314719 2026-05-13 03:16:40 -0700 [WPE][GTK] Atlas textures use spec-violating glTexImage2D(internal=GL_RGBA, format=GL_BGRA), render black on strict GLES drivers 2026-05-21 01:39:11 -0700 1 1 1 Unclassified WebKit New Bugs WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED InRadar P2 Normal --- 315035 1 alex alex commit-queue webkit-bug-importer oldest_to_newest 2210462 0 alex 2026-05-13 03:16:40 -0700 SkiaGPUAtlas allocates BitmapTextures with the UseBGRALayout flag, which is meant to give them BGRA storage. BitmapTexture::allocateTexture() and BitmapTexture::reset() currently call: glTexImage2D(target, 0, GL_RGBA, w, h, 0, textureFormat(), UNSIGNED_BYTE, nullptr); where textureFormat() returns GL_BGRA for UseBGRALayout textures. So the actual call for atlas textures is: glTexImage2D(target, 0, GL_RGBA, w, h, 0, GL_BGRA, UNSIGNED_BYTE, nullptr); This combination is undefined per the EXT_texture_format_BGRA8888 spec, which mandates internalFormat == format == GL_BGRA_EXT: https://registry.khronos.org/OpenGL/extensions/EXT/EXT_texture_format_BGRA8888.txt Driver behaviour observed: * Mesa (Intel/AMD/llvmpipe): permissive — accepts the call. Downstream rendering happens to come out correct because TextureMapper's shaders swizzle BGRA→RGBA at sample time. * Adreno (Pixel 7, Android arm64): strict — rejects every upload with GL_INVALID_OPERATION (0x502). Confirmed by glGetError() instrumentation: 100% of atlas uploads fail. The texture is left in undefined state, and SkImages::BorrowTextureFrom(..., kRGBA_8888_SkColorType, ...) reading from undefined storage renders solid black on subsequent FALLBACK direct-draws. 2210467 1 alex 2026-05-13 03:45:57 -0700 Pull request: https://github.com/WebKit/WebKit/pull/64834 2211632 2 ews-feeder 2026-05-17 23:33:11 -0700 Committed 313395@main (b47541a2e001): <https://commits.webkit.org/313395@main> Reviewed commits have been landed. Closing PR #64834 and removing active labels. 2211633 3 webkit-bug-importer 2026-05-17 23:34:13 -0700 <rdar://problem/177318630> 2211779 4 commit-queue 2026-05-18 12:14:28 -0700 Re-opened since this is blocked by bug 315035 2212075 5 alex 2026-05-19 09:31:01 -0700 Pull request: https://github.com/WebKit/WebKit/pull/65193 2212860 6 ews-feeder 2026-05-21 01:39:09 -0700 Committed 313653@main (1f31db09ec64): <https://commits.webkit.org/313653@main> Reviewed commits have been landed. Closing PR #65193 and removing active labels.