[Webkit-unassigned] [Bug 238022] New: WebGl incorrect rendering on 15.4 using Playcanvas

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=238022

            Bug ID: 238022
           Summary: WebGl incorrect rendering on 15.4 using Playcanvas
           Product: WebKit
           Version: Safari 15
          Hardware: All
                OS: iOS 15
            Status: NEW
          Severity: Major
          Priority: P2
         Component: WebGL
          Assignee: webkit-unassigned at lists.webkit.org
          Reporter: mvaligursky at snap.com
                CC: dino at apple.com, kbr at google.com, kkinnunen at apple.com

WebGl rendering on 15.4 has some major problems using Playcanvas engine. This has not been the case on 15.3.

Repro steps:   https://playcanvas.github.io/#/graphics/area-picker

also these additional examples (available on the same url) have similar problems, some don't render at all:
- all anim blend trees + few more anim ones
- area picker
- clustered area lights
- grab pass
- post effects

tested on iphone XR 15.4 and also on Safari 15.4 Mac OS. Both WebGl1 and WebGl2.

A possible workaround seems to be disabling of antialiasing (which means passing { antialias: false } to canvas.getContext as an option when initializing WebGl.
Most of these examples do some form of rendering to texture and then using the results, but other examples using rendering to texture seems fine.

our tracking ticket: https://github.com/playcanvas/engine/issues/4136

Possibly related to:
https://bugs.webkit.org/show_bug.cgi?id=237906
https://bugs.webkit.org/show_bug.cgi?id=237006

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-unassigned/attachments/20220317/8e13c317/attachment.htm>