67fa1a1b0b
The rotated quads on the title screen come from the keyframe block after all. The earlier negative -- "every GP_TITLE build 4 element has all three angle words at zero" -- read the right bytes over too small a region: it walked the top-level declaration table, and the rotated elements are the nested leaf records ptloop01.rat / ptloop02.rat. Confirmed against the framebuffer rather than against our own renderer. The two records declare +12 = 30 and -45; the GPU capture submits their quads at +30.26 and -45.28 degrees -- magnitude and sign, two different values. Corroborated by shape in GP_BUNK 117ca14f, where +12 ramps 0 -> 360 with position, scale and alpha constant: a spin in place. Identifying which draw it was needed edge lengths, not bounding boxes: 400x1076 and 400x1444 against pteff03/pteff03a 399x180 at the elements' two different declared scales, 600% (1080) and 800% (1440). The same test names three known-positives in the capture (ptlogo1, ptcopyright, ptbtn00), so it passes its own control. Keyframe gains rotation_deg plus unknown_4/unknown_8, carried rather than dropped. NOT rendered -- ui_layout::blit is axis-aligned only, so the reference renderer and the port will both draw these upright until a rotating blit exists. The census tool ships with the trap that broke its first version: nested RATC blobs are not 4-byte aligned, so an aligned scan found 0/3 of its own control blocks and missed 16 341 blocks. Disc-wide +12 is non-zero in 14.50 % of 83 862 blocks. sylpheed-formats tests, SYLPHEED_DISC set: 131 passed, 0 failed across the 6 suites finished at commit time; the run had not yet completed.