I'm drawing a sphere with two clipping planes. On nvidia graphic cards everything works fine, the sphere is drawn and also clipped correctly.
But on a different system using an Intel onboard graphic adapter the whole clipping goes terribly wrong. But only if both clipping planes are enabled. Using only one plane, regardless which one of them, the sphere is drawn correctly.
I've already checked GL_MAX_CLIP_PLANES but the guaranteed six planes are supported.
Any idea what's the problem here? A driver bug?