* Disable snow effect if there is an active full screen effect as it causes some problems. E.g. in desktop grid the snow flakes are painted several times and by that look terrible.
CCBUG: 176489
svn path=/trunk/KDE/kdebase/workspace/; revision=890836
* move position updates of flakes to shader
* remove the for-loop which updates the flakes. This is handled in the loop for painting the flakes
* Don't test in each frame if a flake is on the screen. Precalculate the number of frames when then flake is on the screen and count the flakes.
* Set PAINT_SCREEN_TRANSFORMED
* Remove all unneeded code (like a QTime object when we already get the time in the method)
Now it takes ~ 17 % of CPU usage on my system. Seems to be the maximum of what is possible.
svn path=/trunk/KDE/kdebase/workspace/; revision=884305
