The paper describes the definition and implementation of topological operators which form part of a 3D Spatial Query Language that has been developed to query Building Information Models using spatial conditions. The partial models resulting from spatial queries can be used as input for numerical simulations and as exclusively modifiable subsets in the context of collaborative planning activities, for example. Because human language is vague and ambiguous, the semantics of the provided 3D topological predicates are formally defined using an adapted version of the 9-intersection model originally developed by the GIS research community for 2D space. The paper further describes a novel approach for implementing 3D topological operators based on an octree representation of the geometric objects whose topological constellation is the subject of investigation.     «

The paper describes the definition and implementation of topological operators which form part of a 3D Spatial Query Language that has been developed to query Building Information Models using spatial conditions. The partial models resulting from spatial queries can be used as input for numerical simulations and as exclusively modifiable subsets in the context of collaborative planning activities, for example. Because human language is vague and ambiguous, the semantics of the provided 3D topolo...     »