| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a game system for adding the strength and weakness of a contour to an object having a possibility of being seen at various angles, and an information storage medium. SOLUTION: The thickness of a contour image is changed in accordance with the shape of a surface of an object OB near a contour. If an angleθmade between a first vector heading toward a viewpoint from a point on the surface and a normal vector changes from a right angle at a low rate of decrease, a thick contour image is drawn, and if the angleθchanges a high rate of decrease, a thin contour image is drawn. A contour image is drawn in the vicinity of an area where the angleθfalls within the range ofα<=θ<=90 deg.. A texture for a contour designated with texture coordinates calculated on the basis of an inner product by the first vector and the normal vector is mapped onto the object. Another contour image with fixed thickness is further drawn. If a polygon is frontward, a contour image is drawn between adjacent vertexes where a backward normal vector is set, and if the polygon is backward, a contour image is drawn between adjacent vertexes where a frontward normal vector is set.</p> |
