mirror of
https://github.com/crosspoint-reader/crosspoint-reader.git
synced 2026-04-29 10:26:52 -07:00
JustinianandGitHub
825ef56ad8
## Summary Improves text antialiasing quality on the Xteink X3 (SSD1677) display to bring it closer to X4 rendering quality. Addresses white lines through letter strokes and ghosting artifacts during page turns and screen transitions. ## Changes ### Display Driver (open-x4-sdk) - Dedicated X3 grayscale LUTs with tuned VDL drive strengths for dark gray (2 time units) and light gray (3 time units), with active GND hold on non-gray transitions to prevent floating source crosstalk - Tight scan timing: TP2/TP3 reduced to 1 (total gate-on 7 units vs 17), minimizing parasitic charge leakage that caused white lines through letter strokes - Fast diff BB reinforcement: Added mild VDH reinforcing pulse to lut_x3_bb_full so black pixels are actively driven during differential refreshes, clearing gray residue/ghosting - displayGrayBuffer() updated to use the dedicated gray LUT bank instead of full refresh LUTs for X3 ### Rendering Pipeline - Re-enabled light gray rendering for X3 text and images, now safe with dedicated gray LUTs providing proper 4-level gray - Removed isLightGrayRestricted() gating that was limiting X3 to 3-level gray - Runtime display dimensions in DirectPixelWriter and ScreenshotUtil, replaced hardcoded constants with runtime getters to support X3 792x528 resolution ### Note The open-x4-sdk submodule references a commit on juicecultus/community-sdk. A corresponding PR to open-x4-epaper/community-sdk should be merged first so the submodule ref resolves on upstream. ## Testing Tested on physical X3 hardware. White lines through letters significantly reduced, in-book ghosting improved via BB reinforcement, antialiasing visually closer to X4 quality. ## AI Disclosure Yes, AI was used to assist with the development of these changes. ---------