#18 Problem with ForceDirectedLayout

[Jens Kanschik]

In the topic map examples on the website, the ForceDirectedLayout seems to compute a position outside of the allowed range from time to time. Usually, one or more nodes have a location in the upper left corner and they don't move when the graph is moved.

Probably there is some rounding problem in the algorithm. The problem doesn't occur when using the TreeLayout as in the other examples.