A review of solid shape modelling based on integrity verification

The potential benefits of using a canonical model for representing the shapes of solid objects has led to the design and implementation of a number of geometric modellers, with varying capabilities. This paper reviews the approaches taken in solid modelling by defining the well-formedness conditions which must be implemented in any modelling system. The methods for satisfying the well-formedness constraints in the various solid modelling methods are reviewed, using the concept of integrity constraint. The incorporation of integrity constraints, both explicitly and implicitly, into solid modellers are considered, with particular focus on boundary modellers. The use of integrity constraints for defining shape families and assembly families are also presented. The result is a unified view of solid shape modelling systems that enables their classification and extension into particular application areas.