Image displaying system for interactively changing the positions of a view vector and a viewpoint in a 3-dimensional space

• US 5,325,472 A
• Filed: 04/12/1991
• Issued: 06/28/1994
• Est. Priority Date: 04/13/1990
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited 1006 OAZA Kadoma-Shi Osaka Japan
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Horiuchi, Kazu, Nishimura, Kenji, Nakase, Yoshimori
• Primary Examiner(s): Herndon, Heather R.
• Assistant Examiner(s): JANKUS, ALMIS R
• Application Number:
  US07/684,389
• Time in Patent Office: 1,173 Days
• Field of Search: 395/119, 395/120, 395/125-127, 395/129-132, 395/164
• US Class Current: 345/427
• CPC Class Codes: G06T 15/20 Perspective computation

Abstract

An image displaying system interactively changes the positions of the view vector and the viewpoint in the 3-dimensional space of a camera model which displays an object geometric model, constructed within a computer, on the screen in the computer assisted design (CAD) and science art simulation field. The user inputs the object point and the target point on the display screen showing the viewpoint and the view vector direction so as to effect the screen display of the scene with the positions of the view vector and the viewpoint in the 3-dimensional space of the camera model for displaying on the screen the object geometric model constructed within the computer. The scene with the viewpoint and the view vector direction being interactively changed is displayed on the screen.

Claims

1. An image displaying system comprising:

a geometric data memory for storing geometric data of a 3-dimensional object in a 3-dimensional coordinate world space;

a view vector memory for storing view vector information consisting of viewpoint data which specifies a viewpoint in the world space from which the object can be viewed and viewing direction data which specifies a direction from the viewpoint to a point to be viewed;

a screen position inputting means for interactively inputting an object point identifying a 2-dimensional position on a display screen;

a viewpoint position computing which computes an intersection of the geometric data read from the geometric memory with a ray originating at an existing viewpoint defined by the viewpoint data read from the view vector memory and passing through a point in the world space corresponding to the object point, so as to store the intersection in the view vector memory as the viewpoint data of a new viewpoint.

2. An image displaying system comprising:

a view vector memory for storing view vector information consisting of viewpoint data which specifies a viewpoint in a 3-dimensional coordinate world space from which a 3-dimensional object can be viewed and viewing direction data which specifies a direction from the viewpoint to a point to be viewed;

a screen position inputting for interactively inputting a target point identifying a 2-dimensional position on a display screen;

a viewing direction computer which computes 3-dimensional angle data specifying a new direction originating at the viewpoint form the target point inputted from the screen position inputting means, a screen base position indicating a 2-dimensional position on the display screen corresponding to a view reference point, viewpoint data read from the view vector memory, and 3-dimensional angle data indicating the existing viewing direction data read from the view vector memory, so as to store the computed 3-dimensional angle data in the view vector memory as the new viewing direction data.

3. An image displaying system comprising:

a geometric data memory for storing geometric data of a 3-dimensional object in a 3-dimensional coordinate world space;

a view vector memory for storing view vector information consisting of viewpoint data which specifies a viewpoint in the world space from which the object can be viewed and viewing direction data which specifies a direction from the viewpoint to a point to be viewed;

a screen position inputting means for interactively inputting an object point identifying a 2-dimensional position on a display screen and a target point identifying a 2-dimensional position on a display screen;

a viewpoint position computer which computes an intersection of the geometric data read from the geometric memory with a ray originating at an existing viewpoint defined by the viewpoint data read from the view vector memory and passing through a point in the world space corresponding to the object point, so as to store the intersection in the view vector memory as the viewpoint data of a new viewpoint;

a viewing direction computer which computes 3-dimensional angle data specifying a new direction originating at the viewpoint from the target point inputted from the screen position inputting means, a screen base position indicating a 2-dimensional position on the display screen corresponding to a view reference point, viewpoint data read from the view vector memory, and 3-dimensional angle data indicating the existing viewing direction data read from the view vector memory, so as to store the computed 3-dimensional angle data in the view vector memory as the new viewing direction data.

4. An image displaying system comprising:

a geometric data memory for storing geometric data of a 3-dimensional object in a 3-dimensional coordinate word space;

a view vector memory for storing view vector information consisting of viewpoint data which specifies a viewpoint in the world space from which the object can be viewed and viewing direction data which specifies a direction from the viewpoint to a point to be viewed;

a screen position inputting means for interactively inputting an object point identifying a 2-dimensional position on a display screen and a target point identifying a 2-dimensional position on a display screen;

an interpolated position computer which generates sampled target points identifying 2-dimensional positions on a display screen by sampling a curve interpolated from the target points inputted from the screen position inputting means;

a viewpoint position computer which computes an intersection of the geometric data read from the geometric memory with a ray originating at an existing viewpoint defined by the viewpoint data read from the view vector memory and passing through a point in the world space corresponding to the object point, so as to store the intersection in the view vector memory as the viewpoint data of a new viewpoint;

a viewing direction computer which computes 3-dimensional angle data specifying a new direction originating at the viewpoint from a sampled target point computed by the interpolated position computer, a screen base position indicating a 2-dimensional position on the display screen corresponding to a view reference point, viewpoint data read from the view vector memory, and 3-dimensional angle data indicating the existing viewing direction data read from the view vector memory, so as to store the computed 3-dimensional angle data in the view vector memory as the new viewing direction data.