Using Hierarchical Edge Bundles to visualize complex ontologies in GLOW

In the past decade, much effort has been put into the visual representation of ontologies. However, present visualization strategies are not equipped to handle complex ontologies with many relations, leading to visual clutter and inefficient use of space. In this paper, we propose GLOW, a method for ontology visualization based on Hierarchical Edge Bundles. Hierarchical Edge Bundles is a new visually attractive technique for displaying relations in hierarchical data, such as concept structures formed by 'subclass-of' and 'type-of' relations. We have developed a visualization library based on OWL API, as well as a plug-in for Protégé, a well-known ontology editor. The displayed adjacency relations can be selected from an ontology using a set of common configurations, allowing for intuitive discovery of information. Our evaluation demonstrates that the GLOW visualization provides better visual clarity, and displays relations and complex ontologies better than the existing Protégé visualization plug-in Jambalaya.