Method and apparatus for searching a route

Claim 1

A method for searching for an optimum route between two arbitrarily specified points on road network data, said method comprising: dividing the road network data into a plurality of road network areas; obtaining, in advance, routes between each of the plurality of road network areas obtained in said dividing the road network data, and recording the obtained routes as route data into a route recording medium; investigating, when a starting point and a destination are specified, to obtain two road network areas from the plurality of road network areas to which the starting point and the destination respectively belong; retrieving the route data which corresponds to a combination of the two road network areas obtained in said investigating from the route recording medium; searching for a route from the starting point to the destination on a basis of the route data retrieved in said retrieving the route data and presenting the searched route to a user; and producing map data for displaying a background and recording the map data into a map recording medium; wherein, in said searching for the route, the map data corresponding to the route data retrieved in said retrieving the route data is read from the map recording medium and displayed, and the searched route is displayed over the displayed map data; and wherein, in the map data, a plurality of partial map data required when displaying a route between two road network areas are collected together in advance for each combination of the road network areas, and the plurality of collected partial map data are recorded in the map recording medium in an interrelated manner so that the data can be read by a single access operation.

Claim 2

A method for searching for an optimum route between two arbitrarily specified points on road network data, said method comprising: dividing the road network data into a plurality of road network areas; obtaining, in advance, routes between each of the plurality of road network areas obtained in said dividing the road network data, and recording the obtained routes as route data into a route recording medium; investigating, when a starting point and a destination are specified, to obtain two road network areas from the plurality of road network areas to which the starting point and the destination respectively belong; retrieving the route data which corresponds to a combination of the two road network areas obtained in said investigating from the route recording medium; searching for a route from the starting point to the destination on a basis of the route data retrieved in said retrieving the route data and presenting the searched route to a user; and producing map data for displaying a background and recording the map data into a map recording medium; wherein, in said searching for the route, the map data corresponding to the route data retrieved in said retrieving the route data is read from the map recording medium and displayed, and the searched route is displayed over the displayed map data; and wherein, in the map data, a plurality of partial map data required when displaying a route between two road network areas are collected together in advance for each combination of the road network areas, and the plurality of collected partial map data are recorded in the map recording medium in an interrelated manner so that the data can be read by a single access operation.

Claim 3

A method for searching for an optimum route between two arbitrarily specified points on road network data, said method comprising: dividing the road network data into a plurality of road network areas; obtaining, in advance, routes between each of the plurality of road network areas obtained in said dividing the road network data, and recording the obtained routes as route data into a route recording medium; investigating, when a starting point and a destination are specified, to obtain two road network areas from the plurality of road network areas to which the starting point and the destination respectively belong; retrieving the route data which corresponds to a combination of the two road network areas obtained in said investigating from the route recording medium; and searching for a route from the starting point to the destination on a basis of the route data retrieved in said retrieving the route data and presenting the searched route to a user; wherein said searching for the route further comprises: searching, in a vicinity of the starting point, for a first connecting route from the starting point to the route in the route data retrieved in said retrieving the route data on the basis of the road network data; searching, in a vicinity of the destination, for a second connecting route from the destination to the route in the route data retrieved in said retrieving the route data on the basis of the road network data; producing an entire route from the starting point to the destination by using the first and second connecting routes searched for in said searching for the first connecting route and said searching for the second connecting route and the route in the route data retrieved from said retrieving the route data; and displaying the entire route produced in said producing the entire route.

Claim 4

A method for searching for an optimum route between two arbitrarily specified points on road network data, said method comprising: dividing the road network data into a plurality of road network areas; obtaining, in advance, routes between each of the plurality of road network areas obtained in said dividing the road network data, and recording the obtained routes as route data into a route recording medium; investigating, when a starting point and a destination are specified, to obtain two road network areas from the plurality of road network areas to which the starting point and the destination respectively belong; retrieving the route data which corresponds to a combination of the two road network areas obtained in said investigating from the route recording medium; and searching for a route from the starting point to the destination on a basis of the route data retrieved in said retrieving the route data and presenting the searched route to a user; wherein said searching for the route further comprises: searching, in a vicinity of the starting point, for a first connecting route from the starting point to the route in the route data retrieved in said retrieving the route data on the basis of the road network data; searching, in a vicinity of the destination, for a second connecting route from the destination to the route in the route data retrieved in said retrieving the route data on the basis of the road network data; producing an entire route from the starting point to the destination by using the first and second connecting routes searched for in said searching for the first connecting route and said searching for the second connecting route and the route in the route data retrieved from said retrieving the route data; and displaying the entire route produced in said producing the entire route.

Claim 6

A method for searching for an optimum route between two arbitrarily specified points on road network data, said method comprising: dividing the road network data into a plurality of road network areas; obtaining, in advance, routes between each of the plurality of road network areas obtained in said dividing the road network data, and recording the obtained routes as route data into a route recording medium; investigating, when a starting point and a destination are specified, to obtain two road network areas from the plurality of road network areas to which the starting point and the destination respectively belong; retrieving the route data which corresponds to a combination of the two road network areas obtained in said investigating from the route recording medium; and searching for a route from the starting point to the destination on a basis of the route data retrieved in said retrieving the route data and presenting the searched route to a user; wherein, in said obtaining routes, at least one route is obtained between the road network areas and the obtained routes are recorded as the route data into the route recording medium; and wherein said searching for the route further comprises: displaying the at least one obtained route on the basis of the route data retrieved in said retrieving the route data; selecting, when the at least one obtained route is displayed in said displaying, one of the obtained routes in response to an operation by the user; searching for a first connecting route from the starting point to the route selected in said selecting one of the obtained routes in a vicinity of the starting point on a basis of the road network data; searching for a second connecting route from the destination to the route selected in said selecting one of the obtained routes in a vicinity of the destination on a basis of the road network data; and producing an entire route from the starting point to the destination by using the first and second connecting routes searched for in said searching for a first connecting route and said searching for a second connecting route and the route selected in said selecting one of the obtained routes.

Claim 7

A method for searching for an optimum route between two arbitrarily specified points on road network data, said method comprising: dividing the road network data into a plurality of road network areas; obtaining, in advance, routes between each of the plurality of road network areas obtained in said dividing the road network data, and recording the obtained routes as route data into a route recording medium; investigating, when a starting point and a destination are specified, to obtain two road network areas from the plurality of road network areas to which the starting point and the destination respectively belong; retrieving the route data which corresponds to a combination of the two road network areas obtained in said investigating from the route recording medium; and searching for a route from the starting point to the destination on a basis of the route data retrieved in said retrieving the route data and presenting the searched route to a user; wherein, in said obtaining routes, at least one route is obtained between the road network areas and the obtained routes are recorded as the route data into the route recording medium; and wherein said searching for the route further comprises: displaying the at least one obtained route on the basis of the route data retrieved in said retrieving the route data; selecting, when the at least one obtained route is displayed in said displaying, one of the obtained routes in response to an operation by the user; searching for a first connecting route from the starting point to the route selected in said selecting one of the obtained routes in a vicinity of the starting point on a basis of the road network data; searching for a second connecting route from the destination to the route selected in said selecting one of the obtained routes in a vicinity of the destination on a basis of the road network data; and producing an entire route from the starting point to the destination by using the first and second connecting routes searched for in said searching for a first connecting route and said searching for a second connecting route and the route selected in said selecting one of the obtained routes.

Claim 10

A method for searching for an optimum route between two arbitrarily specified points on road network data, said method comprising: dividing the road network data into a plurality of road network areas; obtaining, in advance, routes between each of the plurality of road network areas obtained in said dividing the road network data, and recording the obtained routes as route data into a route recording medium; investigating, when a starting point and a destination are specified, to obtain two road network areas from the plurality of road network areas to which the starting point and the destination respectively belong; retrieving the route data which corresponds to a combination of the two road network areas obtained in said investigating from the route recording medium; and searching for a route from the starting point to the destination on a basis of the route data retrieved in said retrieving the route data and presenting the searched route to a user; wherein said dividing the road network data further comprises: dividing the road network data into road network areas of minimum-units; and dividing the road network data into road network areas of collective units each including a plurality of the minimum-units; wherein said obtaining routes comprises: searching for two of the minimum-unit road network areas as a target; obtaining, when the distance between the minimum-unit road network areas searched for in said searching for two of the minimum-unit road network areas is shorter than a predetermined distance, a route between the searched minimum-unit road network areas and recording the obtained route as the route data into the route recording medium; and obtaining, when the distance between the minimum-unit road network areas searched for in said searching for two of the minimum-unit road network areas is longer than a predetermined distance, a route between the collective-unit road network areas to which the searched minimum-unit road network areas belong, and recording the obtained route and the route data into the route recording medium; wherein said searching for two of the minimum-unit road network areas, said obtaining a route between the searched minimum-unit road network areas, and said obtaining a route between the collective-unit road network areas are repeatedly performed; and wherein said investigating to obtain two road network areas further comprises: investigating, when the distance between the starting point and the destination is shorter than the predetermined distance, to obtain the minimum-unit road network areas to which the starting point and the destination belongs; and investigating, when the distance between the starting point and the destination is longer than the predetermined distance, to obtain the collective-unit road network areas to which the starting point and the destination belongs.

Claim 11

A method for searching for an optimum route between two arbitrarily specified points on road network data, said method comprising: dividing the road network data into a plurality of road network areas; obtaining, in advance, routes between each of the plurality of road network areas obtained in said dividing the road network data, and recording the obtained routes as route data into a route recording medium; investigating, when a starting point and a destination are specified, to obtain two road network areas from the plurality of road network areas to which the starting point and the destination respectively belong; retrieving the route data which corresponds to a combination of the two road network areas obtained in said investigating from the route recording medium; and searching for a route from the starting point to the destination on a basis of the route data retrieved in said retrieving the route data and presenting the searched route to a user; wherein said dividing the road network data further comprises: dividing the road network data into road network areas of minimum-units; and dividing the road network data into road network areas of collective units each including a plurality of the minimum-units; wherein said obtaining routes comprises: searching for two of the minimum-unit road network areas as a target; obtaining, when the distance between the minimum-unit road network areas searched for in said searching for two of the minimum-unit road network areas is shorter than a predetermined distance, a route between the searched minimum-unit road network areas and recording the obtained route as the route data into the route recording medium; and obtaining, when the distance between the minimum-unit road network areas searched for in said searching for two of the minimum-unit road network areas is longer than a predetermined distance, a route between the collective-unit road network areas to which the searched minimum-unit road network areas belong, and recording the obtained route and the route data into the route recording medium; wherein said searching for two of the minimum-unit road network areas, said obtaining a route between the searched minimum-unit road network areas, and said obtaining a route between the collective-unit road network areas are repeatedly performed; and wherein said investigating to obtain two road network areas further comprises: investigating, when the distance between the starting point and the destination is shorter than the predetermined distance, to obtain the minimum-unit road network areas to which the starting point and the destination belongs; and investigating, when the distance between the starting point and the destination is longer than the predetermined distance, to obtain the collective-unit road network areas to which the starting point and the destination belongs.