Computer readable program product, method of image processing and image processing system

摘要

A method of image processing where a location of a three-dimensional object to be displayed by a quadrilateral polygon is displayed as a natural concave/convex shape and thereby the mode of change of the form of the three-dimensional object is displayed without a strange feeling, includes drawing and recording a quadrilateral polygon designated for division. The method also includes provisionally dividing that quadrilateral polygon into two triangular planes by a separating line connecting two facing vertexes, and judging if the two triangular planes form a convex shape facing the outside of the three-dimensional object. The method also includes dividing the quadrilateral polygon by that provisional division pattern if forming a convex shape, and dividing the quadrilateral polygon by another division pattern using a separating line connecting the remaining two vertexes if forming a concave shape so that the two triangular planes form a convex shape facing the outside of the three-dimensional object. Thus, the location of the three-dimensional object displayed by the quadrilateral polygon is displayed to form a convex shape facing the outside.