Bug 230619

Summary: WebGL premultiplied: false is composited as premultiplied
Product: WebKit Reporter: Kimmo Kinnunen <kkinnunen>
Component: WebGLAssignee: Kimmo Kinnunen <kkinnunen>
Status: RESOLVED DUPLICATE    
Severity: Normal CC: dino, gman, kbr, kkinnunen, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Local Build   
Hardware: Unspecified   
OS: Unspecified   
See Also: https://bugs.webkit.org/show_bug.cgi?id=230613
Bug Depends on:    
Bug Blocks: 230620    

Description Kimmo Kinnunen 2021-09-22 06:14:52 PDT 
WebGL premultiplied: false is composited as premultiplied

Colors seem to be wrong
Comment 1 Kenneth Russell 2021-09-22 16:31:21 PDT 
In Chromium it was necessary to maintain a separate texture for the WebGL rendering results in {premultipliedAlpha:false} mode, and perform a blit at the end to get them into premultiplied mode for compositing.

In case it's useful, please search for "premultiplied_alpha_false_texture_" in:
https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/platform/graphics/gpu/drawing_buffer.cc
Comment 2 Radar WebKit Bug Importer 2021-09-29 06:15:14 PDT 
<rdar://problem/83668315>
Comment 3 Gregg Tavares 2022-04-16 19:41:56 PDT 
same as this issue?

https://bugs.webkit.org/show_bug.cgi?id=200026
Comment 4 Kimmo Kinnunen 2022-04-22 00:23:55 PDT 

*** This bug has been marked as a duplicate of bug 200026 ***