Optimization in KWin 4.6

“Apart from the scripting interface KWin will not ship any major
new feature in 4.6. Most of the work I did for 4.6 was to improve
the overall performance of our compositing engine. One of the first
improvements I added was for the text and icon overlays in our
effects. Now the texture and geometry is always cached and Texture
from Pixmap (TFP) is used instead of costly QPixmap/QImage
conversations.

“Another area which saw great improvements are effects which
transform one window. These effects used to cause the whole screen
to repaint even if only a small region changed. Most prominent
visible is this with the Show Paint effect enabled and for example
Sliding Popups or Wobbly Windows. Those effects are now repainting
only the changed area which is a great improvement, especially
considering that there is less blurring involved. The changes seem
to make a difference as developers running trunk asked in #kwin if
we changed something in Wobbly Windows.”

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