PURPOSE: To provide a method drawing the image of a mesh made of a Delaunay's tetrahedron.
CONSTITUTION: In this method, a root of a partial differentiation equation to facilitate the interaction with the user. The user selects interactively an object area in the inside of a mesh and the area is displayed in this method. This method utilizes a specific characteristic of Delaunay's tetrahedron. In the 1st step, a circumscribed sphere of each tetrahedron of the mesh is calculated. It is required to obtain a value of a 4×4 determinant for the calculation of a center of circumcircle and an outer diameter of each tetrahedron and the calculation is made only once. When a lane including a 2-dimension plane of a convex polyhedron is decided, the tetrahedron is sequenced from a visual point. A power function of a visual point as to each circumscribed sphere is calculated for a given visual point and the tetrahedrons are classified in the ascending order of respective power functions. The efficiency is improved by calculating power functions independently of each visual point in advance. The tetrahedron is drawn from the rear side toward the front side.
DEREKU RIIBAA
RII RICHIYAADO NATSUKUMAN
BADATSUKEDASU TOOMASU RAJIYAN
