Patent ID: 7057625

Claim:
A computer-readable medium storing a program for drawing and displaying an image of given objects in a three-dimensional virtual space, the program causing a computer to perform the steps of: (a) calculating distance from an eye point to an object based on coordinates thereof in the three-dimensional virtual space; (b) comparing the distance with a predetermined semi-transparent distance, as well as with a predetermined invisible distance which is longer than the semi-transparent distance; (c) selecting the object as a visible object that is to be subjected to image drawing operations when the distance of the object is shorter than the invisible distance; (d) drawing an image of the visible object, in opaque mode when the distance is shorter than the semi-transparent distance, and in semi-transparent mode with transparency given by a monotonically increasing function of the distance when the distance is longer than the semi-transparent distance; and (e) displaying the image of the visible object drawn at the drawing step, the object being displayed as an opaque object when the object is drawn in the opaque mode and the object being displayed as a semi-transparent object when the object is drawn in the semi-transparent mode.