On Sun, 2010-11-14 at 20:18 -0800, Dave Airlie wrote: > Eric just checked in a test into piglit that tests that the > gl_FragCoord works the right way up for FBOs, > > Now all the gallium drivers fail this currently and fixing it creates > an ugly linkage between the currently bound buffer and the fragment > shader, since if you swap from an FBO to rendering to the front > buffer, you need recompile the fragment shader to emit a proper wpos > manipulation. Just wondering if anyone sees a nicer way to do this, > than caching frag shaders with some sort of key in the state tracker, > (which is pretty much what 965 has done.).
I guess the other possibility would be to have a couple of constants in the constant buffer which get factored into the fragcood calculation in such a way as to effect a flip based on their value, eg: fc' = fc * const[0].x + const[0].y where const[0] is either -> {1, 0} for non-flipped -> {-1, fb_height} for flipped Keith _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev