Performance Optimizations For KDE's KWin 4.6

While some developers and other KDE contributors are busy voicing their opinions over merging the KDE libraries into the upstream Qt, which would lead to either KDE 5.0 or KDE 6.0 depending upon how it's implemented and if it's actually carried out, KDE Software Compilation 4.6 is still on the way and should officially arrive by the end of January. Martin Graesslin, who works on much of the KWin compositing manager and previously said KDE SC 4.7 may support OpenGL 3.x for compositing, has written about some of the KWin changes for KDE 4.6.

KWin in KDE SC 4.6 is not going to change anything radical, but there are some scripting interface changes and some performance improvements within the compositing engine. With KWin 4.6, texture and geometry data is now always cache and the GLX_EXT_texture_from_pixmap extension is utilized rather than QPixmap/Qimage.

According to Martin, there are great improvements for effects that transform a single window, since these KWin effects no longer cause the entire window to be repainted. There's also an optimization for the Lanczos filter and other improvements.

Martin talks about KWin 4.6 in this blog post.