Version: (using KDE Devel) Installed from: Compiled sources Compiler: gcc 4.2.2 OS: Linux Put a plasma applet on the workspace, the "Zoom Out" the workspace and start moving the applet: you can see that if you move the applet where is the desktop wallpaper the movements are slow, when you drag it on the "white zone" the movement are very fast.
Created attachment 22350 [details] Image of the zones
i can confirm this. Plasma would be great! if it would move on a wallpaper in the same speed as it does on the white background
this is due to the scaling that happens when zoomed out. the background repaints and is then rescaled. i'm guessing that in Qt 4.3 is rescales the entire item in memory rather than just the effective exposed rect; i'll have to test 4.4 to see if this is the same, but i won't be fixing this before 4.1 i don't think. this is just a performance quibble, while there are too many significant issues to address in the meantime.
so even in qt 4.3 it's only painting the absolute necessary, but all the math to scale in real time is killing us. will have to look and see what we can do in the Qt layers below us and see how things improve from there..
Qt 4.4 and KDE 4.1 significantly improves performance in this area