eb86142e4f
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.