Visually exploring multi-dimensional code couplings

Dependencies and coupling relationships between code entities can be manifold. They form a graph structure with several different types of edges. Visualizing these graphs presents two challenges: the often large size of the graphs and the readable representation of the different edge types. In this paper we present a new node-link graph visualization technique addressing these challenges. Different types of edges are represented in multiple, small diagrams. These diagrams are placed side-by-side like the pictures of a comic strip. Among other things, edge bundling is applied to improve the scalability of the visualization. Elaborate interaction techniques with respect to focusing and merging data aim at providing help for comparing different edge types. A case study demonstrates how the visualization can be used to analyze a mid-size software project in practice.