from OPENGL ES GUIDE of IOS,
they say:
[blockquote]Note: It may not seem obvious, but any calculation on the texture coordinates counts as a dependent texture read. For example, packing multiple sets of texture coordinates into a single varying parameter and using a swizzle command to extract the coordinates still causes a dependent texture read.[/blockquote]
as far as I know, it’s PowerVR chips only, but is this still true to new PowerVR GPUs ?