Abstract: A method includes: an input step of inputting boundary surface information 11 on an object to a computer using the computer; a grid sampling step of determining cutting points 13 where the boundary surface cuts across edges of a predetermined rectangular parallelepiped grid 12 and normal vectors 14 of the boundary surface at the cutting points, and storing them in a storage unit as primary data 15; a D-polyhedron data generation step of connecting adjacent cutting points with a line segment to form a triangle one by one for generating D-polyhedron data 16 constituted of triangles only; and a V-polyhedron data generation step of generating V-polyhedron data 17 constituted of intersections of a plurality of infinite planes passing through the cutting points and whose normals coincide with the normal vectors. Any one of the D-polyhedron data and the V-polyhedron data is generated from the primary data 15, and the other is generated as a dual.

Abstract: A method includes: an input step of inputting boundary surface information 11 on an object to a computer using the computer; a grid sampling step of determining cutting points 13 where the boundary surface cuts across edges of a predetermined rectangular parallelepiped grid 12 and normal vectors 14 of the boundary surface at the cutting points, and storing them in a storage unit as primary data 15; a D-polyhedron data generation step of connecting adjacent cutting points with a line segment to form a triangle one by one for generating D-polyhedron data 16 constituted of triangles only; and a V-polyhedron data generation step of generating V-polyhedron data 17 constituted of intersections of a plurality of infinite planes passing through the cutting points and whose normals coincide with the normal vectors. Any one of the D-polyhedron data and the V-polyhedron data is generated from the primary data 15, and the other is generated as a dual.