Map displaying method and apparatus, and navigation system having the map displaying apparatus

A map display apparatus for displaying a map on a display device, being mounted on a moving object, comprising:

• a data reading-out portion for reading out map data representing a mesh area including a first point corresponding to a positional information inputted from outside, from a map database that stores map data;
• a viewpoint setting portion for determining a viewpoint at an objective height with respect to a second point based on a height of the first point and a height of the second point at a location a predetermined distance from the first point, and for determining a viewpoint at a predetermined height with respect to a third point, at a location a predetermined distance from the first point;
• and
• a display processing portion for performing a perspective transformation on the map data from the viewpoint and for displaying graphic data generated by the perspective transformation on the display device;
• wherein a mode of a mark representing said moving object is switched in accordance with a result whether the mark being displayed in the display apparatus in a superposing manner on the graphics data.

A map display apparatus for displaying a map on a display device, being mounted on a moving object, comprising:

• a data reading-out portion for reading out map data representing a three-dimensional map within a mesh area including a first point corresponding to a positional information inputted from outside, from a map database that stores said map data including height data and two-dimensional data within said mesh area;
• a viewpoint setting portion for determining a first viewpoint at an objective height with respect to a second point based on a height of the first point and a height of the second point at a location a predetermined distance form the first point, in a three-dimensional display mode, and for determining a second viewpoint at a predetermined height with respect to a third point, at a location a predetermined distance from the first point, in a pseudo three-dimensional display mode;
• and
• a display processing portion for performing a perspective transformation on the map data from the first viewpoint in said three-dimensional display mode and performing a perspective transformation on the two-dimensional data in the map data from the second viewpoint in said pseudo three-dimensional display mode, and for displaying graphic data generated by the perspective transformation on the display device;
• wherein a mode of a mark representing said moving object is switched in accordance with a result whether display mode is said three-dimensional display mode or said pseudo three-dimensional display mode, the mark being displayed in the display apparatus in a superposing manner on the graphics data.

A map display apparatus for displaying a map on a display device, being mounted on a moving object, comprising:

• a data reading-out portion for reading out map data representing a three-dimensional map within a mesh area including a first point corresponding to a positional information inputted from outside, from a map database that stores said map data;
• a viewpoint setting portion for determining a view point at an objecting height with respect to a second point, based on a height of the first point and a height of the second point at a location a predetermined distance from the first point;
• an input device for accepting an operation for changing said height of said viewpoint, said viewpoint setting portion changing said height of said viewpoint in response to said operation;
• a display processing portion for performing a perspective transformation the map data read out by the data reading-out portion from the viewpoint, and for displaying graphics data generated by the perspective transformation on the display device;
• wherein a mode of a mark representing said moving object is switched in accordance with said height of said viewpoint.