Patent ID: 7457705
Filing Date: 2008-11-25
Classification: G01C

Abstract:
1. A navigation apparatus for displaying a three-dimensional terrain image based on a position and attitude of the navigation apparatus, comprises: a display unit having a display screen for displaying the three-dimensional terrain image; a position detection device which detects a current position of the navigation apparatus; an attitude detection device which detects a current attitude of the navigation apparatus; a geographic information storage device for storing three-dimensional terrain shape information; and an image creation unit for obtaining information that characterize a line-of-sight vector perpendicular to the display screen of the display unit, based on attitude information obtained by the attitude detection device, and creating the three-dimensional terrain image from a view point that is located along the line-of-sight vector, based on the current position detected by the position detection device, a line-of-sight defined by the line-of-sight vector, and three-dimensional terrain shape information stored in the geographic information storage device; wherein, when the attitude of the navigation apparatus is changed, the three-dimensional terrain image is updated according to the change of the attitude; and when an angle formed between the line-of-sight vector and a gravity vector is equal to or less than a predetermined value, height of the viewpoint of the three-dimensional terrain image for display on the screen is made higher than the height of the current position of the navigation apparatus as detected by position detection device.