An IMAGE whose file exists was drawn as a frame with two diagonals. Now
its pixels are loaded when a drawing opens and drawn on screen and in PNG
output, with rotation, clip boundary, fade and object transparency. A file
that can't be read keeps the crossed-out frame and reports a message.
Ported from the raster commit of #1029 onto the split render and canvas
modules. New here: large images are drawn from a pyramid of levels cut
into tiles uploaded as they come into view, instead of one texture with
pixels skipped, so a large scan stays sharp zoomed in and doesn't shimmer
zoomed out.
Limits are listed in docs/gaps.md (FF10): PDF and SVG output write only
the frame, and on screen images lie under all other objects.
Co-Authored-By: Chanthawat Kiriyadee <enwuft@icloud.com>
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
