The shared blit shader clamps the sampled Y to flags.z..w, but the
native readback uniform set flags.w to 0, so every row sampled row 0.
The blit pipeline was also built only for the surface format, while the
readback draws into an RGBA8 texture; on a BGRA surface (the usual
Linux/Vulkan choice) the pipeline and attachment formats disagree, which
release builds no longer catch because Dawn validation is skipped.
Build blit pipelines for RGBA8, BGRA8 and the surface format, and pick
one by destination format. The Quest 1 simple blit path is unchanged.
From upstream patchzyy/Wiicompiled 6f14bde (#244, KartPad batch).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Wg7mB8ogCWmp9GH19Uc82B
* Fix already downloaded toolchain re-use
the following mv command would move $work into $toolchain_dir if the $toolchain_dir folder already existed.
* resolve z-fighting
Claude