is it possible to allow the glCopyPixels() to copy pixels between textures and the framebuffer? it should not have a problem if the textures are resident.
The right way to do this is almost certainly drawing a textured quad that renders the desired texels into the framebuffer.
-texture to framebuffer: draw a quad.
-framebuffer to texture: glCopyTexImage,glCopyTexSubImage (this functions are not optimized in all hardware implementations, but in my GeForce2 the work really fast).
Anyway, this is not a suggestion to future opengl releases. A valid suggestion in this direction would be to have hardware rendering to offscreen buffers or to textures directly (without having to draw to the frame buffer first). This would be a very powerfull new toy for us.
[This message has been edited by coco (edited 01-07-2001).]