Navigation apparatus, and data processing method and computer program used therewith

A data processing method for displaying navigation information generated based on map information, the data processing method comprising:

• acquiring positional information;
• calculating altitudes of points on a route based on node-based altitude data;
• calculating an altitude of a navigation apparatus based on the positional information and based on the node-based altitude data;
• calculating an altitude of a vehicle having the navigation apparatus based on the positional information and the node-based altitude data;
• calculating altitudes of interpolation points on the route based on interpolation-point-based altitude data comprising interpolation points set between two adjacent nodes;
• excluding from the interpolation points one of a first sequential interpolation point and a second sequential interpolation point when a difference between altitude information of the first sequential interpolation point and altitude information of the second sequential interpolation point is less than or equal to a predetermined threshold difference;
• generating three-dimensional display information for a guidance region based on the positional information, the three-dimensional display information being obtained in observation from a camera viewpoint set within an allowable range for setting the camera viewpoint, the allowable range having altitudes not less than the altitude of the vehicle or the altitude of the navigation apparatus;
• and
• displaying the three-dimensional display information.

A computer-readable medium comprising instructions which, when executed by a processor, perform a method for displaying navigation information generated based on map information, the method comprising:

• acquiring positional information;
• calculating altitudes of points on a route based on node-based altitude data;
• calculating an altitude of a navigation apparatus based on the positional information and based on the node-based altitude data;
• calculating an altitude of a vehicle having the navigation apparatus based on the positional information and the node-based altitude data;
• calculating altitudes of interpolation points on the route based on interpolation-point-based altitude data comprising interpolation points set between two adjacent nodes;
• excluding from the interpolation points one of a first sequential interpolation point and a second sequential interpolation point when a difference between altitude information of the first sequential interpolation point and altitude information of the second sequential interpolation point is less than or equal to a predetermined threshold difference;
• generating three-dimensional display information for a guidance region based on the positional information, the three-dimensional display information being obtained in observation from a camera viewpoint set within an allowable range for setting the camera viewpoint, the allowable range having altitudes not less than the altitude of the vehicle or the altitude of the navigation apparatus;
• and
• displaying the three-dimensional display information.

A navigation apparatus for displaying navigation information generated based on map information, the navigation apparatus comprising:

• an input for acquiring positional information;
• a memory that stores two-dimensional map data, three-dimensional graphic data, and node-based altitude data of recorded altitude data of nodes which are set on a link used as a route;
• a data processor for:
• calculating altitudes of points on the route based on the node-based altitude data;
• calculating an altitude of the navigation apparatus based on the positional information and based on the node-based altitude data;
• calculating an altitude of a vehicle having the navigation apparatus based on the positional information and the node-based altitude data;
• generating three-dimensional route information for a guidance region based on the positional information;
• and
• generating three-dimensional data obtained in observation from a camera viewpoint set within an allowable range for setting the camera viewpoint, the allowable range having altitudes not less than the altitude of the vehicle or the altitude of the navigation apparatus;
• and
• a display device for displaying the three dimensional route information and the three-dimensional data, wherein
• the memory:
• stores, as interpolation-point-based altitude data, altitude information of interpolation points set between two adjacent nodes, and
• excludes one of a first sequential interpolation point and a second sequential interpolation point when a difference between altitude information of the first sequential interpolation point and altitude information of the second sequential interpolation point is less than or equal to a predetermined threshold difference.