| 摘要 |
PROBLEM TO BE SOLVED: To prevent a user from being kept waiting long until the correct present position is visually recognizable on a map picture. SOLUTION: The map display control section 11 of a map display terminal 1, using map data already acquired in a map data storage section 7, draws a map picture of the periphery of the present position together with a present position mark following up the change of present position detected by a GPS receiving section 2, and displays them on a display section 3. In parallel with this operation, a map data acquisition processing section 9 discriminates, as occasion demands, whether there is a second mesh, neighboring to the second mesh including the present position and also in a front side of an advancing direction, whose map data has not been acquired in the map data storage section 7. When there is such a mesh, the map data acquisition processing section 9 requests an external map information distributing device 30 via the Internet 20 for the map data of the mesh whose map data has not be acquired, then receives the map data transmitted from the map information distributing device 30 and additionally stores in the map data storage section 7.
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