re: the title's arrived pose is rest, and the washed-out slab is a

MISSING dim quad

Both halves of what the port agent could not settle, answered against the
plate-free capture rather than against another renderer.

Rendering build 4 and edge-correlating to the capture of the real screen
gives 0.9163 at zero shift, 0.92/0.78/0.93 per band. The geometry of rest
is the title's arrived pose, so the timeline is not needed there.

The slab is the more useful half, and it is inverted from how it looked.
rest alone renders uniformly +13.14 too bright, R +12.35, G +13.58,
B +13.48. Drawing the .prm primitives collapses that to +0.55. The
element is pteff02.prm, the 25 percent dim at rest t=46 with fade 0x40,
and --primitives is OFF BY DEFAULT. So the washed-out cyan slab is not
something being drawn that should not be; it is a dim that should be
drawn and is not, and because the title art is blue-dominant the
shortfall reads as a cyan wash. Any consumer of screen render that omits
--primitives on this screen gets it.

Two residuals recorded rather than tidied. With the dim drawn the mean is
essentially exact but per-pixel agreement gets slightly WORSE --
edge-correlation 0.9163 down to 0.9066 and pixels off by more than 20
rising from 108051 to 162636 -- so the dim's average contribution is
right while its application is not exactly the game's. And separately the
per-tile map shows a +25 to +38 hot spot on the upper-right Z swoosh,
which a capture from the first iteration of this work already showed pink
in the game and white in ours. Same region, still undiagnosed.

docs/re/ui-title-build-map.md

@@ -351,3 +351,54 @@ This follows from the decoded sweeps plus a measurement, and the two agree:
 So the name `loop*.rat` is misleading — in this build the records animate **once**
 during the build-in and then rest off-screen. 🟡 This is about *these* groups on
 *this* screen; nothing here says no group anywhere loops.
+
+## ✅ The title's settled pose is `rest`, and the "washed-out slab" is a MISSING dim
+
+The port agent could not decide whether `rest` or its played-out timeline is the
+title's arrived pose (they disagree by 142–247/255), and separately reported a
+*"washed-out cyan glow slab over the title logo that the running game doesn't
+have"*. The plate-free capture settles both.
+
+`sylpheed-cli screen render --build 4 --black`, edge-correlated against
+[`live-title-build4-no-plate.png`](captures/title-builds/live-title-build4-no-plate.png)
+— a capture of the real screen, so this is an independent oracle and not one
+renderer checking another:
+
+> **0.9163 at shift (0,0)**, and per band 0.92 / 0.78 / 0.93.
+
+**Geometry is right**, so `rest` is the arrived pose for the title.
+
+### The slab is the 25 % dim, absent — not a glow, present
+
+`rest` alone is **uniformly too bright**, and the excess leans cyan:
+
+| render | mean (render − capture) | R | G | B |
+|---|---|---|---|---|
+| `--black` | **+13.14** | +12.35 | +13.58 | +13.48 |
+| `--black --primitives` | **+0.55** | +1.30 | +0.89 | −0.54 |
+
+Drawing the `.prm` primitives collapses the excess to nothing. The element is
+**`pteff02.prm`**, the 25 % dim quad (build 4, rest at `t=46`, fade `0x40` = 64 =
+25 %) — and `--primitives` is **off by default**.
+
+So the "washed-out cyan slab" is not something being drawn that shouldn't be. It
+is the **dim that should be drawn and isn't**: without it every pixel sits ~13
+high, and because the title art is blue-dominant the shortfall reads as a cyan
+wash. ⚠️ Any consumer of `screen render` that omits `--primitives` on this screen
+gets it.
+
+### 🟡 The residual: right on average, not right per pixel
+
+With primitives the *mean* is essentially exact (+0.55) but pixel agreement is
+slightly **worse** — edge-correlation 0.9163 → **0.9066**, and pixels differing by
+> 20 rise 108 051 → 162 636. So the dim's average contribution is right while its
+application is not exactly the game's (blend mode or per-region alpha). Not
+diagnosed.
+
+### 🟡 And a second, localised excess
+
+The per-tile map shows a hot spot in the **upper right** — tiles at
+x ≈ 800–1279, y ≈ 112–225 run **+24.8 / +37.8 / +33.3** against ~+12 elsewhere.
+That is where the title's `Z` swoosh sits, which a capture from the first
+iteration of this work already showed **pink-tinted in the game and white in our
+render**. Same region, still undiagnosed.