Basic Interface for Geometric Modeling Systems.

Geometric modeling systems must have a variety of capabilities to describe products' shapes, because machine functionalities are realized by its geometric features.However, conventional geometric modeling systems are not powerful and flexible enough for handling those features of products in design and manufacturing processes.In order to cope with this problem, basic interface for geometric modeling systems using generalized topology and geometry is proposed in this paper.The interface provides functionalities for handling several types of topology models, such as solids, surfaces, and wireframe edges.A non-manifold data structure based on neighborhood relationships is used for integrating those topology models.The non-manifold representation is sufficient and efficient for describing adjacency ordering and is also suitable for operations managing connectivities.Since geometric information is generalized by abstracting geometric data type , the interface is so flexible to adapt itself to specific geometric data.Furthermore, the interface enables us to handle simultaneously various types of geometric data by using multiple descriptions.