The Decoder overturned the elimination I was most confident about. I ruled out
the ptloop sweeps because "399x180 at (441,270), keyframes hold position
constant". That is the PARENT's record. The geometry is in the leaf.
ptloop01 parent: scale (100,100) rot 0, fixed at (441,270)
LEAF: scale (100,600) rot +30, x sweeping -639 -> -39 -> 1521
ptloop02 parent: scale (100,100) rot 0, fixed at (441,270)
LEAF: scale (100,800) rot -45, x sweeping 1721 -> 1111 -> -839
Two ~1080 and ~1440 px quads leaning opposite ways and sweeping across the frame,
against two 400 px sprites drawn upright and static in the middle. That is
exactly the signature I measured -- darker centre-left, brighter right, nearly
cancelling -- and the GPU capture puts their centres at x ~ 467 and 992, the two
cells where my signed difference peaked.
`ui_layout`'s own doc comment said it: "the rotated quads come from its two
nested .rat leaf records, which the census never opened". Neither did this
exporter -- it opened a leaf in exactly one place, `highlight_name`, for focus
records.
IT IS NOT TWO ELEMENTS, IT IS 45: every button on every menu (the benign case,
where screen.rs already knew the leaf duplicates the parent and the parent wins),
the four loading screens' pgloading_loop*, and title_jp's ptlogo_eff2 -- which is
the element DECISIONS has recorded since P1 as the largest render disagreement in
the export, and which has a TWO-element leaf. A lead, not a conclusion.
EMITTED, DELIBERATELY NOT DRAWN. One `read_leaf` closure serves both the new path
and the focus path, because a second copy is how this would go missing again.
ScreenView ignores the data: parent and leaf each carry their own alpha ramp over
a different span (parent 0->255 over t=70..238, leaf 255->0x80->255 over
t=150..600), so how they compose is a decoding question, and drawing on a guess
would replace a visible 1.82% gap with an invisible wrong one. verify-screen
confirms nothing moved.
Additive blending is refuted -- the Decoder tested T8aD +0x04 bit 0x02 and "every
measure worsens", and the export carries no blend field because none has been
found (no RB_BLENDCONTROL in the per-draw capture). My hypothesis from last
iteration is dead.
This makes the port's biggest oracle gap the same item as the rotation question
already standing with the human: sylpheed-cli deliberately does not rotate, which
is why both renderers show it, and MISSION's "Needs a human decision -- rotation"
now has a number: 1.82% of the title's pixels.
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.