ReaperOfVeriod
027373e65b
Phase 1 of the roadmap. The disc is now turned into verified asset files, and
the result is checked against a committed hash table rather than against
whatever happens to be on disk.
gc-extract identify disc.iso SCUS_972.68 v1.01 NTSC, ELF SHA-1 matches
gc-extract unpack disc.iso out/ 5135 files, 4,500,106,960 bytes, 10.8s
gc-extract verify out/ table.tsv OK: 5135 files match
All 92 G/*.WAD containers parse. MPEG1 and MPEG2 are raw video and pass
through whole; the other 90 are indexed containers whose extents are extracted
individually.
Formats recovered and written up in docs/formats/:
- iso9660.rs. R&C2 lists its assets in the filesystem, unlike R&C1, so a
directory walk is the primary asset index. Three details that all fail
quietly rather than loudly: directory records store every 32-bit field twice
(little-endian then big-endian), the CD001 signature is at sector offset 1
rather than 0x8001, and the directory flag at record offset 25 is
authoritative where the identifier's trailing slash is not.
- global_wad.rs. Container headers hold a table of extents. All 92 indexed
containers use {offset in sectors, size in bytes}. Measured, not assumed: the
sector-count reading places every entry of all 27 LEVEL<n> and all 27
AUDIO<n> containers out of range, while the byte reading places all of them
correctly. SCENE<n> is the one exception, a flat sector list whose extents
are sized by the next value.
- wad.rs. Insomniac's LZ77 stream: four flag-selected packet classes, with 0-3
trailing literal bytes per packet carried in unused low bits. This is not a
bit stream, which is why it resists the usual LZ77 reading.
- buf.rs. A bounds-checked reader, so untrusted 2003 disc data produces typed
errors rather than panics.
gc-extract carries the three stages and a SHA-1 implementation with FIPS 180-4
test vectors, so identification works without pulling in a crypto dependency.
Verification: 54 unit tests, plus four integration tests that run only when
GC_DISC names a disc. Those four check identification against the recorded
values, cross-check the Rust identifier against tools/identify-disc.py, parse
all 92 containers, and confirm a full unpack matches the committed table. The
committed table is 316 KB of sizes and SHA-1s for all 5,135 files: hashes only,
no game content, so it is safe to version and it turns "matches retail" into
something a test can assert.
docs/plan/disc-pipeline.md records two wrong turns, because both are easy to
repeat and both failed by producing plausible wrong output rather than an
error: the container table was read backwards, and the LZ77 stream was modelled
as a bit stream. The first survived because it happened to be correct on the
one container used for manual checking.
38 lines
2.0 KiB
Rust
38 lines
2.0 KiB
Rust
//! Game logic for *Ratchet & Clank: Going Commando* (PS2).
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//!
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//! The rules, systems and behaviour of the game, reimplemented from the
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//! original code rather than wrapped around it. No emulation, no interpreter:
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//! this is a Rust implementation that is meant to behave the way the game does.
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//!
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//! # What belongs here
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//!
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//! * `hero` - Ratchet's controller. Movement on a **spherical** planet, which is
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//! what distinguishes this game: the camera and collision code change gravity
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//! handling across the whole world, and is the main reason the first game's
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//! movement code does not transfer.
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//! * `chargeboots` - hold and release timing, chained jumps and the dash.
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//! * `weapons` - the wrench and the weapon set, plus the weapon modification
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//! system (per-weapon bitmasks: lock-on, shock, acid, ...).
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//! * `gadgets` - the Pyrocitor, Bomb Glove, Glove of Doom and friends.
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//! * `moby_update` - the per-class update dispatch, driven by each level's
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//! `lvl.vtbl` class table. Classes that are identical across levels are
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//! shared; the rest are resolved through the overlay relocator in
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//! `gc-formats`.
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//! * `collision` - queries against the collision world.
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//! * `progression` - bolts, the Gadgetron vendor, RPG upgrades and unlocks.
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//! * `save_game` - the IFF chunk save format, and importing a Ratchet & Clank
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//! (2002) save to unlock the legacy weapons for free.
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//! * `memcard` - the 25-state memory-card finite state machine and its UI.
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//!
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//! # The float model
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//!
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//! The Emotion Engine's FPU is not IEEE-754 in every respect: it has no
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//! denormals, and rounding differs in places. Gameplay code here reproduces
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//! that model rather than using Rust's native `f32`, because the difference is
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//! visible in the movement and the camera. See `docs/plan/float-model.md`.
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//!
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//! # Timing
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//!
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//! The game is 60 Hz (this disc is NTSC). Constants are expressed per tick at
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//! that rate. PAL discs run 50 Hz and would need different timing throughout.
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