Multiscale mapping for the NSDI: Data modeling and representation

The National Spatial Data Infrastructure system integrates spatial data from many sources into products for describing, mapping, and planning for the Nation. Two major challenges of this system are combining different kinds of spatial data from disparate agencies and providing these data at multiple scales or even ranges of scales. The transformation of a road network taken from one data source into the representation of a built-up area for a different user illustrates an approach to these challenges.