MGV: a system for visualizing massive multidigraphs

摘要

Describes MGV (Massive Graph Visualizer), an integratednvisualization and exploration system for massive multidigraphnnavigation. It adheres to the visual information-seeking mantra:noverview first, zoom and filter, then details on demand. MGV's onlynassumption is that the vertex set of the underlying digraph correspondsnto the set of leaves of a pre-determined tree T. MGV builds annout-of-core graph hierarchy and provides mechanisms to plug in arbitrarynvisual representations for each graph hierarchy slice. Navigation fromnone level to another of the hierarchy corresponds to the implementationnof a drill-down interface. In order to provide the user with navigationncontrol and interactive response, MGV incorporates a number ofnvisualization techniques like interactive pixel-oriented 2D and 3D maps,nstatistical displays, color maps, multi-linked views and a zoomablenlabel-based interface. This makes the association of geographicninformation and graph data very natural. To automate the creation of thenvertex set hierarchy for MGV, we use the notion of graph sketches. Theyncan be thought of as visual indices that guide the navigation of anmultigraph too large to fit on the available display. MGV follows thenclient-server paradigm and it is implemented in C and Java-3D. Wenhighlight the main algorithmic and visualization techniques behind thentools and, along the way, point out several possible applicationnscenarios. Our techniques are being applied to multigraphs defined onnvertex sets with sizes ranging from 100 million to 250 million vertices