SiS:
Neat. What I thought might be a hardware limitation (~1.5 bit error with 32-bit depth buffer in glean's readPixSanity test) has its root in Mesa casting the depthbuffer clear value, a double, to a float then back to a double. Submitted a patch for it. Cleaned up the fog code greatly by removing choosing the CHEAP fog mode which wasn't cheaper and was actually uglier. Nearly fixed the glean maskedClear test, but for the doublebuffered context case the back buffer clearing sometimes doesn't work right, and the bug seems to rely on the state of the hardware before the running of glean. Fun.