Does anyone know of a good way to accomplish a transparent window effect. In non opengl apps people usually use XCopyArea on the root along with XShm and a subwindow mode of IncludeInferiors. But this won’t work ‘out of the box’ for opengl. I’d also like to avoid the overhead of XCopyArea. It seems like there should be a way to do it without leaving the chip. glReadPixels is almost what I want, but that only works for the current context (ie the window I’ve created to draw into), I want to read pixels from the root and other windows. Any ideas?