Balloons version 2 - PC-G815 - z88dk C language https://poke-com.jimdofree.com/z88dk-%E3%81%A7%E3%82%AF%E3%83%AD%E3%82%B9%E9%96%8B%E7%99%BA%E3%81%99%E3%82%8B/

balloon2.c

/*
  Balloons version 2 | PC-G815 | z88dk C language
  Copyright (c) 2025 BALLOON | FU-SEN
  The MIT License (MIT) - https://mit.balloon.net.eu.org/#2025

  There is a problem with the operation with emulator g800!
  (version 0.11.4 and 20240414 (beta))
  zcc +g800 -create-app -bn balloon2 balloon2.c
  --> MON
      R
      G100
*/

void putchr(char posx, char posy, char pchr)
{
#asm
    ld   ix,0
    add  ix,sp
    ld   a,(ix+2)       ; pchr
    ld   d,(ix+4)       ; posy
    ld   e,(ix+6)       ; posx
    call 0be62h
#endasm
}

void putimg(char posx, char posy, int addr, char size)
{
#asm
    ld   ix,0
    add  ix,sp
    ld   b,(ix+2)       ; size
    ld   l,(ix+4)       ; addr
    ld   h,(ix+5)
    ld   d,(ix+6)       ; posy
    ld   e,(ix+8)       ; posx
    call 0bfd0h
#endasm
}

void getcodei()
{
#asm
    call 0be53h
    ld   l,a
    ld   h,0
#endasm
}

int peek(int addr)
{
#asm
    ld   a,(hl)         ; addr
    ld   l,a
    ld   h,0
#endasm
}

void poke(int addr, char value)
{
#asm
    ld   ix,0
    add  ix,sp
    ld   a,(ix+2)       ; value
    ld   l,(ix+4)       ; addr
    ld   h,(ix+5)
    ld   (hl),a
#endasm
}

void outp(char pnum, char value)
{
#asm
    ld   ix,0
    add  ix,sp
    ld   a,(ix+2)       ; value
    ld   c,(ix+4)       ; pnum
    out  (c),a
#endasm
}

unsigned int r;

unsigned char rnd()
{
    r++;
    r ^= r >> 3;
    r ^= r << 5;
    r ^= r >> 7;
    return(r);
}

char buf[144*8] = { 0 };
char balloon[] = { 0x1c, 0x3e, 0x7f, 0xff, 0x7d, 0x3a, 0x1c};
char ribbon[]  = { 0x00, 0x00, 0x00, 0x99, 0x66, 0x00, 0x00};

void main()
{
  int scry = peek(0x790d);
  r=255;

  for(int y=0; y<4; y++) {
    for(int x=0; x<24; x++) {
      putchr(x, y,' ');
    }
  }

  for(int y=0; y<7; y++) {
    outp(0x58, 0x7f);
    outp(0x58, 0xb8+y);
    outp(0x5a, 0);
  }

  while(getcodei()) {}

  while(!getcodei())
  {
    unsigned int oldr=r;

    if (r==255) {
      r = peek(0x7a9c);
    }

    r=rnd()%137;

    for (int y=0; y<8; y++) {
      outp(0x54, 0xc0+scry*8+y);
      outp(0x58, 0xc0+scry*8+y);

      for (int x=0; x<144; x++) {
        buf[scry*144+x] &= (255 - (1 << y));
      }

      for (int x=0; x<7; x++) {
        buf[scry*144+r+x] |= (balloon[6-x] & (1 << y));
      }

      if(oldr<255)
      {
        for (int x=0; x<7; x++) {
          buf[scry*144+oldr+x] |= (ribbon[6-x] & (1 << y));
        }
      }

      if(getcodei())
      {
        break;
      }

      putimg(0, 0, buf+scry*144, 144);
    }

    for (int x=0; x<144; x++) {
      buf[((scry+4)%8)*144+(143-x)] = buf[scry*144+x];
    }

    scry++;
    scry %= 8;
    poke(0x790d, scry);
  }
}