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+# The splash: frozen, then fixed, and now checked for SHAPE as well as motion
+
+**Status:** ✅ **animates, and the ramp matches the declared curve.** Written
+2026-09-02 by the Port; HANDOFF on this branch answers `9ca1eb5`.
+
+The 2026-09-02 play-test found the splash frozen. The cause and the fix are in
+the commit history; this page is the part that comes after — **is the animation
+now the right animation?** `motion-census` says explicitly that it cannot answer
+that: *"a wrong ramp that moves every frame passes here."*
+
+## Pre-registered (R2)
+
+`palogo_sqex_eff` declares `0:a=0 → 15:a=255 → 30:a=212 → 45:a=0` — three
+segments, three gradients:
+
+| segment | declared |
+|---|---|
+| 0 → 15 | **+17.0** per unit |
+| 15 → 30 | **−2.87** per unit |
+| 30 → 45 | **−14.13** per unit |
+
+> So a film should show three straight runs with breakpoints at **15** and
+> **30**, the middle slope about **1/5** the magnitude of the last, and the rise
+> about **1.2×** the last.
+
+## Measured, from a film of a real boot
+
+Region: `686x11+299+319` — the companion's top strip, which **no other element
+overlaps**, so the number is that element's own alpha and not a composite.
+
+| view units | strip mean | slope/unit |
+|---|---|---|
+| 5.58 | 0.02809 | |
+| 10.00 | 0.05086 | **+0.00515** |
+| 13.04 | 0.06611 | **+0.00503** |
+| 16.12 | 0.07530 | +0.00298 ← crossing the breakpoint |
+| 19.21 | 0.07260 | **−0.00087** |
+| 25.38 | 0.06695 | **−0.00092** |
+| 28.39 | 0.06482 | −0.00071 |
+| 31.39 | 0.05719 | −0.00254 ← crossing the breakpoint |
+| 34.39 | 0.04471 | **−0.00416** |
+| 40.39 | 0.01910 | **−0.00428** |
+| 43.39 | 0.00655 | −0.00418 |
+| 46.39 | 0.00000 | gone |
+
+**Breakpoints land where declared**: the rise stops between 13.0 and 16.1, the
+gentle fall steepens between 28.4 and 31.4.
+
+| ratio | declared | measured |
+|---|---|---|
+| middle : last | 0.203 | **0.213** |
+| rise : last | 1.20 | **1.20** |
+
+Within 5 % and exact respectively. **The port interpolates piecewise-linearly
+across the declared segments** — which is what the Decoder independently measured
+the game doing (28 distinct alphas over 28 consecutive presents, modal steps −3
+and −14 against predicted −2.87 and −14.13).
+
+⚠️ **Ratios, not absolutes, and deliberately.** The strip mean is an alpha
+scaled by whatever the sprite's own pixels are; its absolute value carries the
+texture. A ratio between segments divides that out, which is why the shape is
+checkable from a composite at all. Anyone quoting 0.00515 as an alpha is
+misreading it.
+
+## What this still does not establish
+
+* That it **looks** right. Three instruments have now agreed with a picture a
+  human called wrong, and the fourth agreeing does not change the standing of
+  the fifth. A play-test is the check.
+* Anything about the **developer** splash's three logo/companion pairs. One
+  element, one screen.
+* The **absolute** alpha. The shape matches; whether the port's alpha equals the
+  game's at a given unit is `verify-capture`'s question, and it answers 0.01 %
+  at the settled pose only.