Lossless representation of topological spatial data

We present a data structure used to represent planar spatial databases in the topological data model. Conceptually, such databases consist of points, lines between these points, and areas formed by these lines. The data structure has the distinctive feature that it is geared toward supporting queries involving topological properties of the database only: two databases that are topologically equivalent have the same representation. Moreover, no information is lost in this way: two databases that are not topologically equivalent never have the same representation