초록 ▼

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 include

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. Further, the geographic data include a normalized attribute array that includes reoccurring combinations of certain selected attributes of the geographic data. Indices to the array are included in place of data corresponding to the selected attributes. When a navigation application program requests data, an entry in the normalized attribute table pointed to by an index in the data is used to return the requested data in the particular combination of attributes from the normalized attribute array. The geographic data is compiled by a method that facilitates access to the data on a physical medium. According to the compilation method, data files to be stored on the medium are organized into parcels. The data records within the data files are identified by the parcel in which they are located. An arrangement of all the data files on the medium is determined and a parcel identification related to the medium is assigned to each parcel. Cross references between data records are updated to include the assigned parcel identifications and the parcels are stored on the medium.

대표청구항 ▼

[ We claim:] [1.] A method of storing a plurality of records of geographic data on a storage medium, wherein each record represents a physical feature having a physical location in a geographic region, the method comprising the steps of:separating said plurality of records into first and second grou

[ We claim:] [1.] A method of storing a plurality of records of geographic data on a storage medium, wherein each record represents a physical feature having a physical location in a geographic region, the method comprising the steps of:separating said plurality of records into first and second groupings of records wherein the records in said first of said groupings represent physical features having geographic locations encompassed within a first sub-rectangular area and the records in said second of said groupings represent physical features having geographic locations encompassed within a second sub-rectangular area,wherein said first and said second sub-rectangular areas are formed by a division at a position of a rectangular area that encompasses the locations of the physical features represented by the plurality of records in said first and second groupings, wherein said position of said division is determined byevaluating a plurality of trial divisions of said rectangular area; andselecting one of said plurality of trial divisions based upon resultant sizes of said first and second groupings.