One unit, per the new PROTOCOL section. Question, look-at, and
not-covered written before the work.
pteff03 and pteff03a -- the sweep parents behind ptloop01/ptloop02 --
declare 0:a=0 70:a=0 100:a=255 238:a=255 250:a=0. So they rise 70->100 and
fall 238->250. The brief's own warning was right: 238..250 is a fade-out,
the same shape ptcopyright uses, and ptcopyright starts nothing.
The sweep is declared visible from t=100, which is 136 units BEFORE the
plate reaches full alpha at 236, and is fading out by 238.
That contradicts the human's report that the sweep only starts when the
plate appears -- and the reason both can be true is the next unit.
ptloop01/ptloop02 are .rat leaves whose own timeline is a TRANSLATION:
ptloop01 runs x = -639 -> 1521 over a 600-unit loop, so at its own t=0 the
sweep sits off the left edge of a 1280-wide screen. The parent's alpha says
"drawn"; the leaf's position says "where". A quad can be fully opaque and
entirely off-screen.
Explicitly not actionable alone: this says 238 is not a start. It does not
say the port should show the sweep from t=100, because if the leaf is
off-screen there then both renderers can be correct on alpha and differ
entirely in what is visible.
Refutation of the brief's own lead that "236-238 is a synchronisation point
and a human reported a behaviour change there": the synchronisation is
real -- pteff02 at 236, ptlogo_back2eff and ptcopyright at 238 -- but the
reading is refuted. For the sweep it is where things END. A cluster of
keyframes marks a moment; it does not say which direction anything moves
through it.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jc4pciRArGHfxGGhEbwp5t
f2d3f35cb9