Tobias V. I. Langhoff tobiasvl

In the past few years, it seems that, as retro gaming has grown in popularity, programming for older platforms has also gained traction. A popular platform is the Game Boy, both for its nostalgia and (relative) ease to program for.

When someone wants to make their own game, one of the first problems they will encounter is picking the tools they will use. There are two main options: either use GBDK (Game Boy Development Kit) and the language C, or RGBDS (Rednex Game Boy Development System) and the Game Boy's assembly language.

The purpose of this document is to provide my insights and experience, and help you make the better choice if you're starting a new project. I will also provide some "good practice" tips, both for C and ASM, if you have already made up your mind or are already using one of these.

	get_map_position:
	; from a sprite's pixel position, get the BG map address.
	; d: Y pixel position
	; e: X pixel position
	; hl: returned map address
	ld h, HIGH(_SCRN0) >> 2

	; Y
	ld a, [rSCY] ; account for scroll
	sub a, 16 ; account for base sprite offset

	-- initialize a save file holding a `savedata` sequence
	function init_savedata()
	local info=love.filesystem.getInfo("savedata.lua", "file")
	if info then
	local data=love.filesystem.read("savedata.lua")
	savedata={love.data.unpack("f",data,1)}
	else
	local file=love.filesystem.newFile("savedata.lua")
	local ok,err=file:open("w")
	if not ok then

	pico-8 cartridge // http://www.pico-8.com
	version 4
	__lua__
	player = {}
	player.x = 5
	player.y = 5
	player.sprite = 0
	player.speed = 2

	function move()

	# based on http://voidptr.io/blog/2017/01/21/GameBoy.html

	# Simple makefile for assembling and linking a GB program.
	rwildcard = $(foreach d,$(wildcard $1),$(call rwildcard,$d/,$2) $(filter $(subst ,%,$2),$d))
	ASM := rgbasm
	LINKER := rgblink
	FIX := rgbfix
	BUILD_DIR := build
	PROJECT_NAME ?=
	OUTPUT := $(BUILD_DIR)/$(PROJECT_NAME)

	; C000 = Copy of OAM table

	InitSpriteDMA::
	; copy spritedma routine into hiram
	ld hl,SpriteDMA
	ld de,$FF80
	ld bc,SpriteDMAEnd - SpriteDMA
	call mem_Copy
	ret

	#! /local/bin/python
	# vim: set fileencoding=utf-8 :

	# Generelt oppsett
	import rlcompleter
	import readline
	import code

	from mx import DateTime

	Cerebrum/Constants.py:# This is probably a hack that is done to make makedb create and update
	Cerebrum/Database.py: # Not sure that this is the proper default, but as a quick hack it
	Cerebrum/Database.py: dictionary to the backend's execute(). This hack implies a performance
	Cerebrum/Database.py: # Translate Cerebrum-specific hacks ([:]-syntax we love, e.g.). We
	Cerebrum/Database.py: The class is a hairy monstrosity of an enormous hack. SQLite does NOT
	Cerebrum/Database.py: """SQLite-specific cursor hacks.
	Cerebrum/Database.py: # Since sequences are not supported, we have to hack around them
	Cerebrum/Database.py: Hmm... a fix of a patch of an extension of a hack. This is badly
	Cerebrum/Person.py: # such a more correct change, we'll live with this hack.
	Cerebrum/Person.py: :param ret_primary_acc: Hack to make person_id become account_id.

	Aug 07 21:22:50 rocinante.uio.no systemd[1]: Starting dnf makecache...
	Aug 07 21:22:53 rocinante.uio.no dnf[29990]: Fedora 26 - x86_64 - Updates 30 MB/s \| 9.5 MB 00:00
	Aug 07 21:22:53 rocinante.uio.no dnf[29990]: Last metadata expiration check: 0:00:00 ago on Mon 07 Aug 2017 09:22:53 PM CEST.
	Aug 07 21:22:53 rocinante.uio.no dnf[29990]: Metadata cache created.
	Aug 07 21:22:54 rocinante.uio.no systemd[1]: Started dnf makecache.
	Aug 07 21:22:54 rocinante.uio.no audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=dnf-makecache comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=?
	Aug 07 21:22:54 rocinante.uio.no audit[1]: SERVICE_STOP pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=dnf-makecache comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=?
	Aug 07 21:30:01 rocinante.uio.no CROND[30357]: (root) CMD ( systemctl -q is-active cf-execd.service \|\| sy

Tobias V. I. Langhoff tobiasvl

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