, $9a, $97, $95, $93, $92
PlayFlagpoleSlide:
lda #$40 ;store length of flagpole sound
sta Squ1_SfxLenCounter
lda #$62 ;load part of reg contents for flagpole sound
jsr SetFreq_Squ1
ldx #$99 ;now load the rest
bne FPS2nd
PlaySmallJump:
lda #$26 ;branch here for small mario jumping sound
bne JumpRegContents
PlayBigJump:
lda #$18 ;branch here for big mario jumping sound
JumpRegContents:
ldx #$82 ;note that small and big jump borrow each others' reg contents
ldy #$a7 ;anyway, this loads the first part of mario's jumping sound
jsr PlaySqu1Sfx
lda #$28 ;store length of sfx for both jumping sounds
sta Squ1_SfxLenCounter ;then continue on here
ContinueSndJump:
lda Squ1_SfxLenCounter ;jumping sounds seem to be composed of three parts
cmp #$25 ;check for time to play second part yet
bne N2Prt
ldx #$5f ;load second part
ldy #$f6
bne DmpJpFPS ;unconditional branch
N2Prt: cmp #$20 ;check for third part
bne DecJpFPS
ldx #$48 ;load third part
FPS2nd: ldy #$bc ;the flagpole slide sound shares part of third part
DmpJpFPS: jsr Dump_Squ1_Regs
bne DecJpFPS ;unconditional branch outta here
PlayFireballThrow:
lda #$05
ldy #$99 ;load reg contents for fireball throw sound
bne Fthrow ;unconditional branch
PlayBump:
lda #$0a ;load length of sfx and reg contents for bump sound
ldy #$93
Fthrow: ldx #$9e ;the fireball sound shares reg contents with the bump sound
sta Squ1_SfxLenCounter
lda #$0c ;load offset for bump sound
jsr PlaySqu1Sfx
ContinueBumpThrow:
lda Squ1_SfxLenCounter ;check for second part of bump sound
cmp #$06
bne DecJpFPS
lda #$bb ;load second part directly
sta SND_SQUARE1_REG+1
DecJpFPS: bne BranchToDecLength1 ;unconditional branch
Square1SfxHandler:
ldy Square1SoundQueue ;check for sfx in queue
beq CheckSfx1Buffer
sty Square1SoundBuffer ;if found, put in buffer
bmi PlaySmallJump ;small jump
lsr Square1SoundQueue
bcs PlayBigJump ;big jump
lsr Square1SoundQueue
bcs PlayBump ;bump
lsr Square1SoundQueue
bcs PlaySwimStomp ;swim/stomp
lsr Square1SoundQueue
bcs PlaySmackEnemy ;smack enemy
lsr Square1SoundQueue
bcs PlayPipeDownInj ;pipedown/injury
lsr Square1SoundQueue
bcs PlayFireballThrow ;fireball throw
lsr Square1SoundQueue
bcs PlayFlagpoleSlide ;slide flagpole
CheckSfx1Buffer:
lda Square1SoundBuffer ;check for sfx in buffer
beq ExS1H ;if not found, exit sub
bmi ContinueSndJump ;small mario jump
lsr
bcs ContinueSndJump ;big mario jump
lsr
bcs ContinueBumpThrow ;bump
lsr
bcs ContinueSwimStomp ;swim/stomp
lsr
bcs ContinueSmackEnemy ;smack enemy
lsr
bcs ContinuePipeDownInj ;pipedown/injury
lsr
bcs ContinueBumpThrow ;fireball throw
lsr
bcs DecrementSfx1Length ;slide flagpole
ExS1H: rts
PlaySwimStomp:
lda #$0e ;store length of swim/stomp sound
sta Squ1_SfxLenCounter
ldy #$9c ;store reg contents for swim/stomp sound
ldx #$9e
lda #$26
jsr PlaySqu1Sfx
ContinueSwimStomp:
ldy Squ1_SfxLenCounter ;look up reg contents in data section based on
lda SwimStompEnvelopeData-1,y ;length of sound left, used to control sound's
sta SND_SQUARE1_REG ;envelope
cpy #$06
bne BranchToDecLength1
lda #$9e ;when the length counts down to a certain point, put this
sta SND_SQUARE1_REG+2 ;directly into the LSB of square 1's frequency divider
BranchToDecLength1:
bne DecrementSfx1Length ;unconditional branch (regardless of how we got here)
PlaySmackEnemy:
lda #$0e ;store length of smack enemy sound
ldy #$cb
ldx #$9f
sta Squ1_SfxLenCounter
lda #$28 ;store reg contents for smack enemy sound
jsr PlaySqu1Sfx
bne DecrementSfx1Length ;unconditional branch
ContinueSmackEnemy:
ldy Squ1_SfxLenCounter ;check about halfway through
cpy #$08
bne SmSpc
lda #$a0 ;if we're at the about-halfway point, make the second tone
sta SND_SQUARE1_REG+2 ;in the smack enemy sound
lda #$9f
bne SmTick
SmSpc: lda #$90 ;this creates spaces in the sound, giving it its distinct noise
SmTick: sta SND_SQUARE1_REG
DecrementSfx1Length:
dec Squ1_SfxLenCounter ;decrement length of sfx
bne ExSfx1
StopSquare1Sfx:
ldx #$00 ;if end of sfx reached, clear buffer
stx $f1 ;and stop making the sfx
ldx #$0e
stx SND_MASTERCTRL_REG
ldx #$0f
stx SND_MASTERCTRL_REG
ExSfx1: rts
PlayPipeDownInj:
lda #$2f ;load length of pipedown sound
sta Squ1_SfxLenCounter
ContinuePipeDownInj:
lda Squ1_SfxLenCounter ;some bitwise logic, forces the regs
lsr ;to be written to only during six specific times
bcs NoPDwnL ;during which d3 must be set and d1-0 must be clear
lsr
bcs NoPDwnL
and #%00000010
beq NoPDwnL
ldy #$91 ;and this is where it actually gets written in
ldx #$9a
lda #$44
jsr PlaySqu1Sfx
NoPDwnL: jmp DecrementSfx1Length
;--------------------------------
ExtraLifeFreqData:
.db $58, $02, $54, $56, $4e, $44
PowerUpGrabFreqData:
.db $4c, $52, $4c, $48, $3e, $36, $3e, $36, $30
.db $28, $4a, $50, $4a, $64, $3c, $32, $3c, $32
.db $2c, $24, $3a, $64, $3a, $34, $2c, $22, $2c
;residual frequency data
.db $22, $1c, $14
PUp_VGrow_FreqData:
.db $14, $04, $22, $24, $16, $04, $24, $26 ;used by both
.db $18, $04, $26, $28, $1a, $04, $28, $2a
.db $1c, $04, $2a, $2c, $1e, $04, $2c, $2e ;used by vinegrow
.db $20, $04, $2e, $30, $22, $04, $30, $32
PlayCoinGrab:
lda #$35 ;load length of coin grab sound
ldx #$8d ;and part of reg contents
bne CGrab_TTickRegL
PlayTimerTick:
lda #$06 ;load length of timer tick sound
ldx #$98 ;and part of reg contents
CGrab_TTickRegL:
sta Squ2_SfxLenCounter
ldy #$7f ;load the rest of reg contents
lda #$42 ;of coin grab and timer tick sound
jsr PlaySqu2Sfx
ContinueCGrabTTick:
lda Squ2_SfxLenCounter ;check for time to play second tone yet
cmp #$30 ;timer tick sound also executes this, not sure why
bne N2Tone
lda #$54 ;if so, load the tone directly into the reg
sta SND_SQUARE2_REG+2
N2Tone: bne DecrementSfx2Length
PlayBlast:
lda #$20 ;load length of fireworks/gunfire sound
sta Squ2_SfxLenCounter
ldy #$94 ;load reg contents of fireworks/gunfire sound
lda #$5e
bne SBlasJ
ContinueBlast:
lda Squ2_SfxLenCounter ;check for time to play second part
cmp #$18
bne DecrementSfx2Length
ldy #$93 ;load second part reg contents then
lda #$18
SBlasJ: bne BlstSJp ;unconditional branch to load rest of reg contents
PlayPowerUpGrab:
lda #$36 ;load length of power-up grab sound
sta Squ2_SfxLenCounter
ContinuePowerUpGrab:
lda Squ2_SfxLenCounter ;load frequency reg based on length left over
lsr ;divide by 2
bcs DecrementSfx2Length ;alter frequency every other frame
tay
lda PowerUpGrabFreqData-1,y ;use length left over / 2 for frequency offset
ldx #$5d ;store reg contents of power-up grab sound
ldy #$7f
LoadSqu2Regs:
jsr PlaySqu2Sfx
DecrementSfx2Length:
dec Squ2_SfxLenCounter ;decrement length of sfx
bne ExSfx2
EmptySfx2Buffer:
ldx #$00 ;initialize square 2's sound effects buffer
stx Square2SoundBuffer
StopSquare2Sfx:
ldx #$0d ;stop playing the sfx
stx SND_MASTERCTRL_REG
ldx #$0f
stx SND_MASTERCTRL_REG
ExSfx2: rts
Square2SfxHandler:
lda Square2SoundBuffer ;special handling for the 1-up sound to keep it
and #Sfx_ExtraLife ;from being interrupted by other sounds on square 2
bne ContinueExtraLife
ldy Square2SoundQueue ;check for sfx in queue
beq CheckSfx2Buffer
sty Square2SoundBuffer ;if found, put in buffer and check for the following
bmi PlayBowserFall ;bowser fall
lsr Square2SoundQueue
bcs PlayCoinGrab ;coin grab
lsr Square2SoundQueue
bcs PlayGrowPowerUp ;power-up reveal
lsr Square2SoundQueue
bcs PlayGrowVine ;vine grow
lsr Square2SoundQueue
bcs PlayBlast ;fireworks/gunfire
lsr Square2SoundQueue
bcs PlayTimerTick ;timer tick
lsr Square2SoundQueue
bcs PlayPowerUpGrab ;power-up grab
lsr Square2SoundQueue
bcs PlayExtraLife ;1-up
CheckSfx2Buffer:
lda Square2SoundBuffer ;check for sfx in buffer
beq ExS2H ;if not found, exit sub
bmi ContinueBowserFall ;bowser fall
lsr
bcs Cont_CGrab_TTick ;coin grab
lsr
bcs ContinueGrowItems ;power-up reveal
lsr
bcs ContinueGrowItems ;vine grow
lsr
bcs ContinueBlast ;fireworks/gunfire
lsr
bcs Cont_CGrab_TTick ;timer tick
lsr
bcs ContinuePowerUpGrab ;power-up grab
lsr
bcs ContinueExtraLife ;1-up
ExS2H: rts
Cont_CGrab_TTick:
jmp ContinueCGrabTTick
JumpToDecLength2:
jmp DecrementSfx2Length
PlayBowserFall:
lda #$38 ;load length of bowser defeat sound
sta Squ2_SfxLenCounter
ldy #$c4 ;load contents of reg for bowser defeat sound
lda #$18
BlstSJp: bne PBFRegs
ContinueBowserFall:
lda Squ2_SfxLenCounter ;check for almost near the end
cmp #$08
bne DecrementSfx2Length
ldy #$a4 ;if so, load the rest of reg contents for bowser defeat sound
lda #$5a
PBFRegs: ldx #$9f ;the fireworks/gunfire sound shares part of reg contents here
EL_LRegs: bne LoadSqu2Regs ;this is an unconditional branch outta here
PlayExtraLife:
lda #$30 ;load length of 1-up sound
sta Squ2_SfxLenCounter
ContinueExtraLife:
lda Squ2_SfxLenCounter
ldx #$03 ;load new tones only every eight frames
DivLLoop: lsr
bcs JumpToDecLength2 ;if any bits set here, branch to dec the length
dex
bne DivLLoop ;do this until all bits checked, if none set, continue
tay
lda ExtraLifeFreqData-1,y ;load our reg contents
ldx #$82
ldy #$7f
bne EL_LRegs ;unconditional branch
PlayGrowPowerUp:
lda #$10 ;load length of power-up reveal sound
bne GrowItemRegs
PlayGrowVine:
lda #$20 ;load length of vine grow sound
GrowItemRegs:
sta Squ2_SfxLenCounter
lda #$7f ;load contents of reg for both sounds directly
sta SND_SQUARE2_REG+1
lda #$00 ;start secondary counter for both sounds
sta Sfx_SecondaryCounter
ContinueGrowItems:
inc Sfx_SecondaryCounter ;increment secondary counter for both sounds
lda Sfx_SecondaryCounter ;this sound doesn't decrement the usual counter
lsr ;divide by 2 to get the offset
tay
cpy Squ2_SfxLenCounter ;have we reached the end yet?
beq StopGrowItems ;if so, branch to jump, and stop playing sounds
lda #$9d ;load contents of other reg directly
sta SND_SQUARE2_REG
lda PUp_VGrow_FreqData,y ;use secondary counter / 2 as offset for frequency regs
jsr SetFreq_Squ2
rts
StopGrowItems:
jmp EmptySfx2Buffer ;branch to stop playing sounds
;--------------------------------
BrickShatterFreqData:
.db $01, $0e, $0e, $0d, $0b, $06, $0c, $0f
.db $0a, $09, $03, $0d, $08, $0d, $06, $0c
PlayBrickShatter:
lda #$20 ;load length of brick shatter sound
sta Noise_SfxLenCounter
ContinueBrickShatter:
lda Noise_SfxLenCounter
lsr ;divide by 2 and check for bit set to use offset
bcc DecrementSfx3Length
tay
ldx BrickShatterFreqData,y ;load reg contents of brick shatter sound
lda BrickShatterEnvData,y
PlayNoiseSfx:
sta SND_NOISE_REG ;play the sfx
stx SND_NOISE_REG+2
lda #$18
sta SND_NOISE_REG+3
DecrementSfx3Length:
dec Noise_SfxLenCounter ;decrement length of sfx
bne ExSfx3
lda #$f0 ;if done, stop playing the sfx
sta SND_NOISE_REG
lda #$00
sta NoiseSoundBuffer
ExSfx3: rts
NoiseSfxHandler:
ldy NoiseSoundQueue ;check for sfx in queue
beq CheckNoiseBuffer
sty NoiseSoundBuffer ;if found, put in buffer
lsr NoiseSoundQueue
bcs PlayBrickShatter ;brick shatter
lsr NoiseSoundQueue
bcs PlayBowserFlame ;bowser flame
CheckNoiseBuffer:
lda NoiseSoundBuffer ;check for sfx in buffer
beq ExNH ;if not found, exit sub
lsr
bcs ContinueBrickShatter ;brick shatter
lsr
bcs ContinueBowserFlame ;bowser flame
ExNH: rts
PlayBowserFlame:
lda #$40 ;load length of bowser flame sound
sta Noise_SfxLenCounter
ContinueBowserFlame:
lda Noise_SfxLenCounter
lsr
tay
ldx #$0f ;load reg contents of bowser flame sound
lda BowserFlameEnvData-1,y
bne PlayNoiseSfx ;unconditional branch here
;--------------------------------
ContinueMusic:
jmp HandleSquare2Music ;if we have music, start with square 2 channel
MusicHandler:
lda EventMusicQueue ;check event music queue
bne LoadEventMusic
lda AreaMusicQueue ;check area music queue
bne LoadAreaMusic
lda EventMusicBuffer ;check both buffers
ora AreaMusicBuffer
bne ContinueMusic
rts ;no music, then leave
LoadEventMusic:
sta EventMusicBuffer ;copy event music queue contents to buffer
cmp #DeathMusic ;is it death music?
bne NoStopSfx ;if not, jump elsewhere
jsr StopSquare1Sfx ;stop sfx in square 1 and 2
jsr StopSquare2Sfx ;but clear only square 1's sfx buffer
NoStopSfx: ldx AreaMusicBuffer
stx AreaMusicBuffer_Alt ;save current area music buffer to be re-obtained later
ldy #$00
sty NoteLengthTblAdder ;default value for additional length byte offset
sty AreaMusicBuffer ;clear area music buffer
cmp #TimeRunningOutMusic ;is it time running out music?
bne FindEventMusicHeader
ldx #$08 ;load offset to be added to length byte of header
stx NoteLengthTblAdder
bne FindEventMusicHeader ;unconditional branch
LoadAreaMusic:
cmp #$04 ;is it underground music?
bne NoStop1 ;no, do not stop square 1 sfx
jsr StopSquare1Sfx
NoStop1: ldy #$10 ;start counter used only by ground level music
GMLoopB: sty GroundMusicHeaderOfs
HandleAreaMusicLoopB:
ldy #$00 ;clear event music buffer
sty EventMusicBuffer
sta AreaMusicBuffer ;copy area music queue contents to buffer
cmp #$01 ;is it ground level music?
bne FindAreaMusicHeader
inc GroundMusicHeaderOfs ;increment but only if playing ground level music
ldy GroundMusicHeaderOfs ;is it time to loopback ground level music?
cpy #$32
bne LoadHeader ;branch ahead with alternate offset
ldy #$11
bne GMLoopB ;unconditional branch
FindAreaMusicHeader:
ldy #$08 ;load Y for offset of area music
sty MusicOffset_Square2 ;residual instruction here
FindEventMusicHeader:
iny ;increment Y pointer based on previously loaded queue contents
lsr ;bit shift and increment until we find a set bit for music
bcc FindEventMusicHeader
LoadHeader:
lda MusicHeaderOffsetData,y ;load offset for header
tay
lda MusicHeaderData,y ;now load the header
sta NoteLenLookupTblOfs
lda MusicHeaderData+1,y
sta MusicDataLow
lda MusicHeaderData+2,y
sta MusicDataHigh
lda MusicHeaderData+3,y
sta MusicOffset_Triangle
lda MusicHeaderData+4,y
sta MusicOffset_Square1
lda MusicHeaderData+5,y
sta MusicOffset_Noise
sta NoiseDataLoopbackOfs
lda #$01 ;initialize music note counters
sta Squ2_NoteLenCounter
sta Squ1_NoteLenCounter
sta Tri_NoteLenCounter
sta Noise_BeatLenCounter
lda #$00 ;initialize music data offset for square 2
sta MusicOffset_Square2
sta AltRegContentFlag ;initialize alternate control reg data used by square 1
lda #$0b ;disable triangle channel and reenable it
sta SND_MASTERCTRL_REG
lda #$0f
sta SND_MASTERCTRL_REG
HandleSquare2Music:
dec Squ2_NoteLenCounter ;decrement square 2 note length
bne MiscSqu2MusicTasks ;is it time for more data? if not, branch to end tasks
ldy MusicOffset_Square2 ;increment square 2 music offset and fetch data
inc MusicOffset_Square2
lda (MusicData),y
beq EndOfMusicData ;if zero, the data is a null terminator
bpl Squ2NoteHandler ;if non-negative, data is a note
bne Squ2LengthHandler ;otherwise it is length data
EndOfMusicData:
lda EventMusicBuffer ;check secondary buffer for time running out music
cmp #TimeRunningOutMusic
bne NotTRO
lda AreaMusicBuffer_Alt ;load previously saved contents of primary buffer
bne MusicLoopBack ;and start playing the song again if there is one
NotTRO: and #VictoryMusic ;check for victory music (the only secondary that loops)
bne VictoryMLoopBack
lda AreaMusicBuffer ;check primary buffer for any music except pipe intro
and #%01011111
bne MusicLoopBack ;if any area music except pipe intro, music loops
lda #$00 ;clear primary and secondary buffers and initialize
sta AreaMusicBuffer ;control regs of square and triangle channels
sta EventMusicBuffer
sta SND_TRIANGLE_REG
lda #$90
sta SND_SQUARE1_REG
sta SND_SQUARE2_REG
rts
MusicLoopBack:
jmp HandleAreaMusicLoopB
VictoryMLoopBack:
jmp LoadEventMusic
Squ2LengthHandler:
jsr ProcessLengthData ;store length of note
sta Squ2_NoteLenBuffer
ldy MusicOffset_Square2 ;fetch another byte (MUST NOT BE LENGTH BYTE!)
inc MusicOffset_Square2
lda (MusicData),y
Squ2NoteHandler:
ldx Square2SoundBuffer ;is there a sound playing on this channel?
bne SkipFqL1
jsr SetFreq_Squ2 ;no, then play the note
beq Rest ;check to see if note is rest
jsr LoadControlRegs ;if not, load control regs for square 2
Rest: sta Squ2_EnvelopeDataCtrl ;save contents of A
jsr Dump_Sq2_Regs ;dump X and Y into square 2 control regs
SkipFqL1: lda Squ2_NoteLenBuffer ;save length in square 2 note counter
sta Squ2_NoteLenCounter
MiscSqu2MusicTasks:
lda Square2SoundBuffer ;is there a sound playing on square 2?
bne HandleSquare1Music
lda EventMusicBuffer ;check for death music or d4 set on secondary buffer
and #%10010001 ;note that regs for death music or d4 are loaded by default
bne HandleSquare1Music
ldy Squ2_EnvelopeDataCtrl ;check for contents saved from LoadControlRegs
beq NoDecEnv1
dec Squ2_EnvelopeDataCtrl ;decrement unless already zero
NoDecEnv1: jsr LoadEnvelopeData ;do a load of envelope data to replace default
sta SND_SQUARE2_REG ;based on offset set by first load unless playing
ldx #$7f ;death music or d4 set on secondary buffer
stx SND_SQUARE2_REG+1
HandleSquare1Music:
ldy MusicOffset_Square1 ;is there a nonzero offset here?
beq HandleTriangleMusic ;if not, skip ahead to the triangle channel
dec Squ1_NoteLenCounter ;decrement square 1 note length
bne MiscSqu1MusicTasks ;is it time for more data?
FetchSqu1MusicData:
ldy MusicOffset_Square1 ;increment square 1 music offset and fetch data
inc MusicOffset_Square1
lda (MusicData),y
bne Squ1NoteHandler ;if nonzero, then skip this part
lda #$83
sta SND_SQUARE1_REG ;store some data into control regs for square 1
lda #$94 ;and fetch another byte of data, used to give
sta SND_SQUARE1_REG+1 ;death music its unique sound
sta AltRegContentFlag
bne FetchSqu1MusicData ;unconditional branch
Squ1NoteHandler:
jsr AlternateLengthHandler
sta Squ1_NoteLenCounter ;save contents of A in square 1 note counter
ldy Square1SoundBuffer ;is there a sound playing on square 1?
bne HandleTriangleMusic
txa
and #%00111110 ;change saved data to appropriate note format
jsr SetFreq_Squ1 ;play the note
beq SkipCtrlL
jsr LoadControlRegs
SkipCtrlL: sta Squ1_EnvelopeDataCtrl ;save envelope offset
jsr Dump_Squ1_Regs
MiscSqu1MusicTasks:
lda Square1SoundBuffer ;is there a sound playing on square 1?
bne HandleTriangleMusic
lda EventMusicBuffer ;check for death music or d4 set on secondary buffer
and #%10010001
bne DeathMAltReg
ldy Squ1_EnvelopeDataCtrl ;check saved envelope offset
beq NoDecEnv2
dec Squ1_EnvelopeDataCtrl ;decrement unless already zero
NoDecEnv2: jsr LoadEnvelopeData ;do a load of envelope data
sta SND_SQUARE1_REG ;based on offset set by first load
DeathMAltReg: lda AltRegContentFlag ;check for alternate control reg data
bne DoAltLoad
lda #$7f ;load this value if zero, the alternate value
DoAltLoad: sta SND_SQUARE1_REG+1 ;if nonzero, and let's move on
HandleTriangleMusic:
lda MusicOffset_Triangle
dec Tri_NoteLenCounter ;decrement triangle note length
bne HandleNoiseMusic ;is it time for more data?
ldy MusicOffset_Triangle ;increment square 1 music offset and fetch data
inc MusicOffset_Triangle
lda (MusicData),y
beq LoadTriCtrlReg ;if zero, skip all this and move on to noise
bpl TriNoteHandler ;if non-negative, data is note
jsr ProcessLengthData ;otherwise, it is length data
sta Tri_NoteLenBuffer ;save contents of A
lda #$1f
sta SND_TRIANGLE_REG ;load some default data for triangle control reg
ldy MusicOffset_Triangle ;fetch another byte
inc MusicOffset_Triangle
lda (MusicData),y
beq LoadTriCtrlReg ;check once more for nonzero data
TriNoteHandler:
jsr SetFreq_Tri
ldx Tri_NoteLenBuffer ;save length in triangle note counter
stx Tri_NoteLenCounter
lda EventMusicBuffer
and #%01101110 ;check for death music or d4 set on secondary buffer
bne NotDOrD4 ;if playing any other secondary, skip primary buffer check
lda AreaMusicBuffer ;check primary buffer for water or castle level music
and #%00001010
beq HandleNoiseMusic ;if playing any other primary, or death or d4, go on to noise routine
NotDOrD4: txa ;if playing water or castle music or any secondary
cmp #$12 ;besides death music or d4 set, check length of note
bcs LongN
lda EventMusicBuffer ;check for win castle music again if not playing a long note
and #EndOfCastleMusic
beq MediN
lda #$0f ;load value $0f if playing the win castle music and playing a short
bne LoadTriCtrlReg ;note, load value $1f if playing water or castle level music or any
MediN: lda #$1f ;secondary besides death and d4 except win castle or win castle and playing
bne LoadTriCtrlReg ;a short note, and load value $ff if playing a long note on water, castle
LongN: lda #$ff ;or any secondary (including win castle) except death and d4
LoadTriCtrlReg:
sta SND_TRIANGLE_REG ;save final contents of A into control reg for triangle
HandleNoiseMusic:
lda AreaMusicBuffer ;check if playing underground or castle music
and #%11110011
beq ExitMusicHandler ;if so, skip the noise routine
dec Noise_BeatLenCounter ;decrement noise beat length
bne ExitMusicHandler ;is it time for more data?
FetchNoiseBeatData:
ldy MusicOffset_Noise ;increment noise beat offset and fetch data
inc MusicOffset_Noise
lda (MusicData),y ;get noise beat data, if nonzero, branch to handle
bne NoiseBeatHandler
lda NoiseDataLoopbackOfs ;if data is zero, reload original noise beat offset
sta MusicOffset_Noise ;and loopback next time around
bne FetchNoiseBeatData ;unconditional branch
NoiseBeatHandler:
jsr AlternateLengthHandler
sta Noise_BeatLenCounter ;store length in noise beat counter
txa
and #%00111110 ;reload data and erase length bits
beq SilentBeat ;if no beat data, silence
cmp #$30 ;check the beat data and play the appropriate
beq LongBeat ;noise accordingly
cmp #$20
beq StrongBeat
and #%00010000
beq SilentBeat
lda #$1c ;short beat data
ldx #$03
ldy #$18
bne PlayBeat
StrongBeat:
lda #$1c ;strong beat data
ldx #$0c
ldy #$18
bne PlayBeat
LongBeat:
lda #$1c ;long beat data
ldx #$03
ldy #$58
bne PlayBeat
SilentBeat:
lda #$10 ;silence
PlayBeat:
sta SND_NOISE_REG ;load beat data into noise regs
stx SND_NOISE_REG+2
sty SND_NOISE_REG+3
ExitMusicHandler:
rts
AlternateLengthHandler:
tax ;save a copy of original byte into X
ror ;save LSB from original byte into carry
txa ;reload original byte and rotate three times
rol ;turning xx00000x into 00000xxx, with the
rol ;bit in carry as the MSB here
rol
ProcessLengthData:
and #%00000111 ;clear all but the three LSBs
clc
adc $f0 ;add offset loaded from first header byte
adc NoteLengthTblAdder ;add extra if time running out music
tay
lda MusicLengthLookupTbl,y ;load length
rts
LoadControlRegs:
lda EventMusicBuffer ;check secondary buffer for win castle music
and #EndOfCastleMusic
beq NotECstlM
lda #$04 ;this value is only used for win castle music
bne AllMus ;unconditional branch
NotECstlM: lda AreaMusicBuffer
and #%01111101 ;check primary buffer for water music
beq WaterMus
lda #$08 ;this is the default value for all other music
bne AllMus
WaterMus: lda #$28 ;this value is used for water music and all other event music
AllMus: ldx #$82 ;load contents of other sound regs for square 2
ldy #$7f
rts
LoadEnvelopeData:
lda EventMusicBuffer ;check secondary buffer for win castle music
and #EndOfCastleMusic
beq LoadUsualEnvData
lda EndOfCastleMusicEnvData,y ;load data from offset for win castle music
rts
LoadUsualEnvData:
lda AreaMusicBuffer ;check primary buffer for water music
and #%01111101
beq LoadWaterEventMusEnvData
lda AreaMusicEnvData,y ;load default data from offset for all other music
rts
LoadWaterEventMusEnvData:
lda WaterEventMusEnvData,y ;load data from offset for water music and all other event music
rts
;--------------------------------
;music header offsets
MusicHeaderData:
.db DeathMusHdr-MHD ;event music
.db GameOverMusHdr-MHD
.db VictoryMusHdr-MHD
.db WinCastleMusHdr-MHD
.db GameOverMusHdr-MHD
.db EndOfLevelMusHdr-MHD
.db TimeRunningOutHdr-MHD
.db SilenceHdr-MHD
.db GroundLevelPart1Hdr-MHD ;area music
.db WaterMusHdr-MHD
.db UndergroundMusHdr-MHD
.db CastleMusHdr-MHD
.db Star_CloudHdr-MHD
.db GroundLevelLeadInHdr-MHD
.db Star_CloudHdr-MHD
.db SilenceHdr-MHD
.db GroundLevelLeadInHdr-MHD ;ground level music layout
.db GroundLevelPart1Hdr-MHD, GroundLevelPart1Hdr-MHD
.db GroundLevelPart2AHdr-MHD, GroundLevelPart2BHdr-MHD, GroundLevelPart2AHdr-MHD, GroundLevelPart2CHdr-MHD
.db GroundLevelPart2AHdr-MHD, GroundLevelPart2BHdr-MHD, GroundLevelPart2AHdr-MHD, GroundLevelPart2CHdr-MHD
.db GroundLevelPart3AHdr-MHD, GroundLevelPart3BHdr-MHD, GroundLevelPart3AHdr-MHD, GroundLevelLeadInHdr-MHD
.db GroundLevelPart1Hdr-MHD, GroundLevelPart1Hdr-MHD
.db GroundLevelPart4AHdr-MHD, GroundLevelPart4BHdr-MHD, GroundLevelPart4AHdr-MHD, GroundLevelPart4CHdr-MHD
.db GroundLevelPart4AHdr-MHD, GroundLevelPart4BHdr-MHD, GroundLevelPart4AHdr-MHD, GroundLevelPart4CHdr-MHD
.db GroundLevelPart3AHdr-MHD, GroundLevelPart3BHdr-MHD, GroundLevelPart3AHdr-MHD, GroundLevelLeadInHdr-MHD
.db GroundLevelPart4AHdr-MHD, GroundLevelPart4BHdr-MHD, GroundLevelPart4AHdr-MHD, GroundLevelPart4CHdr-MHD
;music headers
;header format is as follows:
;1 byte - length byte offset
;2 bytes - music data address
;1 byte - triangle data offset
;1 byte - square 1 data offset
;1 byte - noise data offset (not used by secondary music)
TimeRunningOutHdr: .db $08, <TimeRunOutMusData, >TimeRunOutMusData, $27, $18
Star_CloudHdr: .db $20, <Star_CloudMData, >Star_CloudMData, $2e, $1a, $40
EndOfLevelMusHdr: .db $20, <WinLevelMusData, >WinLevelMusData, $3d, $21
ResidualHeaderData: .db $20, $c4, $fc, $3f, $1d
UndergroundMusHdr: .db $18, <UndergroundMusData, >UndergroundMusData, $00, $00
SilenceHdr: .db $08, <SilenceData, >SilenceData, $00
CastleMusHdr: .db $00, <CastleMusData, >CastleMusData, $93, $62
VictoryMusHdr: .db $10, <VictoryMusData, >VictoryMusData, $24, $14
GameOverMusHdr: .db $18, <GameOverMusData, >GameOverMusData, $1e, $14
WaterMusHdr: .db $08, <WaterMusData, >WaterMusData, $a0, $70, $68
WinCastleMusHdr: .db $08, <EndOfCastleMusData, >EndOfCastleMusData, $4c, $24
GroundLevelPart1Hdr: .db $18, <GroundM_P1Data, >GroundM_P1Data, $2d, $1c, $b8
GroundLevelPart2AHdr: .db $18, <GroundM_P2AData, >GroundM_P2AData, $20, $12, $70
GroundLevelPart2BHdr: .db $18, <GroundM_P2BData, >GroundM_P2BData, $1b, $10, $44
GroundLevelPart2CHdr: .db $18, <GroundM_P2CData, >GroundM_P2CData, $11, $0a, $1c
GroundLevelPart3AHdr: .db $18, <GroundM_P3AData, >GroundM_P3AData, $2d, $10, $58
GroundLevelPart3BHdr: .db $18, <GroundM_P3BData, >GroundM_P3BData, $14, $0d, $3f
GroundLevelLeadInHdr: .db $18, <GroundMLdInData, >GroundMLdInData, $15, $0d, $21
GroundLevelPart4AHdr: .db $18, <GroundM_P4AData, >GroundM_P4AData, $18, $10, $7a
GroundLevelPart4BHdr: .db $18, <GroundM_P4BData, >GroundM_P4BData, $19, $0f, $54
GroundLevelPart4CHdr: .db $18, <GroundM_P4CData, >GroundM_P4CData, $1e, $12, $2b
DeathMusHdr: .db $18, <DeathMusData, >DeathMusData, $1e, $0f, $2d
;--------------------------------
;MUSIC DATA
;square 2/triangle format
;d7 - length byte flag (0-note, 1-length)
;if d7 is set to 0 and d6-d0 is nonzero:
;d6-d0 - note offset in frequency look-up table (must be even)
;if d7 is set to 1:
;d6-d3 - unused
;d2-d0 - length offset in length look-up table
;value of $00 in square 2 data is used as null terminator, affects all sound channels
;value of $00 in triangle data causes routine to skip note
;square 1 format
;d7-d6, d0 - length offset in length look-up table (bit order is d0,d7,d6)
;d5-d1 - note offset in frequency look-up table
;value of $00 in square 1 data is flag alternate control reg data to be loaded
;noise format
;d7-d6, d0 - length offset in length look-up table (bit order is d0,d7,d6)
;d5-d4 - beat type (0 - rest, 1 - short, 2 - strong, 3 - long)
;d3-d1 - unused
;value of $00 in noise data is used as null terminator, affects only noise
;all music data is organized into sections (unless otherwise stated):
;square 2, square 1, triangle, noise
Star_CloudMData:
.db $84, $2c, $2c, $2c, $82, $04, $2c, $04, $85, $2c, $84, $2c, $2c
.db $2a, $2a, $2a, $82, $04, $2a, $04, $85, $2a, $84, $2a, $2a, $00
.db $1f, $1f, $1f, $98, $1f, $1f, $98, $9e, $98, $1f
.db $1d, $1d, $1d, $94, $1d, $1d, $94, $9c, $94, $1d
.db $86, $18, $85, $26, $30, $84, $04, $26, $30
.db $86, $14, $85, $22, $2c, $84, $04, $22, $2c
.db $21, $d0, $c4, $d0, $31, $d0, $c4, $d0, $00
GroundM_P1Data:
.db $85, $2c, $22, $1c, $84, $26, $2a, $82, $28, $26, $04
.db $87, $22, $34, $3a, $82, $40, $04, $36, $84, $3a, $34
.db $82, $2c, $30, $85, $2a
SilenceData:
.db $00
.db $5d, $55, $4d, $15, $19, $96, $15, $d5, $e3, $eb
.db $2d, $a6, $2b, $27, $9c, $9e, $59
.db $85, $22, $1c, $14, $84, $1e, $22, $82, $20, $1e, $04, $87
.db $1c, $2c, $34, $82, $36, $04, $30, $34, $04, $2c, $04, $26
.db $2a, $85, $22
GroundM_P2AData:
.db $84, $04, $82, $3a, $38, $36, $32, $04, $34
.db $04, $24, $26, $2c, $04, $26, $2c, $30, $00
.db $05, $b4, $b2, $b0, $2b, $ac, $84
.db $9c, $9e, $a2, $84, $94, $9c, $9e
.db $85, $14, $22, $84, $2c, $85, $1e
.db $82, $2c, $84, $2c, $1e
GroundM_P2BData:
.db $84, $04, $82, $3a, $38, $36, $32, $04, $34
.db $04, $64, $04, $64, $86, $64, $00
.db $05, $b4, $b2, $b0, $2b, $ac, $84
.db $37, $b6, $b6, $45
.db $85, $14, $1c, $82, $22, $84, $2c
.db $4e, $82, $4e, $84, $4e, $22
GroundM_P2CData:
.db $84, $04, $85, $32, $85, $30, $86, $2c, $04, $00
.db $05, $a4, $05, $9e, $05, $9d, $85
.db $84, $14, $85, $24, $28, $2c, $82
.db $22, $84, $22, $14
.db $21, $d0, $c4, $d0, $31, $d0, $c4, $d0, $00
GroundM_P3AData:
.db $82, $2c, $84, $2c, $2c, $82, $2c, $30
.db $04, $34, $2c, $04, $26, $86, $22, $00
.db $a4, $25, $25, $a4, $29, $a2, $1d, $9c, $95
GroundM_P3BData:
.db $82, $2c, $2c, $04, $2c, $04, $2c, $30, $85, $34, $04, $04, $00
.db $a4, $25, $25, $a4, $a8, $63, $04
;triangle data used by both sections of third part
.db $85, $0e, $1a, $84, $24, $85, $22, $14, $84, $0c
GroundMLdInData:
.db $82, $34, $84, $34, $34, $82, $2c, $84, $34, $86, $3a, $04, $00
.db $a0, $21, $21, $a0, $21, $2b, $05, $a3
.db $82, $18, $84, $18, $18, $82, $18, $18, $04, $86, $3a, $22
;noise data used by lead-in and third part sections
.db $31, $90, $31, $90, $31, $71, $31, $90, $90, $90, $00
GroundM_P4AData:
.db $82, $34, $84, $2c, $85, $22, $84, $24
.db $82, $26, $36, $04, $36, $86, $26, $00
.db $ac, $27, $5d, $1d, $9e, $2d, $ac, $9f
.db $85, $14, $82, $20, $84, $22, $2c
.db $1e, $1e, $82, $2c, $2c, $1e, $04
GroundM_P4BData:
.db $87, $2a, $40, $40, $40, $3a, $36
.db $82, $34, $2c, $04, $26, $86, $22, $00
.db $e3, $f7, $f7, $f7, $f5, $f1, $ac, $27, $9e, $9d
.db $85, $18, $82, $1e, $84, $22, $2a
.db $22, $22, $82, $2c, $2c, $22, $04
DeathMusData:
.db $86, $04 ;death music share data with fourth part c of ground level music
GroundM_P4CData:
.db $82, $2a, $36, $04, $36, $87, $36, $34, $30, $86, $2c, $04, $00
.db $00, $68, $6a, $6c, $45 ;death music only
.db $a2, $31, $b0, $f1, $ed, $eb, $a2, $1d, $9c, $95
.db $86, $04 ;death music only
.db $85, $22, $82, $22, $87, $22, $26, $2a, $84, $2c, $22, $86, $14
;noise data used by fourth part sections
.db $51, $90, $31, $11, $00
CastleMusData:
.db $80, $22, $28, $22, $26, $22, $24, $22, $26
.db $22, $28, $22, $2a, $22, $28, $22, $26
.db $22, $28, $22, $26, $22, $24, $22, $26
.db $22, $28, $22, $2a, $22, $28, $22, $26
.db $20, $26, $20, $24, $20, $26, $20, $28
.db $20, $26, $20, $28, $20, $26, $20, $24
.db $20, $26, $20, $24, $20, $26, $20, $28
.db $20, $26, $20, $28, $20, $26, $20, $24
.db $28, $30, $28, $32, $28, $30, $28, $2e
.db $28, $30, $28, $2e, $28, $2c, $28, $2e
.db $28, $30, $28, $32, $28, $30, $28, $2e
.db $28, $30, $28, $2e, $28, $2c, $28, $2e, $00
.db $04, $70, $6e, $6c, $6e, $70, $72, $70, $6e
.db $70, $6e, $6c, $6e, $70, $72, $70, $6e
.db $6e, $6c, $6e, $70, $6e, $70, $6e, $6c
.db $6e, $6c, $6e, $70, $6e, $70, $6e, $6c
.db $76, $78, $76, $74, $76, $74, $72, $74
.db $76, $78, $76, $74, $76, $74, $72, $74
.db $84, $1a, $83, $18, $20, $84, $1e, $83, $1c, $28
.db $26, $1c, $1a, $1c
GameOverMusData:
.db $82, $2c, $04, $04, $22, $04, $04, $84, $1c, $87
.db $26, $2a, $26, $84, $24, $28, $24, $80, $22, $00
.db $9c, $05, $94, $05, $0d, $9f, $1e, $9c, $98, $9d
.db $82, $22, $04, $04, $1c, $04, $04, $84, $14
.db $86, $1e, $80, $16, $80, $14
TimeRunOutMusData:
.db $81, $1c, $30, $04, $30, $30, $04, $1e, $32, $04, $32, $32
.db $04, $20, $34, $04, $34, $34, $04, $36, $04, $84, $36, $00
.db $46, $a4, $64, $a4, $48, $a6, $66, $a6, $4a, $a8, $68, $a8
.db $6a, $44, $2b
.db $81, $2a, $42, $04, $42, $42, $04, $2c, $64, $04, $64, $64
.db $04, $2e, $46, $04, $46, $46, $04, $22, $04, $84, $22
WinLevelMusData:
.db $87, $04, $06, $0c, $14, $1c, $22, $86, $2c, $22
.db $87, $04, $60, $0e, $14, $1a, $24, $86, $2c, $24
.db $87, $04, $08, $10, $18, $1e, $28, $86, $30, $30
.db $80, $64, $00
.db $cd, $d5, $dd, $e3, $ed, $f5, $bb, $b5, $cf, $d5
.db $db, $e5, $ed, $f3, $bd, $b3, $d1, $d9, $df, $e9
.db $f1, $f7, $bf, $ff, $ff, $ff, $34
.db $00 ;unused byte
.db $86, $04, $87, $14, $1c, $22, $86, $34, $84, $2c
.db $04, $04, $04, $87, $14, $1a, $24, $86, $32, $84
.db $2c, $04, $86, $04, $87, $18, $1e, $28, $86, $36
.db $87, $30, $30, $30, $80, $2c
;square 2 and triangle use the same data, square 1 is unused
UndergroundMusData:
.db $82, $14, $2c, $62, $26, $10, $28, $80, $04
.db $82, $14, $2c, $62, $26, $10, $28, $80, $04
.db $82, $08, $1e, $5e, $18, $60, $1a, $80, $04
.db $82, $08, $1e, $5e, $18, $60, $1a, $86, $04
.db $83, $1a, $18, $16, $84, $14, $1a, $18, $0e, $0c
.db $16, $83, $14, $20, $1e, $1c, $28, $26, $87
.db $24, $1a, $12, $10, $62, $0e, $80, $04, $04
.db $00
;noise data directly follows square 2 here unlike in other songs
WaterMusData:
.db $82, $18, $1c, $20, $22, $26, $28
.db $81, $2a, $2a, $2a, $04, $2a, $04, $83, $2a, $82, $22
.db $86, $34, $32, $34, $81, $04, $22, $26, $2a, $2c, $30
.db $86, $34, $83, $32, $82, $36, $84, $34, $85, $04, $81, $22
.db $86, $30, $2e, $30, $81, $04, $22, $26, $2a, $2c, $2e
.db $86, $30, $83, $22, $82, $36, $84, $34, $85, $04, $81, $22
.db $86, $3a, $3a, $3a, $82, $3a, $81, $40, $82, $04, $81, $3a
.db $86, $36, $36, $36, $82, $36, $81, $3a, $82, $04, $81, $36
.db $86, $34, $82, $26, $2a, $36
.db $81, $34, $34, $85, $34, $81, $2a, $86, $2c, $00
.db $84, $90, $b0, $84, $50, $50, $b0, $00
.db $98, $96, $94, $92, $94, $96, $58, $58, $58, $44
.db $5c, $44, $9f, $a3, $a1, $a3, $85, $a3, $e0, $a6
.db $23, $c4, $9f, $9d, $9f, $85, $9f, $d2, $a6, $23
.db $c4, $b5, $b1, $af, $85, $b1, $af, $ad, $85, $95
.db $9e, $a2, $aa, $6a, $6a, $6b, $5e, $9d
.db $84, $04, $04, $82, $22, $86, $22
.db $82, $14, $22, $2c, $12, $22, $2a, $14, $22, $2c
.db $1c, $22, $2c, $14, $22, $2c, $12, $22, $2a, $14
.db $22, $2c, $1c, $22, $2c, $18, $22, $2a, $16, $20
.db $28, $18, $22, $2a, $12, $22, $2a, $18, $22, $2a
.db $12, $22, $2a, $14, $22, $2c, $0c, $22, $2c, $14, $22, $34, $12
.db $22, $30, $10, $22, $2e, $16, $22, $34, $18, $26
.db $36, $16, $26, $36, $14, $26, $36, $12, $22, $36
.db $5c, $22, $34, $0c, $22, $22, $81, $1e, $1e, $85, $1e
.db $81, $12, $86, $14
EndOfCastleMusData:
.db $81, $2c, $22, $1c, $2c, $22, $1c, $85, $2c, $04
.db $81, $2e, $24, $1e, $2e, $24, $1e, $85, $2e, $04
.db $81, $32, $28, $22, $32, $28, $22, $85, $32
.db $87, $36, $36, $36, $84, $3a, $00
.db $5c, $54, $4c, $5c, $54, $4c
.db $5c, $1c, $1c, $5c, $5c, $5c, $5c
.db $5e, $56, $4e, $5e, $56, $4e
.db $5e, $1e, $1e, $5e, $5e, $5e, $5e
.db $62, $5a, $50, $62, $5a, $50
.db $62, $22, $22, $62, $e7, $e7, $e7, $2b
.db $86, $14, $81, $14, $80, $14, $14, $81, $14, $14, $14, $14
.db $86, $16, $81, $16, $80, $16, $16, $81, $16, $16, $16, $16
.db $81, $28, $22, $1a, $28, $22, $1a, $28, $80, $28, $28
.db $81, $28, $87, $2c, $2c, $2c, $84, $30
VictoryMusData:
.db $83, $04, $84, $0c, $83, $62, $10, $84, $12
.db $83, $1c, $22, $1e, $22, $26, $18, $1e, $04, $1c, $00
.db $e3, $e1, $e3, $1d, $de, $e0, $23
.db $ec, $75, $74, $f0, $f4, $f6, $ea, $31, $2d
.db $83, $12, $14, $04, $18, $1a, $1c, $14
.db $26, $22, $1e, $1c, $18, $1e, $22, $0c, $14
;unused space
.db $ff, $ff, $ff
FreqRegLookupTbl:
.db $00, $88, $00, $2f, $00, $00
.db $02, $a6, $02, $80, $02, $5c, $02, $3a
.db $02, $1a, $01, $df, $01, $c4, $01, $ab
.db $01, $93, $01, $7c, $01, $67, $01, $53
.db $01, $40, $01, $2e, $01, $1d, $01, $0d
.db $00, $fe, $00, $ef, $00, $e2, $00, $d5
.db $00, $c9, $00, $be, $00, $b3, $00, $a9
.db $00, $a0, $00, $97, $00, $8e, $00, $86
.db $00, $77, $00, $7e, $00, $71, $00, $54
.db $00, $64, $00, $5f, $00, $59, $00, $50
.db $00, $47, $00, $43, $00, $3b, $00, $35
.db $00, $2a, $00, $23, $04, $75, $03, $57
.db $02, $f9, $02, $cf, $01, $fc, $00, $6a
MusicLengthLookupTbl:
.db $05, $0a, $14, $28, $50, $1e, $3c, $02
.db $04, $08, $10, $20, $40, $18, $30, $0c
.db $03, $06, $0c, $18, $30, $12, $24, $08
.db $36, $03, $09, $06, $12, $1b, $24, $0c
.db $24, $02, $06, $04, $0c, $12, $18, $08
.db $12, $01, $03, $02, $06, $09, $0c, $04
EndOfCastleMusicEnvData:
.db $98, $99, $9a, $9b
AreaMusicEnvData:
.db $90, $94, $94, $95, $95, $96, $97, $98
WaterEventMusEnvData:
.db $90, $91, $92, $92, $93, $93, $93, $94
.db $94, $94, $94, $94, $94, $95, $95, $95
.db $95, $95, $95, $96, $96, $96, $96, $96
.db $96, $96, $96, $96, $96, $96, $96, $96
.db $96, $96, $96, $96, $95, $95, $94, $93
BowserFlameEnvData:
.db $15, $16, $16, $17, $17, $18, $19, $19
.db $1a, $1a, $1c, $1d, $1d, $1e, $1e, $1f
.db $1f, $1f, $1f, $1e, $1d, $1c, $1e, $1f
.db $1f, $1e, $1d, $1c, $1a, $18, $16, $14
BrickShatterEnvData:
.db $15, $16, $16, $17, $17, $18, $19, $19
.db $1a, $1a, $1c, $1d, $1d, $1e, $1e, $1f
;-------------------------------------------------------------------------------------
;INTERRUPT VECTORS
.dw NonMaskableInterrupt
.dw Start
.dw $fff0 ;unused
@LiterallyLegendary
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LiterallyLegendary commented Oct 2, 2020

do you know where to find a complete hexadecimal view of Super Mario Bros ROM with added description?

@jakiki6
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jakiki6 commented Oct 2, 2020

You can build the rom with my build system for it.

https://github.com/jakiki6/smb1-disasm/

@LiterallyLegendary
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LiterallyLegendary commented Oct 11, 2020

How do I interpret the level data? Somebody needs to make a table with two columns: one with all of the possible hexadecimal bytes of level data, the other column with all of the level objects those bytes represent.

@masterawr
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Is someone going to make a PC/Linux port of this?

@jakiki6
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jakiki6 commented Nov 3, 2020

This is going to be hard since the code is written in 6592 assembly and uses features to render the game that would have to emulate. You better go with an emulator.

@BdR76
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BdR76 commented Nov 3, 2020

How do I interpret the level data?

The levels are constructed using a limited set of block combinations. Every time the game scrolls to the right it decodes a vertical slice of the level (I think that's also why you can't scroll to the left).

So each byte of the level data at ;AREA OBJECT DATA consists of two nybbles (4 bits). Each nybble value (0..f) corresponds with one of the 16 floor/ceiling possibilities at TerrainRenderBits. Depending on the level theme, the floor(s) and ceiling blocks are rendered, which happens at RenderSceneryTerrain.

So it's a bit complicated and restricting, certain block layouts are not possible and there's a fixed scrolling direction, but the advantage is that it's really efficient in memory usage.

@Xzerixan
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Xzerixan commented Dec 1, 2020

Does each tile have it's own code?
Cuz that's what I understood from this screenshot
image

@LiterallyLegendary
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Does each tile have it's own code?
Cuz that's what I understood from this screenshot
image

Yes, that's right. I just wish I knew what tiles every tile corresponds to.

@LiterallyLegendary
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At what memory addresses are all the textures for all the tiles stored?

@rootstop
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That's exactly what i find, thanks for share, will update my website after all done.

@NoveltyMan
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Is it possible to port the code on a different console, like the Master System?

@BdR76
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BdR76 commented Jul 13, 2021

Is it possible to port the code on a different console, like the Master System?

You can't just copy&paste the source into a Master System compiler, and it's not a matter of just search&replace some instructions and then it runs.

There was a Commodore 64 port of SMB, I'm not 100% sure but I think it was based on this source code. The C64 has the exact same CPU as the NES which would make it (slightly) easier, but even then it needs a lot of adjustments. For the Master System it's even more work because you'd have to "translate" each CPU instruction, and make changes for the different video memory etc. So technically you can use this source to port the game, but it depends on how much time you want to spend on it.

@NoveltyMan
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Is it possible to port the code on a different console, like the Master System?

You can't just copy&paste the source into a Master System compiler, and it's not a matter of just search&replace some instructions and then it runs.

There was a Commodore 64 port of SMB, I'm not 100% sure but I think it was based on this source code. The C64 has the exact same CPU as the NES which would make it (slightly) easier, but even then it needs a lot of adjustments. For the Master System it's even more work because you'd have to "translate" each CPU instruction, and make changes for the different video memory etc. So technically you can use this source to port the game, but it depends on how much time you want to spend on it.

There exists a unfinished Sega Master System port of MegaMan 2.
It's based on a decompiled source code.
https://www.smspower.org/Homebrew/MegaMan2-SMS

@subarumike
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Building this out in either unreal or unity would be at most 2 days work. Then you can port it to whatever you want.

@bhupesh05
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Holy Jesus Lord...

yes we live in crazy world how he made it

@ErnestoBorio
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Is this supposed to be the ROM without sprite data???

Yes, the graphics in SMB and most NES games were stored in a separate ROM chip (Called CHR-ROM).
This is a dump of the Program logic and data, which is stored in another chip, the PRG-ROM.

@yashika
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yashika commented Sep 12, 2022

原来这样

@FrenzyExists
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Homie's coding in the language of the Gods

@plpep69
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plpep69 commented Nov 18, 2022

damn how i compile this shit

@ErnestoBorio
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damn how i compile this shit

See line 17.

@plpep69
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plpep69 commented Nov 19, 2022

damn how i compile this shit

See line 17.

no te entendi ni una mierda jaja salu2

@Mohammed-Nasif
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Really nice to see this

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ghost commented May 5, 2023

i played super mario bros yesterday and when i was a child

@plpep69
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plpep69 commented Jun 29, 2023

so rertro!!11

@Wojtek9388
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how do i make a sprite move around using left arrow and right arrow i have a script to read the controller but i dont know where to go from there

@leogit23
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leogit23 commented Dec 7, 2023

Wow, how many peoples to do this class? Woooooow

@maitrungduc1410
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Amazing!

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