How to Render Upside down?

how can I render a scene upside down.

another possibility is how can I get glCopyTexSubImage2D to flip it for me.

no, i cant simply adjust the UVs, because that would hose the pbuffer version.


The easiest way to do this is to set your projection matrix with glFrustum(l,r,t,b,n,f) (i.e., with the bottom and top parameters swapped).

Take care, if you’re using face culling, to invert the current glFrontFace() too.

or another way: glScalef(1.0, -1.0, 1.0);
take care of cull face too.