IMAGE GENERATION SYSTEM, PROGRAM AND INFORMATION STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide an image generation system capable of effectively representing directional write expression with a small number of polygons, and to provide a program and an information storage medium. SOLUTION: The absolute valueθof an angle in an XZ plane between a straight line 300 connecting the position of the virtual camera C and the position of a light source LS, and an optical axis 310 of the light source LS is calculated in an object space defined by a Z axis and an XY plane crossing orthogonally with the Z axis in the case of defining the direction of a virtual camera C as a viewpoint as the Z axis. A deformation object (deformation primitive) obtained by deforming a given object in accordance with the angleθand a distance L from the light source LS is arranged on the optical axis 310. The length of the vertical axis of the deformation object Pi is defined on the basis of a distance Li. The length of the horizontal axis of the deformation primitive Pi is defined on the basis of such a value at which the object Pi comes into contact with the Z axis when the angle 0 made between the Z axis and the optical axis is at 90 deg. in the case the light source LS is arranged on the Z axis.