AREA INFORMATION ACQUIRING APPARATUS, AREA INFORMATION ACQUISITION METHOD IN THE AREA INFORMATION ACQUIRING APPARATUS, AREA INFORMATION ACQUISITION PROGRAM, AREA INFORMATION SERVER DEVICE, AREA INFORMATION DISTRIBUTION METHOD IN THE AREA INFORMATION SERVER DEVICE, AND AREA INFORMATION DISTRIBUTION PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a user with area information by efficiently downloading the information, even if a route is changed during travel in a communication navigation system.;SOLUTION: An approximation curve calculating part 330 calculates an approximation curve 393, connecting a current location to a predetermined destination. A part 340 for calculating the rate of divergence selects, as a route point, a point on each of a plurality of routes from the current location to the destination, specifies as an approximation curve point, a point corresponding to each route point from the approximation curve 393; and calculates, as the rate of divergence, a distance for each route point between the route point and the approximation curve point which corresponds to the route point. A download priority calculating part 350 determines a priority point, based on the rate of divergence. An area information downloading part 360 downloads the area information on the priority point from a server device.;COPYRIGHT: (C)2010,JPO&INPIT