Graphic data processing system

• US 5,945,976 A
• Filed: 12/10/1996
• Issued: 08/31/1999
• Est. Priority Date: 11/14/1991
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Iwamura, Kazuaki, Kurihara, Tsuneya, Fujita, Takehiro
• Primary Examiner(s): Chow, Dennis-Doon
• Application Number:
  US08/762,997
• Time in Patent Office: 994 Days
• Field of Search: 345/419-427, 345/139, 382/285, 340/990, 340/995
• US Class Current: 345/419
• CPC Class Codes: G06F 3/04812 Interaction techniques based on cursor appearance or behaviour, e.g. being affected by the presence of displayed objects
• CPC Class Codes: G06F 3/04815 Interaction with a metaphor-based environment or interaction object displayed as three-dimensional, e.g. changing the user viewpoint with respect to the environment or object
• CPC Class Codes: G09G 5/00 Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators image data processing or generation, in general G06T
• CPC Class Codes: G09G 5/14 Display of multiple viewports

Abstract

This invention relates to a graphic data processing system, and is more particularly directed to provide an easy-to-operate system and displaying method thereof, for generating scene data from map data and retrieving and displaying attributes containing guide information of ground objects in a scene. In the first place, when a visual point is directed from above to below, a planar map is displayed, and as the visual point shifts in a horizontal direction, a three-dimensional scene image is generated and displayed from a map. Secondly, a three-dimensional window is displayed in a display, and graphic data is displayed inside the window.

Claims

1. A graphic data processing system for displaying a scene, comprising:

means for retrieving vector map data;

means for generating scene data from the retrieved vector map data;

means for projecting and displaying the generated scene data on a two-dimensional plane determined by position and direction of a visual point;

means for changing the position or direction of said visual point; and

means for selecting a display method which displays said scene data by the use of the said scene data display means on the basis of a changed visual point without displaying said vector map data in place of said scene data when said visual point is changed from a vertical direction to a horizontal direction by the use of said visual point change means, and a display method which displays said vector map data in place of said scene data on said display means when said visual point is changed from a horizontal direction to a vertical direction by the use of said visual point change means.

2. A graphic data processing system for displaying a scene, according to claim 1, wherein said display selection means generates said scene data from said vector map data and displays said scene data when an angle θ

between the direction of said visual point and the perpendicular is within a specific range |θ

|>

θ

th, and displays said vector map data in place of said scene data when θ

is within a specific range |θ

|≦

θ

th.

3. A graphic data processing system for displaying a scene, according to claim 1, which further comprises:

means for displaying an indication cursor inside the scene and changing a direction of said cursor; and

means for pointing a ground object in a three-dimensional space by retrieving ground object data which first crosses the direction of said indication cursor by the use of said vector map data.

4. A graphic data processing system for displaying a scene, according to claim 3, which further comprises:

means for retrieving attribute data added to said ground object data and linked with said vector map data;

means for checking interference of two objects; and

means for displaying a window of a rectangle or a rectangular parallelepiped more preferentially than a scene as the background by said interference check means, and displaying at least one of attribute data of two-dimensional media and attribute data of three-dimensional graphic media such as a document and an image on said window inside said display means by the use of said retrieved attribute data.

5. A graphic data processing system for displaying a scene, according to claim 4, which further comprises:

means for calculating an area for displaying said window, and displaying said window in such a manner that said window does not completely hide ground object data having the attribute data to be displayed inside said window.

6. A graphic data processing system for displaying a scene, according to claim 5, which further comprises:

means for retrieving another ground object data hiding the ground object data having the attribute to be displayed in the scene, switching the display of said another ground object data from solid display to wire frame display, and judging a display method of a ground object in the scene, so as to make the ground object data having the attribute more easily watchable.

7. A graphic data processing system for displaying a scene, according to claim 6, which further comprises:

means for effecting interference calculation for said object subjected to said solid display but not effecting interference calculation for said object subjected to said wire frame display, inhibiting an indication cursor to pass through said object subjected to said solid display but allowing said indication cursor to pass through said object subjected to said wire frame display, and thus switching the interference calculation with said indication cursor depending on said wire frame display and said solid display.

8. A graphic data processing system for displaying a scene, according to claim 7, which further comprises:

means for retrieving a route by the use of said road map data; and

means for moving said indication cursor in an area corresponding to a route in the scene in accordance with a predetermined pitch, retrieving attribute data of ground object data having said attribute data added thereto when said ground object data enters a predetermined range with said indication cursor being the center, displaying said attribute data in said window, and moving said indication cursor along the resulting route in the scene.

9. A graphic data processing system for displaying a scene, according to claim 8, which further comprises:

means for generating a pattern having the same shape as that of said indication cursor at a position of said scene corresponding to a junction between said calculated route and another road, erasing said indication cursor, that has been used so far, when said indication cursor points said shape pattern, using said pointed new shape pattern as a new indication cursor, retrieving a new route lest the route retrieved immediately before is not selected as such, and moving and guiding said new indication cursor along the resulting new route.

10. A graphic data processing system for displaying a scene, according to claim 8, which further comprises:

means for executing simulation when any disaster occurs, indicating an evacuation guide route obtained as a result of simulation by said indication cursor, and effecting disaster simulation such as the spread of a fire, flood, etc, on said vector map data to highlight ground objects in the direction of disaster by a color different from the color of other ground objects.

11. A display method of a visual map comprising the steps of:

retrieving vector map data;

generating scene data from said vector map data retrieved, projecting said scene data generated on a two-dimensional plane determined by a position of a visual point and its direction, and displaying said scene data;

changing the position or direction of said visual point; and

selecting a display method which displays said scene data on the basis of a changed visual point without displaying said vector map data in place of said scene data when said visual point is changed from a perpendicular direction to a horizontal direction, and a display method which displays said vector map data in place of said scene data when said visual point is changed from the horizontal direction to the perpendicular direction.