Paints usually originate somewhere up the parent chain making all icons repaint at the same time.
Prior to this commit, each icon called render on the parent meaning that, for example, the panel was being painted to an offscreen pixmap as many times as there are icons.
This commit consolidates those offscreen paints into one, meaning that with 10 icons there is a 10x speedup. :)

After this, I'll move the paint compression/timer stuff over as well to cut down on the timers.