| 摘要 |
PROBLEM TO BE SOLVED: To allow coordinate value information to be utilized without using an accurate map image.SOLUTION: Coordinate values in a first coordinate system are associated with a plurality of areas in a map drawn by map image data. A relation between a coordinate value in the first coordinate system of each area and a coordinate value in a second coordinate value is stored. On reception of a coordinate value in the first coordinate system, an area associated with the coordinate value is specified, and the coordinate value in the first coordinate system of this area is converted to a coordinate value in the second coordinate system on the basis of the correspondence relation between the coordinate value in the first coordinate system and the coordinate value in the second coordinate system. Even with respect to maps like an illustrated map, the maps are partially accurately drawn in many cases because being drawn by reflecting actual positions, and each area has a tendency to be more accurate than the entire map. Therefore, a coordinate value indicating a more accurate position on the map can be obtained by using the correspondence relation of areas, and coordinate values can be handled even in the case of a map being not accurate. |
