Black widgets on Windows XP 32bit, Qt 5.4.1
Qt example "hellogl2", compiled with Qt 5.4.1 32bit, works fine on Windows 8.1. But on Windows XP some widgets are black, as in this screenshot. Widgets are rendered incorrectly with OpenGL version of Qt, and with ANGLE. I use MSVC 2010 compiler. A similar example from Qt 4.8.6 is working properly. My GPU is GeForce 7600 GS, but I'm pretty sure that the error is not related to the standard opengl32.dll and driver from Nvidia. I have compiled a Mesa3d library for Windows using the llvmpipe driver, implementing software rendering. When I put opengl32.dll from Mesa3d in a folder with the hellogl2 executable file, nothing has changed (I'm sure that the library was loaded, because I noticed decrease in the number of frames per second). In some other examples with OpenGL widgets and windows are also displayed incorrectly (although similar examples with Qt4 work well).
How can I solve this problem? Am I doing something wrong?
I found out that widgets are displayed normally if the system is set to "Classic Style" (like in Windows 98). So, Qt 5 does not support Windows XP themes along with OpenGL render! Or is it a flaw in the example?
I don't know the answer to your question, but perhaps you could subscribe to the Interest mailing list and ask there. Qt engineers are active on that list.