Improving Layered Graph Layouts with Edge Bundling

We show how to improve the Sugiyama scheme by using edge bundling. Our method modifies the layout produced by the Sugiyama scheme by bundling some of the edges together. The bundles are created by a new algorithm based on minimizing the total ink needed to draw the graph edges. We give several implementations that vary in quality of the resulting layout and execution time. To diminish the number of edge crossings inside of the bundles we apply a metroline crossing minimization technique. The method preserves the Sugiyama style of the layout and creates a more readable view of the graph.