GUI Performance Improvement

[<klaus.pichler AT stud.unileoben.ac.at>]

Hey :)

I have a slightly Problem with my GUI Performance on bigger Graphs.
I am using Graph Stream to show "Open Street map" Streets and to apply
certain algorithms on that. My problem is, that it took really long for 
the graph panel to refresh, when I change the zoom level or change 
the centerpoint on big Graphs. Refreshtime for the panel is about 4s 
for a Graph with 664468 Nodes and 673133 Edges. (Dont use ui.quality or
ui.antialias) For small Graphs it works all fine :)  
I would like to know, if there is any chance to improve the performance, or
if I reached the limits. I am using a Mac by the way.

Thx from austria
Klaus