Subj : src/doors/syncconquer/DESIGN.md
To   : Git commit to main/sbbs/master
From : Rob Swindell (on Debian Linux)
Date : Mon Jul 13 2026 00:36:58

https://gitlab.synchro.net/main/sbbs/-/commit/a1610a2bae948446be72c7f6
Modified Files:
	src/doors/syncconquer/DESIGN.md
Log Message:
syncconquer: full DESIGN.md Phase-2 dirty-rect spec

Expand the brief Phase-2 note into a proper spec: one transport-agnostic
framebuffer differ feeding a per-tier rect encoder (DrawJXL rects for JXL
clients; a single reused sixel-rect backend for every non-JXL client, since
APC PPM at CTerm 1316 is newer than Sixel at 1189 so PPM implies Sixel);
coalescing + a whole-frame fallback threshold; a cached/sixel background
(never raw PPM) with the C;S/C;L image-cache manager for static UI art;
measured full-frame throughput anchors and a per-scene win table; the
~4% PPM-on-JXL break-even; SF #258 and map-scroll constraints; and a
measurement-probe-first implementation order.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---
 þ Synchronet þ Vertrauen þ Home of Synchronet þ [vert/cvs/bbs].synchro.net

.