Complex Regions in Topological Queries

We describe a uniied framework for representing and manipulating binary topological relationships between complex regions, which are arbitrary compositions of homogeneous 2-dimensional surfaces, possibly with holes. Previously, compositions of regions and regions with holes were treated separately and in a restrictive scenario, where it is required that the composing regions should be disconnected. We point out that this restriction could lead to an anomaly in answering queries with topological constraints on composite regions in probably most GIS applications. In our framework, compositions of possibly connected regions with or without holes are allowed. Incorrect answers to topological queries involving complex regions are therefore avoided. Our work nicely extends the Egenhofer-Franzosa's model, originally developed for mod-eling binary topological relationships between simple regions.