ROAD MAP DATA RECORDING METHOD AND NAVIGATION DEVICE

摘要

PROBLEM TO BE SOLVED: To renew road map data by adding a new road while maintaining the speed performance of the route search and route display of a navigation device. SOLUTION: For the road map data which are made hierarchical, the range of link ID numbers of individual links of the bottom layer 1 is set to 1000 to 1099. For multiple links which have connection relation and the same properties, successive link ID numbers, e.g. 1000 to 1099 and 1100 to 1199 are set. Even when a link is newly added and original links are divided, the succession of the link ID number like 1200 to 1249 and 1250 to 1299 can be maintained and the speed performance of the route search and route display can be maintained.