| 摘要 |
PURPOSE:To obtain a display device meeting positional information varied momentarily without relying on improvement in the performance of the device, by a method wherein map informa tion stored in a storage means are clipped precedently in a wider range than one wherein they are displayed in a display means. CONSTITUTION:A present position is inputted to a processing means 14 by a present position detecting means 11. Next, it is judged whether a range A wherein clipping is to be made precedently is included within a range B of map information stored in an internal storage means 15, and when the former is not included within the latter, map information containing the present position, which is stored in an external storage means 16, is read in the storage means 15. Then, it is judged whether a range C to be displayed in a display means 12 can be included in the range A, and when the former can not be included in the latter, clipping is made afresh precedently out of the map information (in the range B) stored in the storage means 15. Then, the direction of advance and a map rotation angle are determined from an output of the detecting means 11 by the processing means 14, rotation computation of map information within the range A is conducted, and clipping is made within the range C. Subsequently, the map information obtained by the processing means 16 is displayed 12 together with a sign indicating the present position and a sign indicating an azimuth. |
