a15e0ad39c
With the layer key and the primitives' implied keys in place, the tie-break - how the game orders elements sharing a key - is all that is left between the derived order and ground truth. Three measured screens now constrain it. On the menu and the splash every tied group comes out in declaration order, which is what the stable sort already gives. The title is the only screen that discriminates, and nothing predicts it: 0x8083 x5 paints eff1, eff2, eff5, eff3, eff4, and 0x80a0 x7 paints logo1 x3, tm, logo2 x3. Refuted: declaration order; RATC child order; first keyframe time (52, 56, 62, 58, 60 - the measured order is not sorted by them); resting keyframe time; resting X or Y (938, 938, 64, 788, 447); and T8aD header words +00, +04, +0c and +10, which are either identical within a group or unsorted. Child order is worth its own line: a strict improvement over declaration order (7 misplaced positions on the title instead of 9, and it recovers the logo grouping) and exactly right on the other two screens. NOT adopted, because on the only screen that can tell them apart it is still wrong. Adds a test that measures what the residual costs instead of assuming it. Of the 3 disagreeing pairs of drawn elements across all three screens, all 3 have overlapping bounding boxes and 2 share opaque pixels: ptlogo_back2eff5 against eff3 (22568 px) and eff4 (32395 px). The third pair, ptlogo2 vs ptlogo_tm, overlaps by two columns and shares NO opaque pixel - the wordmark is transparent there. A bounding-box test called that a defect; reading the alpha says it is not, which is why the test reads pixels. The set is pinned, so a change that makes it worse fails. 15 disc tests green.