hi to all! ( post #1 for me… )
I have a problem described by this code: external link
It is related to massive issue of occlusion queries when rendering to an FBO. (WindowsXP/Vista/32bit/NVidia)
I tested this code on some NVidia GeForce and Quadro.
The problem arose with new chipsets, while in older ones it was not a problem.
If i have - say - 100.000 points per cycle, and i perform an occlusion query for each of them, i can do at last 9 cycles before death. With “death” i mean
<< Unhandled Exception at 0x69592001 in test.exe: 0xC0000005:
Access violation in writing [snip] 0x695e76f0 >>
which seems to be inside NVidia driver.
my debugger shows the IP to point to a random OpenGL call (maybe the first after the problem ).
If i perform the same queries without FBO all runs perfectly, if i draw the same points to FBO without queries all runs perfectly.
Since the problem occours only performin many queries (e.g. a million), could it be related to state deletion of query objects?
In the code linked above, i reproduced the problem in the simpler case. I borrowed FBO code from an Nvidia example, and the GLUT structure from NeHe tutorials.
The occlusion query code is quite the same as the one in the ARB specification, except that i massively use vector constructor/destructor of query objects.
If this is not an NVidia bug, i am doing something wrong.
hoping to be useful,
thanks for your time