From what I've seen, when using D3DXCreateTexture with sprites that aren't properly sized (2^x) everything is automatically taken care of. When displaying them as sprites with ID3DXSprite they are shown in proper size.

But this takes some time to load if you have a lot of sprites. Especially if you want to generate mipmaps and apply texture compression on top of it. Obviously it's a lot faster to load .DDS data, if you've already applied the texture compression and pregenerated the mipmaps. This sounds like a nice alternative, but this format doesn't seem to support sprites of arbitrary sizes (when using compression)?

I'm thinking that maybe you can get around this by stretching the sprites, and then specifying another height/width manually through D3DXCreateTextureEx or so, but how can I guarantee that my stretching is done the same way that ID3DXSprite do the shrinking? Without distorting the sprites? Or can I just fill out my sprites to the right/bottom with black borders/zero alpha or something?