| The focus of this study is the geometric set operations of union, intersection, and difference as used in computer-aided shape modeling for building design.;The notion of integrated computer-aided building design recognizes the fact that the design of a building is the resolution of many disparate and often conflicting design objectives. The primary objective of CABD is to bring together as much design information as possible, in an integrated database that holds both spatial and non-spatial data.;Shape data is a significant component of the integrated database. It is the mathematical description of the physical components of the building, such as: foundations, structure, interior partitions, cladding, mechanical services, electrical equipment, and furnishings, as well as the spaces between the solid objects.;A set of shape operations on a class of shapes has been defined and implemented that extends the familiar set operations on polygons and polyhedra to a matrix of operations on mixed shape-type pairs. The shapes are planar and include vertex, edge, face, and polyhedron-sets.;There are two assumptions from which this work arises. The first is that integrated building design is more effective than piecemeal design. The second is that in order to do integrated computer-aided building design (CABD), there must be a complete mathematical description of the physical objects and spaces that make up the design.;These operations will greatly enhance the utility and scope of computer-aided shape modeling for the design professional. They can be used to model the spatial development of the design from building program through sketch, preliminary, and final design. |
