fill_quad composites an untextured primitive as a solid rectangle of the
keyframes fade colour, pivot x 2 in size, placed and scaled exactly as a sprite
is. Behind ComposeOptions::include_primitives and screen render --primitives.
On the title screen, whose paint order is ground truth, it is measurably right:
mean luminance 76.30 -> 63.72 against the captures 64.58, i.e. from +18% to
-1.3%, and mean absolute difference 16.07 -> 13.08. The background was ~40% too
bright; pteff02.prm, a 25% black dim, was what was missing. The wordmark is not
dimmed by it because the measured order paints that quad at slot 4, beneath the
logo. Edge correlation moves 0.9538 -> 0.9480, which is not informative here: a
uniform dim scales gradients uniformly so a normalised edge score barely sees it.
OFF BY DEFAULT, and that is the finding. A primitive has no T8aD header, so no
layer key, and derived_paint_order sorts the keyless to the end. GP_DIALOGs
pzeff00.prm is a single keyframe of opaque black at full screen; painted last it
wipes the build. Of the 125 builds that draw a visible primitive, 36 come out
>99% one colour with the derived order.
No constant default works, because the two screens read off the running game
disagree: the splash paints its primitive FIRST (the black backdrop) while the
title paints one at slot 4 and another LAST (the fade-out). Declaration order
fails the title too. A disc test measures the damage rather than asserting the
feature works, so the number moves when the ordering is solved.
Also records a false alarm worth keeping: a first pass reported 36 GP_DIALOG
builds at "100% black", which was a crude near-black pixel threshold and not a
black screen - those dialogs are dimmed 50% and perfectly legible. The genuinely
wiped builds are a different set.
369 .prm elements exist in the disc's screen builds and every composite is
missing them. Swept statically:
* none of the 369 has a RATC child of its own name — no payload, nothing to
draw, so .prm is a primitive and not a sprite;
* kind & 0x10 and a .prm name agree with ZERO exceptions in either direction
over all 965 builds, so the format marks primitives as a decoded field and a
port need not parse filenames;
* 361 of 369 are exactly 1280x720 at scale 100% in the corner, and their
keyframe 'fade' ARGB is overwhelmingly black at some alpha — these are the
fade-to-black, dim-behind-menu and flash layers, i.e. the PRMD dim-quad the
compositor's backdrop has been standing in for.
Refuted before believing: drawing them at Element::rest() is wrong. The title's
pteff00.prm is opaque -> transparent -> transparent -> opaque, a transition whose
resting pose is the transparent plateau; rest() picks by longest dwell and lands
on the opaque endpoint, which is painted LAST on that screen and would black out
the title. A test asserts that wrong answer deliberately so that fixing the
resting rule fails it and leads to the note.
No compositing change: the resting rule is not .prm-specific and has to be A/B'd
against the title framebuffer capture first.
