Hi Johannes,
You are righth, it is blazing fast for moving around and zooming in/out on moderate zoom levels. However, my old hardware (ATI Radeon Mobility X1400), or the Linux drivers for it, may not be good enough to zoom out to see the whole matrix.
This is a great piece of code but also so advanced (to me at least) that I need to do some studying to be able to continue from this. I hope that this leads to a real application one day: I've dreamed of a project where I could learn some nice Qt programming but I also feel that the project has to be related to my research work to be justified. This is exactly that!
Lari
P.S. Sorry about the bug! Wasn't first time that I got rand() limits wrong...
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