Graphical issues for GtKGL in software rendering

The issue has been fixed in GTK since 20.10

Hello Sebastien, or anyone else affected,

Accepted gtk+3.0 into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/gtk+3.0/3.24.20-0ubuntu1.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-focal to verification-done-focal. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-focal. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

Hi all. The conditions for reproducing the issue: CSD + OpenGL + swrast.

Notice that the GTK GL example doesn't use CSD i.e. it doesn't set a custom GtkWindow titlebar. I have attached a small test case that reproduces the issue.

I can confirm that libgtk-3-0 3.24.20-0ubuntu1.1 from focal-proposed fixes the rendering issue.

I have tested with:

1) the attached minimal test case:

gcc -o testcase testcase.c `pkg-config --cflags --libs gtk+-3.0`
./testcase

2) a full-blown flutter app:

snap install --classic flutter
flutter config --enable-linux-desktop
flutter create test_app
cd test_app
flutter run

All autopkgtests for the newly accepted gtk+3.0 (3.24.20-0ubuntu1.1) for focal have finished running.
The following regressions have been reported in tests triggered by the package:

aptdaemon/1.1.1+bzr982-0ubuntu32.3 (arm64)

Please visit the excuses page listed below and investigate the failures, proceeding afterwards as per the StableReleaseUpdates policy regarding autopkgtest regressions [1].

https://people.canonical.com/~ubuntu-archive/proposed-migration/focal/update_excuses.html#gtk+3.0

[1] https://wiki.ubuntu.com/StableReleaseUpdates#Autopkgtest_Regressions

Thank you!

The aptdaemon autopkgtest is flaky which isnt due to this update so that should be ignored

The verification of the Stable Release Update for gtk+3.0 has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

This bug was fixed in the package gtk+3.0 - 3.24.20-0ubuntu1.1

---------------
gtk+3.0 (3.24.20-0ubuntu1.1) focal; urgency=medium

  * debian/patches/git_rendering_issues.patch:
    - cherry pick an upstream fix for opengl display issues when using
      software rendering (lp: #1960947)
  * debian/patches/git_newglib_symbols.patch:
    - backport patch to fix the build with the current libglib version

 -- Sebastien Bacher <email address hidden> Tue, 15 Feb 2022 18:50:52 +0100