ReaperOfVeriod
18af702420
Followed the chain through -- dispatch table to handler address to disassembly --
and read level 0's class 2 handler at 0x00380a88:
0x00380a84: jal 0x2ee0d0
0x00380a88: .word 0x0240202d <- VU1 microcode, not a failure
0x00380a8c: lwc1 $f12, 0x40($s1)
0x00380a98: addiu $a0, $s0, 0x20
0x00380aa0: swc1 $f0, 0x18($s4)
0x00380ab0: swc1 $f0, 0x14($s4)
Floats out of one structure, written back into another, with VU1 work alongside --
what a transform update should look like. The chain from an asset observation to the
game's own code is now complete and usable.
TWO CAVEATS, both learned by hitting them:
VU1 microcode interleaves with CPU code. 0x0240202d is a COP2 opcode, not an
undecodable word. A tool that counts .word lines as failures is counting the wrong
thing -- a trap I walked into earlier today with the region walkers, now recorded
so it is not repeated.
Handlers are not all independent functions. Level 0's class 2 is at 0x380a88 and
class 0x0E at 0x380a90 -- EIGHT BYTES apart -- and 72 of the 5,788 records sit
within 16 bytes of the one before them. Consecutive classes share one routine with
per-class entry points inside it, so reading "a handler" gives a fragment. That
matters downstream: a class's behaviour is not one function, and assuming
otherwise would misattribute shared code.
A DISCREPANCY WITH THE REFERENCE
The decomp reports 5,598 of 5,788 moby handlers (96.7%) preceded by a jr ra within
three words. Measured here, the same way, over the same 5,788 records: 5,488
(94.8%). Same population, same test, 110 handlers different.
Both figures support the premise, so nothing turns on it, and I am recording it
rather than picking the number that suits. The reference measured on 2026-10-02
against its own pinned overlay set, so a method or version difference is as
plausible as a data difference and there is no basis here for saying which. The
test asserts the premise (>90%) and deliberately NOT either exact figure.
Asserted in moby_handlers_are_overwhelmingly_function_entries.
264 tests.
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.
PCSX2 is installed and working on this machine; the comparison loop that reads
the game's own memory over its debug protocol is up, and level 0's and level
1's tfrag lighting are verified byte-exact against it. See
docs/plan/pcsx2-verification.md for the
setup and how to run it.
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.