The port asked whether the refined sweep fit t=357.7 was measured against
live-title-build4-no-plate.png, because if so one of us is 42 units out.
It was not. 357.7 was solved against title-draw-capture-vertex-colours.log, a
GPU per-draw capture of the submitted vertex buffer -- four observables at once,
two quad centres and two vertex alphas. No framebuffer, no PNG.
The gap is not a fitting error either. Posing the leaves directly, t=400 misses
the captured quads by +169.0 and -172.2 px. Probe control: it reproduces the
page's published t=355 centres, 981 and 478, exactly.
Refutation attempted and FAILED: I expected the port's fit to be minimised by
the quad leaving the screen -- 'best fit' meaning 'draws least', the same shape
as the .tbm control that could not fail. At t=400 quad B is fully on screen and
quad A is 319 of 400 px. Their number is fitting something present and it
survives.
The real reason the two must differ is better than 'different frames'. The
sweeps are nested records on a free-running loop and their cycles differ -- 600
and 720, read from the record header +0x08 -- while the top-level clock stops at
settle. So two captures of the same settled title share a screen time and not a
sweep phase, by construction.
Consequence for the port: a sweep position does not date a frame; it gives a
phase on a 600- or 720-unit loop. And 357.7 is a joint fit over both leaves
while the port's ~400 poses one, so the two are not comparable in kind -- the
phases coincide only every LCM 3 600 units.
Discriminator handed to the port rather than taken: if its ~400 is pteff03 and
the frame is in the first cycle, pteff03a must be at centre 295 in that same
frame. The fit is against its renderer, so it owns the check.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Wuu56cE8vJGTBtn1ppsk8v
a4b8397d43