Patent ID: 7493212

Claim:
An abridged map generating apparatus, comprising: an abridged map generation unit that generates an abridged map in which a shape of a road is simplified based upon road map data that specifies the shape of the road by shapes of links set for each predetermined road section, by simplifying a share of a link or link series with fixed positions of both end points of the link or link series made by lining up a plurality of the links; a point selection unit that selects some point set in advance upon the link; a line segment setting unit that sets a plurality of second line segments which connect between the point selected by the point selection unit and each of both the end points in order; a direction revision unit that revises directions of each of the second line segments set by the line segment setting unit, so that each angle which is formed between each of the second line segments and a predetermined direction set in advance becomes an integer multiple of an unit angle set in advance; an intersection point detection unit that obtains a point of intersection on which respective prolonged line segments obtained by prolonging the second line segments of which the direction has been revised by the direction revision unit are intersected each other; and a length revision unit that revises a length of each of the second line segments, so as to connect together the point of intersection obtained by the intersection point detection unit and one of the end points or one of the points selected by the point selection unit; and wherein: the abridged map generation unit generates the abridged map by simplifying the shape of the link or link series, by using each of the second line segments of which the length are revised by the length revision unit.