X Rendering Extension

X Window extension X Rendering Extensionxclock uses the render extension for rendering translucent and antialiased clock handsOriginal authorX.Org FoundationPlatformUnix, Unix-like The X Rendering Extension (Render or XRender) is an extension to the X11 core protocol to implement image compositing in the X server, to allow an efficient display of transparent images. History It was written by Keith Packard in 2000 and was first released with XFree86 version 4.0.1. Its design was influenced by rio, the windowing system for Plan 9. Motivation The core X Window System drawing protocol does not have a way to efficiently draw transparent objects: A computer display is composed of individual pixels, which can only show a single color at a time. Thus transparency can only be achieved by mixing the colors of the transparent object to be drawn with the background color (alpha compositing). However, the standard X protocol only allows drawing with solid color, so the only way to achieve transparency is to fetch the background color from the screen, mix it with the object color, then write it back, which is fairly inefficient. Since many operations require transparency (for example spatial ant