I have a question. I see there’s two ways to do multitexturing - texture stages and multiple UV sets. Does it make a difference to the frame rate which one you use?

i would think not. There is also a 3rd way through shades. I think the 3 of them will be roughly the same speed.

There’s only one way to do multitexturing, and that’s with multiple texture stages. You need multiple texture stages to specify the multiple different textures, one texture per stage. This is the only way to have more than one texture apply to the same polygon at once.

Once you have multiple texture stages, you can choose whether each texture stage uses the same UV’s, or whether they use different UV’s. That decision has nothing to do with performance; it’s just a question of what you’re trying to do. If the multiple textures have similar mappings, they should use the same UV’s. If they have very different mappings, they should use different UV’s.

You can perform the multitexture calculation within a shader. But you still need a way to feed the multiple different textures into your shader as inputs, and that means–multiple texture stages.