Exploiting 2D Concepts to Achieve Consistency in 3D GIS Applications

摘要

This article provides a formal data model to cover many 3D applications in GIS. It is based on a 2D model and preserves the algorithmic and conceptual simplicity of the 2D case as much as possible. Integrity axioms guarantee the consistency of the model in a mathematically provable way. These axioms are effectively and efficiently checkable by automatic procedures. The model extends Digital Terrain Models by allowing for vertical walls and projections like balconies or ledges. The conceptual simplicity is due to the two-dimensional topology of the model. Thus bridges and tunnels cannot be represented; we show how to detect and handle these cases efficiently. Based on this model, spatial objects and their aggregation structures can be defined consistently.