What options are available for the layout of directed or undirected graphs in .NET?

Question

By graph here I mean something resembling these images:

Answer 1

Northwoods offers a pure .NET solution in their GoLayout product. They offer tree, force directed, and layered digraph (which is not quite a Sujiyama effect, but not too far off for many if not most data sets). At $1790/seat it's expensive. There are also some limitations: most importantly, their implementations are designed for "human readable" graphs. I've given it data sets of over 5,000 nodes and had no issue, but I can also generate data sets of less than 500 nodes that cause it to have a stack overflow (recursing too deep). Depending upon your domain, it may (or may not) be a good fit. If you need a general layout package that handles any data set, I'd suggest GraphViz over Northwoods.

I have yet to use any of their WPF capabilities, but I know they have them. I've been using their stuff in WinForms land for a while.