Halo 1 decompilation

This is a work-in-progress decompilation of Halo: Combat Evolved build 2342 (cachebeta.exe, sha256 4cc87b45f721270392a96f1674ed2b5cd4a7bb4355faeab4531d1cf1884d9520).

Agent quick references

• Current campaign house rules and batch/treemap cadence
• Common constants, types, float patterns, tag IDs, and flag conventions
• Shared assertion macros and byte-matching examples
• Supplied CE source maps, recovered names, and next reconstruction packets
• Matching methodology and source-credibility rules

Build instructions

You must source the Halo 1 PAL debug build and the August 2001 Xbox SDK yourself. You also need ninja-build on your PATH.

Extract the XDK/xbox folder from the installer into the repository root such that xbox/{bin,include} are valid paths. Place cachebeta.exe from the Halo 1 build into your repository root. Navigate to the repository and run configure.py in the terminal.

Then, use ninja build to compile the game and report progress statistics, or open the cachebeta.sln VS2022 project under projects on Windows.

Where's all the type information?

We use debug symbols from later Halo games to help map structures, enums, type definitions, function signatures and some variable names. You should obtain a copy of the Halo CEA beta and run it through pdb-decompiler to obtain debug info for yourself. Note that CEA is based off of Halo PC and has its own modifications which make it not 100% accurate to the original Xbox title.