ac1371cda3
The sweep starts early because ScreenView drew a leaf WITHOUT multiplying its
parent's alpha in. ptloop01/ptloop02 declare 0:0 70:0 100:255 238:255 250:0, so
the sweep is invisible until t=70 and full at t=100. The port has had that ramp
in its export the whole time and was throwing it away at the draw call.
Three changes:
1. Parent alpha multiplies into the leaf's. This file asserted the opposite,
arguing from the sweeps being drawn while their parent had expired -- but that
could not separate 'the leaf wins' from 'the parent is ignored because it
draws nothing', and its own comment said so and named the interval that would
settle it. Measured there: dividing the leaf's declared curve out of the drawn
alpha pins the implied parent at 255.0 (+/-1.5) over hundreds of frames while
the drawn alpha swings 242 -> 132 -> 145.
2. rate 0.5, calibrated against a DECLARED interval (ptloop01's own 30-unit ramp)
rather than captured frames: two runs differing 2x in frames give 0.4795 and
0.4667, 2.7% apart. This number was 0.514, withdrawn, now reinstated at 0.5 --
what failed the first time was quoting a rate in presents, and the ratio was
discarded along with the frames.
3. The 107-unit authored offset is DELETED, with its guard tool. It came from a
ratio measured against an element identified only by screen position; the
declared ramp needs no such identification. Deleting an authored value because
the data already says it is the outcome PORT-MISSION asks for.
Also reverted, same day I made it: removing the transparent-parent skip. I read
'the game submits the sweep ~950 frames past its parent's expiry' as the leaf
outliving the parent. It does not follow -- a draw submitted at alpha 0 is still
a draw, and submitted is not visible. With the multiply, skipping on a
transparent parent IS multiplying by zero.
VERIFIED, pre-registered before running, via --probe-leaf:
u= 60 -> no draw at all (predicted: parent alpha 0.00, gated off)
u=100 -> leaf_t 50.0, x -439 (predicted 50.0, -439)
u=236 -> leaf_t 118.0, x -167 (predicted 118.0, -167)
verify-capture: every row unchanged.
⚠️ BUILD-SENSITIVE: builds 5 and 6 of GP_TITLE declare these records as a single
flat a=255 with no ramp. This export reads the ramped build; if that changes the
gate disappears silently.
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
-- and RUNNING.md, which is how you actually start it
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.