Resolved the "colours look odd" channel-order/sRGB question for k_8_8_8_8
(T8aD 2D UI textures) with no emulator run:
- sRGB: Canary's Vulkan host-format table maps plain k_8_8_8_8 to
R8G8B8A8_UNORM and contains no R8G8B8A8_SRGB anywhere — gamma is a
separate explicit EDRAM path. So these are raw linear bytes; apply no
sRGB/gamma decode.
- Channel order: measured 789 real disc textures — byte0 is the opaque
alpha (==0xFF-dominant) in 97% — so on-disk is ARGB. Cross-checked
against xenia-rs decode_k8888_tiled, the Canary-validated M1/M2 path,
which nets the same [A,R,G,B]->[R,G,B,A]. sylpheed-formats is correct.
Promotes the k8888 entry HYPOTHESIS -> CONFIRMED; INDEX updated. XPR2
skybox tiling + viewer display-gamma remain separate open items.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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