ReaperOfVeriod
681333535a
gc_formats::chunks parses the container that fills the region after the last shrub class body and before the constant trailer: +0x00 16 bytes, last byte 0xff (opaque, differs per chunk) +0x10 10 zero bytes +0x1a N tagged offsets, top byte 0xf0 Each tagged offset is 0xF0000000 | low24, and a record is read at chunk_start + low. Resolving that way gives records sharing a field layout, which is what distinguishes the container from a coincidental byte pattern. Fields are not named. The 16-byte header is opaque, the 0xf0 tag is unexplained, and it is not established that a chunk is moby_anim -- a 49 x 368-byte table inside this region is byte-identical on all 27 levels, which is evidence against that identification. What the parser provides is chunk and record extraction, which is what the analysis established. The gated test measures, over all 27 levels: 1123 chunks, 19546 records, 50 distinct strides, 12.4% of byte positions constant across records (per-chunk range 2.8% to 75%). Chance gives a constant position probability of 1/256^n. Three things the test got wrong first, recorded because they are the traps: - A per-chunk threshold of 20% constant positions. Individual chunks run from 2.8% to 75%; the aggregate is the invariant, not the chunk. Asserting 20% per chunk was asserting a property the format does not have. - Requiring every offset to resolve. 27 chunks truncate at the window edge, because the 900000-byte window does not align to chunk boundaries. Counted now rather than asserted away. - read_u32 in the chunk signature check was big-endian while Buf::u32 is little-endian. The tag lives in the high byte of a little-endian word, so the mismatch made every level report zero chunks while parse_chunk -- which goes through Buf -- was correct. Worth remembering that the two paths can disagree on a format this young. Tests: 190 -> 191.
Going Commando
A native PC reimplementation of Ratchet & Clank: Going Commando (PlayStation 2, 2003), written in Rust.
The game is reimplemented, not emulated. There is no MIPS interpreter here and no CPU emulator: the systems are ported to Rust so they run as ordinary native code.
Status: initial scaffold. The disc is identified and verified, the
workspace builds, and nothing else is implemented yet. See
docs/roadmap.md for where things stand and what comes next.
The target
| Game | Ratchet & Clank: Going Commando |
| Platform | PlayStation 2 |
| Disc | SCUS_972.68 v1.01, USA Black Label |
| Video | NTSC, 60 Hz |
| Boot ELF SHA-1 | bacda860cbd6723142e86db56f197e47e728970f |
Verified against a real disc — see docs/disc-identification.md.
This is the build the reference projects pin; Greatest Hits v2.00 is a
different binary and is not the target.
No game content
This repository contains no game assets, no disc images, no BIOS dumps and no proprietary toolchains. You supply your own legally obtained copy of the disc as an input, the way the upstream reference projects do.
A pre-commit hook enforces this, blocking disc images, asset directories, container signatures and files over 50 MiB. If you clone elsewhere, enable it:
git config core.hooksPath .githooks
Layout
crates/
gc-formats/ asset format parsers (pure, no I/O beyond the caller's buffer)
gc-extract/ disc pipeline: identify, unpack, verify
gc-game/ game logic: hero, weapons, moby classes, progression, saves
gc-video/ IPU / MPEG-2 decode
gc-engine/ Bevy app: Graphics Synthesizer, VU0/VU1, renderer, frame loop
docs/
disc-identification.md which disc we build against, verified
roadmap.md phases, gates, current status
plan/ one file per subsystem, written as work proceeds
formats/ format specs, written as formats are reversed
tools/
identify-disc.py identify any Going Commando disc image
vendor/
rerac/ pinned upstream reference checkout (not tracked)
Building
Requires a Rust toolchain via rustup.
cargo check --workspace
cargo test --workspace
The host audio backend is disabled in Cargo.toml (see the comment there) so
that the workspace builds without system ALSA development headers. Audio decode
is the last phase of the port and lives in gc-video; re-enable it and install
alsa-lib-devel when that work starts.
Identifying a disc
python3 tools/identify-disc.py <your-disc.iso>
Reports the serial, version and video mode from SYSTEM.CNF, hashes the boot
executable, and warns when the disc is not the supported build. Reads only a
few megabytes, so it is near-instant.
How it will be verified
Visual and behavioural comparison against PCSX2, replaying recorded input and
comparing frames, level by level. The PS2 float model is reproduced rather than
approximated — see AGENTS.md.
Credits and licensing
This project learns from and is built on the work of others. Licences are
recorded in PROVENANCE.md and notices must travel with any
code derived from them.
- ReRAC — a native Rust/Bevy port of Ratchet & Clank (2002), the first game. ISC. The architecture this project follows.
- OpenRAC / rac2-gc-decomp — matching decompilation research for this game. MIT. Source of verified struct layouts and engine documentation.
- Wrench — community documentation of Insomniac's container formats. GPL, used as a specification reference only; no code is copied.
Ratchet & Clank is a trademark of Sony Interactive Entertainment. This is an unofficial fan project, not affiliated with or endorsed by Sony Interactive Entertainment or Insomniac Games.