Is it possible to directly copy the contents of one texture directly to the contents of another texture?
(Ie. what I really want to do is clone an existing texture without destroying(overriding) the frame buffer, creating a P-buffer or stalling the pipeline by reading the texture back into main memory)
Do the “glCopyTexImage*” and “glCopyTexSubImage*” calls do what you need?
Blue book. Required reading.
No, those won’t copy from texture to texture.
I think the best way is to just save the texture in system memory and re-upload it when needed. If you can’t do that, you’ll have to render the texture to a buffer and use glCopyTexSubImage2D() to copy it into a new texture.