Re: [PyOpenGL-Users] Textured polygons disappear on me?!?

[Michael C. <foo...@fo...>]

I'd like to thank everyone for the help, I figured it out and thought 
you guys would want to know what was going on.

Now I "knew" the code was perfect because I lifted it straight out of 
another program of mine that worked fine. Well after trying tons of 
stuff I started to think the problem might be in the loading of the 
texture. While messing around with the call to gluBuild2DMipmaps, I 
noticed that if I passed the wrong number of bytes for internal format, 
while the texture looked wrong things weren't disappearing. It also 
looked like the problem was happening during mipmap transitions (which 
would explain why they seemed to be somewhat depth related). Well after 
messing around with the problem more, I figured out what was going on. 
My PNG which I told to save with transparency, didn't have it. So 
instead of RGBA format, the data was in RGB. The colors were still 
right because it was reading 4 bytes per pixel (so it was skipping the 
nonexistent alpha information). For some reason this only manifested 
it's self in making mipmaps, The other computer I tested this on had a 
software OpenGL renderer that could handle this for some reason (what I 
was doing was wrong, so it's understandable that it wasn't handled 
correctly).

Thanks for all the suggestions. Without some of them (especially the 
depth problem that made me look into mipmaps) I'm not sure I would have 
found this. It explains why previously working code seemed to 
malfunction when it was copy and pasted.

Thanks again guys.