A parallax representation unit in a displayed image processing unit uses a height map containing information on a height of an object for each pixel to represent different views caused by the height of the object. A color representation unit uses, for example, texture coordinate values derived by the parallax representation unit to render the image, shifting the pixel defined in the color map. The color representation unit uses the normal map that maintains normals to the surface of the object for each pixel to change the way that light impinges on the surface and represent the roughness accordingly. A shadow representation unit uses a horizon map, which maintains information for each pixel to indicate whether a shadow is cast depending on the angle relative to the light source, so as to shadow the image rendered by the color representation unit.