Thanks for all the tips guys...I'll let you know how it goes. Sorry if it seemed like I was blaming Steve for my troubles, no harm was intended. I guess I'll just have to go over the code with a fine-toothed comb of glGetError's until something turns up. > > That shouldn't crash Mesa. I do that all the time in my programs. Or maybe it was his fault after all :-) -W.W.