void PEXCopyPixmapToAlphaBuffer( Display *display, PEXRenderer renderer, Pixmap pixmap )
None.
Invoke PEXCopyPixmapToAlphaBuffer to copy the content of the specified pixmap into the alpha buffer.
If the renderer state attribute of the renderer specified by the renderer argument is PEXRendering or PEXMultipassRendering, then the renderer copies the content of the specified pixmap to the alpha buffer bound to the drawable associated with the renderer. The format of the values copied from the pixmap is implementation-dependent.
To determine the correct alpha buffer depth for copying the pixmap, see the PEXGetAncillaryBufferInfo function.
The renderer's clip list is not considered by this function.
If the renderer state is PEXPicking, then the values copied to the alpha buffer have an implementation-dependent effect.
If the renderer state is PEXIdle, then this function has no effect.
For a list of all Renderer functions and related topics, see Rendering.