My opinion of UT and OpenGL vs D3Dis mixed. In a nutshell, the game seems to be slightly smoother in OpenGL, but it looks somewhat better under D3D.
There are more graphics glitches under OpenGL than under D3D. Though they generally aren't as bad as the worst of the D3D glitches, there are more of them. I've noticed several skyboxes that look great under D3D look like S-H-I-T under OpenGL. That seems to be a lighting thing. In fact, lighting everywhere looks different under OpenGL, brightness and contrast levels seem to be handled very differently. Also under OpenGL parts of a map's architechture, such as pillars, beams and other trim, often dissappear depending on the angle of view. On the other hand, there seem to be fewer big, ugly HOMs than under D3D. I'm guessing those dissappearing pillars and beams might show up as small, barely noticeable BSP errors under D3D. Average framerates are a touch lower in OpenGL, however the lows are somewhat higher and of shorter duration than in D3D, so OpenGL feels a little bit smoother.
Which one is better is pretty much a tossup for me. I still use D3D, mainly because I think it looks better and I'm used to that look. Hehe besides that, the skybox in one of -MY- maps is one of the ones that looks like S-H-I-T under OpenGL. I'm sure if the maps, including mine, had been designed under OpenGL in the first place, they would look a lot better under it, however, then they wouldn't look as good under D3D.
And yes, I have the latest OpenGL drivers off Epic's UT technical page and I updated the ini file too.
