skate-3-rust-engine/tools/recomp-trace/README.md

Recomp trace analysis

For use with the Skate 3 recomp's research hooks: Hailey-Ross/skate3recomp, branch research-hooks (described in docs/hails-additions/13-recomp-research-hooks.md).

Reference only. These scripts read traces written by that branch's hooks. You must build the recomp yourself (from your own legally owned copy of the game), apply its SDK patch, and set up the trace paths and the paths below for your machine. The recompilation is not a perfect copy of the console game: it runs uncapped, and its timing and threading differ. Treat logged values, data and program logic as evidence; treat timings and per-frame rates as specific to the recomp.

The hooks write a tab-separated trace.tsv (KIND <tab> <ms> <tab> fields…, all on one time base), optionally a float32 stereo capture of the mixed output, and screenshots. A session folder holds trace.tsv (and trace.f32 / audio.f32, shots/).

Script	What it does
trace.py	Shared reader (from trace import Trace): lines per kind, MARK stops, screenshot nearest a time, capture windows. Run alone: line counts per kind, malformed fixed-layout lines (should be zero), stops.
first_pass.py	Summarises first-pass raw-register hook lines per kind: call counts and the distinct values of each register, so constant fields (pointers, flags) stand apart from data.
resolve_trace.py	Finds each played sample's payload in your own disc's audio archives and names the bank member and stream. Used by retail_voices.py.
retail_voices.py	Joins each voice's PLAY with its MOD (pitch, filters), GAIN and SEND lines: per bank, voices, pitch / rate quantiles, filter cutoffs and level. --csv per voice; --modules lists the buses. Caches resolutions in the session folder.
retail_relay.py	How one emitter bank's voices follow each other: starts, slots, pitch, gaps, overlaps, repeats and the most voices at once. Needs play_resolve.json from retail_voices.py.
grec_level.py	Grain-bed (rolling) levels from GREC lines per speed band: straight rolling and carving.
grec_clean.py	Grain-bed gain on clean straight rolling only (settled, no brake / push / balance / trick), per speed band and truck.
grec_material.py	Wheel material against wheel count from GREC lines: how often the material changes while rolling, and how often it reads the "no contact" value.
send_vectors.py	Per-channel send gains from SEND lines: power sums, LFE share, most common pan shapes.
grain_trace_stats.py	Grain voice starts (PLAY lines matching a .grain member of your disc): starts per member, per second and inter-start intervals.
retail_windows.py	Straight four-wheel rolling windows of the session's capture per 5 km/h band (level, octave bands), next to the engine's e2e renders folded the same way (tools/audio-e2e).
veh_trace.py	Traffic summary from the traffic hook lines: per vehicle speed, target speed, manoeuvre and lane changes, stops, plus the horn / skid / engine lines.
bail_impacts.py	Per bail (BAILSTEP / BAILREG lines): the ragdoll's update interval, then per body region the impacts the game wrote, the per-update velocity change along the contact normal (percentiles), whether the largest ones are contact stops or drives, and the body / cloth / concrete sound posts in the bail. Flags hitches over 40 ms.
collision_posts.py	Collision-sound posts (COLLPOST) split into bail windows and the rest, per posting function and owner: rates, material pairs, tiers and the local-rider flag (local72), so the player's own sounds can be told apart from NPC skaters' and props'.

Inputs

• A session folder or trace.tsv from the research-hooks build.
• Your extracted disc for resolve_trace.py, retail_voices.py, grain_trace_stats.py: --disc DIR (the folder holding data/), default $SKATE3_DISC or .local/skate3-disc.
• An installation's decoded banks for retail_relay.py (--assets, default assets).
• Hook-specific values that depend on your build are inputs, not built in: e.g. retail_windows.py --contact-callers (the caller prefixes of the board-contact SPLC lines in your trace).

Usage

py -3.13 tools/recomp-trace/trace.py sessions/my_session/trace.tsv
py -3.13 tools/recomp-trace/retail_voices.py sessions/my_session --bank SomeBank --csv voices.csv
py -3.13 tools/recomp-trace/retail_relay.py sessions/my_session SomeBank --from 60000 --to 120000
py -3.13 tools/recomp-trace/grec_level.py sessions/my_session/trace.tsv
py -3.13 tools/recomp-trace/retail_windows.py sessions/my_session .local/audio-e2e --contact-callers 82AAAA,82BBBB
py -3.13 tools/recomp-trace/first_pass.py sessions/my_session/trace.tsv SOMEKIND
py -3.13 tools/recomp-trace/bail_impacts.py sessions/my_bail_session/trace.tsv
py -3.13 tools/recomp-trace/collision_posts.py sessions/my_ride_session/trace.tsv --top 6

Both refuse a trace with malformed lines of their kinds (record again rather than parse around bad data). Before comparing collision-sound rates with another engine, filter to the local rider (local72 = 1): NPC skaters post into the same manager.

Example output

trace.py (made-up counts):

{'MARK': 12, 'PLAY': 5400, 'MOD': 31000, 'GAIN': 18000, 'CAPTURE': 900}
malformed (fixed-layout kinds): {'TREAT': 0, 'SEAMPAT': 0, 'SEAMHIT': 0, 'GRECX': 0, 'FIRSTHIT': 0, 'SKID': 0, 'EMITSLOT': 0}
stop_a                           12.0 ..     95.5 s

Requirements

Python 3.13; numpy for retail_windows.py and Trace.capture. The repository's tools/owned_game and tools/asset_pipeline/audio_formats.py for the resolvers.