Glitz is an OpenGL image compositing library. Glitz provides
Porter/Duff compositing of images and implicit mask generation for
geometric primitives including trapezoids, triangles, and rectangles.

The semantics of glitz are designed to precisely match the
specification of the X Render extension. Glitz does not only implement
X Render features like component alpha and image transformations, but
also support for additional features like convolution filters and color
gradients, which are not currently part of the X Render specification.

The performance and capabilities of glitz are much dependent on
graphics hardware. Glitz does not in any way handle software
fall-backs when graphics hardware is insufficient. However, glitz
will report if any requested operation cannot be carried out by
graphics hardware, hence making a higher level software layer
responsible for appropriate actions.