Shape evaluation method, shape evaluation device, and device having the shape evaluation device

A shape evaluation device for evaluating a curved surface of a shape by a characteristic line, wherein

• said characteristic line is a circular highlight line or a circular reflection line which an annular light source in an arbitrary direction in a three-dimensional space forms on the curved surface, said annular light source having a radius and a center that are variable,
• computing means for forming the characteristic line by extracting a point, where the light from said annular light source irradiates or reflects on the curved surface, from the points on the curved surface, and said computing means is obtaining a vectorial correspondence between each of the points on said curved surface and points on said annular light source.

A program medium recording a program causing a computer to execute computing to form a characteristic line on a shape surface, wherein

• said characteristic line is a circular highlight line or a circular reflection line which an annular light source in an arbitrary direction in a three-dimensional space forms on said curved surface, said annular light source having a radius and a center that are variable,
• said computing is extracting a point, at which the light from said annular light source irradiates or reflects on said curved surface, from points on said curved surface, and
• said computing is obtaining a vectorial correspondence between each of the points on said curved surface and points on said annular light source.