OpenCMR2

Appearance

OpenCMR2Colin McRae Rally 2.0, reimplemented

A faithful reimplementation of Colin McRae Rally 2.0 (Codemasters, 2000) in C11, ported function by function from the Windows game. It runs the game from your own CD, as one WebAssembly module for the gasm runtime, natively and in the browser. Early in the port: nothing is playable yet.

Get started
Port plan
Status

Faithful

Not an emulator and not a remake. The goal is the original's behaviour, its 16.16 fixed-point handling model, co-driver, AI and quirks included, ported from CMR2.exe.

Your own data

Reads your CD or its image. Even the tables inside the original program are read from your copy at run time. Nothing from the game is in OpenCMR2.

Game data

Runs on gasm

One opencmr2.wasm for macOS, Linux, Windows and the browser on the gasm WebAssembly game runtime. The original's Direct3D 7 rendering goes to OpenGL ES 3.0 (WebGL 2 in the browser).

Running on gasm

Reverse engineered in the open

The architecture of the original program, its function map and the formats of every file on the disc are published with the code.

Reverse-engineering notes

Every format, documented

The gzip/CMPR containers and archives, PP_F models, stages, cars, DXT5 textures, MS ADPCM music, Bink movies, text and fonts.

File formats

A plan, step by step

Eleven steps from the file layer to network play, each ending with a check that runs headless against your data.

Port plan

Built for gasm ​

Built for gasmBuilt for gasm

OpenCMR2 will be one WebAssembly module, opencmr2.wasm, running on gasm, a portable game runtime: the same module natively (gasm-run) and in the browser. See Running on gasm.

Status ​

The disc and the program are analysed and the plan is written. Steps 1 and 2 are done: the file layer runs on gasm from the CD or its image, the installer cabinet included, and every texture, sound, font, text table and model on the disc decodes. Details in Status.

Sibling projects ​

OpenCMR2 follows the conventions of OpenRF (Return Fire) and OpenNFSPU (Need for Speed: Porsche Unleashed): a portable C11 core, ported from the original executable, on gasm.

OpenCMR2 is released under the GPL-3.0. Colin McRae Rally 2.0 is © 2000 The Codemasters Software Company Limited. OpenCMR2 contains no original code or assets and is not affiliated with Codemasters: it runs the game from your own copy. It runs on gasm.