Abstract: An improved method and system for storage of geographic data on physical storage media. The geographic data are stored in a manner that facilitates and enhances use and access of the data by various navigation application functions in navigation systems that use the data. The geographic data includes a parcelization that separates the geographic data into parcels having less than or equal to a maximum parcel size but having at least a desired fill percentage. The parcelization method also provides for a division arrangement that facilitates addressing and identification of the parcels. According to a further aspect, the geographic data includes special nodal entities that are used to collapse complex intersections, such as roundabouts, cloverleaves, and divided highways, into simpler data representations. The special nodal entities are associated with road segment data entities and used in a route calculation program in place of regular node entities.

Abstract: A navigation system uses a geographic database to determine a solution route to a destination and provides detailed maneuvering guidance for following the solution route. In addition, the navigation system includes a preview function that provides a summary of the solution route prior to providing the detailed maneuvering guidance for following the solution route. The preview function is included in the programming of the navigation system. The preview function uses a feature incorporated in the geographic database wherein the portion of the geographic database used by the navigation system when determining a solution route includes references to another portion of the database that includes the actual text of the names of the roads represented thereby.

Abstract: An architecture for a geographic database that supports the identification and use of names for intersections of roads located in a geographic region, and methods for use and formation thereof. The geographic database includes data that represent components of a road network in a geographic region. The geographic database includes a first plurality of data entities each of which represents an intersection of roads in the road network and a second plurality of data entities each of which represents a name of one of the components of the road network. The geographic database includes a third plurality of data entities each of which associates one of the first plurality of data entities with one of the second plurality of data entities.

Abstract: An improved method and system that provides for a data access interface layer in a navigation system. The navigation system is of the type that includes a navigation application software program that provides navigating features to a user of the system and a geographic database stored on a computer-readable storage medium wherein the geographical database includes information relating to the geographical region about which the navigation system provides the navigation features to the user. The data access interface layer is preferably stored in the navigation system as a library of software functions. The data access interface layer operates in conjunction with the navigation system application software. The data access interface layer isolates the navigation application software from the geographic data which are stored on the storage medium. The data access interface layer intercepts requests by the navigation application software for geographic data.

Abstract: A navigation system uses a geographic database to determine a solution route to a destination and provides detailed maneuvering guidance for following the solution route. In addition, the navigation system includes a preview function that provides a summary of the solution route prior to providing the detailed maneuvering guidance for following the solution route. The preview function is included in the programming of the navigation system. The preview function uses a feature incorporated in the geographic database wherein the portion of the geographic database used by the navigation system when determining a solution route includes references to another portion of the database that includes the actual text of the names of the roads represented thereby.

Abstract: A geographic database for use with a navigation application program that provides navigation features to an end-user. The geographic database includes a plurality of data records of a first type and a plurality of data records of a second type. The plurality of records of the first type are organized into a plurality of parcels, each of which includes a plurality of data records of the first type and the plurality of records of the second type are organized into a plurality of parcels, each of which includes a plurality of data records of the second type. The parcels of data records of the first type are interleaved with the parcels of data records of the second type. This interleaving enables navigation functions that use these different types to access these different types more quickly and efficiently, thereby enhancing navigation system performance.

Abstract: A method and system for supporting alternative names of geographic locations with a navigation application program that uses a geographic database stored on a computer-readable medium. The alternative names of geographic locations include names in a plurality of different languages. Included are one or more language filters. Each of the one or more language filters associates the data records in the geographic database that are used as names for geographic locations with one or more of the plurality of different languages. A routine uses the one or more language filters so that the navigation application program can use names for geographic locations that are valid in an access language selected from among the plurality of different languages.

Abstract: An improved method and system that provides for a data access interface layer in a navigation system. The navigation system is of the type that includes a navigation application software program that provides navigating features to a user of the system and a geographic database stored on a computer-readable storage medium wherein the geographical database includes information relating to the geographical region about which the navigation system provides the navigation features to the user. The data access interface layer is preferably stored in the navigation system as a library of software functions. The data access interface layer operates in conjunction with the navigation system application software. The data access interface layer isolates the navigation application software from the geographic data which are stored on the storage medium. The data access interface layer intercepts requests by the navigation application software for geographic data.

Abstract: A geographic database for use with a navigation application program that provides navigation features to an end-user. The geographic database includes data entities that represent segments of roads and additionally includes data entities that represent aggregations of segments of roads. The data entities that represent aggregations of segments of roads are used during a route calculation by the navigation application to suppress evaluation of roads of lesser functional rank thereby enhancing performance of the navigation system. According to one aspect, each of the data entities that represent segments of roads that represents a segment of a road that together with at least one other segment of a road forms part of an aggregation which is represented by one of the data entities that represent aggregations of segments of roads includes a reference thereto.

Abstract: A system and method for storing data in a computer-readable database to represent curved geographic features. The database can be used in a navigation system. A computable function is used to define a curved line that represents the curved geographic feature. The computable function may be a polynomial equation whose shape is defined by its coefficients. In one embodiment, the polynomial equation is a type of spline curve, in particular a Bezier curve whose shape is defined by control points. The coefficients of the polynomial equation are associated with data representing the curved geographic feature. In the case in which the polynomial equation is a Bezier curve, the control points for generating the Bezier curve are associated with the data representing the curved geographic feature. These control points are stored in the database and are used in displaying the curved geographic feature.

Abstract: A system and method for arranging and storing a plurality of records of geographic data, wherein each record corresponds to a physical feature having a physical location in a geographic region. The method and system comprise arranging the records of geographic data into a plurality of parcels. Each parcel includes records of geographic data that represent features having physical locations encompassed within a corresponding associated rectangular area located in the geographic region. The size and location of each such rectangular area associated with a parcel is determined by a series of divisions of a bounding rectangle that encompasses all of the features represented by the plurality of records into further rectangular areas. Each division, subsequent to an initial division, is made on a rectangular area resulting from the preceding division.

Abstract: An improved method and system for storage of geographic data on physical storage media. The geographic data are stored in a manner that facilitates and enhances use and access of the data by various navigation application functions in navigation systems that use the data. The geographic data includes a parcelization that separates the geographic data into parcels having less than or equal to a maximum parcel size but having at least a desired fill percentage. The parcelization method also provides for a division arrangement that facilitates addressing and identification of the parcels. According to a further aspect, the geographic data includes special nodal entities that are used to collapse complex intersections, such as roundabouts, cloverleaves, and divided highways, into simpler data representations. The special nodal entities are associated with road segment data entities and used in a route calculation program in place of regular node entities.

Abstract: A system and method for making and using a geographic database. The geographic database represents a geographic region and is used with a navigation application program. The geographic database includes a plurality of data entities each of which represents a physical feature in the geographic region. The plurality of data entities are separated into a plurality of parcels each of which contains a grouping of data entities that represent features in the geographic area encompassed within a separate one of a plurality of rectangles which together encompass all the features in the entire geographic region represented by all of the plurality of data entities. Each of the plurality of data entities has a data entity ID.