多面体の階層構造による記述とその生成手続きに関する研究(第2報)

穴のある立体の場合

抄録

Various problems of constructing and processing polyhedra represented by the hierarchical tree structure of convex components have been approached by the authors for several years. To decompose a polyhedron into the smaller components may be necessary in the processes of constructing the structure. A method for this type of problem, which is based on the idea of utilizing the boundary edge line loops between used and unused faces for making the convex hull of the original one, is presented for the case of a polyhedron with holes. The main feature of this method is as follows. (1) The polyhedron can always be decomposed uniquely. (2) No vertex is newly produced. (3) The number of newly created components may not become so large.