Patent ID: 6169552
Filing Date: 2001-01-02
Classification: G01C,G08G

Abstract:
A navigation device for displaying a three-dimensional map on a display frame, comprising: a map storage unit for storing three-dimensional data of plural map constituents which constitute the three-dimensional map; a vehicle position detecting unit for detecting a position of a vehicle in which the navigation device is installed; a view point determining unit for determining a view point on the basis of the position of the vehicle detected by the vehicle position detecting unit; and a map display unit for projecting a mark showing the position of the vehicle detected by the vehicle position detecting unit and each map constituent specified by the three-dimensional data stored in said map storage unit onto a plane from the view point determined by the view point determining unit, to form a three-dimensional bird's-eye view map, and displaying the three-dimensional bird's-eye view map on the display frame,wherein said map display unit includes: a hiding determining means for determining whether, in three dimensional space, the mark is hidden by a map constituent located nearer the viewpoint than the mark so that there is no direct line of sight between the view point and the mark and the mark is not normally displayed on the three-dimensional bird's-eye view map; and a projection mode changing means for automatically changing a projection mode of the mark or the map constituent so that the mark is displayed on the display frame even though the mark is not in a direct line of sight from the view point, wherein the projection mode is automatically changed only if the hiding determining means determines that the mark is hidden by the map constituent.