| 摘要 |
PURPOSE:To correctly set a search start point or a search end point in conformity with a user's desire when a route to a destination or a passing midway point is to be searched in a navigation apparatus which updates and displays a current position of a vehicle on a map screen as the vehicle runs. CONSTITUTION:A link L5 nearest to a point P0 designated by a user is selected, and sequentially traced to extract a node N3 of an intersection. If the node N3 is within a distance (r) from a point P1 which is a projected point of true point P0 on the link L5, the node N3 is set as a search point. If the node is not within the distance (r), one of the nodes N4 and N5 at both ends which is nearer to the node N3 and within the distance (r) is selected. If the nodes N4 and N5 are not present in the distance (r), a pseudo node is formed. In this manner, even when a distance between nodes is long, for example, in arm expressway, it is possible to search to a point proximate to the point P0 without a sense of incompatibility. |
