Intelligent icon positioning for interactive map-based information systems

The combination of map displays with icon techniques is well-suited for visualizing geo-spatial dependent multivariate data. The requirements for icon placement on the map, although not trivial, are not properly attended by most interactive visualization systems. In cartography, a number of methods for automatic text label placement and map generalization has been developed. These are focused on high-quality results, leading to long response times not suited for interactive environments. In this paper an interactive, scalable approach borrowing from cartographic methods is presented which is based on an iterative displacement of icons combined with a focus & context technique.