ReaperOfVeriod
bc5ebe559f
Having established that i16[0..2] are positions, ran the same LOD-overlap method
across all eight slots to see whether it discriminates elsewhere. It does not,
and that is worth recording before someone reads the passing numbers as nine
confirmations:
slot same class control ratio
i16[0] 97.0% 3.0% 32x
i16[1] 96.7% 3.2% 30x
i16[2] 96.4% 6.0% 16x
i16[3] 75.3% 78.7% 1x
i16[4..7] 68-91% 52-79% 1x
Only i16[0..2] carry signal, because they are the only slots with tens of
thousands of distinct values. The rest draw from sets of 226 to 1,759 values, so
any two sets of that size overlap heavily regardless of what the field means. A
passing result from a method that has run out of discriminative power is not a
passing result.
Slot 3 excluded as a skin/joint index. It holds 201 values in 0..=254 and 50
distinct values within a single draw packet, so it is per-vertex, not per-material
-- which invites the obvious reading, since tie objects are skinned. Wrong:
mean pairwise distance, same slot-3 value 14,481
mean pairwise distance, different slot-3 value 13,795
ratio 0.95x
control: same position-x bucket 8,105
Vertices sharing a slot-3 value are marginally FARTHER apart than vertices
differing in it. The control halves the distance, so the measurement works; the
0.95x is on the wrong side of neutral, though by too little to claim much on its
own. Combined with no LOD sharing (75.3% against a 78.7% control), slot 3 is
per-vertex, uncorrelated with the geometry it sits in and with the detail level.
Recorded as not understood. A per-vertex animation phase fits the arithmetic and
is labelled a guess rather than offered as a reading.
Slots 6 and 7 are mostly not per-vertex. Distinct values per draw packet, median
over 1,804 records:
i16[0..2] 13-17 constant for the whole packet 0%
i16[4,5] 6, 4 0%
i16[6] 2 43%
i16[7] 4 34%
They take a single value across an entire packet in well over a third of records,
which matches the 91.8%/88.9% dominance of 4096 and 0. Unnamed.
So the tie element is: position, byte-sized index, texcoords, layout tag, and two
slots characterised but not named. Positions, texcoord placement, element size and
the layout selector are all asserted; the remaining three are not, and the reasons
they are not are now written down rather than left as silence.
On "is Phase 2 nearly done": 40 items closed, 9 open. The nine are the hard
ones -- collision cells blocked on the game's own code, volumes not located at
all, moby_anim ruled out but unexplained, chunk record fields unnamed. Progress
on the checklist is real but the remainder is not the easy tail.
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.