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RJH
06-30-2001, 07:15 AM
Is there any way to tell OpenGL to refresh the screen after drawing each Raster line instead of waiting for the entire screen to be rendered? Is there a performance penalty for doing his? Thanks for any help.

DFrey
06-30-2001, 07:33 AM
I think what you are asking about is if it is possible to disable the vertical sync. And well, the answer is, maybe. In Windows, there is an extension that may be available, WGL_EXT_swap_control, using that you can request that sync be disabled by using a value of 0. However, most video drivers give users an option to over-ride this function. A user may be able to force it always off, always on, or default to on. The end result is, you can use the extension, but you can't be certain it'll always have the desired effect.

RJH
07-05-2001, 04:08 AM
Originally posted by DFrey:
I think what you are asking about is if it is possible to disable the vertical sync. In Windows, there is an extension that may be available, WGL_EXT_swap_control, using that you can request that sync be disabled by using a value of 0.

thanks for the reply but I can't find anything on "WGL_EXT_swap_control", nearest match is "wglSwapLayerBuffers".

harsman
07-05-2001, 04:26 AM
It's an extension. See:
http://oss.sgi.com/projects/ogl-sample/registry/EXT/wgl_swap_control.txt