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View Full Version : FBO, multisampling and render to texture



khamoon
10-02-2008, 05:11 AM
I hope this was not discussed before, there are so many topics on multisampling, FBO's etc, I tried to look for the answers I need, but I could not find it... If it was already mentioned earlier, forgive me the redundancy :)

I get "inavalid framebuffer operation" on any drawing command (glClear, glDrawElements, etc.) when I use FBO with multisampling and also have the multisampling forced in the NVidia control panel. The framebuffer is created just fine ("framebuffer complete"), it has a color renderbuffer and depth renderbuffer. The card is GeForce 8600 GTS. When I disable the forcing of multisampling in the driver options it all starts to work without errors. It also works fine on gf6800... Has anyone encountered something like this?

One additional question: am I getting it right, that when I want to render to texture with multisampling, the only solution is to create two framebuffers, one with multisampling rendebuffers, one with renderable texture attached to it, and then perform blit operation? I thought of using just one framebuffer and than using glCopyTexSubImage, but it seems it is forbidden to copy pixels (glCopyTex*, glReadPixels, etc.) from multisampling framebuffers...

LangFox
10-02-2008, 11:51 PM
You can check the example "Simple Framebuffer Object" in nVidia OpenGL SDK 10.