Node-based data visualization library in c or objective c

I'm looking for a library in c or objective c that does node-data visualizations similar to http://arborjs.org/

helpful answers include,

1. what are graphs like that called?
2. names of libraries that do something like that.
3. suggestions for implementation.

I'm targeting iOS and/or MacOS, hence c or objective-c/cocoa. On iOS the javascript version runs super slow.

Thanks!

Edit: GraphViz looks great. I'm a little concerned it may have d开发者_StackOverflowependencies that are GPL, and thus can't be used on iOS... looking into that now.

Actually there seems to be an Objective-C port of arborjs, see https://github.com/epreston/PSArborTouch.

This is called graph visualization and the best toolkit that I know for it is called GraphViz. It has C libraries.

That sort of graph doesn't have a particular name; not without knowing more context. So without more information, it's a "graph".

As for a library, there's an open source project called GraphViz. You'll have to dig a bit to find the drawing code, but it's in there somewhere. :)