DBE is an extension to the X server that provides a
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Note: MBX (the
DBE XdbeQueryExtension XdbeGetVisualInfo XdbeFreeVisualInfo XdbeAllocateBackBufferName XdbeDeallocateBackBufferName XdbeSwapBuffers XdbeBeginIdiom XdbeEndIdiom XdbeGetBackBufferAttributes
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Performing Buffer Swaps On Vertical BlankFor performance reasons, the default DBE behavior is to not synchronize buffer swaps with the monitor's vertical retrace period. In some instances, therefore, image tearing (seeing part of the old image and part of the new image on the display at the same time) could be visible while swapping large DBE windows. For those instances where tearing would occur and is undesirable, an optional X server mode is available to allow for synchronization of buffer swaps with vertical retrace. To activate this optional X server mode, set the following screen option in the X*screens File before the X server is started:
SwapBuffersOnVBlank
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Note: MBX_SWAP_BUFFERS_ON_VBLANK is obsolete with this release. The SwapBuffersOnVBlank Screen Option works for both DBE and MBX.
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Determining Swap PerformanceThe DBE API does not allow users to determine if
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