When a user indicates a portion of a map to be enlarged or contracted, a surface generating unit generates surfaces by gradually changing a surface from a first shape to a second shape, the first shape corresponding to a position of a map portion previousl...

In a map display device, a surface storing unit stores surface information which defines a curved surface having a form that depends on positions of portions of a map which are to be enlarged and/or contracted. A mapping unit maps the map onto the curved s...

This invention relates to map displaying system, in which the reference altitude value determining means obtains a reference altitude value in accordance with the altitude data in the specific area, and the altitude data changing means performs the process...