A general framework for visualizing abstract objects and relations

Pictorial representations significantly enhance our ability to understand complicated relations and structures, which means that information systems strongly require user interfaces that support the visualization of many kinds of information with a wide variety of graphical forms. At present, however, these difficult visualization problems have not been solved. We present a visualization framework for translating abstract objects and relations, typically represented in textual forms, into pictorial representations, and describe a general visualization interface based on this framework. In our framework, abstract objects and relations are mapped to graphical objects and relations by user-defined mapping rules. The kernel of our visualization process is to determine a layout of graphical objects under geometric constraints. A constraint-based object layout system named COOL has been developed to handle this layout problem. COOL introduces the concept of rigidity of constraints in order to reasonably handle, a set of conflicting constraints by use of the least squares method. As applications of our system, we show the generation of kinship diagrams, list diagrams, Nassi-Shneiderman diagrams, and entity-relationship diagrams.