A computer-readable storage medium has stored thereon an program that is executed in a display apparatus that takes an image of a virtual three-dimensional space in which a first object and a second object are present, by a virtual camera and renders the virtual three-dimensional space. The program allows the apparatus to generate a silhouette image for representing a silhouette of the first object, in which silhouette image, gradation information changes in accordance with a distance from the second object to each part of the first object; to generate an image of the second object that is seen from the virtual camera; and to synthesize the silhouette image on the image of the second object that is seen from the virtual camera, such that the silhouette image is darker at a portion thereof corresponding to a part of the first object closer to the second object.