There are multiple types of swizzling here.  It's a bit confusing.

Swizzling A: Swapping rgba channels.  The game can "remap" them just as GL allows us too, and this is handled by the GetRemap() stuff.
Swizzling B: To put things into the right channels, we have to swizzle it, e.g. tell GL to put GL_ONE in one of the channels.
Swizzling C: The actual pixels of the texture may be organized non-linearly.  In other words, they might be in blocks (the PSP has this feature too, I think it's slightly different, though.)

The `if (is_swizzled)` check here is for type C.  In actuality, the other types probably need it too.  There's simply no test for them yet.

-[Unknown]