What format do you use? How do you do this? Is there a program that will convert standard image files to some compressed format that I can load directly, instead of wasting time compressing everything at runtime?
Actually, forget that, I don’t want to lose the ability to load a texture at different resolutions. That’s probably why Doom 3 and HL2 load so slowly.
Unless you stored the mipmaps and used the first mipmap for the first lower LOD.
Okay, tell me how.
Take a look at the dds file format (check msdn, it’s a directx file format, but the compressed texture format is used by gl as well).
Also check out
http://oss.sgi.com/projects/ogl-sample/registry/EXT/texture_compression_s3tc.txt
Google for “dds viewer” to find some conversion programs (if you don’t want to roll your own). DevIL supports dds compression as well.