The compositor read a keyframe as `top-left = (X,Y)`, `size = decoded · scale`
and ignored the declared pivot. That is right at 100 %, which is every element
the format was ever checked against — the pause menu, the ARSENAL chip ruler —
and wrong for every element that is scaled.
Measured against a framebuffer capture of Canary on the title screen.
`GP_TITLE.pak` build 7 element 13 is `ptbase2.t32`: 640x360, pivot (320,180),
one keyframe at (320,180) with scale 200 %. From the corner that is a 1280x720
rect at 320..1600 x 180..900 — a quarter-screen slab with the top-left quadrant
bare. Anchored at the pivot it is (0,0)..(1280,720), and the capture shows the
background art reaching all four edges. Normalised cross-correlation of the
composite against the capture, searched over +-40 px, peaks at (0,0): 0.90 on
the planet limb, 0.72 on the lower-left ship.
`ptcopyright.t32` calibrates the other half: unscaled, 694x20 at (293,655), and
the capture's glyph run is x 295..986 / y 700..718 once the 45 px of window
chrome is taken off. So the keyframe really is the top-left at 1:1.
Disc-wide this moves 865 of 5 130 resting placements. The pause menu's own
`pgpeff01` glow stops hanging off the menu frame to the bottom-right and
centres on it.
`ComposeOptions::backdrop` comes with it: the default dim slate stands in for
the PRMD dim-quad behind an in-mission screen, but comparing against a
framebuffer needs the black the game actually composites over, so
`screen render --black` can ask for it.
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