Non-manifold modelling: an approach based on spatial subdivision

This paper deals with the problem of creating and maintaining a spatial subdivision, deened by a set of surface patches. The main goal is to create a set of functions which provides a layer of abstraction capable of hiding the geometric and topological problems which occur when one creates and manipulates spatial subdivisions. The study of arbitrary spatial subdivisions extends and uniies the techniques used in nonmanifold solid modeling and allows the modeling of heterogeneous objects.