Hi
In Facing issue with the OpenGL visualization software for GEANT4. - #7 by mritunjay the problem was solved by re-installing X11. Did you try that?
It’s also good to check that you have an up-to-date driver for your graphics card.
If you have built with
you should be able to
/vis/open OGLSX
which will open an X11 window outside the Qt GUI.
Let us know how you get on.
John