On Edge Bundling and Node Layout for Mutually Connected Directed Graphs

Directed graphs are used to represent variety of information, including friendship on social networking services (SNS), pathways of genes, and citations of research papers. Graph drawing is useful to intuitively represent such datasets. This paper presents an edge bundling and a node layout technique for tightly and mutually connected directed graphs. Our edge bundling technique includes three features: ordinary bundling of edges connecting common pairs of node clusters, convergence of multiple bundles connecting to the same node cluster, and shape adjustment of two bundles connecting the same pair of node clusters. This paper includes a case study with a directed paper citation graph.