82b20bc51d
sylpheed-port proposed that a screen declaring a full-screen .prm at t=0 with fade == 0xff000000 is standalone, and one without it is composited: 12/4 across their sixteen exported screens, every exception independently known to be composited. They asked for it against archives they do not have. That is my lane. CONTROL: the predicate reproduces their split exactly. GP_TITLE's sixteen bundles give 12 with and 4 without, the four without being entries 0, 1, 2, 3 -- build_00, build_01, press_start, press_start_jp -- and the element names match (pteff00.prm, palogo_eff0.prm, pgloading_eff00.prm). Independent derivation from the disc, not a re-run of their tool. DISC-WIDE it is rare: 76 of 965 screen builds, 7.9 %. GP_STAGE_CLEAR 4/4, GP_SYSTEM 2/2 and GP_TUTORIAL 2/2 are all-yes; GP_HANGAR_ARSENAL is 0 of 390, and GP_READY_ROOM, GP_OPTIONS, GP_PAUSE_MENU and GP_GAMEOVER are all zero. So it is not a general standalone/composited test. GP_OPTIONS and GP_PAUSE_MENU are screens a player plainly sees as screens and declare no backdrop; read as "composited" the rule would make 92 % of the game's screens composited, which the archives do not support. What it appears to separate is narrower: screens that BEGIN FROM BLACK from everything else. A pause menu over gameplay, a hangar over a 3D scene and a plate over a title all lack a backdrop without being the same kind of thing -- the negative class is heterogeneous, which is what a two-way rule cannot express. For the port: exact within GP_TITLE, so --black for those twelve is justified from the file rather than assumed; do not carry it into the four archives they have yet to export, where in three of them it classifies every screen alike. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Wuu56cE8vJGTBtn1ppsk8v
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.