ReaperOfVeriod
81ec17857a
Picked Phase 3's GS item and did the part that is checkable without a GPU -- the rule layer the renderer will have to feed wgpu. New gc_formats::gs with three of the four rules the roadmap names, each unit-tested. alpha_to_8: 0x80 IS OPAQUE. The obvious implementation of this is let v = value & 0x7F; and it is wrong, because 0x80 & 0x7F is 0 -- which is precisely the mechanism that makes a 7-bit alpha read as "half" to anything treating the byte as 8-bit unsigned. The first version of this function did exactly that and the test caught it. Below 0x80 the value is genuinely 7-bit and scales onto 1..255, so 0x7F is opaque too and no non-zero alpha vanishes. clamp01: CLAMP wrap, with 1.0 kept AT the far edge rather than wrapping to 0. Under repeat sampling an exact 1.0 is a discontinuity; under clamp it is the edge texel, and the game loads its textures that way. mip_level: round(log2(image / on_screen)) clamped to the chain. The ratio is image-over-screen and not the reverse -- a SMALLER on-screen size selects a HIGHER mip level. I had this inverted in the first version, which made mip_level(1.0, 64.0, 8) return 0 where it must return 6, and the test caught that too. Both bugs were the same kind: a plausible implementation of a rule whose sign convention is not obvious, and the only thing standing between them and a commit was the test. Not started: wgpu itself, and blend/alpha-test behaviour. This is the rule layer only, and the roadmap item stays [~] rather than being ticked, because three of four rules and zero of the GPU work is not "done". Two of the four rules the item names were already half-present in the renderer -- moby alpha and the 1/4096 UVs -- so making them explicit here rather than scattered is worth something on its own: 0x80's meaning was previously implicit in however each call site happened to read the byte.
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.