irisandClaude Opus 5
94b1509733
The counters now say which half is left. Re-recording is rare -- 157 row display lists in a minute of scrolling, 407ms in total -- while the frame's draw phase sits at 7.9ms. Since that phase also carries Compose's own measurement, what is left is laying text out: shaping glyphs, on the thread drawing the frame, and none of it timed by anything here. The window moved in one step, so every step boundary shaped two screens of markdown inside a single frame, a page landing did the same, and opening a session did seventeen screens of it in one. It now walks towards its target a couple of rows a frame. That does not make the work cheaper and is not meant to: it stops it arriving together, which is the difference between a frame that is late and a frame that is missed by ten. What is on screen is never amortised. The visible range goes up in the frame it is needed whatever else is pending, and only the margin being read *towards* is spread out -- so this cannot show anybody a gap, which is the failure the last two changes in this area both had. Diagnosis and the ordering from the ai-app-2-6d session, whose test this follows: records small and draw high means shaping rather than recording. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>