Topology of the Prism Model for 3D Indoor Spatial Objects

Topological relationships between spatial objects are an essential property of spatial objects. They are used for spatial analysis and query processing. In this paper, we first introduce an alternative 3D geometric model, called the prism model. The prism model is based on an extrusion method from 2D footprints of 3D objects. Then we study the correspondence between the 2D topology of footprints and the topologies of 3D objects using the prism model. We propose a method of topological analysis to implement topological operators for the prism model based on this study. This method is simpler and more efficient than the methods of the 3D spatial model. The topological operators are easy to implement since we can extend the 2D simple feature geometry of OGC provided by most spatial DMBS.