ReaperOfVeriod
c60340b1de
The claim that the post-shrub region has a 368-byte period throughout is wrong. Re-measured over the whole region the curve is flat and near noise: stride 8 +0.027 stride 12 +0.023 stride 148 +0.009 stride 340 +0.018 stride 368 +0.018 stride 632 +0.020 Nothing peaks at 368, and the 0.1110 recorded earlier does not reproduce under any sampling convention tried. Where the structure is: scanning 8 KB windows at 1 KB steps for a 368-excess above 0.15 finds one substantial region, region+41984..+57344, 15360 bytes, plus a 4 KB patch at region+650240. Within that window 368 is unambiguous -- +0.315 against +0.284 at 736, with 364, 372 and 732 all at noise. 41 whole records, mean 16 distinct values per position, and nine positions exactly constant and zero: 329-336 and 340. Twenty-five positions have 3 or fewer distinct values, clustered in 325-349, which is a tail rather than scattered padding. Corrected statement: a 15360-byte window of the post-shrub region is a table of 41 records at stride 368, each with a roughly 43-byte tail whose fields are mostly zero. The surrounding 675 KB is not that table. What went wrong before: the original measurement was taken over a window where 368 held, then reported as a property of the region. That window holds 41 of 1841 records, and averaging it over the region flattens the peak to the noise floor. The re-verification checked the stride but not whether it applied uniformly, so it confirmed the number without testing the claim attached to it.
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.