Here’s a cute little snippet for automatically transmogrifying your OpenGL textures into iPhone-acceptable dimensions at runtime if you don’t want to go to the trouble of sorting out the source assets, because maybe you’re porting existing assets from another platform, or your artists can’t follow directions, or whatever:
First off, figure out power-of-two dimensions:
You could figure that out on your own no doubt, but you might miss this; if it turns out that the image is too big, your friend CGAffineTransform can sort that out for you!
That’s quicker than going through and canonizing a large asset base yourself, indeed. Read the rest of the article for further explanation; and this is part of the D’Jinn Engine for the iPhone which can be found on Google Code. Enjoy!