Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The X Rendering Extension (Render or XRender) is an X Window System extension to implement Porter-Duff image compositing in the X server. It was written by Keith Packard in 2000 and was first released with XFree86 version 4.0.1. It provides several rendering operations and also does alpha blending. At present it is primarily used to implement antialiased fonts, but is expected to be used to implement drop shadows and translucency. Geometric figures are rendered by client-side tessellation into either triangles or trapezoids. Text is drawn by loading the glyphs into the server and rendering as a group. It is designed to target the 3D graphics capabilities of newer video cards.