Working with QGLWidget.
After hours spent at looking for the reason, why QPainter can draw pixels, lines and polygons, but cannot draw text, i copied 1:1 the example project "Sample buffers", ran it, only to see that it is not working either.
The issue applies to both QPainter painting on a QGLWidget and native OpenGL painting on a QGLWidget. Both can paint virtually anything without errors, but not text.
In the example project, when I comment out
//renderText(-0.35, 0.4, 0.0, "Multisampling enabled");
//renderText(0.15, 0.4, 0.0, "Multisampling disabled");
//renderText(-0.35, 0.4, 0.0, "Multisampling enabled");
//renderText(0.15, 0.4, 0.0, "Multisampling disabled");
To copy to clipboard, switch view to plain text mode
it works nice and I can see the image which I should see, without the text, of course. And the program closes normal...
But when these lines are not commented out, I see a empty, plain white window without any drawing. And when I close the program, it throws a segfault.
When using functions for text drawing, I get on the debug console three times "getProcAddress: Unable to resolve 'glProgramParameteri' ". Both in the example and in my own program.
Is this a hardware/driver issue or is something wrong with Qt?
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