Vehicle-route computing apparatus

A vehicle-route computing apparatus comprising:

• a road-map storing means for storing road maps for guiding a vehicle;
• a destination-area determining means for determining a destination area from a destination position toward which said vehicle is driven;
• a destination-area route network storing means for storing a plurality of destination-area route network data sets which are each associated with a destination area and obtained by calculating routes from a plurality of departure areas to said destination area in advance;
• and
• a route-search processing means for reading out one of said destination-area route network data sets associated with said destination area determined by said destination-area determining means from said destination-area route network storing means, searching said read-out destination-area route network data set for a guidance route from a departure position to said destination position of said vehicle in said destination area to which said vehicle is running and presenting said guidance route.

A vehicle-route computing apparatus comprising:

• a road-map storing means for storing road maps for guiding a vehicle;
• a departure-area determining means for determining a departure area of said vehicle;
• a destination-area determining means for determining a destination area from a destination position toward which said vehicle is driven;
• a departure-area route network storing means for storing a plurality of departure-area route network data sets which are each associated with a departure area and obtained by calculating routes from said departure area to a plurality of destination areas in advance;
• and
• a destination-area route network storing means for storing a plurality of destination-area route network data sets which are each associated with a destination area and obtained by calculating routes from a plurality of departure areas to said destination area in advance;
• a route-search processing means for reading out one of said departure-area route network data sets associated with said departure area determined by said departure-area determining means from said departure-area route network storing means and one of said destination-area route network data sets associated with said destination area determined by said destination-area determining means from said destination-area route network storing means, searching said read-out departure-area route network data set and said read-out destination-area route network data set for a guidance route from a departure position of said vehicle in said departure area to said destination position of said vehicle in said destination area to which said vehicle is running and presenting said guidance route.