3D Map and object displaying apparatus and method, and navigation apparatus employing the method

An apparatus and method for displaying navigation guidance signboards as superimposed images on a 3D map is provided. "Translucent" is set as a transparency attribute (34) for a signboard, whereas "opaque" is set as a transparency attribute (34) for a diagram and/or a text string shown on the signboard. As a result, a navigation guidance signboard is displayed as a superimposed image on a three-dimensional map in such a manner that the diagram and/or text string appears opaque and that the signboard appears translucent. Thus, a user can visually recognize the diagram and/or text string indicating navigation guidance without fail, and yet see through the signboard (except for the portion in which the diagram and/or text string are shown) to the three-dimensional map.