Patent ID: 7783687

Claim:
A map data processing apparatus, comprising: a recording medium drive unit that reads out map data from a recording medium that contains the map data that includes map-related information related to a map; and a processing unit that executes map data processing based upon the map data read out by the recording medium drive unit, wherein: the map data includes a structure achieved by dividing the map into a plurality of mesh-like subdivisions and dividing the map-related information into units corresponding to the individual subdivisions, and a structure in which the map-related information is managed in units of subdivision sets each containing a plurality of adjacent subdivisions and the map-related information is used in the map data processing apparatus in units of the individual subdivision sets; the subdivision sets are each constituted with a core portion having at least one subdivision that does not overlap with another subdivision set and an overlap portion having at least one subdivision that is part of a core portion of another subdivision set; the map-related information is route-related information related to routes on the map used for route calculation; intersection points of road are designated as nodes; the route-related information comprises sets of subject node information each corresponding to one of a plurality of nodes present on each road and sets of adjacent node information corresponding to nodes connecting with individual subject nodes; the route-related information corresponding to the core portion comprises the subject node information and the adjacent node information; and the route-related information corresponding to the overlap portion is generated by eliminating the adjacent node information corresponding to specific nodes from the route-related information corresponding to the core portion.