Three-dimensional modeling by combining artificial with real data.

Issues arising in the graphics simulation of bone grafting and in the use of commercial libraries to create custom-designed models revolve on the ability to combine data defined in Volume Representation--as that generated by Computed Tomography scans--and user-defined data introduced in Boundary Representation--as vertices of polygons, for instance. To address these issues the authors propose a hybrid filling technique, which also processes conflicting adjacency information created by subsampling or digitization errors. A graphics experiment has been designed to illustrate the problems arising in the presence of objects defined partially in Volume and partially in Boundary Representation, and a method to handle them.