The overlay re-stroked the whole finished trail on every paint: about
275 ms at zoom-to-fit on a 392-part plate and over 11 s zoomed in, where
dashed rapids spanned millions of on-screen dashes.
The finished trail is now cached in a bitmap at the current scale, so a
pan or playback frame blits it and draws only the moves since. A wheel
zoom stretches the cached image until the wheel has been still for
150 ms, then redraws it sharp. When the trail would be too large an
image, each paint draws only the moves on screen and clips straight
rapids to the view. Arcs are added as GDI+ arcs instead of 5-degree
polylines.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Plate > Simulate Cutting replays the active plate in cutting order: the
torch traces cuts, rapids and pierces timed like Calculate Cut Time, with
play/pause, scrubbing, 1x-250x speed, step and part/cutout jumps. Parts
the torch has not reached are drawn muted.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ajandClaude Opus 5.5