Back-buffer as a texture?

Hi!
Do you know a way of using a backbuffer where I can render, and after can use this back buffer as a texture. I’m using OpenGL.
Thanks.

Check out glCopyTexSubImage2d.
Also, check out pbuffers.

Hi!
Yes now I’m using Pbuffer and render_texture extensions. But the speed is really low. Can you tell me why and if can I do something to speed it up.
Thx.