I tested the wrong switch. SYLPHEED_KF_TIME_SHIFT is a superseded partial fix: it
got the association right but LEFT POSE 0 UNTIMED, which is exactly why the
untimed keyframe appeared to move from last to first. The real correction is the
DEFAULT in the tagged crate, with the old reading behind SYLPHEED_KF_TIME_LEGACY.
So last iteration's five rows measured a mismatch against a knob nobody should
use -- I suspected they were not decisive, I did not suspect the knob was retired.
THE CONSEQUENCE IS MUCH SMALLER THAN I BUDGETED. A placement group is an 8-byte
header then frames x {u32 time; 36-byte pose}, so pose 0's time is the group's
lead-in word and every pose is timed. Measured on the re-export: 866 keyframes,
0 untimed. `pose_at`'s "the final keyframe carries no t, so give it a synthetic
time" premise does not invert, it DISAPPEARS -- dead code rather than wrong code,
which is why nothing needed re-deriving. And the leaf now reads t=0 x=-639,
t=150 x=-39, t=540 x=1521, giving x=781 at t=355: the Decoder's predicted
top-left, and the 1300 px discrepancy is gone.
Pinned by tag, which is what MISSION section 2's tagging rule is for. BLOCKED was
wrong in both directions -- "cannot be taken yet" AND "only when that branch lands
on main". It arrives when the tag is pinned.
COST STATED: sylpheed-cli builds from the workspace crate, so until this reaches
main the exporter and the reference renderer read different decoders and
verify-screen compares two eras. verify-capture is unaffected -- it compares
against oracle captures and never touches the CLI. Revert to the path dependency
when the tag is an ancestor of main.
Oracle: publisher_logo 1.00% -> 0.75%, developer_logos 0.39% -> 0.33%, and
extras' differing region COLLAPSING from 736x525 to 398x295 at the sweep position
-- the residual localised onto the one element still in question. title unchanged
at 1.82%, now posed at t=355, the Decoder's FITTED sweep time. t=390 measures
1.65% and picking it would be fitting the pose to the score.
REFUTED, MINE: "ptlogo_eff2 is the single drawn element at a scale that is not a
whole multiple of 100%". That census was parents-only; the 45 leaves hold
thirteen distinct non-whole-multiple scales and 125% is among the rarest at two.
The claim's real content was "the only one the port draws" -- about my element
set, not the disc.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF
Sylpheed
A clean-room reverse engineering and port project for Project Sylpheed: Arc of Deception (Xbox 360, 2007).
Three things live here, in one repository so that a change spanning them lands as one commit:
| The decoders | crates/sylpheed-formats — the disc's formats, read and verified disc-wide |
| The port | port/ — a Godot 4 project, plus crates/sylpheed-export which converts a disc into the open asset tree it reads |
| The corpus | docs/re/ — what has been reverse engineered, with its evidence, its retractions and its dead ends |
You need your own copy of the game. No game content is in this repository and none ever will be. The exporter reads the disc you supply.
The oracle is the real game
sylpheed-cliand the Explorer are tools for verifying our decoding. They are hypotheses under test and they have been wrong. When something must be checked against the truth, the truth is the game running in Xenia Canary, captured — not any renderer of ours.
This is stated first because getting it backwards is the most expensive mistake this project has made.
Layout
crates/
sylpheed-formats/ the decoders. Disc-wide verified; the corpus is its spec
sylpheed-cli/ headless tools -- render a screen, dump a table, probe audio
sylpheed-viewer/ the Explorer: a human's window onto the disc. STATIC data only
sylpheed-export/ disc -> the open, moddable asset tree
port/ the Godot 4 project. Reads open formats ONLY
authored/ decisions that are NOT on the disc, each with its reason
data/
base/ generated by the exporter. Gitignored, never hand-edited
mods/ drop-in overrides. Yours
docs/
re/ the corpus: findings, refutations, method traps
game/ how the game is navigated -- menus, modals, flight
port/ the port's mission, its handoff contract, modding rules
agents/ how the agent team works together
tools/ capture harnesses, probes, the share tool
exchange/ transient inter-agent files. NOT in git
docker/ the agent containers
Where to start
docs/re/INDEX.md— what is decodeddocs/re/REFUTED.md— what has been tested and dieddocs/re/METHOD.md— traps this project has already paid fordocs/game/navigation.md— how the game is navigateddocs/port/MODDING.md— why the asset tree looks the way it does
Xenia Canary is a separate repository: it is a fork tracking upstream, and it carries our instrumentation.
Conventions
Confidence is per claim, never per document: ✅ CONFIRMED · 🟡 PROBABLE ·
❔ HYPOTHESIS · ❌ REFUTED. A withdrawn result is kept with its reasoning
rather than deleted — that is why the numbers here can be trusted.