   On the fly DXT5 compression
  Is it possible to load an uncompressed texture then have the driver compress it for me by specifying the internal format as a compressed format?   
  yes but its not superfasta good method if u plan to use the same textures is to upload the uncompressed texture and compress it with the gl and then ask for the texture back from gl (which u can then save on disk)and in future just load that   ;  ah, now that's a good idea indeed. Thanks for the tip! rating++.   ;  You can also use a tool such as ATI's compressonator to compress the images to DXTn format offline and then load them in.   