Bug 244727

Summary:	[GStreamer] DMABuf sink mis-renders frames in XvFB
Product:	WebKit	Reporter:	Alicia Boya García <aboya>
Component:	WebKitGTK	Assignee:	Nobody <webkit-unassigned>
Status:	RESOLVED WORKSFORME
Severity:	Normal	CC:	bugs-noreply, philn
Priority:	P2
Version:	WebKit Nightly Build
Hardware:	Unspecified
OS:	Unspecified

Description Alicia Boya García 2022-09-02 14:07:01 PDT

While debugging https://github.com/WebKit/WebKit/pull/3802#issuecomment-1232898953 I found out that video elements don't render any image inside LayoutTests.

This is particularly problematic for any tests relying on visual output, such as reftests.

This is easily reproduced with compositing/video/video-border-radius-clipping.html, which should output a single big green frame -- and does so in the minibrowser -- but appears white when ran in the test runner, for instance, in this EWS results: https://ews-build.s3-us-west-2.amazonaws.com/GTK-WK2-Tests-EWS/dbb1766c-24083/results.html

Passing --wrapper='env GST_DEBUG=webkit*:DEBUG' to run-webkit-tests shows the likely culprit of this, a failure to get a GL context:

0:00:03.530073170    56       0x7f6ac0 WARN       webkitmediaplayer PlatformDisplayGStreamer.cpp:115:tryEnsureGstGLContext: Failed to fill in GStreamer context: could not retrieve fbconfig from its ID 0x42. Wrong Display or Screen?

Comment 1 Philippe Normand 2022-09-25 09:35:08 PDT

compositing/video/video-border-radius-clipping.html is passing though? At least here in the default XvFB setup and also when I pass --display-server=wayland

Comment 2 Philippe Normand 2023-03-23 04:55:32 PDT

The GL sink is now replaced by another sink, re-titling the bug. I can now reproduce this issue here, the actual rendered frame is white instead of green. Zan mentioned this could be a TextureMapper bug. To be confirmed.

Comment 3 Philippe Normand 2023-04-21 09:13:00 PDT

Seems like this was fixed... compositing/video/video-border-radius-clipping.html is passing in XvFB and host wayland compositor.