Converting Hybrid Wire-frames to B-rep Models

Jie-Hui Gong (1, 2) , Hui Zhang (2) , Yi-Wen Zhang (1) , Jia-Guang Sun (2, 3)

1 THSS - School of Software
2 CAD - Computer Aided Design
3 PRECISE - Purdue Research and Education Center for Information Systems in Engineering

Solid reconstruction from engineering drawings is one of the efficient technologies to product solid models. The B-rep oriented approach provides a practical way for reconstructing a wide range of objects. However, its major limitation is the computational complexity involved in the search for all valid faces from the intermediate wire-frame, especially for objects with complicated face topologies. In previous work, we presented a hint-based algorithm to recognize quadric surfaces from orthographic views and generate a hybrid wire-frame as the intermediate model of our B-rep oriented method. As a key stage in the process of solid reconstructing, we propose an algorithm to convert the hybrid wire-frame to the final B-rep model by extracting all the rest faces of planes based on graph theory. The entities lying on the same planar surface are first collected in a plane graph. After all the cycles are traced in a simplified edge-adjacency matrix of the graph, the face loops of the plane are formed by testing loop containment and assigning loop directions. Finally, the B-rep model is constructed by sewing all the plane faces based on the M¨obius rule. The method can efficiently construct 2- manifold objects with a variety of face topologies, which is illustrated by results of implementation

Mots clés: 2-manifold; Möbius rule; graph theory; model conversion; solid reconstruction

Domaines: Ingénierie assistée par ordinateur

Jie-Hui Gong, Hui Zhang, Yi-Wen Zhang, Jia-Guang Sun. Converting Hybrid Wire-frames to B-rep Models. SPM '07: Proceedings of the 2007 ACM symposium on Solid and physical modeling, ACM, Jun 2007, Beijing, China. pp.283-289, ⟨10.1145/1236246.1236286⟩. ⟨inria-00202636⟩