Method and apparatus for changing the perspective view of a three-dimensional object image displayed on a display screen
First Claim
1. A method for rotating a perspective view of a three-dimensional object image displayed on a two-dimensional display screen, the perspective view of the three-dimensional object image being rotated from an original view point to a desired view point and a cursor indicating the desired view point on the display screen, the method comprising the steps of:
- instructing a rotation of the perspective view of the three-dimensional object image from the original view point to the desired view point, by moving the cursor to the desired view point on the display screen;
displaying a circle on the display screen, the circle overlapping the three-dimensional object image displayed on the display screen, the desired view point corresponding to a first point in the area of the circle;
displaying a line segment on the display screen, the line segment directed from the first point in the area of the circle to the center of the circle;
generating a hemisphere having a top surface and a circular bottom surface, the circumference of the bottom surface being the circle, where a second point on the top surface of the hemisphere represents the first point projected to the top surface of the hemisphere, the desired view point is a projection from the second point to the bottom surface of the hemisphere and the original view point is a projection from the vertex of the hemisphere; and
rotating the perspective view of the three-dimensional object image by changing the view point from the original view point to the desired view point.
1 Assignment
0 Petitions
Accused Products
Abstract
An apparatus and method for rotating a perspective view of a three-dimensional object image displayed on a display screen from an original view point to a desired view point, and for moving the perspective view in a parallel manner from the original view point to the desired view point. When the perspective view is rotated, a circle is generated that has a first point corresponding to the desired view point. A line segment is generated from the first point to the center of the circle. A hemisphere is generated that has a top surface, a vertex, and the circle as a bottom surface. A second point on the top surface represents the first point projected to the top surface. The desired view point is a projection from the second point to the bottom surface of the hemisphere and the original view point is a projection from the vertex of the hemisphere. The perspective view displayed on the display screen is then changed to the desired view point. When the perspective view is moved in a parallel manner, a boundary is generated which represents a displayable range of the three-dimensional object image on the display screen. A line segment is generated from the current cursor position to the center of the boundary. The displayed perspective view is changed by moving the perspective view along the line segment by a distance equal to the length of the line segment.
78 Citations
23 Claims
-
1. A method for rotating a perspective view of a three-dimensional object image displayed on a two-dimensional display screen, the perspective view of the three-dimensional object image being rotated from an original view point to a desired view point and a cursor indicating the desired view point on the display screen, the method comprising the steps of:
-
instructing a rotation of the perspective view of the three-dimensional object image from the original view point to the desired view point, by moving the cursor to the desired view point on the display screen; displaying a circle on the display screen, the circle overlapping the three-dimensional object image displayed on the display screen, the desired view point corresponding to a first point in the area of the circle; displaying a line segment on the display screen, the line segment directed from the first point in the area of the circle to the center of the circle; generating a hemisphere having a top surface and a circular bottom surface, the circumference of the bottom surface being the circle, where a second point on the top surface of the hemisphere represents the first point projected to the top surface of the hemisphere, the desired view point is a projection from the second point to the bottom surface of the hemisphere and the original view point is a projection from the vertex of the hemisphere; and rotating the perspective view of the three-dimensional object image by changing the view point from the original view point to the desired view point. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 22)
-
-
9. A method for displaying a perspective view of a three-dimensional object image on a display screen, the perspective view of the three-dimensional object image being rotated from an original view point to a desired view point and a cursor indicating a position on the display screen, the method comprising the steps of:
-
instructing a rotation of the perspective view of the three-dimensional image from the original view point to the desired view point on the display screen; displaying a circle on the display screen, the circle overlapping the three-dimensional object image, the circle having a radius which allows the entire circle to be displayed on the display screen, the desired view point corresponding to a first point in the area of the circle; displaying a line segment on the display screen, the line segment directed from the first point to the center of the circle; changing the direction, the length, and the displayable range of the line segment in accordance with the movement of the cursor; generating a hemisphere having a top surface and a circular bottom surface, the circumference of the bottom surface being the circle, where a second point on the top surface of the hemisphere represents the first point projected to the top surface of the hemisphere, the desired view point is a projection from the second point to the bottom surface of the hemisphere and the original view point is a projection from the vertex of the hemisphere; and displaying a perspective view of the three-dimensional object image on the display screen, as viewed from the desired view point. - View Dependent Claims (10, 11, 12, 13, 14, 15)
-
-
16. An apparatus for rotating a perspective view of a three-dimensional object image displayed on a two-dimensional display screen, the perspective view being rotated from an original view point to a desired view point, the apparatus comprising:
-
display means, comprising a two-dimensional display screen and a cursor which indicates the desired view point on the display screen, for displaying a perspective view of the three-dimensional object image corresponding to the original view point on the display screen; instructing means for instructing the apparatus, by moving the cursor to the desired view point on the display screen, to rotate the perspective view of the three-dimensional object image from the original view point to the desired view point; circle data generating means for determining, when an instruction to rotate the perspective view of the three-dimensional object image is made by the instructing means, a circle that overlaps the three-dimensional object image displayed on the display screen, the desired view point corresponding to a first point in the area of the circle, and for generating circle data which represents the circle, the display means displaying the circle represented by the circle data on the display screen; directional segment data generating means for determining, when an instruction to rotate the perspective view of the three-dimensional object image is made by the instructing means, a line segment directed from the first point in the area of the circle to the center of the circle, and for generating direction segment data which represents the line segment, the display means displaying the line segment represented by the direction segment data by overlapping the line segment with the circle and the three-dimensional object image; hemisphere data generating means for determining, when an instruction to rotate the perspective view of the three-dimensional object image is made by the instructing means, a hemisphere having a top surface, a vertex on the top surface and a circular bottom surface, the circumference of the bottom surface being the circle, and for generating hemisphere data representing the hemisphere, where a second point on the top surface of the hemisphere represents the first point in the area of the circle being projected to the top surface of the hemisphere, the desired view point is a projection from the second point to the bottom surface of the hemisphere and the original view point is a projection from the vertex of the hemisphere; and display control means for rotating the perspective view of the three-dimensional object image on the display screen by changing the view point from the original view point to the desired view point. - View Dependent Claims (17, 18, 19, 20, 21, 23)
-
Specification