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OpenGL OpenGL: How to detach frame rate form refresh rate

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this is os specific
in windows u can disable it in the display properties tab, also theres an extension win_swap_interval (see my site for a demo)

http://members.xoom.com/myBollux

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It''s all about windows... Which example do you speak about?

please helpme a bit more

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bottom of page click on "opengl extensions" then click "win swap interval"

http://members.xoom.com/myBollux

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If you are referring to the fact that when you use fullscreen exclusive mode that the speed of you rendering matches the speed of your refresh rate. The reason is simple. It is because of the surface option to wait for the verticle refresh before flipping the back buffer to the primary buffer. If you were to ignore this, your program would traverse though your code at full speed without stopping, but you would get a nasty flashing glitches in your graphics (fine for testing). To wait for your verticle refresh is to bring your main graphics rendering loop to a screeching halt until your refesh has flipped the surface. It is okay however, since when the flipping is done, your code blasts through the loop until it gets back to the flip surface routine again. The only way to have code run constantly without stopping for the flip is to run a separate thread.

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Actually I''ve noticed a number of things when running Win2k vs. WinMe.

In Win2k, when i run my demo in full screen mode, the FPS value cannot pass the refresh rate. However, running it in windowed mode, it does.

This problem does not occur under WinMe.
Also, i noticed the FPS is lower in fullscreen compared to windowed when running under Win2K. Again this problem does not occur in WinMe.

-Xtreme.

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Sorry but I have had this problem for a long time and i think it is related to the same issue. I notice in my games, there are set frame rates i can get. eg normally i get a frame rate of ~72, but there is a certain point beyond which adding 1 more poly causes frame rate to drops to 35, then again 24 and... I heard that this has to do with refresh rate or something. Could anyone explain to me why and what this is? is there a way to force a more gradual drop in framerate? Oh and i have noticed that this kindda doesn''t happen in Quake 3.

Thanks

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With VSync on you will only get factors of the refresh rate. With a 60Hz refresh rate, you will only get 60FPS, 30FPS, 15FPS and so on. You can''t get a more gradual drop unless you turn VSync off which is undesirable.

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quote:
Original post by Xtreme
In Win2k, when i run my demo in full screen mode, the FPS value cannot pass the refresh rate. However, running it in windowed mode, it does.



Strange, I can run games in full screen with vsync disabled and get a higher fps than my refresh rate. Running Win2k pro w/ a 32meg geforce sdr, leaked 10.80 drivers.

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As was said in the previous post, I get higher numbers than my refresh rate in fullscreen in Win2K as well. Oh, and while I''m on this topic, I read a review about WinME vs. Win2K''s game performance, and Win2K was faster for almost every game except UT .

"Finger to spiritual emptiness underlying everything." -- How a C manual referred to a "pointer to void." --Things People Said
Resist Windows XP''s Invasive Production Activation Technology!
http://www.gdarchive.net/druidgames/

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