ReaperOfVeriod 379c12f8ec Identify the chunk header as a type ID that determines the record stride
Range measured: all 27 levels, 1123 chunks.

Method: group chunks by their 16-byte header; for each distinct header,
collect the set of strides seen across every level it appears on.

Result: only 64 distinct headers across 1123 chunks. The header is a type
identifier, not a per-chunk descriptor -- the same 16 bytes recur on every
level. And 63 of those 64 imply exactly one stride, so header to record layout
is very nearly a function.

The exception is header 7542eff271b522a79e45348cca4509ff, seen with strides 76,
92 and 104. Either three types share a header or one is a misparse.

This also settles the previous entry's open question about D/E/F being
incidental. Grouping by header bytes 9 and 13:

  DE   26 chunks,   2 strides (184, 344)
  EE 1050 chunks,  46 strides
  EF   34 chunks,   2 strides (268, 640)
  FF   13 chunks,   1 stride  (520)

Rare tags are tightly coupled to their layouts -- FF is a single stride across
all 13 chunks -- while EE is heterogeneous. That is what a type tag looks
like.

Consequence: a chunk can be dispatched on its header to a record layout, and
63 of 64 headers give that layout's size without inspecting a record. First
point in this container where a field does real work rather than correlating.

Still open: what the 64 types mean, which record fields are
index/length/offset, and whether any type is moby_anim.
2026-10-11 04:28:12 +02:00

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.

S
Description
No description provided
Readme
13 MiB
Languages
Rust 98.8%
Python 0.9%
Shell 0.3%