Zack Rusin, the well-known X.Org and KDE hacker, has written a new blog post concerning the Qt tool-kit and the different options that are available when it comes to rendering graphics. Qt currently can target a pure CPU raster engine, using X11 with the X Render extension for providing some GPU-assisted acceleration, or using an OpenGL engine. The renderer that is used by Qt depends upon the platform, what portions of the Qt API are being used by a given program, and whether the graphics system was overrode when starting the program.
In Zack's blog post, entitled 2D in KDE
, he describes at length these three graphics rendering engines for Qt. Obviously, using the CPU raster engine is the most taxing while using X Render is better, but using OpenGL is the best, generally. Zack concludes his lengthy blog post with "the quicker we get the rendering stack to work on top of OpenGL the better off we'll be."