Kid Chameleon Disassembly

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Build Instructions

1. Place a ROM of Kid Chameleon in the main folder, called kid.bin.
2. Run the python3 script split.py to split off game data into separate files.
   • Remark: needs Python >= 3.2. Remove the exist_ok parameters in the code for older versions of python.
3. Run build.bat (Windows) or build.sh (Linux) to build the ROM.

Credits

Saxman727 for the K-E level editor and first hacking notes (docs/Kid Chameleon hacking.txt). Community from the Kid Chameleon Wikia (http://kidchameleon.wikia.com/wiki/Main_Page) for compiling plenty of information about Kid Chameleon. Sonic Retro community, in particular for the Sonic 2 disassembly and plenty of hacking resources for the Sega Genesis.

Details

The split.py script takes most of the data from the ROM and splits it into separate binary files. Thus the code file kid.asm contains almost exclusively assembly code, with data included via include or binclude directives. This disassembly is made for the AS assembler which is included in the build/ folder, and building should work on both Linux and Windows.

The beginning of kid.asm defines some options that can be turned on and off. zeroOffsetOptimization is set to 0 for the sole purpose of building a bit-perfect ROM, and not required otherwise. platforms_asm, when set to 1, includes platform data for each level as .asm file rather than .bin. This is necessary if you want to change length of any platform presets (level/platform_presets.asm). insertLevelSelect, when enabled, inserts a level select into the ROM.

Following these options are constants for various level IDs, as well as for the default options, provided for convenience to make modifications to these easier.

The doc/ folder contains various useful information, including Saxman's original hacking notes, some information on the layout of the ROM and M68k RAM in the game, and data formats.

Data

Most data from the game has been split into separate files. Theme data, such as foreground/background art and mappings, collision, palettes, and titlecard data (art, mappings, palettes) are in the theme/ folder. Level specific data, such as foreground and background layout, block layout, enemy layout as well as background scrolling data, platform definitions and level headers are in the level/ folder. This folder also includes .asm files containing the level order, speed bonuses, path bonuses, level names, as well as platform presets (data defining along which paths certain platforms move). Assets from intro, menu, and intermission scenes/screens are in the scenes/ folder, specifically compressed and uncompressed art, palettes and plane mappings.

Any modifications to these files will be incorporated into the built ROM. Warning: When re-running split.py, all modifications to these files will be overwritten with the original content from kid.bin.

The folder planeed_prj/ contains PlaneEd projects for various plane mappings used in the game, such as title cards, some backgrounds, and menu etc screens. See planeed_prj/readme.txt for more details.

Kid Chameleon uses the GEMS sound driver. All sound assets and the sound driver itself are contained in the sound/ subfolder.

ROMs modified with K-E or K-C

ROMs that have been modified with the level editors K-E or K-C can also be split to be used with this disassembly. These editors create extra space at the end of the ROM, and move the offset table for level headers and all level data there. Thus, in order to split the data, in the split.py script, MapHeader_Index has to be changed to 0x100008 and MapHeader_Offset to 0x100000 before running the script. Furthermore, a few pieces of assembly code have to be replaced. For this, place the modified kid.bin in the folder tools/ and run includes_hack.py which will create a hack/ subfolder. This subfolder will contain a few files with assembly codes and instructions where to put these code pieces.