Sonic Advance 2

⚠️ This project is not completed and still under active development

This is a work in progress matching decompilation of Sonic Advance 2

It builds the following ROMs:

• sa2.gba sha1: 7bcd6a07af7c894746fa28073fe0c0e34408022d (USA) (En,Ja,Fr,De,Es,It)
• sa2_europe.gba sha1: b0f64bdca097f2de8f05ac4c8caea2b80c5faeb1 (Europe) (En,Ja,Fr,De,Es,It)
• sa2_japan.gba sha1: dffd0188fc78154b42b401398a224ae0713edf23 (Japan) (En,Ja,Fr,De,Es,It)
• sa2_japan_vc.gba sha1: 2aa6ee2cf2b0ebfafbea6d6d24165b252a7e329e (Japan) (En,Ja,Fr,De,Es,It) (Virtual Console)
• sa2_beta.gba sha1: 3368642fc4157824af63367e2a685b7d6ee9b09d (USA) (Beta) (2002-10-25)

It can also build:

• sa2.sdl make sdl (Linux/MacOS SDL 64bit port)
• sa2.sdl_win32.exe make sdl_win32 (Windows SDL 64bit port)
• 🚧 sa2.win32.exe make win32 (Win32 native port, not functional)

Current state

• 🎉 The build is 100% from C files with ~60 functions which currently don't match
• All assembly code extracted, disassembled, and decompiled by hand to their C equivilent
• All songs have been extracted, and documented as matching MIDI files
• All sprite animation frames have been extracted to PNGs and are used to build the matching rom
• All tilemaps (backgrounds) have been documented and had their tiles extracted
• Most aspects of core game play have been documented, but >600 functions are still unnamed
• The game compiles to a widescreen port (426x240) for multiple platforms

Sub games

Within the Sonic Advance 2 rom there are some "Sub games" which we have begun to decompile as part of this project. These sub games are automatically compiled and bundled during the main build process, as they are necessary to create a matching binary.

Multiboot rom	Decompilation
mb_chao_garden.gba
collect_rings.gba

Setting up the repo

Please see follow these instructions

Community

Join us on discord to get started in helping out

Screenshots

Notes

• The Kirby & The Amazing Mirror decompilation uses a very similar codebase, as it was written by the same dev team (Dimps)
• https://decomp.me is a great resource for helping to create matching functions
• ldscript.txt tells the linker the order which files should be linked
• For more info, see the FAQs section of TMC

Credits

• JaceCear for his dedication to understanding the internals of the graphics engine, writing tools to extract this data, as well as massive effort in contributing towards the decompilation process, and setting up the PC ports

• Shout out to @froggestspirit for the drive to set this project up

• Special thanks to @normmatt for the initial repo setup and sounds disassembly

• Pokemon Reverse Engineering Tools community for their help with the project, and tooling for GBA decompilations

• Kermalis for their tool which was used to dump the game midis

• 琪姬 for their exellent work documenting all the quirks of matching midis