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View Full Version : FBO switching or switching FBO bindings



FlipFlop
08-14-2005, 03:30 AM
I'm doing some mulitpass experiments and i need to save some of the earlier stages for later stages.

To begin with i had 2 FBO's set up with bindings to different textures. I would then ping pong between these alternating input and output.

Now i just have one FBO and bind the textures i want as i move through the stages. Seems to be working just as well, but i was wondering if theres any well informed people around that knows if this is good/bad/equivalent compared to setting up all the binding combinations you need in FBOs and then bind those instead.

Jay Cornwall
08-14-2005, 11:34 PM
I haven't personally tested the single/multiple FBO approach, but the impression I get from other's experience is that using a single FBO with multiple attachments is faster.

I can confirm that by not switching the FBO bindings at all you can get a small performance boost again. Bind all your textures first and use glDrawBuffers to switch between them; you can still write to a bound texture as long as it hasn't been selected with glDrawBuffers.