Algebraic Specification of a 3D-Modeler Based on Hypermaps

Abstract

We present the algebraic specification of a prototype interactive geometric modeler for 3D objects, whose topologies are represented by 3-dimensional generalized maps. After a reminder of some topological models, particularly maps and extensions, we begin with the more general frame of n-dimensional hypermaps. We specify algebraically a hierarchy of operations on hypermaps and generalized maps, which are embedded in a 3-dimensional Euclidean space. We make precise the modeling area and give the main functionalities of the modeler. We detail high-level operations on 3D objects, and some technical features of this software. Some constructions are explained using pictures. We show that hypermaps and algebraic specification constitute an efficient formal frame for developing large pieces of software in the area of boundary representation.