For general graphs, the problem of a determining a planar layout of a graph with least edges crossing (the Crossing Number) is NP-hard. So some heuristic methods are used (like the Force based layout algorithms). The page below briefly describes the graphviz algorithms and suggests some ways to use them for benefit. It also has … Read more
Graphviz itself provides a solution for rendering large graphs. Namely, Graphviz includes sfdp, a multiscale version of fdp (also in graphviz, similar to neato) for the layout of large undirected graphs which has been useful for drawing large graphs (70k nodes, 500k edges) in my project. You can find documentation for this software on the … Read more
I’ve just put together what you may be looking for: http://www.graphdracula.net It’s JavaScript with directed graph layouting, SVG and you can even drag the nodes around. Still needs some tweaking, but is totally usable. You create nodes and edges easily with JavaScript code like this: var g = new Graph(); g.addEdge(“strawberry”, “cherry”); g.addEdge(“cherry”, “apple”); g.addEdge(“id34”, … Read more