Is it possible to use color pallettes in openGL ES 1.1?
I'm currently developing a game which has player sprites, and the player sprites need to be able to be changed to different teams' colors. For example, changing the shirts' colors but not the face colors, which rules out simple hue rotation.
Is this possible, or will this have to be implemented manually (modifying the texture data directly)?
It's not a hardware feature of the MBX but a quick check of gl.h for ES 1.x from the iPhone SDK reveals that GL_PALETTE4_RGB8_OES, GL_PALETTE8_RGBA8_OES and a bunch of others are available as one of the constants to pass to glCompressedTexImage2D, as per the man page here. So you can pass textures with palettes to that, but I'll bet anything that the driver will just turn them into RGB textures on the CPU and then upload them to the GPU. I don't believe Apple support those types of compressed texture for any reason other than that they're part of the ES 1.x spec.
On ES 2.x you're free to do whatever you want. You could easily upload the palette as one texture (with, say, the pixel at (x, 0) being the colour for palette index x) and the paletted texture as another. You'll then utilise two texture units to do the job that one probably could do when plotting fragments, so use your own judgment as to whether you can afford that.