Semantically Correct 2.5D GIS Data — the Integration of a DTM and Topographic Vector Data

This paper presents an approach for a semantically correct integration of a 2.5D digital terrain model (DTM) and a 2D topographic GIS data set. The algorithm is based on a constrained Delaunay triangulation. The polygons of the topographic objects are first integrated without considering the semantics of the object. Then, those objects which contain implicit height information are dealt with. Object representations are formulated, the object semantics are considered within an optimization process using equality and inequality constraints. First results are presented using simulated and real data.