| 摘要 |
PROBLEM TO BE SOLVED: To reduce the data size of a recording medium and to simplify the operation to set a destination. SOLUTION: On the basis of relative positions of respective points where running parts cross, out of crossings in which a plurality of roads cross, crossing point data on the respective points are provided regarding the crossings which are judged that the respective points do not belong to one crossing, and, regarding the crossings which are judged that the respective points belong to one crossing, crossing point data on one point out of the respective points is provided. Road data is provided with crossing point data on one point out of the respective points regarding the crossings which are judged that the respective points belong to one crossing. The number of the crossing point data can be reduced, and the data size of a recording medium can be reduced. Since one object data is displayed on a display screen regarding the same crossing, it is possible to simplify an operation which selects a prescribed crossing from a list to set a destination. |
