OpenGL / Windows Vista problem

I’m using OpenGL through QT on windows Vista. GDI isn’t used.
However the screen (windowed mode) seems to ignore all GL calls once a drawing is loaded. That is, my background is grey and the cursor which is rendering with GL lines is not visible.
Alt-Tab’ing applications fix this however, everything becomes visible.
I read through few docs about OpenGL on Vista and tried out things. Someone has experience in that or any general hits about Vista/OpenGL?


btw. Does Vista handle 2 monitors as 2 separate back/front buffers?

It may be a problem with Qt, like not passing the refresh events.
Try to force redisplay on the Qt canvas, ie. by sending repaint messages after start ?

About backbuffers, I would say it depends on the card and driver, and on the display mode (pan vs dual-view).

Thanks ZbuffeR.

To the monitor problem:
I have 2 monitors connected and reading pixels from first screen via glCopySubPixels2d() returns pixels that are actually in the backbuffer whereas moving the window to another screen gives me trash data instead. I am using pan view to drag windows from one screen to another. All works fine under XP though. Cant figure out if it’s the code or the model of Vista or … ?

what card and drivers ? you tried more recent ones ?

It’s a Quadro FX 1400. All recent drivers installed. Guess its something with Windows Vista. I actually never did something on Vista before up untill now. So really in the dark here.
Wondering if something might do with glReadBuffer() values other the GL_BACK or GL_FRONT here.

Don’t use front buffer with vista.
Some older articles, but that may help you :

Thanks ZBufferR. I read those already. What you mean by not using front buffers.
I mean why? Im actually always on GL_BACK to read data i once rendered before swapping buffers.

Sorry I misread your previous comment, I though you were reading from GL_FRONT.
No more ideas.