Preserving Coincidence and Incidence Topologies in Saalfeld's Polyline Simplification Algorithm

In this paper, we firstly describe two topological configurations that are not considered by Saalfeld’s polyline simplification algorithm: the coincidence topology, concerning the overlapping of two polylines or the overlapping of a feature point and a polyline, and the incidence topology, concerning the incidence of two polylines without having the incidence point represented as a common vertex. Afterwards, we suggest a simple modification in Saalfeld’s algorithm for preserving these topologies. Finally, we give some results of our simplification procedure and compare them to the ones of Saalfeld’s algorithm.