How can I read back values from an FBO that only has a depth attachment (with glDrawBuffer set to GL_NONE)?
It appears that a glReadBuffer of GL_DEPTH_ATTACHMENT_EXT is not legal. Nor does it work on my implementation. Do I have to attach a color renderbuffer just to get at the depth values?
Sorry. For apparently no reason at all other than a forced (Java) rebuild, it just started working with glReadBuffer set to GL_NONE. I’m still not sure if this is behavior I should rely on. Your thoughts appreciated.
Thanks. The glReadBuffer man page won’t have GL_NONE because the usage is defined in the FBO extension. With my NVidia Quadro FX 360M/PCI/SSE2, I need the call or else the readPixels doesn’t work at all.