Files
Sylpheed/docs/port/DECISIONS.md
Sylpheed port agent 7a6a027fc8 port: P7 -- the new-game intro plays, and the two screens it skips are named out loud
S00A has been exported since P4; what P7 needed was something to play it and a
defined place to land. Both are here, and the interesting part is the gap.

The real chain is NEW GAME -> DIFFICULTY -> SELECT DATA -> (A) on a save slot ->
~4.5 s -> S00A. DIFFICULTY and SELECT DATA are MEASURED destinations that are not
GP_TITLE builds, so no screen file exists to go to. The port jumps from NEW GAME
to the one thing in that chain it has -- and the whole design is about not
letting that read as a sequence:

  * MenuFlow.accept returns a new kind, `video`, rather than folding this into
    `blocked`, because the caller has to announce the skip and a distinct kind is
    what forces it to;
  * the runtime prints the skipped screens by name on every run;
  * flow.json carries `skipped_chain` as DATA, so what is missing lives beside
    the decision instead of inside a GDScript string.

After the movie the port returns to the title. Authored, and it has to be: the
game goes into mission 1 and gameplay is out of scope. The ~4.5 s before the
movie is left EMPTY on purpose -- GP_TITLE does carry a loading screen and 4.5 s
is about the right shape for one, which is exactly why that belongs in BLOCKED.md
and not in flow.json.

`--script`'s 20 s per-step timeout would have killed every movie run at step 1.
Raising the constant would have been wrong the other way: a movie stuck at frame
0 would then hang the job, and a job that waits is worse than one that fails. The
test is now LIVENESS -- while get_stream_position() advances the deadline moves
with it, and a stalled movie still trips the same 20 s.

Found while looking: GP_TITLE's four unnamed builds (entries 0, 1, 12, 15) are
LOADING screens -- every element in all four is pgloading_*, and LOADING is one of
the three names the decoder read out of the title part's state function. NOT
renamed here: which member of each pair is which locale is an inference, and a
name stops being questioned once written. Handed over.

One of them is a second casualty of the rest.t problem, and a worse one:
pgloading_eff00.prm rests OPAQUE BLACK at t=38, so anything drawing that screen
at its declared rest paints a black rectangle over all of it. The title's case
only dimmed a frame.

REFUTATION, attempted and SURVIVED: HANDOFF says "exactly the six screen builds
carry the black .prm quad while the six overlays do not". Counting bundles with a
full-screen black primitive gives 8 and 4 -- build_12/15 carry one too. But
theirs runs black -> held -> clear where the transition quad runs black -> clear
-> black, so read strictly as "the quad whose group is the transition" the claim
holds. Recorded anyway: there are two kinds, and the naive census over-counts.

Gate: NEW GAME -> S00A plays 93.75 s against a declared 93.9 -> title, with
98.453 s recorded off the Master bus. What that does NOT show is that S00A's own
audio is in the mix -- bed and movie were not separated in this run, and the
write-up says so.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WM5XL4HfrHuxz8RiMWdCMC
2026-08-29 13:12:41 +00:00

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# Decisions
One entry per decision that outlives the container it was made in. Newest last.
A decision that lives only in an agent's context is lost when that container
dies, which is what this file is for.
---
## P0 — the exporter, 2026-08-28
### The exporter reads one authored file, and stamps its provenance into the output
`export/` is derived and `authored/` is hand-written, and the natural reading of
that is that the exporter never touches `authored/`. But a screen has to be
*called* something, and the disc does not name its builds — the identification of
build 5 as the main menu is HANDOFF Q2, **measured against a live capture**, not
a field.
Two ways to handle that:
1. the exporter emits `build_05.json` and the runtime renames it from
`authored/screen_names.json`;
2. the exporter reads that map and writes `main_menu.json` directly.
Chose **2**, with a condition: every name it applies carries `name_source:
"authored"` and a `name_why` quoting the evidence, and `check` **rejects** an
authored name with no `why`. The file that lands in `export/` is therefore still
honest about which of its fields is a measurement — which is the property the
derived/authored split exists to protect — while a human opening the tree sees
`main_menu.json` rather than having to resolve a rename in their head. A build
nobody has identified exports as `build_NN` with `name_source: "index"`, which is
a locator and not a claim.
This is the **only** authored input the exporter takes. Everything else in
`authored/` is applied by the runtime over `export/`.
### Sprites are per screen, not a flat pool
`main_menu` and `extras` both ship a `ptbase.t32` and they are different
pictures. A flat `sprites/` directory would have silently collided; whichever
screen exported second would have won, and the loser would have drawn the wrong
background with no error anywhere. `sprites/<subdir>/<screen>/<name>.png`.
### The format is executable
`sylpheed-export check --out export` validates a tree against `docs/FORMAT.md`
with no disc in hand. It exists because "the export is correct" is otherwise an
assertion, and because the P0 gate is *"validates against FORMAT.md"* — which is
not a thing anyone can confirm by reading.
It reads the tree the way Godot will: as a stranger, with no access to the disc,
the decoders, or the exporter's internals. It deliberately does **not** check the
export against the disc — that is what `sylpheed-cli screen render` is for, at P1.
Checked that it bites, rather than assuming: five mutations of a valid
`main_menu.json` — a broken `paint_order` permutation, a dangling
`focus_sprite`, a reversed `buttons` list, a `#rrggbbaa` colour, an invented
`name_source` — are each caught with a specific message.
### The highlight sprite pairs by name; `opt ` is exported but not believed
FORMAT v1 said `focus_sprite` came from the element's `opt ` link. That reading
was **measured and refuted** by the RE agent, and this export shows why plainly:
on the main menu, `opt ` chains `ptloop01 → ptloop02 → ptbtn01` — two decorations
and then a button. It is a linked list of something, and it is not focus.
The highlight is paired by **sprite name** instead (`ptbtn01.t32`
`ptbtn01f.t32`), which is HANDOFF's convention and holds for all 54 real pairs on
the disc. It resolves all five main-menu buttons. The raw link is still exported
as `opt_link`, renamed so that nothing downstream mistakes it for navigation, and
so that whoever eventually decodes it has the data.
Note this is 🟡 a naming convention, not a decoded field. It is authored in
effect, and lives in the exporter only because it is a rule over disc data rather
than a value we chose.
### The paint order is exported, not authored
Q3 decoded it — a `u16` layer key at `+0x0A` of each `T8aD` sprite header,
stable-sorted with declaration index. So it is read in the exporter, per the
contract's own rule for a decoded answer, and `paint_order` in `export/` is a
derived field. `"paint_order"` is gone from `unresolved`; **`paint_order_ties`
replaces it**, because the tie-break is still unknown and costs one element's
blend on one screen.
Where an element has no `T8aD` header the key comes from the decoders' table of
keys **measured off the running game**. That is a different kind of fact, so it
is labelled: `layer_source` is `"sprite"`, `"implied"` or `"none"`, and a
consumer that needs to know whether a layer is read or measured can tell.
### Colours are exported as two fields with the byte order in the name
There are two modulate colours and they multiply: `tint` is RGBA, `fade` is
**ARGB** and its high byte is the alpha that ramps. v1's single `"#ffffffff"`
could not carry both and silently discarded the ramping alpha. They are exported
as `tint_rgba` and `fade_argb`, raw hex, byte order in the key — because getting
it backwards is silent and looks like an art bug rather than a parse bug.
### `t` stays raw
HANDOFF Q1 is answered — linear ramp, 2 units per rendered frame, working
conversion 1 unit = 1/60 s — but that conversion is **measured off the running
game, not read from the file**, and the finding itself flags the 27.6 present-
frames/second measurement as the part worth re-testing. If the game turns out to
present at 60 Hz, every duration halves.
So `t` is exported exactly as the disc spells it, `keyframe_time_unit` stays in
`unresolved`, and the conversion will live in one authored place at P2. One
constant to change, in a file that says it is a decision.
### The final keyframe has no `t`, and `check` enforces that
The disc has no time slot on the last keyframe of a group. A file that carries
one there has invented it. `check` rejects it — this is the one place where the
temptation to emit a plausible number is strongest and the resulting error is
completely invisible.
---
## P1 — Godot draws the screen, 2026-08-28
### The Godot side reads the manifest, not a path
`ExportTree` is the only class that knows where `export/` is: `SYLPHEED_EXPORT`
if set, otherwise `<project>/../export`. Screens are addressed by their manifest
**name** (`main_menu`), never by a file path, so the runtime never encodes the
archive's subdirectory and a re-export that moves a file does not break it. It
also checks `format` on both the manifest and each screen, and refuses a tree it
was not built to read rather than half-drawing one.
Textures are read as bytes and decoded with `load_png_from_buffer` at runtime.
They are deliberately **not** Godot-imported resources: `export/` is gitignored
and regenerated wholesale, and a `.import` sidecar per sprite would be derived
state living next to derived state, invalidated on every re-export.
### One CanvasItem draws the whole screen
`ScreenView._draw` walks `paint_order` and draws each element itself, rather
than making a node per element and leaning on `z_index`. The export's
`paint_order` is already back-to-front, so honouring it is a loop; expressing
the same order through sixteen nodes' z-indices would hide the one thing that is
still unresolved about it — the **ties** — behind Godot's own sibling rules,
where a change in the export would silently become a change in Godot's tree
order instead of a visible change in the draw sequence.
### P1 draws `rest` and nothing else
Every element is drawn at its resting pose. No keyframe interpolation: that is
P2, and it depends on the keyframe time unit, which is **measured** rather than
decoded. A milestone whose gate is a pixel diff must not have a measured
constant inside it, or the diff stops being evidence about the port.
For the same reason `focused_id` is empty at P1. Initial focus was measured as
unstable boot to boot (HANDOFF Q5), so choosing one is an authored decision and
it belongs to P5, where a human is pressing keys.
### Nearest-neighbour, and why that is not a preference
`TEXTURE_FILTER_NEAREST`. The export is a 1:1 copy of the disc's own texels and
elements draw at up to 500 %; a bilinear filter invents detail the disc does not
have. It is also what the reference renderer does — `ui_layout::blit` maps
destination to source by integer division — so a filter difference cannot
masquerade as a placement difference in the diff.
### The capture is the SubViewport, not the window
The screen is drawn into a `SubViewport` sized to the export's own `design`
rectangle and shown through a container that scales it to the window. The first
attempt captured `get_viewport()` and got **1235×695**: there is a window manager
on the Xvfb display and its title bar had eaten 45×25 px of a screen the export
declares as 1280×720. A gate that compares a rescaled 1235×695 capture against a
1280×720 composite measures the compositor.
So `--capture` grabs the SubViewport texture: exactly the design rectangle,
independent of the window, directly comparable with `screen render` with no crop
and no resample. The windowed run is still worth doing — it is what proves a
human sees the screen — but it is not what the numbers come from.
## P1 gate — the diff, and what it found
`tools/verify-screen` renders every screen in the manifest both ways and reports
the largest per-channel difference anywhere in the frame. Both renderers are held
to the same inputs: the reference CLI built by `build-reference-cli` from the
revision the exporter is **pinned** to (not `/reborn/target/`, which is a live
mount that moves mid-iteration), `--black` because the screen carries its own
background, and `--primitives --animated` because those are what make the CLI
draw the same element set the port draws at rest.
| screen | build | max per-channel Δ | |
|---|---|---|---|
| `main_menu` | 5 | **3** | the P0/P1 gate screen |
| `main_menu_jp` | 8 | 3 | |
| `extras` / `extras_jp` | 6 / 9 | 4 / 3 | |
| `press_start` / `press_start_jp` | 2 / 3 | 1 | |
| `build_00` / `build_01` | 0 / 1 | 3 | |
| `build_10` / `build_11` | 10 / 11 | **0** | byte-identical |
| `title` | 4 | 6 | paint-order tie, below |
| `title_jp` | 7 | 154 | sampling phase, below |
`main_menu` — the milestone's own gate — agrees to **≤3/255 on every channel of
every pixel**, RMSE 0.38 %, with **no** pixel differing by more than 4 %. 3/255
is what integer-truncating compositing in the CLI and float rounding on a GPU
differ by; there is no structural disagreement anywhere in the frame.
Three screens exceed that, and each has a named cause rather than a threshold.
### `title`: a tie in the paint order — neither renderer is wrong
Build 4 is the one screen where the CLI uses a paint order **measured off the
running game** instead of deriving it. Compared against the order this port
exports, every single disagreement is **inside a tie** — the two orders differ
only among elements carrying *identical* layer keys (`0x8083`, the `back2` glow
group, and `0x80a0`):
```
derived : … 15, 16, 17, 18, 0, 1, 2, 3, 4, 5, 7, …
measured: … 15, 18, 16, 17, 0, 2, 4, 7, 1, 3, 5, …
```
That is exactly the residual HANDOFF Q3 documents and this export already
declares in `unresolved: ["paint_order_ties"]`. It is worth stating what it
costs: **904 px** in the glow band at (445,117)(1195,313), all of them 46/255.
The port keeps the stable sort, per HANDOFF's own recommendation. Nothing to fix,
and nothing to tune — a "fix" here would be fitting the port to one screen's
capture.
Two of the reordered indices (`0x80a0`) are `kind & 0x4` template instances that
both renderers skip, so the only real reorder outside the glow group is
`ptlogo2` against `ptlogo_tm`, which do not overlap.
### `title_jp`: nearest-neighbour sampling phase — the CLI is the one I would call wrong
`title_jp` is the **only** screen in the export with a drawn element at a scale
that is not a whole multiple of 100 %: `ptlogo_eff2` at 125 %. It is also the
only screen with a difference above 6/255. The two facts are the same fact.
At a non-integer ratio the two renderers pick different source texels:
* `ui_layout::blit` samples the source at the destination pixel's **top-left
corner** — `sxi = col * sw / dw`.
* A GPU samples at the destination pixel's **centre** — `floor((col+0.5)·sw/dw)`.
At 125 % those disagree on one column in five, which is why the differing pixels
are ~30 above 100/255 strung along thin diagonal edges rather than a shifted
region. At every whole multiple of 100 % they agree exactly, which is why the
other eleven screens are clean.
**Which is wrong:** the CLI, I think. Corner-sampled nearest is a half-
destination-pixel bias toward the top-left that no rasteriser produces, and the
Xenon GPU that drew this screen sampled at pixel centres. But I have no
framebuffer capture of `title_jp` and the disagreement is sub-pixel on one glow,
so this is a reading, not a measurement — recorded in `docs/BLOCKED.md` rather
than acted on. **The port is not changing to match**, because matching the CLI
here would mean deliberately reproducing a half-pixel offset in order to make a
number smaller.
### `extras`: two pixels
Two pixels at 4/255. Rounding.
### What the diff cannot tell us
The pivot question in `docs/BLOCKED.md` predicted that a P1 diff could not
distinguish "anchor scale to the declared pivot" from "anchor to half the
texture", because both renderers use the declared pivot. That prediction held:
the port and the CLI agree on every scaled element, and that agreement is **not
evidence** about which anchor the game uses. It stays open.
### ~~`pteff05.t32` and `pteff04.t32` have no sprite, and that is correct~~
**RETRACTED 2026-08-29. This was wrong, and it was the most consequential thing
on this page.** See "The menu had no background" below.
---
## P2 — keyframe animation, 2026-08-28
### The time unit is authored, in one file, and says loudly that it is not on the disc
`authored/timing.json`. HANDOFF Q1 is answered — linear ramp, 2 units per
rendered frame, 1 unit = 1/60 s — but that conversion is **measured off the
running game**, not read from a file, which is exactly the case the
derived/authored split exists for. It is expressed as
`keyframe_units_per_second: 60` rather than seconds-per-unit so the value is
exact instead of a repeating decimal, and it carries the two independent lines
that support it. `t` stays raw everywhere in `export/`; seconds appear only
where this file is applied, which is one line of `boot.gd`.
`exit_ramp_seconds` is deliberately **null**. See below.
### The timeline stops at the last *timed* keyframe, and never plays the exit
The last keyframe of every group carries **no `t`** — the disc has no time slot
there. Across this export that final frame is an *exit* pose: for 116 of 134
elements it differs from the last timed keyframe **in alpha only** (a fade-out),
for 12 it is the loading splash's scale-and-slide exit, and for 6 it is
identical (no exit animation at all).
So the group is `pre-roll → ramp in → hold → [exit]`, and the port plays it up to
the hold and stops. Playing into the exit would mean **inventing how long the
ramp takes**, because the disc does not say. That duration is the screen
transition — HANDOFF Q7 measured it at ~0.4 s — and it belongs to P3, with its
own evidence. This is why `exit_ramp_seconds` is null rather than 0.4: P2 has no
business holding it.
### The interpolation is checked by where it lands, not by inspection
For **8 of the 12** screens the settled timeline is **byte-identical** to the
`--pose=rest` render. That is the useful assertion: the port walks the keyframes
with an authored time unit and arrives, to the pixel, at the pose the pinned
decoders independently identify as the resting one. `tools/screen-strip` reports
this per screen, so a change to the interpolation that drifts by one unit shows
up as a diff rather than as nothing.
The four that differ do so for two distinct reasons, below.
## `rest` misidentifies six elements, and the running game says so
On `main_menu`, the settled timeline and `rest` differ in exactly one region:
**400×470 at (440,108)** — the bounding box of `ptframe1` and `ptframe2`, and
nothing else on the screen.
`rest` puts both at their **first** keyframe: off-position and fully
transparent. The keyframes say they slide (620,108)→(440,108) and (403,267)→
(583,267) while fading 0x00→0xff, and then hold that pose for their last three
keyframes including the untimed one.
`/reborn/docs/re/captures/main-menu-oracle.png`, a capture of the running game,
**shows them**: the bright circuit-frame bracket around the menu, with a ring at
the bottom right. Cropping the same 250×180 region from the capture and from
both renders puts the ring and its elbow trace in the port's timeline render
**pixel-aligned with the game's**, and absent from the `rest` render. That is
geometry, not luminance, so it does not depend on the capture's gamma or on the
fact that it was taken with `NEW GAME` focused.
### Why the decoders get it wrong, precisely
`ui_layout::rest_plateau` excludes a run of identical keyframes that **ends the
group**, because that run is normally the exit — the comment cites the pause
menu, where taking the trailing run erased the word PAUSE. That exclusion is
right in general and wrong for an element with **no exit animation**, where the
trailing run *is* the hold. The rule then falls back to an earlier run, which
for a slide-in is the invisible pre-roll.
The condition that identifies the affected elements exactly, with no false
positives in this export, is:
> the final untimed keyframe has the **same pose** as the last timed keyframe
Six elements match it and `rest` misses all six: `ptframe1`/`ptframe2` on
`main_menu` and `main_menu_jp`, and `pteff02` on `title` and `title_jp`. This is
a **finding for the RE agent** about `sylpheed-formats`, not something this port
fixes: the decoders are pinned and must not be reimplemented here. The port
simply does not use `rest` — it derives the arrived pose from the keyframes,
which needs no heuristic — and `verify-screen` still asks for `--pose=rest` so
that renderer-vs-renderer diffing compares like with like.
Note what this says about P1: the port and the reference renderer **agreed** on
`main_menu` to 3/255, and both were missing two elements the game draws. Two
renderers reading the same field through the same decoder agreeing is not
evidence that the field is right. `docs/BLOCKED.md` had already said that about
the pivot; here it bit for real.
## The title is not settled, and P2 does not claim it
`title` and `title_jp` differ between the two modes by much more (max 142 and
247), and there the disagreement is **not** the six-element bug alone. `rest`
picks a mid-timeline hold for several glows (`pteff01`, `ptlogoall_eff`,
`ptlogoall_eff2`, `ptlogo_back2eff5`) where the timeline runs on to a much
brighter pose.
I could not settle which is right, and did not try to make the numbers agree:
* No element's alpha ever reverses direction anywhere in this export, so the
title's 4.48 s timeline is a slow one-way ramp, not a pulse — which removes the
obvious reason to expect a loop, but does not prove there is none.
* The only live title capture composites the **`PRESS Ⓐ` plate (build 2) over
the title (build 4)**, so it cannot be diffed against build 4 alone. Mean
luminance is oracle 64.1, `rest` 62.8, timeline 80.0 — which looks like it
favours `rest`, except that the plate *adds* brightness and `rest` is carrying
a 25 % black dim quad (`pteff02`) that is itself one of the six misidentified
elements. The comparison is confounded in both directions and settles nothing.
* **Both modes are visibly wrong anyway.** Side by side with the capture, the
port draws a washed-out cyan glow slab across the logo that the running game
does not have — in `rest` mode too. That is a third problem, independent of
this one, and it is P3's.
So: the timeline is the default because it is derived from the disc's own
keyframes with one measured constant and no heuristic, and because it is proven
right on the screen this milestone gates. On the title it is **unverified**, and
P3 should not assume P2 settled it.
---
## P2, corrected — the pin moved, and the settle rule was wrong, 2026-08-28
### Answering the RE agent's question: which six, and on what screens
They asked, having found only two elements on the English main menu satisfying
the condition this port proposed. The six span the whole 12-screen export:
| element | screens | trailing run |
|---|---|---|
| `ptframe1`, `ptframe2` | `main_menu`, `main_menu_jp` | alpha `0xff`**visible** |
| `pteff02` | `title`, `title_jp` | alpha `0x00`**transparent** |
So four of the six are the pair they already found, once per language build, and
their alpha rule accepts exactly those. The other two are `pteff02`, whose
trailing run is transparent, so their rule **excludes** it and leaves `rest` at
`0x40`.
**That exclusion is right, and their own measurement proves it.** `pteff02` is
the 25 % dim quad; they measured the title render going from **+13.14 to +0.55**
against the plate-free capture once the dim is drawn. `rest` must therefore stay
at `0x40` and must *not* move to the transparent trailing run — which is what
their rule does. Two investigations converging from opposite directions.
The condition this port proposed was **too loose**; the alpha discriminator is
the correct rule and the port has no amendment to offer.
### The pin moved 8b6dbcf → 5414db3
Its own commit, and what I wanted from it is the fixed `ui_layout::rest()`.
Pinned at `5414db3` rather than `4bc9706` where the fix was written, because
`5414db3` is where it carries its disc-wide check — 30 of 13 991 elements move,
4 become visible, **0 become invisible**.
The re-export is the evidence the change was contained: **two files changed, and
within them exactly four `rest` blocks** — `ptframe1`/`ptframe2` on both main
menus moving from `(620,108)/(403,267)` at `t=16` and alpha `0x00` to
`(440,108)/(583,267)` at `t=62` and alpha `0xff`. Every diff line pairs; the
other ten screens are byte-identical, `pteff02` did not move, and no sprite
changed.
### The settle rule was wrong, and their title finding is what showed it
P2 shipped "hold the last **timed** keyframe", on the reasoning that the exit is
the final untimed frame. **That is wrong**, and the title is the counter-example:
`pteff02` holds at `t=46` with the dim at alpha `0x40` and then ramps to `0x00`
by `t=236`. The exit is not only the untimed frame — it can be a long run of
timed ones. Running to the end drops the dim and makes the whole screen ~13/255
too bright, which is exactly the luminance excess P2 recorded (oracle 64.1,
`rest` 62.8, timeline 80.0) and could not explain.
A group is `pre-roll → ramp in → hold → ramp out → post-roll`, and a screen that
has arrived sits on **the hold**. So the timeline now plays in and stops at
`rest`, which is the decoders' identification of that hold and carries its own
`t`. `settle_units()` is `rest.t`.
The check is that the disagreement vanishes: on **all twelve** screens the
settled timeline is now byte-identical to the `--pose=rest` render, where before
this change four of them differed by up to 247/255. The timeline's endpoint
*should* be `rest` — the animation is what the timeline adds, not a different
destination — so this is the property to want, and it now holds without a
special case.
That also retires P2's open question about looping, from the other side: the RE
agent measured that groups hold rather than loop (`ptloop01`/`ptloop02` park
off-screen at x=1521 and x=839; 18 s of settled title sits at sd ≤ 0.01).
## The reference renderer was stale for three diff runs
Worth recording as a process failure, because it defeated the project's whole
verification method for a while and it failed *silently*.
After bumping the pin I rebuilt the reference CLI, and `build-reference-cli`
reported success at rev `5414db3`. `verify-screen` then showed `main_menu`
jumping from 3/255 to **72/255**. The natural reading — the port had regressed —
was wrong. The port was right and **the reference was a revision behind**: the
shared `CARGO_TARGET_DIR` still held a `sylpheed-cli` built from `8b6dbcf`, and
cargo reported `Finished in 0.13s` and left it in place. Building into a clean
target directory produced a binary that resolves `ptframe1` to `(440,108) t=62`;
the shared one still said `(620,108) t=16`.
The old check — "does `screen list` run?" — cannot catch this, because a stale
binary runs perfectly.
Two changes:
* `build-reference-cli` builds into `$CARGO_TARGET_DIR/reference-cli/$rev`, a
tree **keyed by the pinned revision**, so a new pin has no artifacts to reuse.
A stable copy is placed alongside for consumers.
* It then checks the binary **against `export/`**: both come from the same pin,
so if the CLI resolves `ptframe1`'s rest differently from what the exporter
wrote, the two halves of the verification are not the same revision and it
fails loudly. It compares the two rather than asserting a literal, so it stays
true when the pin moves again.
`docker/bin/` is baked into the image, so this takes effect on the next image
build; until then the repo copy has to be invoked by path. The RE agent hit the
same class of trap this session from the other side (`./target/debug` stale
against a redirected `CARGO_TARGET_DIR`). It is worth naming the general shape:
**a build system reporting success is not evidence that the artifact you are
about to trust is the code you pinned.**
### What this did not change
`title` (6/255), `extras` (4/255) and `title_jp` (154/255) are unchanged, and
their diagnoses stand — a paint-order tie, two pixels, and nearest-neighbour
sampling phase at 125 % scale. The title's swoosh defect the RE agent localised
(drawn thick and white where the game draws it thin and pink) is untouched by
any of this and remains P3's.
---
## The menu had no background, and P1 called that correct, 2026-08-29
The pin moved `5414db3 → f817dd5` for `56cc7ac`, "a RATC child's name is stated,
not inferred". `ratc::parse` had named each child by scanning backwards for the
last printable run of bytes before its magic. For `pteff05.t32` the three
trailing payload bytes are `38 41 58``8AX` — which beat the real name, so the
child registered under a name no element declares and resolved to no sprite.
`pteff05.t32` is the **full-resolution background of all five menu screens**.
So every render this port has produced of a menu screen has been missing its
background, and P1 wrote that up as a property of the disc: *"the bundle declares
them and carries zero RATC children for either, so there is no texture on the
disc to export."* That sentence was false. The bundle carries the child; the
decoder was handing back the wrong name for it. Retracted above rather than
edited away.
### What the re-export shows
Six new sprites and nothing else: `pteff05.png` on `main_menu`, `extras` and
their Japanese twins, `pteff04.png` on both titles. Per screen the JSON gains a
`sprite` line and `layer_source` moves `"implied" → "sprite"` — the layer key is
now **read from the file** instead of taken from the decoders' table of keys
measured off the running game. That is the derived/authored ratchet turning the
right way, in the exporter rather than in `authored/`.
`pteff05.png` is **1280×720**; `ptbase.png`, which had been carrying the
background alone, is 640×360 drawn at 200 %. The screen was being shown its own
art at half resolution.
### Measured against the live capture, not against the other renderer
Whole-frame RMSE of the settled `main_menu` against
`captures/main-menu-oracle.png`:
| | RMSE |
|---|---|
| before this pin | 8.05 % |
| with the real background | **5.92 %** |
A 26 % reduction, and it is the right kind of evidence: the reference renderer
was missing the same element for the same reason, so a renderer-vs-renderer diff
could not have found this. It is the third time on this project that the
capture caught something both renderers agreed on — the bracket, the title dim
quad, and now the background.
`verify-screen` after the bump is unchanged in character: everything at 34/255
except `title` (6, the paint-order tie) and `title_jp` (155, the sampling phase).
Both renderers gained the background together.
### One thing the comparison says that I did not expect
Rendering with `--focus=ptbtn01`, which is how the capture was taken, makes the
RMSE **worse** — 5.92 % → 7.00 %. The port *replaces* an element's sprite with
its `*f` twin; `sylpheed-cli`'s own `--focus` is documented as drawing the
focused record **over** the base element. Those are different operations, and
the capture shows a ring marker beside `NEW GAME` that the port does not draw.
This is P5's, not P2's, and it is not being guessed at here. Raised in
`docs/BLOCKED.md`.
---
## P3 — splash → title, unattended, 2026-08-29
### The splash is located by entry index, because no rule can find it
The RE agent looked for a content predicate and there is none: design size fails
(every extra composable bundle sampled is 1280×720, the same as every screen) and
element count fails (fragments run 2…15 elements in `GP_OPTIONS`/`GP_SAVE_LOAD`
while the splash halves are 3 and 7 — the ranges overlap).
So `screen_builds` is now `is_build` **plus an authored allow-list of entry
indices**, in `authored/screen_names.json` under `also_export`, each with a `why`
that says it is a locator and not a claim. This is safe in `GP_TITLE` and would
not be in general: there, widening adds exactly four bundles and all four are
real screens with zero fragments. That is why it is an allow-list rather than a
loosened predicate.
**There were two splash screens and the port had neither.** Entries 11/14 are the
developer logos (GAME ARTS / SETA / studio anima); entries **10/13 are the SQUARE
ENIX publisher wordmark, the first thing the boot shows**, and nothing in this
project had noticed them. Both pairs are region twins — ™ on 10, ® on 13 — and
the port shows one of each, not both.
### `authored/screen_names.json` is now keyed by pak entry, not by ordinal
Widening the enumeration renumbers the ordinals, and a name that moves when the
enumeration rule changes is not a name. The file had always called the entry
"the stronger locator"; it is now the only stable one. In `GP_TITLE` the two
coincide across all 16 entries, which is also the numbering `sylpheed-cli screen
--build N --all` takes — so `verify-screen` now passes `--all`, and without it
`--build 10` would have landed on entry 12.
The two previously-unnamed plates therefore renamed `build_10`/`build_11`
`build_12`/`build_15`. Their names were always locators; now they locate the
right thing.
### The exit is the group playing itself out, not a black rect over a freeze
HANDOFF's answer to ask 2 was (a), and it came with a test that discriminates
rather than a plausibility argument. Under "a black quad over a frozen screen"
every region is scaled by the same 1α, so the button-region / background-region
brightness **ratio** stays constant through the fade. Measured, it falls
6.495 → 5.574 → 3.105 → 2.125 → 1.935 — a 3.4× monotonic drop. The screen plays
out: `pteff00.prm` ramps to opaque black while the labels, `ptmsg`, `pteff10`
and `pteff12` ramp to transparent, and `ptframe1`/`ptframe2` hold.
Implemented by giving the final untimed keyframe a **synthetic time**,
`exit_ramp_units` after the last timed one, and then interpolating it like any
other. One code path: the difference between arriving and leaving is only how far
`t` is allowed to run, not a second kind of animation.
`exit_ramp_units = 24` (~0.4 s) is authored, and `authored/timing.json` carries
the RE agent's own reach caveat rather than smoothing it: the filmstrip is
downsampled and the button region contains some background, so this pins the
**direction**, not 0.4 s to ±0.05 s, and it is one transition pair.
### Nothing waits on a timer the disc does not carry
`dwell` in `authored/flow.json` is deliberately empty. Each screen's dwell is its
own keyframe group — the publisher wordmark reaches its hold at t=235 (3.92 s),
the developer logos at t=190 (3.17 s), both read from the disc. Adding a hold on
top would be inventing a number nobody measured. The pacing you see is the
disc's own, and the file says where a measured number would go.
### The last screen holds
A screen plays itself out because something is taking its place. Nothing takes
the title's place yet, so the sequencer holds there. A boot that ends by fading
to black is a boot that looks like it crashed. P4 puts the intro video in front
of the title and P5 gives the title somewhere to go.
### `flow.json` reproduces an observation and says so
Q6 closed with a negative: the order is in none of the four places it could have
been, and a transition is a call with a name argument chosen by code. So this
file is authored and its header says plainly that it reproduces what was watched,
not what any file states. The intro video's place in the real boot is **named as
a gap** rather than the order being quietly rewritten to hide it.
## P3 gate
`godot --path port -- --boot --film=/tmp/boot` runs unattended:
```
publisher_logo → developer_logos at 4.65 s → title at 8.57 s
boot sequence complete after 13.05 s, holding on title
```
The filmstrip shows each screen fading in, holding, and fading through black into
the next, and the title staying up. `verify-screen` covers all **16** screens
now; the four new splash bundles come in at max 12/255 against the reference
renderer. The three known differences are unchanged: `title` 6 (paint-order tie),
`main_menu` 4, `title_jp` 155 (sampling phase at 125 % scale).
## Answers taken from the RE agent without re-deriving them
* **Focus stays "replace".** Over-vs-instead is unobservable: the focused sprite
covers the base at 100 % of base-visible pixels, and the two compositions
differ by RMSE 1.1 inside the button rect — under the gamma floor. The port's
guess was right for the wrong reason, and the actual gap is that
`ptbtn0Nf.rat` declares **two** sprites — `ptbtneff01.t32`, a glowing ring, and
then the bright label — where `ptbtn0N.rat` declares one. The ring is P5's, and
its placement inside the record is **not decoded**, so it will be authored from
the capture and marked as such.
* **RMSE against captures has a floor, so stop chasing it.** The capture is
`≈ 255·(render/255)^γ` with γ ≈ 1.49 on the menu and `EXTRAS`, 1.34 on the
title, and it is a ramp *the game installed* (`VdGetCurrentDisplayGamma` at
video init), not a capture-path artefact to subtract. Its reach is narrow —
the flat patches it was fitted on are almost all dark — so the port will not
extrapolate it across the range, and will not apply it to rendered output on
this evidence. It is a comparison constant, not a rendering one.
* **Rotation is escalated to a human and the port has not acted.** The RE half is
answered — rotate about the **declared pivot**, measured against the GPU
capture — and it has zero effect on the five screens at rest. The port will
carry `rotation_deg` in a future FORMAT v3 because carrying a decoded field the
renderer ignores beats dropping it, but it will not draw it until the
divergence question is settled.
---
## P4 — the intro video, 2026-08-29
### Theora at 720p is fine here, and no runtime dependency is requested
MISSION §6 anticipated that Theora might be too poor at 720p and permitted the
FFmpeg-GDExtension fallback to be **proposed**. It is not needed, and this was
measured rather than judged by eye alone. SSIM against the decoded source over a
10 s sample: **0.9863 at `-q:v 6`, 0.9896 at 8, 0.9924 at 10**. At 200 % zoom on
the reel's hardest case — fine serif text and soft gradients over near-black,
where Theora breaks first — q8 is indistinguishable from the source.
`-q:v 8`, and **no GDExtension is being proposed or adopted**.
`-ac 2` because the source is **6-channel** WMA Pro and Godot's Theora path is
not a surround one. That downmix is a decision, so it lives in the recorded
command where a modder can see and change it rather than in prose.
### The exact command is in the manifest, per MISSION §6
`export/manifest.json` gains a `videos` array, each entry carrying the verbatim
`ffmpeg` line that produced it. A modder who dislikes the quality re-runs one
line instead of reverse-engineering what was done to their video — which is the
whole reason this project converts the disc rather than reading it at runtime.
### A cache, and why that is not a hand-edit
`export/` is regenerated wholesale, but re-encoding 232 s of video on every run
costs ~4 minutes to produce a byte-identical file, and an exporter nobody re-runs
is worse than a cache. So each movie gets a `.cmd` sidecar recording the command
and the source size, and the encode is skipped only when both match exactly. Any
change to either re-encodes. This is derived state validating derived state, not
a hand-edit.
### The player renders into the design viewport, not beside it
First attempt parented the `VideoStreamPlayer` to the Boot node. It played, and
every captured frame was **black**: the capture reads the SubViewport, and the
player was rendering to the window. Worth stating as more than a capture bug —
everything this port draws composes in the export's own 1280×720 design space,
and a movie outside that space is outside the coordinate system every screen is
expressed in.
### Ⓐ skips, because Q9 measured it
The only input the port handles so far. HANDOFF Q9: one Ⓐ press skips a movie,
measured — the title was reached at 57 s against a 193 s baseline. Menu
navigation is still P5.
## P4 gate
`godot --path port -- --boot --film=…` runs
`publisher_logo → developer_logos → ADV.ogv → title`, unattended. The filmstrip
shows the SQUARE ENIX ident, then the reel's live-action-styled CG, then the
title. The movie's place in the boot is **measured, not decoded** — Q9 decodes
`ADVERTISE_MOVIE → ADV.wmv` from the movie manifest, but *where it sits in the
boot order* is what the RE agent watched, and `authored/flow.json` says so.
### What I cannot verify from here
**Audible playback.** This container has no audio device — Godot falls back to
the dummy driver. What is verified is that the Vorbis stream exists in the
transcode, is 2-channel, and decodes. Whether Godot emits it audibly is
unconfirmed and is stated as unconfirmed rather than assumed from the stream's
presence. It is a cheap check for anyone with a sound device and an impossible
one here.
---
## RETRACTION — `sylpheed-cli` is not the oracle, 2026-08-29
**This corrects a framing that runs through everything above, so it is a
retraction rather than an edit.** Every place this file called
`sylpheed-cli screen render` *"the reference renderer"* — and it does so
repeatedly, starting at P1 — overstated what it is.
The correction comes from the human, via the RE agent, in their words: Reborn
"was/is just a GUI explorer and extraction CLI for verifying the decoding of the
various files. It may very well be wrong." **The oracle is the Xenia Canary
capture and the game.**
So `tools/verify-screen` is a **consistency check between two decoders that
share their assumptions**, and a regression detector. It is not a correctness
check, and agreement in it is not evidence of correctness.
### The embarrassing part is that this file already knew
After the `ptframe1` case, P2's write-up says: *"Two renderers reading one field
through one decoder agreeing is not evidence that the field is right."* Then P1's
numbers kept being quoted as though 3/255 against `sylpheed-cli` meant the port
was right. Having the principle written down did not stop me leaning on the
agreement — which is worth recording, because that is the failure mode, not
ignorance of the principle.
**Three times** both renderers agreed and both were wrong, all three caught by a
capture and catchable by nothing else:
| | what both got wrong | how it surfaced |
|---|---|---|
| `pteff05` | the menu screens had **no background** | the RE agent decoded the RATC child name |
| scale 0 | drawn at full size instead of collapsed | RE agent's control run |
| `rest()` | `ptframe1`/`ptframe2` invisible; the menu bracket missing | `main-menu-oracle.png` |
### What changes
* `tools/verify-screen` says all of this in its own header, calls the CLI the
**comparison** renderer, and a `DIFFERS` row now means "we moved apart, find
out which of us moved" rather than "the port is wrong".
* The correctness question moves to the captures. The RE agent has committed
nine of them with an index at `docs/re/captures/ORACLE-CAPTURES.md`, covering
all five screens in scope — including a **main menu with `OPTIONS` focused**,
whose difference from the unfocused menu isolates exactly what focus changes.
* Three cautions travel with any capture comparison, and they are the RE agent's:
the captures are **not gamma-neutral** (γ ≈ 1.49 menu, 1.34 title — there is a
floor, do not chase it); **geometry is sound** (best alignment 0,0 at corr
0.9466, so a positional disagreement is real); and each is **one moment of a
still-animating screen**, so compare settled poses or regions known to be at
rest.
### What does not change
The port keeps running `verify-screen` over all 16 screens every iteration. A
consistency check is still worth having — it is total, it is cheap, and it is
what catches a divergence the RE agent introduces on their side. It is simply
not a grade, and this file will stop quoting it as one.
## P5 groundwork — the focus record, checked against a capture, 2026-08-29
P5 is the lowest unfinished milestone (P0P4 are gated above). This iteration did
not implement navigation; it did the measurement P5 needs first, because the one
thing P5 is built on — how a focused button is drawn — had three claims attached
to it and none of them had been checked from this side.
### The exporter already emits the focus record's second element
HANDOFF ask 3 answers with a 🔴: *"what you are actually missing is the focus
record's SECOND element"* — `ptbtneff01.t32`, a 42×46 glowing ring, declared
before the bright label in `ptbtn0Nf.rat`.
**That gap is in the renderer, not the exporter.** `export/screens/title/main_menu.json`
already carries both, in declaration order, under `focus.elements`, for all five
buttons — `ptbtneff01` then `ptbtn0Nf`, each with its own pivot, rest pose and
keyframes. Nothing needs to change in `crates/sylpheed-export` for the ring. What
is missing is that `screen_view.gd` draws only one sprite per focused button.
Recording this so P5 does not re-open the exporter looking for it.
The ring's size checks out exactly: `ptbtneff01.png` is **42×46**, as stated.
### The `(7,7)` focus offset survives a refutation attempt, uniquely
Ask 3 states the focused sprite covers the base at 100.0 % of base-visible pixels
"once aligned properly (the true offset is **(7,7)**, and at the centre alignment
it reads a misleading 7884 %)". P5 builds directly on this, so it was worth
attacking.
Re-ran the RE agent's own metric on the exported PNGs — over every pixel where the
base sprite is visible, the fraction where the focus sprite's alpha ≥ the base's —
scanning the whole offset space, not just the stated answer:
| alignment | ptbtn01 | ptbtn02 | ptbtn03 | ptbtn04 | ptbtn05 |
|---|---|---|---|---|---|
| **(7,7)** | **100.00 %** | **100.00 %** | **100.00 %** | **100.00 %** | **100.00 %** |
| geometric centre | 80.58 % | 79.20 % | 79.58 % | 79.45 % | 79.45 % |
| pivot-to-pivot | 80.58 % | 86.59 % | 87.40 % | 79.45 % | 84.58 % |
**The refutation fails, and more strongly than the original claim.** Over a
15×14 offset scan, `(7,7)` is a *unique isolated cell* at 100 % on every one of
the five buttons — every neighbouring offset, including (6,6) and (7,6), falls
below 90 %. The centre and pivot alignments reproduce the 7884 % band the RE
agent reported as misleading. A claim that survives a search of its whole
parameter space is worth more than one checked at a single point, so this is
recorded as strengthened, not merely unrefuted.
### `(7,7)` is not a constant to apply — it is what the declared positions already say
An earlier version of this analysis had the port disagreeing with the capture by
6 px. **That was my arithmetic error and it is worth writing down**, because it is
the mistake this format invites: I computed each element's top-left as
`pos - pivot`, which gives base→focus deltas of (13,13) and a 29 % coverage — a
confident wrong number.
`pos` **is** the top-left. `screen_view.gd:121` is
`Rect2(pos - pivot*(s - 1), natural*s)`: the pivot is the anchor scale grows
about and it *cancels at 100 %*, which is exactly the "can be got wrong
invisibly" the comment there warns about. Getting it wrong invisibly is what
happened.
With `pos` as the top-left, base focus is `(542,162) - (535,155)` = **(7,7)**
directly, on four of the five buttons. So P5 draws each focus element at its own
declared `pos` and needs no offset constant at all. Nothing to author.
### The one real find: `ptbtn04` is 1 px off the grid on the disc
The focus records sit on a clean 80 px pitch — 155, 235, 315, 395, 475. The
**base** records do not: 162, 242, 322, **401**, 482, i.e. spacings 80, 80, **79**,
**81**. So `ptbtn04`'s declared base→focus delta is **(7,6)**, while the art
itself aligns at (7,7) — the coverage scan puts `ptbtn04` at 100 % on (7,7) and
below 90 % on (7,6), the same as every other button.
This is 1 px of authoring jitter on the disc, not a decode error, and it has one
consequence worth stating: **do not derive the focus placement from the base by a
constant.** Draw the focus record at its own declared `pos`. A port that
"simplified" this to base + (7,7) would put `ptbtn04`'s focus art 1 px off, and
would look right on the other four.
### Verified against a capture, not against our other renderer
Diffing two oracle frames isolates what focus changes without any instrument in
the path: `live-main-menu.png` vs `live-main-menu-options-focused.png` differ in
one tight cluster of 6 338 px at **x 506..702, y 398..445**. `ptbtn04` is the
`OPTIONS` button, and the union of its focus record under the `pos`-as-top-left
reading — ring `ptbtneff01` at (500,396) 42×46 plus label `ptbtn04f` at (535,395)
172×56 — is **x 500..706, y 395..451**. Those agree on all four edges to within a
few px of near-transparent sprite border.
Under the `pos - pivot` reading the same record predicts x 433..604, y 367..422,
which matches nothing in the capture — and *no* button matches that cluster. The
capture, not our renderer, is what settles it.
### An instrument that failed its own control, and was therefore discarded
To locate the buttons independently I wrote a masked normalised-cross-correlation
template matcher and ran it as PROTOCOL requires — **through a control first**:
match each *base* sprite against the *plain* capture, where the declared position
is known and the answer must be a (0,0) delta.
It returned deltas of (13,5), (6,19), (12,21), (16,22), (6,8) at NCC
**0.0960.206** — noise, with three of five pinned to the ±22 search boundary.
The control fails, so the instrument is dead rather than tuneable, and **none of
its output is used above.** The button art is dark, low-contrast and further
crushed by the capture's γ ≈ 1.49 ramp, which is the likely cause; a matcher for
this corpus would have to work on gradients rather than luminance. Filed so the
next iteration does not rebuild the same broken tool.
### What P5 still needs, and has not got
* **Initial focus is not stable across boots** (Q5: 2× `TUTORIAL`, 2× `NEW GAME`).
That is a value to author, with a `why` naming Q5 — it is not written yet.
* **The ring's own animation is unread.** `ptbtneff01`'s two keyframes go
`rotation_deg` 0 → **360** at t=120 with no second timed keyframe, i.e. a full
turn. Whether it spins continuously while focused, or turns once and holds, is
the group-loop question again — answered "groups hold" for build-in animations,
but a 360° hold and a 0° hold are the same pose, so *this* group cannot be told
apart by its rest pose. Not guessed; raised below.
---
## P5 — navigation, 2026-08-29
The gate is *"a human clicks through it"*, and the artifact is a walk that
proves the wiring rather than the intent: `up` (which wraps 01→05), five `down`,
Ⓐ into `EXTRAS`, `down`, Ⓑ back — landing on the main menu with focus restored
to `EXTRAS`.
```sh
xvfb-run -a godot --path port -- --menu \
--script=up,down,down,down,down,down,accept,down,cancel --shots=/tmp/p5
```
Ten PNGs, one per step, each taken after the screen it produced had settled.
Contact sheet handed over as `share` id `1788002507-ef4468a0a33a`.
### The scripted walk goes through the input system, not around it
`--script` posts `InputEventAction` through `Input.parse_input_event` and lets
it arrive at `_unhandled_input` exactly as a d-pad's press would. Calling
`MenuFlow.move()`/`accept()`/`cancel()` directly would have been shorter and
would have proved nothing: the thing most likely to be broken is the wiring
between a press and the cursor, and a direct call is precisely the part that
skips it. The same reasoning says the settle wait must be real — a shot taken
before the screen stops moving photographs a fade and calls it a menu.
### What is authored here, and what is derived
Split deliberately, because P5 is where the two are easiest to blur:
| | where | why |
|---|---|---|
| the ORDER of the items | **derived** — each screen file's `buttons`, filled by the exporter from the button-role elements sorted by resting Y | it is on the disc |
| where an item goes | **authored**`authored/flow.json` | HANDOFF Q4 *measured* the destinations; they are not in the file |
| which item opens focused | **authored** | Q5 measured that it is **not stable boot to boot** |
| what Ⓑ does | **authored** | Q5, measured — except on the main menu, see below |
| ⬅➡ do nothing | **authored**, written as an explicit no-op | so that *"the game ignores it"* and *"we never wired it"* are different lines of code |
Four of the five main-menu destinations are `goto: null` with a `blocked` note.
That is **not** an unknown: `DIFFICULTY`, the save-slot list, the lesson list and
the settings menu were all measured, and they live in archives this export does
not carry. `blocked` and `none` are kept apart so a later reader does not
"discover" a gap that was a milestone boundary.
`EXTRAS` is the only main-menu destination inside `GP_TITLE`, and therefore the
only Ⓐ-into-a-submenu this gate can actually walk.
### The one navigation rule with nothing behind it
Ⓑ on the **main menu** → title. HANDOFF Q5 states it, and `flow.json` marks it
*authored — likely but UNPROVEN*, because the title also self-returns after
~810 s idle and a single unrecorded observation cannot separate the two. The
port implements it anyway — a menu with no way out is worse than a menu with a
plausible one — and says in the file that it did. Asked of the Decoder this
iteration; see `BLOCKED.md`.
Independent corroboration that the main menu is different from its submenu:
the main menu's footer advertises only `Ⓐ : OK`, while `EXTRAS`' footer
advertises `Ⓑ : Back`. That is on the disc, in `ptmsg.png` vs `ptmsg2.png`, and
it is visible in both the port's render and the captures.
### A press during a fade is dropped
**Authored, and not measured.** Nobody has watched what the game does with a
button pressed mid-transition. Dropping invents less than queueing does: it
cannot manufacture a press the game might have discarded. `flow.json` says so
under `navigation.input_during_transition`.
---
## `--headless` cannot draw, and the port hung instead of saying so, 2026-08-29
`docs/port/PORT-MISSION.md` and the loop prompt both name `godot-headless` as
how this project runs unattended. It does not work, and the way it failed was
the worst available shape.
**Measured, not assumed.** Under `--headless` Godot's dummy renderer never emits
`RenderingServer.frame_post_draw`. Every capture path in `boot.gd` awaits it —
`--capture` since P1, `--film` since P3, `--shots` as of this milestone — so all
three blocked forever. Isolated by the difference between two runs:
```
godot --headless --path port --quit # prints, exits 0
godot --headless --path port -- --screen=… --capture=… # no output at all, killed at 40 s
```
The second produces **zero bytes of output** before it is killed, because
Godot's stdout is block-buffered and never flushes. So the observable behaviour
of an unattended headless capture was: silence, forever. In a loop, a job that
waits reads as a job still working — this is the failure mode that costs a whole
iteration and leaves nothing behind to say what happened.
Two changes, and deliberately not one:
* `--capture`, `--film` and `--shots` **refuse at startup** under `--headless`,
naming the flag and printing the `xvfb-run` line that does work. Refusing
early rather than at the first frame means the run does not die halfway
through a filmstrip with some frames written.
* `--script` **no longer waits for a drawn frame when it is not going to
photograph one.** Navigation is checkable where nothing draws, and that is
worth keeping: `godot --headless --path port -- --menu --script=…` now walks
the menus and exits 0 in about four seconds, which is a cheap regression check
that needs no X server at all.
The Xvfb path is unchanged and is what produced the P5 artifact.
---
## Refutation — the focus ring IS drawn rotated, and it is not at 0° in either capture
Attempted against the Decoder's `7eeae30` (*"re(ui): the focus ring SPINS, the
game draws it, and the leaf owns the f record"*), point 2: that in the
OPTIONS-focused capture the ring's bright head sits in a different angular
position from the sprite's own, caught mid-spin. **It survives**, and the
evidence is stronger than what was claimed.
Chosen for refutation because it is exactly what PROTOCOL says to aim at: a
claim the port is about to build on, resting on an estimator (a brightest-region
centroid) whose own control the Decoder reported as ±19.8°.
### The test, and why it needs no absolute registration
`live-main-menu.png` has `ptbtn01` focused; `live-main-menu-options-focused.png`
has `ptbtn04` focused. Both draw **the same sprite**, `ptbtneff01.png` — the
export confirms the two focus records name the same file. So the two captures
contain two instances of one 42×46 image, 240 px apart in design space, and the
question *"is it drawn rotated"* becomes *"are these two crops the same image
at a different angle"* — which needs no crop offset and no reference to our own
renderer.
Method: sample each ring into a 360-bin **angular luminance profile** over the
annulus band (r = 9…15 px, bilinear, 0.5 px radial step) and circularly
cross-correlate. A rotation about the centre shifts that vector and changes
nothing else.
### The instrument was run through two controls before it was believed
| control | result |
|---|---|
| rotate a capture's own ring by a known 0/30/90/150/210/270/330° and recover it | **0° error on all seven**, peak corr 1.000 |
| the same estimator on a ring-free 60×64 patch of the *same* capture | peak corr **0.369** — it does not manufacture a match |
### The measurement
On one shared centre for all three images, so a centroid difference cannot
masquerade as a rotation:
| pair | best shift | peak corr | corr at 0° |
|---|---|---|---|
| capture A vs capture B | **134°** | 0.968 | 0.064 |
| sprite (unrotated) vs capture A | **76°** | 0.969 | 0.295 |
| sprite (unrotated) vs capture B | **210°** | 0.948 | 0.181 |
210 76 = 134: the three measurements are internally consistent, which nothing
in the method forced them to be. Sweeping the centre by ±2 px moves the A-vs-B
answer over 117…161° while the peak correlation stays 0.9+ across the middle of
that range, so the **magnitude is ~134° ± ~15°** and the precision claim stops
there.
Evidence sheet — sprite, capture A, capture B, each cropped at the declared
`42×46+500+156` / `+500+396` — handed over as `share` id
`1788002507-afe1ad843789`. The phase difference is obvious by eye; the numbers
are here so it is not only obvious by eye.
### The two things this settles for the port
1. **The game draws `rotation_deg` on an element the English boot path shows.**
This is a second, independent confirmation on a different screen and a
different element from the `ptloop` sweeps, and it moves HANDOFF **ask 4**
(*should the port draw rotation*) off "changes nothing at rest" — it changes
the main menu's focus marker, in every frame.
2. **0° is not a pose the running game shows.** `screen_view.gd` currently draws
the ring at its `rest` pose, which is `rotation_deg 0`, and both captures put
it at 76° and 210°. So the port's focus marker is **known** to be wrong, not
suspected — and the comment in `screen_view.gd` now says which two numbers it
is wrong against.
### Registration, as a by-product
The ring's annulus centroid lands at (32.94, 36.63) and (33.30, 38.90) in
windows whose design-space prediction under a **zero crop offset** is
(33.0, 37.0). Within ~0.4 px on the better-thresholded of the two. That
corroborates `ORACLE-CAPTURES.md`'s *"1279×675, top-left aligned"* directly, on
a feature nobody chose for the purpose.
⚠️ Do not read the earlier P5-groundwork note *"button text bands land at design
y + 23"* as a crop offset — it is an offset **within** the button sprite, and
the two were nearly confused here.
### What the port did NOT do about it
It did not start spinning the ring. The period is a **guess with two unknowns**
and both belong to the Decoder:
* the keyframes are `t=120, rot 0` then an **untimed** `rot 360`. Under HANDOFF
Q1's replicated reading (*"`+36` is the time the NEXT pose is reached"*) that
is one revolution in 120 units = **2.0 s** — but this port's `pose_at`
implements the *other* reading, and switching it is a change to every screen's
animation timing, not a P5 change;
* *"groups hold"* (settled 2026-08-28) predicts the ring stops at 360° = 0°.
Both captures show it elsewhere. That is either a spin that loops, or two
captures both taken inside the first two seconds of focus. **The port cannot
tell those apart**, and a wrong answer here is a visible continuous rotation
on whichever button the player is sitting on.
Filed in `BLOCKED.md` and asked over the message channel. What settles it is two
frames of one focused button a known time apart.
---
## P5 end to end — and the title does not say `PRESS Ⓐ`, 2026-08-29
The gate walk above starts on a screen. This is the whole thing, unattended, in
one run — the sequence PORT-MISSION names as the objective:
```sh
xvfb-run -a godot --path port -- --boot --play \
--script=accept,down,down,down,down,accept,cancel,cancel --shots=/tmp/e2e
```
```
screen publisher_logo … settles at t=235 (3.917 s)
-> developer_logos at 4.70 s
-> video ADV at 8.60 s
video ended at 151.91 s
-> title at 151.91 s
boot sequence complete after 156.30 s, holding on title
menu on title
script[1] accept (A) -> main_menu
script[6] accept (EXTRAS) -> extras
script[7] cancel (B) -> main_menu focus restored to ptbtn05
script[8] cancel (B) -> title
script complete after 166.76 s on title
```
Publisher wordmark → developer logos → `ADV` → title → Ⓐ → main menu →
navigate → Ⓐ → `EXTRAS` → Ⓑ (focus restored) → Ⓑ → title. Contact sheet shared.
Two smaller things this run found, both fixed here:
* the boot step's `why` in `authored/flow.json` still said *"nothing takes the
title's place until P5 gives it somewhere to go"*. P5 has. Rewritten to say
what is actually true — `--boot` still **stops** on the title, and `--play`
**hands the held title over**; the stop is not a bug and the handover is not
another boot step.
* an empty focus printed as a line that trailed off, which reads like a value
went missing rather than like there is none. The title is a screen with no
`buttons` that still takes Ⓐ, so it prints
`(none -- this screen has no focusable item)`.
Also confirmed on the way: entering a submenu **directly** (`--menu=extras`) and
pressing Ⓑ enters the parent at its authored initial focus, not at a restored
one — there is no history to restore, and `MenuFlow.cancel` only claims a
restored focus when the stack agrees about where it is going.
### 🔴 The port's title does not tell the player to press Ⓐ
Found by running the objective end to end, which is the only thing that would
have found it: the boot's last step is `title` (build 4), and **build 4 has no
`PRESS Ⓐ BUTTON` plate**. P5 has now made Ⓐ the only way off that screen.
This is not a guess about the art. Both states are captured off the running
game and they differ by exactly that plate:
| | capture |
|---|---|
| title **without** the plate | `title-builds/live-title-build4-no-plate.png` |
| title **with** the plate | `title-builds/live-title-press-a.png` |
And the plate is already exported — `press_start`, `GP_TITLE` build 2 (HANDOFF
Q2), sitting in `export/screens/title/` unused by anything.
**This is P3's gate, not P5's, and P5 is what exposed it.** Recording rather
than fixing, for two reasons:
1. Which state an idle post-boot title shows — build 4 alone, build 4 with the
plate over it, or build 4 *then* the plate after a delay — is **behavioural**,
and the port has no oracle for a sequence. The game demonstrably has both
states; nothing here says which one follows the intro movie. That is the
Decoder's.
2. Showing it would mean **drawing two builds at once**, which this port has
never done — every mode loads exactly one screen. That is a real change to
`ScreenView`, not a line in `flow.json`, and it should not be smuggled in
under a navigation milestone on the strength of "it looks more right".
Filed in `BLOCKED.md`. Not blocking: P5's gate is Ⓐ into a submenu and Ⓑ back,
and both work.
## P6 — menu audio, 2026-08-29
The disc's menu sound reaches Godot as Ogg Vorbis: three cues and one music bed.
Nothing in `port/` has heard of XMA, `sound.pak` or `Static.slb`, and nothing in
it reassembles anything — `sylpheed_formats::media` does that and the exporter
converts what it hands back.
### The cue offsets moved OUT of the exporter, into `authored/`
The previous iteration left `crates/sylpheed-export/src/audio.rs` holding the
three `Static.slb` offsets as a Rust `const CUES`. That is wrong under MISSION
§3 and the fix is the first thing this iteration did.
Those offsets are **measured**, not decoded. `Static.slb` has no `RIFF`, no seek
chunk and no container: it is a packed run of whole 2048-byte XMA1 packets, and a
wave is defined *only* by `(offset, packet_count)`. Both numbers came from the
running game — Canary with `--xma_param_probe=true` prints a stream's packet
count and first 32 bytes when it is played, and searching those bytes in the bank
gives the offset (HANDOFF Q8).
A measured value compiled into the exporter is **a measurement wearing the
costume of a decoded field**. It reads as though the exporter derived it from the
disc; nobody deletes it when the real answer lands, because nobody can see that
there is anything to delete. So the table is `authored/audio.json` `se.*`, each
row carrying its own `why`, and the exporter holds no cue table at all.
`crate::video::MOVIES` stays a `const` in the exporter, and the contrast is the
point: Q9 **decoded** that mapping off the movie manifest on the disc. Same
shape, different provenance, different home.
### `name_match` is a field, and its absence means something
Q8 names `SE_UI_CURSOR` for the move cue by **name match against the authors' own
identifiers** — a plausible guess, not the measurement. For Ⓐ, Q8 is explicit
that the wave was *not* separated between `SE_UI_DECIDE` and
`SE_UI_SUB_WIN_OPN`, so no name is claimed at all.
`name_match` therefore travels beside every cue in `authored/audio.json` and in
`manifest.json`, and **an absent one means nobody claimed a name — never that
the binding is unknown.** The binding is the measured part. Collapsing the two
would turn "we did not separate two candidates" into "we do not know what this
sound is", which is a different and much weaker statement than the one the RE
agent actually made.
### The BGM is NOT a choice, and this port spent an iteration believing it was
The first draft of `authored/audio.json` picked `BGM_001`, wrote a careful `why`
explaining that the choice was arbitrary, and was **wrong**.
`docs/port/BLOCKED.md` carried the row that caused it: *"not on the disc … the
port is choosing a track, and that choice is authored."* The menu's music is
**`BGM_103`**, and it is in HANDOFF at **`9ca1eb5`** — the exact commit that page
says it was reconciled against. So this was not staleness. **The row was wrong
when it was written.**
What HANDOFF says is a negative *with a bound*, and the bound is the entire
content of it:
> the **tables** cannot say — `SOUNDS`, `FILES` and the bank headers name no
> screen. `GamePart_Title`'s phase handler `sub_821C5580` carries `li r5, 1103`
> into a sound call; cue 1103 is `BGM_103`; and `BGM_103.slb`'s two declared
> waves (3 876 864 / 3 930 112 B) are byte-for-byte the two streams the XMA probe
> saw decoding at the main menu. Static code, disc census and runtime all agree.
> **"The port does not have to choose a track."**
The failure is worth naming precisely, because "read HANDOFF more carefully" is
not the lesson — `BLOCKED.md`'s own staleness check passed, twice, and would pass
again. **A negative summarised without its reach reads as a bigger negative than
it is.** "The tables cannot say" became "it is not on the disc", and one word of
scope was the whole answer. A row in `BLOCKED.md` must quote the reach.
It also cost a second thing worth recording: the port would have shipped a menu
playing the wrong music with a confident `why` beside it saying the choice was
deliberate. That is exactly the shape of error this project's vocabulary exists
to prevent, produced *by* the machinery meant to prevent it.
### The bank name carries `.slb`, and that is how the mistake surfaced
`BGM_001` is not in `sound.pak`. `BGM_001.slb` is — `media::read_sound_bank`
looks up `name_hash(name)` against the TOC, and the TOC hashes the **file name**.
`Static.slb` worked from the first run only because the RE finding happens to
write it with its extension.
So the wrong track never played: the export failed loudly with *"BGM_001: not
present in sound.pak"*. That is luck, not design — had the draft picked a name
that happened to resolve, nothing would have complained. The `why` in
`authored/audio.json` now records both the correct name and why the short form
fails.
`export_bgm` now distinguishes the two cases it was conflating. A bank that is
**not in this disc's `sound.pak`** is a missing asset: the manifest takes a
warning and everything else still exports. Any other failure — a short read, a
malformed bank — still stops the run, because a partly-read bank produces a file
that plays.
### The two stems are summed. That part is not a choice
Q10 also measured that a bank's sub-waves are **two stems of one performance,
played together** — sample-synchronous, equal duration, on all 32 banks.
Concatenating them is explicitly wrong.
Emitting them as two files would be wrong for a second, independent reason:
MODDING rule 1 is *one logical asset, one file*, and handing a modder two stems
to line up by hand is precisely the reassembly the exporter exists to have
already done. `amix=normalize=0` sums at unity rather than halving, because
halving is a mix decision nobody made — and because a sum can clip, the peak is
**measured and reported** rather than silently corrected.
### The loop seam is ugly on purpose
No loop-point field has been identified. `loop: "restart"` replays from sample 0,
so a listener hears the track's own fade-out and its trailing silence before the
music comes back.
Trimming to the fade would sound better and would be **worse**. It would invent a
loop point, and an invented one is indistinguishable from a decoded one a month
later — which is the failure mode this whole project is organised against. The
seam stays audible until a loop point is measured or a capture of the real menu
looping settles it.
### When a cue fires — two rules measured, one authored
* **Move** fires on a press that *actually moves the cursor*. `MenuFlow.move()`
already returned whether it did, which is why left/right stay silent by
construction rather than by a rule written twice (Q5: ⬅➡ do nothing, and Q8:
they play nothing).
* **Ⓐ and Ⓑ** fire when the press *does something*, and not when nothing is
bound. 🟡 **This half is authored and NOT measured** — nobody has watched the
game take a dead press. Silence invents less: a sound the game does not make is
a wrong fact you can hear, while a missing one is a gap. `blocked` counts as
doing something, because those destinations *were* measured off the running
game and are missing from this export, not from the game.
* The bed starts when the menu becomes live and **carries across submenus**.
`play_bed` is idempotent, because music that restarts every time you press Ⓑ is
the kind of wrong that reads as "the audio works".
### `--audio=` records the Master bus, because neither container has a sound card
`docs/port/AUDIO-VERIFICATION.md` §2. An `AudioEffectRecord` on the Master bus
captures the mixed output from inside a headless run with no device at all, and
that is the only thing that closes the loop the file opens: comparing an exported
Ogg against the disc proves the **asset** is right and says nothing about whether
the engine ever reached it.
The run prints `AudioServer.get_driver_name()` beside the file it wrote, because
"recorded under a dummy driver" is a weaker claim than "heard" and the write-up
has to be able to say which one it is making.
The WAV is saved in `_exit_tree` rather than beside each `quit()`. There are
eight of those, and the one that would get missed is an error path — exactly the
run whose audio somebody wants to look at.
### `check` now refuses silence and clipping
`sylpheed-export check` gained an `audio` pass, and two of its rules are content
checks rather than schema checks. That is deliberate. Silence is *the* audio
failure that looks like success — a file of the right duration, the right channel
count and the right size, full of zeroes — and it passes every structural check
there is. Clipping is the other one, and the BGM can produce it because it is a
sum at unity gain. The exporter measures both at export time; `check` refuses a
tree whose peak is ≤ 90 dBFS or ≥ 0 dBFS.
Neither is a judgement about whether the audio is the *right* audio. Nothing in
that binary can know that, and `BLOCKED.md` says which parts are still authored
guesses.
### A bug worth naming: the temp name ate the file extension
`run_ffmpeg` wrote to `.back.ogg.partial` — the temp-name-then-rename discipline
this project uses everywhere, and which `AUDIO-VERIFICATION.md` records as
already having caused a confident wrong number once.
ffmpeg picks its muxer **from the output filename**, so that is not a slightly
uglier temp name; it is a hard failure before a byte is written: *"Unable to
choose an output format for '.back.ogg.partial'"*. `video.rs` already had the
right shape (`.ADV.partial.ogv`) and this function was written from scratch
without looking at it. The extension goes last.
### Refutation — the three Q8 cue durations, checked end to end
**The claim:** HANDOFF Q8 publishes three cue lengths — move **0.533 s**
(8 192 B, 4 packets), back **0.344 s** (4 096 B, 2), confirm **1.016 s**
(12 288 B, 6). P6 is built directly on top of these, which by PROTOCOL's own rule
makes them the right thing to attack: refutation is cheapest where the other
agent is most confident, and most valuable where the port is about to build.
**Why they looked attackable.** The three do not share a rate. Seconds per
packet is 0.133, 0.172 and 0.169 — the move cue is 22 % off the other two. If a
packet were a fixed span of audio, at most one of these numbers could be right.
**Why that is not a refutation.** An XMA1 packet is 2 048 bytes of *bitstream*,
not a fixed span: it carries a variable number of 512-sample frames. At 48 kHz a
frame is 10.667 ms, and the three durations come to **50.0, 32.3 and 95.3
frames** — near-integers, which is what a variable-frames-per-packet encoding
looks like and is not what an arithmetic slip looks like.
**The measurement.** The exporter reads `(offset, packet_count)` through
`media::se_wave_riff`, decodes, and `ffprobe`s the finished Ogg:
| cue | Q8 claims | exported file measures |
|---|---|---|
| move | 0.533 s | **0.533 s** |
| back | 0.344 s | **0.344 s** |
| confirm | 1.016 s | **1.016 s** |
**Verdict: survives, exactly, at every published digit.** Recorded as a survival
rather than a pass, because that is what PROTOCOL asks for — a claim that has
survived an attempt is stronger than one nobody challenged, and the corpus should
say which it is.
⚠️ **Reach, stated so nobody over-reads it.** This is not independent of Q8: the
durations were derived from the same packet counts the exporter feeds in, so what
it confirms is that reading those `(offset, packets)` through
`sylpheed_formats::media` yields streams of exactly the claimed length — i.e.
that the *transcription* into `authored/audio.json` and the assembly path are
right. It does **not** confirm that these three waves are the sounds the game
plays on those three events; that is Q8's own measurement, taken by playing them,
and this port has no oracle to re-take it with.
The attempt did find something, just not here: see the BGM section above, where
the port's *own* `BLOCKED.md` row failed the same kind of check.
### The BGM bank has three sub-waves and HANDOFF says it has two
`media::sound_bank_riffs("BGM_103.slb")` returns **three**. HANDOFF Q10's census
says a music bank is *"exactly two waves of identical duration (32/32 banks on
the disc)"* — and that census is itself a correction, of an earlier reading that
called `BGM_001` three sub-waves and was refuted with "the 10 KB is the bank
header".
The third comes from `sylpheed-formats/src/slb.rs:380`, `to_xma_riffs`: when a
bank has a leading headerless packet region ahead of its first `RIFF`, that
region is emitted as a sub-wave. It exists because the voice path needs it —
`VOICE_D_453` decoded to 0.14 s without it. `docs/re/REFUTED.md` already records
the same region as what makes `BGM_106``BGM_109` "break the two-wave rule".
**The port sums all three and says so in the manifest.** That is not the
appealing answer — dropping sub-wave 0 would give a file matching the census, and
it would have been one line. It is the correct one: *which bytes belong together*
is the question `sylpheed_formats::media` owns, MISSION §2 names re-deriving it
here as the single easiest thing in this project to get subtly wrong, and "the
decoder returned something the corpus does not predict" is a finding to report,
not a number to quietly adjust. Adjusting it would also have destroyed the
evidence: a corrected export looks exactly like a correct one.
So the export ships the decoders' answer, the manifest carries a warning naming
the contradiction, `BLOCKED.md` has the row, and the Decoder has the pointer.
Until it comes back, **the menu plays a sum of three things where the census
predicts two**, and every one of those places says so.
### Clipping — and a comment of mine that argued for the thing that clipped
The BGM came out at **+1.8 dBFS**. The comment above the code that produced it
said `amix=normalize=0` sums at unity "because halving is a mix decision nobody
made".
That was wrong in both halves. Unity summing *is* a decision, and it is the one
that clips. And 1/n is not a taste call: it is the smallest constant that makes
an n-input sum of unity-scale signals provably clip-free, which is precisely the
reasoning `video.rs` already carried for its 0.4142-normalised 5.1 downmix — in
this same repository, written by this same port, and not looked at. It preserves
the stems' relative balance exactly, which is the only thing about the sum that
Q10 settles.
It is written as an explicit `volume=` rather than left to `amix`'s
`normalize=1` default, so the coefficient appears in the manifest's command line.
A default is a decision nobody made and it can move under an ffmpeg upgrade —
the same argument MISSION §6 makes about the downmix matrix.
**The `confirm` cue is a different case and is not "fixed".** It lands at
+0.18 dBFS, and it is a single wave off the disc with no arithmetic of ours in
it: the disc masters it near full scale and a lossy decode of a near-full-scale
signal overshoots by a fraction of a dB. Attenuating it would mean altering a
game asset to make one of our own numbers smaller. So `check` bounds the two
kinds differently — a `bgm` peak ≥ 0 dBFS is refused outright, because it is our
sum; an `se` is refused only above **+1.0 dBFS**.
🟡 That +1.0 is a **judgement and not a measurement**, and it is the weakest
number in P6. Nobody has measured the overshoot distribution across a corpus of
cues. If a cue ever trips it, the right response is that measurement, not a
looser bound.
## P6 gate — the audio is in the mix, and a null control says which part
No container here has a sound card, so "P6 works" cannot be answered by
listening. `docs/port/AUDIO-VERIFICATION.md` splits the question into three, and
these are the two that need no device.
### 1. The exported files, measured off the finished assets
```
se back -> audio/se/back.ogg (0.344 s, peak -5.7 dBFS)
se confirm -> audio/se/confirm.ogg (1.016 s, peak +0.2 dBFS)
se move -> audio/se/move.ogg (0.533 s, peak -1.4 dBFS)
bgm main_menu -> audio/bgm/main_menu.ogg
(87.744 s, peak -7.7 dBFS, bank BGM_103.slb, 3 sub-waves)
```
`sylpheed-export check export` passes: 16 screens validate, and every audio entry
carries a peak and a duration inside its bounds. The three cue durations match
HANDOFF Q8 at every published digit — see the refutation record above.
### 2. The engine, recorded off the Master bus
```
godot --path port -- --menu --script=down,down,accept,cancel --audio=…/p6.wav
→ recorded 6.037 s of Master bus (driver Dummy)
peak 0.0 dBFS, RMS 21.1 dBFS
```
**Non-silent is not the claim.** A WAV of the right duration full of the *bed*
would look exactly like this, and the cues could be missing entirely. So the cue
was isolated with a **null control**: the same scripted walk with ⬅ in place of ⬇.
Left/right are measured no-ops (Q5) and fire nothing, so the two runs differ by
exactly two move cues and nothing else — same screens, same transitions, the same
Ⓐ and Ⓑ cues in both, the same bed.
| | RMS |
|---|---|
| walk with two ⬇ presses | 21.9 dBFS |
| walk with two ⬅ presses (null) | 22.1 dBFS |
| **difference** | **34.6 dBFS** |
The difference is not spread over the run. It is **one burst beginning at
t = 1.10 s and lasting 0.55 s** — two overlapping 0.533 s move cues — with 22 of
237 windows above 70 dBFS and silence everywhere else, including across the Ⓐ
and Ⓑ presses, which cancel because both runs make them. That is the cue reaching
the bus, separated from the music that was playing over it.
### The control that proved nothing, kept because it nearly passed
The first attempt paired `--script=down,down` against `--script=left,left`. The
difference was **bit-identical zero**, which reads as "the cues never reached the
bus" and would have been reported as a bug.
It was neither. Both runs recorded **1.115 s** while the first press lands at
~1.17 s: the control ended before the event it was controlling for. A null result
from an instrument that was not running is not a null result — PROTOCOL's "run
your own instrument through a control" applies to the control too.
### What this does NOT establish
* **That it sounds right.** Everything above is correspondence and separation,
not judgement. A ten-second human listen still answers something no measurement
here does.
* **That the bed is at a sane level against the cues.** 🔴 The Master bus peaks at
**0.0 dBFS** in the four-step run — the `confirm` cue is +0.2 dBFS on its own,
so any music under it puts the mix on the ceiling. Per-file levels are the
disc's and are fine; the **runtime** mix has no headroom. The port has not set a
bus balance, because nothing measures one and an invented balance is the same
class of mistake as an invented loop point. Recorded here rather than fixed
quietly.
* **That "Dummy driver" means heard.** It does not, and the run prints the driver
name so a write-up cannot forget to say so.
### One bug, in two dialects, both about a temp filename
The temp-name-then-rename discipline this project uses everywhere broke twice in
this milestone, in two different tools, for the same underlying reason: **tools
dispatch on the extension, so a temp name must preserve it.**
* `run_ffmpeg` wrote `.back.ogg.partial`*"Unable to choose an output format"*,
a hard failure before a byte was written.
* `boot.gd` wrote `p6.wav.part` → `save_to_wav` **appends** `.wav` when the path
does not end in it, producing `p6.wav.part.wav`; the rename then failed to find
its source, its return value was not checked, and the run printed a success
line naming a file that did not exist.
The second is the more dangerous shape, and it is the one this project has
already warned itself about: a confident line of output pointing at nothing. The
rename's return is now checked and the failure is loud.
## P3, reopened — the boot title was missing the `PRESS Ⓐ` plate, 2026-08-29
P3 passed its gate with a boot that ended on build 4 alone. `BLOCKED.md` carried
that as 🔴 from the start: both states were captured, so the art was never the
question — the *sequence* was, and it is behavioural, so the port had no oracle
for it.
It is answered. `docs/re/title-plate-delay-measured.md`
(`auto/no-disc-and-menu-captures` at `fb536df`, **not on `main`** at the time of
writing) measures two independent boots: the title presents **without** the
plate, and the plate arrives **2.13 s** later, the two runs agreeing to 6 ms.
### Two builds at once, as two `ScreenView`s
`ScreenView` draws one screen. The obvious change was to teach it about a
subordinate overlay screen; the change made was to put a **second `ScreenView`
in the same `SubViewport`**, after the first.
That is what "two builds at once" actually is. Each build has its own timeline,
its own textures and its own hold — the plate's group runs independently of the
title's, which is the entire content of the finding — and Node2D siblings already
paint in tree order. The alternative would have put an `if overlay` in every
method that walks elements, and would have expressed the same information less
directly. The export's `paint_order` still means what it always meant: an
ordering *within* a build.
### The delay is timed from where build 4 stops animating
Not from where the title first appears. This is the finding rather than a detail:
measured from first-draw the two oracle runs differ by **0.48 s**, because the
build-in itself ran 1.64 s and 2.13 s and the emulator's frame pacing during an
animation is not the game's clock. Measured from settle they differ by 6 ms.
So `_boot_done` — the moment the sequencer already had for "this screen has
reached its hold" — is the landmark, and the overlay is due `after_settle_seconds`
later. A number taken from the wrong instant here looks exactly like a
measurement.
### The overlay is attached to the BOOT STEP, not to the `title` screen
What was measured is the boot title. Whether the plate is there when the title is
reached *again* — by Ⓑ from the main menu, or after the attract movie — is not
measured, and hanging the overlay on the screen would quietly claim that it is.
So it lives on the boot step in `authored/flow.json`, and `_drop_overlay` takes
it away with the screen it belongs to. `BLOCKED.md` carries the gap.
### Refutation — the RE agent's instruction contradicts the RE agent's measurement
**The claim under test**, quoted from the finding's *"What the port should
author"*: draw build 4, *"when build 4 has settled, wait **2.13 s**, composite
build 2 over it"*.
**It does not reproduce the measurement it came from**, and the gap is 3.97 s.
Build 2 is not a static plate: it has a group, and this port plays groups.
`press_start` has one element, `ptbtn00`, and its `fade_argb` reads
```
t=214 0x00ffffff pos (383, 560) invisible
t=236 0x00ffffff pos (383, 550) still invisible, having slid 10 px up
t=238 0xffffffff full alpha
t=244 0xffffffff holds
— 0x00ffffff the exit, untimed
```
At the measured 60 units/s that is **3.967 s** from the group's start to full
alpha. Compose the instruction with the group and the plate is first *visible* at
settle + 2.13 + 3.97 = **settle + 6.10 s**. What was measured — the glyph counter
leaving its no-plate value of 154 — is the plate becoming visible at **settle +
2.13 s**.
Neither obvious reconciliation works:
| reading | plate visible at | measured |
|---|---|---|
| both groups start together | 3.97 s (build 4 settles at **4.350 s**) — i.e. 0.38 s *before* settle | settle + 2.13 s |
| build 2's group starts at settle | settle + 3.97 s | settle + 2.13 s |
| build 2's group starts at settle + 2.13 s (the instruction) | settle + 6.10 s | settle + 2.13 s |
To land on the measurement, build 2's group has to start **2.51 s** after build
4's, which is not a landmark of anything.
**Verdict: the instruction is refuted as written; the measurement is untouched.**
The measurement is an observation of the running game and this port has no
standing to doubt it. What is refuted is the step that turns it into an
authoring rule, and that step is an interpretation.
**So the port ships the instruction, not its own arithmetic**, prints the
discrepancy on every boot, and files the row. This is the same call as the BGM
sub-waves and for the same reason: reconciling two of the RE agent's numbers is
a decoding question, and a port that quietly picks the one that looks right
destroys the evidence — a corrected boot looks exactly like a correct one.
The first thing to check is about the instrument rather than the game: is *"title
settled"*, the glyph counter first reading 154, the same instant as the port's
last-element settle (t=261, 4.350 s into the group)? If that landmark is earlier,
the gap closes with nothing else moving.
### Refuting the port's own claim: things in this export DO pulse
`BLOCKED.md` has carried this since P2, under the port's own raised question
about whether groups loop:
> no element's alpha reverses direction anywhere in this export, so nothing
> pulses, which removes the obvious reason to expect a loop without disproving
> one.
**`ptbtn00` reverses.** `0x00``0xff``0x00`, in the table above, in the
export, the whole time. The claim was never checked against `press_start`; it was
checked against the screens P2 happened to be animating. The RE agent has now
measured the running game pulsing this exact element at a mean 2.24 s.
So the reason to expect a loop is back — and the port still does not draw one,
because **no reading of this group produces 2.24 s**: the whole group is 268
units = 4.47 s, and from its first keyframe 54 units = 0.90 s. The plate is drawn
arriving and then holding at its settle (t=238, alpha `0xff`), which is what
every other screen does and what the static oracle capture
`live-title-press-a.png` shows. Which instant a repeat restarts from is filed,
not guessed.
### `--boot --capture=` — one frame instead of six hundred
The boot had no artifact of its own except `--film`, a PNG every 0.25 s for the
whole 156 s run, to answer one question: is the plate on top of the title at the
end. `--capture` was a `--screen`-only flag taken in `_ready`, which for a boot
run is 150 s too early. It is now deferred to the end of the sequence when
`--boot` is given.
### P3 gate — the boot ends on two builds
```
godot --path port -- --boot --capture=…/p3-plate.png
→ boot sequence complete after 155.86 s, holding on title
overlay press_start due at 157.99 s (+2.13 s after settle)
overlay press_start raised at 158.00 s, 1 element(s), settles at t=238
⚠ plate raised at settle+2.13 s but its own group reaches full alpha 3.97 s
later, so it is first VISIBLE at settle+6.10 s -- the measurement is
settle+2.13 s.
boot ends on title + press_start at 161.99 s
drew 16: ptbase2, ptloop01, …, ptcopyright
overlay press_start at t = 261.00 units, drew 1: ptbtn00
```
The PNG shows the title logo with **`PRESS Ⓐ BUTTON`** under it — build 4 and
build 2 in one frame, which this port had never drawn.
Two things the run made obvious and that are now fixed:
* **The capture reported only the base build's elements.** The first composited
capture printed `drew 16` and no mention of the plate, which reads as though
the overlay had not drawn at all. The overlay gets its own line; folding its
elements into the first list would have reported a screen that does not exist.
* **`--screen=<a> --overlay=<b>`** raises the same composite immediately, by the
same code path, with no delay. It exists because the only other way to see two
builds was a 156 s boot of which 137 s is the intro movie — and under Xvfb's
software Theora decode that is several minutes to answer "is the plate on top
of the title". It applies **no** delay: the delay is a measurement and lives in
`authored/flow.json`. The boot-mode narration is suppressed there, because a
log line that describes a sequence it is not running is worse than no log line.
## P5 — the focus ring spins, 2026-08-29
The ring was drawn at 0° and the file said so: *"THIS IS KNOWN TO BE WRONG, and
is drawn anyway because the right answer is a guess."* What was missing was the
**period**, and it is now measured — `docs/re/focus-ring-spin-measured.md`
(`auto/no-disc-and-menu-captures` at `4fa3099`): a continuous spin, from eight
evenly spaced autocorrelation peaks over nine revolutions, **with no angle
estimated anywhere** — both angle estimators failed their own controls and were
not used.
### The period comes off the disc; the RE agent supplied only that it repeats
`ptbtneff01` declares two keyframes that differ in **nothing but**
`rotation_deg`, 0 → 360, the first timed at `t = 120` and the second untimed.
The port turns once per **120 units**. Nothing is authored: the number is on the
disc, and what the measurement adds is that the turn **repeats** rather than
stopping at 360 = 0, which "groups hold" could not distinguish because those are
the same pose.
`ScreenView.spin_period_units` is the rule, and it is structural and narrow:
exactly two keyframes, differing only in rotation, by a full 360, first timed and
second untimed. **Disc-wide check over this export: 16 of 212 elements match, and
all 16 are focus rings** — `ptbtneff01` on the five main-menu buttons and
`ptbtneff02` on the three `EXTRAS` buttons, in both locales, every one declaring
`t = 120`. Zero false positives.
That check is the point rather than a formality. The measurement was taken on
**one** button of **one** screen; a rule that also caught something else would be
extrapolating it to elements nobody watched.
⚠️ It is a rule about **shape**, not a decoded field. Nothing on the disc says
"this loops". The day a loop flag is decoded, this goes.
### Verified on the port's own render, with the RE agent's own control
Captures at `--time=` 2.0 … 4.0 s on the settled main menu, `ptbtn01` focused:
| | |
|---|---|
| t=2.0 vs t=4.0 (one full period apart), **whole frame** | **0.0000 / 255** — bit-identical |
| t=2.5, 3.0, 3.5 against t=2.0, inside the ring's box | 3.60, 3.71, 3.58 / 255 |
| sum of box luminance across **eight** phases | spread **0.027 %** of the mean |
The last row is deliberately the RE agent's own observable: they separated
rotation from a brightness pulse by showing total annulus brightness is conserved
while per-bin brightness moves. The port's render conserves it to 0.027 % (theirs
was 0.4 % over 16 s, with capture noise in it). A filmstrip of the four
quarter-period phases shows the bright head at top, right, bottom, left.
### Two things it does not settle
* **Direction.** The port turns 0° → +360°, the sign the disc declares. No signed
angle was ever measured — the estimator that would have given one failed its
control and was not used.
* **Phase across a focus change.** The port drives the ring off the **screen**
clock, so moving the cursor does not restart the turn. The alternative — the
record's group restarting when the record is instantiated — is the stronger
claim, and the oracle run held focus on one button throughout, so nothing
separates them. Two frames straddling a focus change would.
## P3, corrected — the plate needs no authored delay at all, 2026-08-29
Last iteration the port refuted the RE agent's authoring instruction (*"when
build 4 has settled, wait 2.13 s, composite build 2"*) with arithmetic off the
disc, shipped the instruction anyway rather than pick between two of their
numbers, and printed the discrepancy on every boot.
**The refutation held, and the answer that came back is better than either option
the port offered: author nothing.** `5b0a6e6`.
### The premise that failed was the port's, and it will bite again
> 🔴 **`rest.t` is not when a screen settles.** It is the last *hold* keyframe
> before the exit.
Checked here rather than taken on trust. `title`'s `ptlogo1`:
```
t=26 (-116,-7) 150% a=0x00 the pre-roll
t=42 (179,186) 101% a=0xe0 it has arrived
t=251 (184,193) 100% a=0xff 5 px and 31 alpha steps later, 3.5 s on
```
It **stops moving at t=42** and then creeps for 209 units. `rest.t = 251` is the
end of that creep, not the arrival. The title's visible build-in is over at
**`t = 118`**, where `pteff01`, `pteff02` and `ptlogoall_eff` finish together.
Every reconciliation the port computed last iteration was wrong by exactly that
error: reading `rest.t` put build 4's arrival at 4.350 s instead of 1.967 s, and
the "2.51 s, which is not a landmark of anything" that looked so damning is
`(4.350 1.967) + 0.13` — the error itself, wearing a decimal point.
### One clock, and the interval is declared
| | units |
|---|---|
| build 4's last build-in ramp | `t = 118` |
| `ptbtn00` reaches `a = 255` | `t = 238` |
| **difference** | **120 units = 2.000 s** |
Measured: **2.138 s** and **2.132 s**. The 6.7 % is presentation rate — 120 units
in 2.135 s is 56.2 units/s, the emulator running 28.1 fps against a nominal 30,
and the corpus had independently measured the idle title at 28.5 fps *before*
these runs.
So `authored/flow.json` carries `"clock": "shared"` and **no delay**, `boot.gd`
raises the overlay when the step's screen loads rather than at its settle, and
`overlay.time_units = view.time_units` — assigned, not accumulated, because two
independently advanced clocks drift by a frame here and there and the whole
content of the finding is that 120 units is a fixed interval on one timeline.
⚠️ **The general hazard, stated by the RE agent and worth repeating where the
port will read it: discount a wall-clock number off that oracle by ~6 %.** It is
Canary's presentation rate baked into whatever it measures. A port at a true
30 Hz that authored 2.13 s would be visibly late.
### Refutation — two of the RE agent's numbers for the same 120 units disagree by 2 %
Both findings measure the same declared quantity: **120 keyframe units of wall
clock, during a static hold, in Xenia Canary.**
| | | implied presentation |
|---|---|---|
| plate: settle → plate, two runs | 2.138, 2.132 s → mean **2.135 s** | 28.10 fps |
| ring: one revolution, seven spacings | 2.18 2.16 2.18 2.16 2.16 2.20 2.20 → mean **2.177 s** | 27.56 fps |
| **disagreement** | **0.042 s = 1.97 %** | |
That is **seven times** the plate finding's own run-to-run agreement of 6 ms, and
it lands on the argument that finding uses to justify trusting itself: *"the
build-in is where frames are dropped; the static hold is not. A model in which
the game's own timing varied would have to move both."* Two static-hold
measurements are exactly what should agree under that model.
A second, smaller arithmetic slip in the same place: the ring page reconciles
2.177 s against a band of "27.628.8 fps", saying the measurement *"sits at the
top of that band"*. It does not sit in it. 60 rendered frames at 27.6 fps is
2.1739 s; the mean needs **27.56 fps** and the two slowest spacings (2.20 s)
need **27.27 fps**. Four of the seven spacings are above the band's top.
**Verdict: the containment claim is refuted; the spin, the period and the
reconciliation are untouched.** Either the presentation rate genuinely differed
between the two sessions — which the plate page's own corroboration argues
against for static holds — or the ring's revolution is not exactly 120 units.
The corpus should say which, because they are the same claim measured twice.
🟢 **Nothing in the port moves either way.** `spin_period_units` uses the
declared 120 units at 60 units/s = **2.000 s of port time**, which is the
true-30 Hz value both readings agree the disc means. This is a corpus
consistency problem, not a port one — which is why it is filed rather than
worked around.
### The corrected boot ended one build too early, and the capture showed it
Moving the plate onto the shared clock also moved the boot's exit, and the first
capture taken afterwards was **visibly darker** than the one before it. The cause
is `pteff00`, the title's black fade quad: it ramps `0xff000000``0x00000000`
over t=16…261, so at t=243 — where the run was quitting, `overlay.settle_time()`
after the overlay was raised — the frame is still ~7 % black.
The plate arrives at t=238; **build 4 is not finished until t=261**. The boot now
ends at the later of the two, and says which in the log:
```
-> title at 145.79 s
overlay press_start raised at 145.79 s, 1 element(s), settles at t=238
boot ends at 150.14 s, once both builds have arrived (t=261)
```
Worth recording because of how it presented: nothing failed, no warning was
printed, and the only symptom was a frame slightly darker than the previous
run's. A gate artifact that silently drifts is the failure mode this project
keeps meeting — and it was caught only because there was a previous capture to
compare against.
## P7 — the new-game intro, 2026-08-29
`S00A.wmv` has been in `export/video/` since P4 (MISSION §6 put both movies in
scope at once). What P7 needed was for something to *play* it and for the run to
end somewhere defined.
### The port skips two measured screens, and says so on screen
The real chain is **`NEW GAME``DIFFICULTY``SELECT DATA` → Ⓐ on a save slot
→ ~4.5 s → `S00A`** (HANDOFF Q4 measured the screens, Q9 decoded the movie and
then measured its onset off the running game at 0.961.000 with a strictly
monotone playhead over 25 consecutive 0.5 s samples).
`DIFFICULTY` and `SELECT DATA` are measured destinations that are **not
`GP_TITLE` builds**, so no screen file exists to go to. The port therefore jumps
from `NEW GAME` to the one thing in that chain it has.
That is a gap, not a sequence, and the whole design here is about not letting it
read as one:
* `MenuFlow.accept` returns a **new kind**, `video`, rather than folding this
into `blocked`. The caller has to announce the skip, and a distinct kind is
what forces it to.
* The runtime prints it every time:
`(NEW GAME) -> the real chain is DIFFICULTY -> SELECT DATA, then the movie.
Neither screen is in this export.`
* `authored/flow.json` carries `skipped_chain` as **data**, so the names of what
is missing live beside the decision rather than inside a GDScript string.
A port that quietly jumped from `NEW GAME` to the intro would be showing a
sequence the game does not have, with nothing on screen saying so. That is the
exact failure this project keeps meeting from the other direction.
### What happens after the movie is authored, and had to be
The game goes into **mission 1**. Gameplay is out of scope (PORT-MISSION §7), so
"returns to a defined state" is a decision, and P7's gate says as much. The port
returns to the **title**: the boot's own end state, so a run that finishes the
intro lands somewhere a player can start again from. Nothing measured says the
game does this, and `after_video.kind` is `"authored"`.
### The 4.5 s gap is left empty on purpose
Q9 measures the movie starting ~4.5 s after Ⓐ on the save slot. What is on screen
for those 4.5 s was never observed — the run that would have shown it hit the
documented `sub_823070B0` cache crash after `SELECT DATA`.
`GP_TITLE` **does** carry a loading screen (below), and 4.5 s is about the right
shape for one. That is precisely why it is in `BLOCKED.md` and not in
`flow.json`: a plausible filler that nobody watched is the kind of thing that is
indistinguishable from a measurement a month later.
### A script timeout that would have failed every movie
`--script`'s per-step timeout is 20 s, to stop an unattended run waiting forever
on a screen that never settles. `S00A` is **93.9 s**, so the first scripted
new-game run would have been killed at step 1 and reported as "never settled".
Raising the constant would have been wrong in the other direction: a movie stuck
at frame 0 would then hang the job, and a job that waits is worse than a job that
fails, because it does not look like a failure.
So the test is **liveness, not duration**: while `get_stream_position()`
advances, the deadline moves with it; a stalled movie still trips the same 20 s.
### Found while looking: `GP_TITLE`'s four unnamed builds are LOADING screens
`build_00`, `build_01`, `build_12`, `build_15` have never had names. Every
element in all four is `pgloading_*``pgloading_processing.png`,
`pgloading_circle1`, `pgloading_delta`, `pgloading_ring` — and `LOADING` is one
of the three screen names the RE agent read out of the title part's state
function.
Two variants: 0/1 carry 7 elements, 12/15 carry 10.
**They are not renamed here.** The archive's own pairing (adjacent for 2/3, `+3`
for 4…9 and for 10/13, 11/14) suggests 0 is 1's twin and 12 is 15's, but which
member of each pair is which **locale** is an inference, and a name is exactly
the kind of thing that stops being questioned once written. Handed to the RE
agent, who can answer it from a capture in one look. `BLOCKED.md` has the row.
⚠️ **And one of them is a second casualty of the `rest.t` problem.**
`pgloading_eff00.prm` on entries 12/15 is a full-screen black quad whose group
runs `0xff000000` at t=38 → `0xff000000` at t=48 → `0x00000000` untimed: black,
held, *then* clear. Its `rest.t` is **38**, where it is fully opaque. A port that
draws that screen at its declared rest draws **a black rectangle over the entire
loading screen**. The title's case only dimmed a frame; this one hides
everything. Filed with the `settle_time()` row it belongs to.
### Refutation — attempted on the fade-quad census; it survives, with a caveat
**The claim** (HANDOFF, on transitions): *"in `GP_TITLE` exactly the six screen
builds carry it while the six overlays do not"*, where "it" is the full-screen
black `.prm` quad *whose keyframe group is the transition*.
**The test**, over the whole export: count builds carrying a full-screen
primitive with black in its keyframes.
```
16 builds exported; 12 carry one.
Of the 12 `is_build` bundles (excluding the 4 authored splashes): 8 carry, 4 do not.
carry: title, title_jp, main_menu, main_menu_jp, extras, extras_jp,
build_12, build_15
do not: press_start, press_start_jp, build_00, build_01
```
8 and 4, not 6 and 6. But the two extras are `build_12` / `build_15`, and their
quad is a **different shape**:
| | transition quad (`pteff00.prm`, title) | loading quad (`pgloading_eff00.prm`) |
|---|---|---|
| | `0xff000000` t=16 | `0xff000000` t=38 |
| | `0x00000000` t=261 | `0xff000000` t=48 |
| | `0xff000000` untimed | `0x00000000` untimed |
| shape | black → clear → **black** | black → held → **clear** |
The transition quad returns to black on exit; the loading quad does not. Read
strictly — the quad *whose group is the transition* — the claim holds.
**Verdict: survives.** The refinement is worth recording anyway, because the
naive test over-counts by two and somebody will run the naive test. There are
**two kinds** of full-screen black `.prm` in `GP_TITLE`, and only one of them is
a transition.
## P7 gate
```
godot --path port -- --menu --script=accept --audio=…/p7.wav
```
```
menu on main_menu, focus ptbtn01
script[1] accept
(NEW GAME) -> the real chain is DIFFICULTY -> SELECT DATA, then the movie.
Neither screen is in this export.
-> video S00A at 1.18 s (/work/export/video/S00A.ogv)
video ended at 94.93 s
-> title (authored: authored)
menu on title, focus (none -- this screen has no focusable item)
script complete after 99.28 s on title
recorded 98.453 s of Master bus (driver Dummy)
```
The movie ran **93.75 s** against a declared 93.9 s, the run ended on the title,
and the Master bus recorded 98.453 s: `pcm_s16le`, 44.1 kHz stereo, RMS
**22.2 dBFS**.
**What this does not show, stated because it would be easy to imply otherwise:**
the recording contains the menu bed *and* the movie together, and this run did
**not** separate them. So it establishes that the engine reached an output for
98 s of a run whose middle 94 s was a movie — not that `S00A`'s own audio track
is in the mix. Separating them wants the P6 null-control method (a paired run
that differs only in the movie), and that is not done here.
🔴 **Peak 0.0 dBFS again.** The same runtime-headroom problem P6 filed: per-file
levels are the disc's and are fine, the Master bus has no headroom, and the port
has set no bus balance because nothing measures one.
### One more file read while it was being written
`ls` reported the recording as **3 702 828 B**; `ffprobe` on the finished file
reports **17 367 084 B / 98.452608 s** — a factor of 4.7. `ffprobe` is right and
the `ls` caught it mid-flight.
`AUDIO-VERIFICATION.md` opens by naming this failure and the port has had the
temp-name-then-rename discipline since P6, which is what makes it worth writing
down rather than shrugging off: **the discipline protects a reader who opens the
path, and it does not protect a reader who stats it at the wrong moment.** Size
on disk is not a measurement of a file somebody else is still writing. Ask the
decoder, not the directory entry.