Report QML visual glitch (Large orange triangles) to R&D

[keithel-qt]

On some lower end machines, visual glitches show when running swift toolbox. It manifests itself as orange triangles that show for a single frame or so (so, hard to see) that repeat on the order of single seconds.

[keithel-qt]

[keithel-qt]

@john-michaelburke Could you or Jason run the qtdiag tool on one of the affected machines?
We think we found a similar bug and want to correlate.

You can find the tool in a PySide2 installation right under the PySide2 module directory (.../site-packages/PySide2/qtdiag)

[john-michaelburke]

@silverjam was this on your PC or one in the lab?

[silverjam]

@john-michaelburke This happens on my machine, but not very often (though it does happen more when I'm running Zoom). The video here is from Stefan's new Windows 10 laptop where it happens very frequently and starts to impact the usability of the app.

[john-michaelburke]

I'll try and build a test release with the work around you mentioned:

Workaround:
Prior to the creation of QApplication set the following environment variable:
QSG_RHI=1

And get it to Stefan to see if that fixes it.

[keithel-qt]

This is possibly QTBUG-69538

It is inherently fixed in Qt6, and there is now a patch for it in Qt 5.15.11 (commercial only).
We can probably get Qt Releasing to spin another set of wheels with the patch, however I think there's another fix for it that could be tried that shouldn't slow down rendering:
Workaround:
Prior to the creation of QApplication set the following environment variable:
QSG_RHI=1

[keithel-qt]

Note to myself - The Qt Internal discussion on this topic (should only work for me)

[keithel-qt]

Sounded from J-M today that he heard back that the glitches may be fixed with the QSG_RHI=1 workaround.
More testing probably needed though.

[silverjam]

@keithel-qt @adrian-kong @john-michaelburke This relates to our discussion yesterday, since this tearing bug is fixed in Qt6 then we probably can revert the explicit QSG_RHI stuff

[silverjam]

Will check with Stefan if bug is fixed for him in 4.1 without the QSG_RHI var set here: #815

[silverjam]

Tag here: https://github.com/swift-nav/swift-toolbox/releases/tag/v4.1.4-no-qsgrhi