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Furrage
03-15-2002, 09:13 PM
Is there any way to force OpenGL to use page flipping to swap buffers instead of copying the back buffer to the front? As a matter of fact. Is there any way to test if a card supports page flipping?

zeckensack
03-16-2002, 04:53 AM
There may be a switch in your display properties screen (assuming Windows again) where you can enable page flipping for OpenGL.

Most of the time, you'll only get page flipping when your rendering window covers the entire screen. In windowed mode the driver most likely reverts to blits, but YMMV.

Anyway, there are AFAIK no direct means for OpenGL to detect either method being used.

Furrage
03-17-2002, 01:36 PM
You say if you render to the entire screen. Is that proven or just an assumption? I'm also assuming that page flipping must be faster than blitting to the whole screen. Am I right?

zeckensack
03-17-2002, 02:21 PM
Originally posted by Furrage:
You say if you render to the entire screen. Is that proven or just an assumption?
I think on the Rage3D forums, someone claimed a >10% performance boost in one of Humus' demos when going from 'almost' fullscreen to real fullscreen. Humus attributed that to the driver switching from blits to flips and I think that does make sense. No further proof.


I'm also assuming that page flipping must be faster than blitting to the whole screen. Am I right?[/B]
I think so http://www.opengl.org/discussion_boards/ubb/smile.gif
Flipping consumes zero memory bandwith, so it just has to be faster.

[This message has been edited by zeckensack (edited 03-17-2002).]