Patent attributes
An objective is to provide an image generation system and program which can overcome the problem of flickering in screen due to the appearance and disappearance of distant objects. A depth cueing processing is executed such that the color of an object being more distant from the viewpoint is made closer to the target color. At the same time, the alpha value is varied such that an object being more distant from the viewpoint is made more transparent. By drawing the most distant background including a color different from the target color, the generated images can be improved in variety. The depth cueing and alpha value varying processings are carried out on condition that the object is positioned within the depth cueing area. The depth cueing value and alpha value for each vertex in the object are varied based on a Z-value for the vertex. Objects to be varied in the alpha value are sorted such that they are drawn sequentially from an object nearest to the viewpoint. This prevents the alpha blending to be executed at an overlap area of the adjacent objects.
