There is increasing evidence that 3D visualization of complex structures has advantages over 2D visualization. While nested directed graphs are an important method of representing information in 2D or 3D, they must be effectively organized in order to be understood. Most work on graph layout has assumed that fully automatic layout is desirable. Through our work with graphs representing large software structures, we have found that, due to the importance of the semantic content, it is necessary to combine automatic layout with manual layout. This paper describes a system called GraphVisualizer3D, which was designed to help people understand large nested graph structures by displaying them in 3D. This system is currently being applied to the problem of understanding large bodies of software. In this paper we present the layout strategy developed for GraphVisualizer3D, which combines manual layout techniques and automatic algorithms in a synergistic manner. In order to facilitate manual layout, a grid system is provided that can be nested to any arbitrary depth. The automatic layout is accomplished by layering followed by a node migration algorithm, whereby nodes migrate to their final position under the influence of a variety of different forces. Options are provided to allow users to switch back and forth between manual layout and automatic layout. GV3D has been tested with large examples containing more than 35,000 nodes and 40,000 relationships.


Center for Coastal and Ocean Mapping

Publication Date


Journal or Conference Title

Interanational Conference on Visual Information Systems (VISUAL)

Conference Date

Dec 15 - Dec 17, 1997

Publisher Place

San Diego, CA, USA

Document Type

Conference Proceeding