146a604500
`main_menu` -- the milestone's gate -- agrees with the reference renderer to
within 3/255 on every channel of every pixel, RMSE 0.38 %, no pixel above 4 %.
Nine of the twelve screens are at or under that; two are byte-identical.
Three exceed it, and each gets a cause rather than a wider tolerance:
* `title` (max 6): every disagreement is INSIDE A TIE -- the derived order and
the CLI's measured-off-the-game order differ only among elements with
identical layer keys. That is exactly the residual HANDOFF Q3 documents and
the export already declares in `unresolved: paint_order_ties`. Cost: 904 px at
4-6/255 in one glow band. The port keeps the stable sort; fitting it to one
screen's capture would be tuning.
* `title_jp` (max 154): `ptlogo_eff2` at 125 % is the only drawn element in the
whole export at a scale that is not a whole multiple of 100 %, and `title_jp`
is the only screen over 6/255. Same fact twice. `ui_layout::blit` samples the
source at the destination pixel's top-left corner; a GPU samples at its
centre, and at 125 % those disagree on one column in five.
I think the CLI is the one that is wrong -- corner-sampled nearest is a
half-pixel bias toward the top-left that no rasteriser produces. But that is a
reading, not a measurement: it needs a framebuffer capture of the Japanese
title screen, so it is filed in BLOCKED.md as a question. The port is NOT
changing to match, because matching would mean reproducing a half-pixel offset
on purpose to make a number smaller.
* `extras` (max 4): two pixels.
Also reconciled: the pivot question predicted a P1 diff could not distinguish
the declared pivot from half the texture, because both renderers use the
declared one. That held. Recorded so the agreement is not later mistaken for
evidence -- and P2 will not settle it either.
BLOCKED.md's `/reborn` HEAD updated to bc6354d, with a note that the mount is
read-only by design and `git -C /reborn pull` fails rather than being skipped.
2.7 KiB
Sylpheed Godot
A clean-room Godot 4 port of Project Sylpheed: Arc of Deception, starting with the menu shell: developer splash → intro video → title → main menu → submenus.
You need your own copy of the game. Nothing in this repository is game content. An offline exporter reads the disc you supply and writes an open, moddable asset tree; the Godot project reads only that tree and never touches a disc format.
your disc ──▶ crates/sylpheed-export ──▶ export/ ──▶ port/ (Godot 4)
(Rust; decoders come from JSON + PNG reads ONLY
sylpheed-formats) + OGG + OGV open formats
Why the wall
Two reasons, and the second is the interesting one:
- Godot cannot read IPFB archives, RATC bundles, T8aD textures, XMA banks or WMV video, and it should not learn to.
- Modding is a goal of this port. If the runtime reads the original formats, modding means reverse engineering. If it reads JSON and PNG, modding means opening a file.
Where the knowledge comes from
The decoders live in sylpheed-formats, pinned by revision — a
separate project, where the reverse engineering happens. Its
docs/port/HANDOFF.md is the contract: what has been decoded, what was measured
off the running game, and what is known to be undecodable. Read it before
assuming a value is on the disc.
Layout
crates/sylpheed-export/ |
disc → open formats. Regenerates export/ wholesale |
port/ |
the Godot 4 project |
authored/ |
decisions that are not on the disc, each with its reason |
export/ |
generated, gitignored, never hand-edited |
tools/ |
verification harnesses that hold the port to the reference renderer |
docs/ |
the mission, the format spec, the agent's loop prompt |
Verifying
sylpheed-cli screen render -- built from the same sylpheed-formats revision
the exporter is pinned to -- is the reference renderer. tools/verify-screen
draws every exported screen both ways and reports the largest per-channel
difference in the frame:
tools/verify-screen # every screen in the manifest
tools/verify-screen main_menu # one of them
Where the two disagree, one of them is wrong; docs/DECISIONS.md says which and
why, rather than tuning the port until the number goes down.
Status
P1. The exporter writes GP_TITLE's twelve screen builds and their sprites,
and the Godot project draws any of them statically at 1280x720 from that tree
alone. main_menu matches the reference renderer to within 3/255 on every
channel of every pixel. Next: P2, keyframe animation.