Methods and apparatus for invising objects in computer animation

• US 8,217,958 B1
• Filed: 05/25/2011
• Issued: 07/10/2012
• Est. Priority Date: 11/17/2006
• Status: Active Grant

• Current Assignee: Pixar (The Walt Disney Company)
• Original Assignee: Pixar (The Walt Disney Company)
• Inventors: Baraff, David, Fong, Michael, Waggoner, Christine
• Primary Examiner(s): Amini, Javid A
• Application Number:
  US13/115,708
• Time in Patent Office: 412 Days
• Field of Search: 345/589
• US Class Current: 345/589
• CPC Class Codes: G06T 13/20 3D [Three Dimensional] animation
• CPC Class Codes: G06T 2210/21 Collision detection, intersection

Abstract

A method for invising objects includes receiving information indicating an intersection between a first object and a second object. Visibility of the first object is modified based on the amount of interpenetration between the first object and the second object. A predetermined threshold may be received. The visibility of the first object may be reduced while the amount of the interpenetration fails to exceed the predetermined threshold. The first object may be made invisible when the predetermined threshold is exceeded.

Claims

1. A method for modifying visibility of objects in computer-generated scenes, the method comprising:

receiving, at one or more computer systems, information indicative of an intersection between a first object of a computer-generate scene and a second object of the computer-generated scene;

identifying, with one or more processors associated with the one or more computer systems, at least one a color property associated with of the first object in data representing the first object, the at least one color property of the first object assigned a first value in the data representing the first object and being an attribute of the first object influencing color of the first object when positioned in the computer generated-scene and being associated with a first value;

determining, with the one or more processors associated with the one or more computer systems, a second value to replace usage of the first value assigned to the at least one color property associated with of the first object in an operation on the first object based on an amount of interpenetration between the first object and the second object; and

generating, with the one or more processors associated with the one or more computer systems, information configured to modify visibility of the first object in the computer generated scene in the operation on the first object based on the second value for the at least one color property associated with the first object.

2. The method of claim 1 wherein determining, with the one or more processors associated with the one or more computer systems, the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object comprises determining the second value in response to a maximum penetration depth between the first object and the second object.

3. The method of claim 1 wherein determining, with the one or more processors associated with the one or more computer systems, the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object comprises:

determining a maximum distance inside of the second object of a plurality of points associated with the first object; and

determining a color value for each point in the plurality of points in response to the maximum distance inside the second object of the plurality of points.

4. The method of claim 1 wherein determining, with the one or more processors associated with the one or more computer systems, the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object comprises reducing the first value of the at least one color property associated with the first object in response to the amount of interpenetration when the amount of the interpenetration fails to exceeds a predetermined threshold.

5. The method of claim 4 further comprising:

invising the first object when the amount of the interpenetration exceeds the predetermined threshold.

6. The method of claim 1 wherein generating, with the one or more processors associated with the one or more computer systems, the information configured to modify visibility of the first object in the computer generated scene in the operation on the first object based on the second value for the at least one color property associated with the first object comprises generating information reducing the visibility of the first object in the computer-generated scene.

7. The method of claim 1 wherein identifying, with the one or more processors associated with the one or more computer systems, the at least one color property associated with of the first object in the data representing the first object comprises identifying a property associated with of the first object that specifies the color of the first object in the computer-generated scene as defined on the first object.

8. The method of claim 1 wherein identifying, with the one or more processors associated with the one or more computer systems, the at least one color property associated with of the first object in the data representing the first object comprises identifying a property associated with of the first object that specifies the color of the first object in the computer-generated scene as defined by one or more materials that form the first object.

9. The method of claim 1 wherein identifying, with the one or more processors associated with the one or more computer systems, the at least one color property associated with of the first object in the data representing the first object comprises identifying a transparency property associated with of the first object.

10. The method of claim 1 wherein determining, with the one or more processors associated with the one or more computer systems, the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object further comprises determining the second color responsive to color of the second object in the computer-generated scene.

11. The method of claim 1 wherein determining, with the one or more processors associated with the one or more computer systems, the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object further comprises determining the second color responsive to color of a background in the computer-generated scene.

12. A non-transitory computer-readable medium storing computer-executable code for modifying visibility of objects in computer-generated scenes, the non-transitory computer-readable medium comprising:

code for receiving information indicative of an intersection between a first object of a computer-generate scene and a second object of the computer-generated scene;

code for identifying at least one a color property associated with of the first object in data representing the first object, the at least one color property of the first object assigned a first value in the data representing the first object and being an attribute of the first object influencing color of the first object when positioned in the computer generated-scene and being associated with a first value;

code for determining a second value to replace usage of the first value assigned to the at least one color property associated with of the first object in an operation on the first object based on an amount of interpenetration between the first object and the second object; and

code for generating information configured to modify visibility of the first object in the computer generated scene in the operation on the first object based on the second value for the at least one color property associated with the first object.

13. The non-transitory computer-readable medium of claim 12 wherein the code for determining the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object, based on an amount of interpenetration between the first object and the second object comprises code for determining the second value in response to a maximum penetration depth between the first object and the second object.

14. The non-transitory computer-readable medium of claim 12 wherein the code for determining the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object comprises:

code for determining a maximum distance inside of the second object of a plurality of points associated with the first object; and

code for determining a color value for each point in the plurality of points in response to the maximum distance inside the second object of the plurality of points.

15. The non-transitory computer-readable medium of claim 12 wherein the code for determining the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object comprises code for reducing the first value of the at least one color property associated with the first object in response to the amount of interpenetration when the amount of the interpenetration fails to exceeds a predetermined threshold.

16. The non-transitory computer-readable medium of claim 15 further comprising:

code for invising the first object when the amount of the interpenetration exceeds the predetermined threshold.

17. The non-transitory computer-readable medium of claim 12 wherein the code for generating the information configured to modify visibility of the first object in the computer generated scene in the operation on the first object based on the second value for the at least one color property associated with the first object comprises code for generating information reducing the visibility of the first object in the computer-generated scene.

18. The non-transitory computer-readable medium of claim 12 wherein the code for identifying the at least one color property associated with of the first object in the data representing the first object comprises code for identifying a property associated with of the first object that specifies the color of the first object in the computer-generated scene as defined on the first object.

19. The non-transitory computer-readable medium of claim 12 wherein the code for identifying the at least one color property associated with of the first object in the data representing the first object comprises code for identifying a property associated with of the first object that specifies the color of the first object in the computer-generated scene as defined by one or more materials that form the first object.

20. The non-transitory computer-readable medium of claim 12 wherein the code for identifying the at least one color property associated with of the first object in the data representing the first object comprises code for identifying a transparency property associated with of the first object.

21. The non-transitory computer-readable medium of claim 12 wherein the code for determining the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object further comprises code for determining the second color responsive to color of the second object in the computer-generated scene.

22. The non-transitory computer-readable medium of claim 12 wherein the code for determining the second value to replace usage of the first value assigned to the at least one color property associated with of the first object in the operation on the first object based on an amount of interpenetration between the first object and the second object further comprises code for determining the second color responsive to color of a background in the computer-generated scene.

23. A method for rendering images of objects in computer-generated scenes in parallel, the method comprising:

receiving, at each of a plurality of computer systems, information indicative of an intersection at a unique time step of a computer animation between a first object and a second object;

modifying, at each computer system in the plurality of computer systems independently of another computer system in the plurality of computer systems with one or processors associated with the computer system, how at least one color property of the first object in data representing the first object is interpreted at the unique time step in response to an amount of interpenetration between the first object and the second object at the unique time step such that a resulting change in visibility of the first object at the unique time step due to how the modified at least one color property is interpreted at the unique time step is temporally coherent across the computer animation; and

generating, at each computer system in the plurality of computer systems with the one or processors associated with the computer system, an image of the computer animation at the unique time step reflecting the resulting change in the visibility of the first object at the unique time step.