SCALE SEPARATION IN HAIR DYNAMICS

• US 20110216070A1
• Filed: 03/04/2010
• Published: 09/08/2011
• Est. Priority Date: 03/04/2010
• Status: Active Grant

• Current Assignee: Pixar (The Walt Disney Company)
• Original Assignee: Pixar (The Walt Disney Company)
• Inventors: Anderson, John, Petrovic, Lena, Witkin, Andrew P.
• Granted Patent: US 9,098,944 B2
• Time in Patent Office: Days
• US Class Current: 345/442
• CPC Class Codes: G06T 11/203 Drawing of straight lines or curves
• CPC Class Codes: G06T 13/40 of characters, e.g. humans, animals or virtual beings
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects
• CPC Class Codes: G06T 19/00 Manipulating 3D models or images for computer graphics
• CPC Class Codes: G06T 2210/21 Collision detection, intersection
• CPC Class Codes: G06T 2219/2016 Rotation, translation, scaling

Abstract

Techniques are disclosed for accounting for features of computer-generated dynamic or simulation models being at different scales. Some examples of dynamic or simulation models may include models representing hair, fur, strings, vines, tails, or the like. In various embodiments, features at different scales in a complex dynamic or simulation model can be treated differently when rendered and/or simulated.

Claims

1. A computer-implement method for separating scale in computer-generated dynamic or simulation models, the method comprising:

receiving, at the computer system, information specifying a first pose of a curve model;

receiving, at the computer system, information specifying a second pose of the curve model;

determining, with a processor associated with the computer system, a difference between the first and second pose of curve model;

decomposing, with the processor associated with the computer system, the difference between the first and second pose of curve model into a plurality of scale separations;

weighting, with the processor associated with the computer system, each of the plurality of scale separations; and

storing information describing the weighted plurality of scale separations in a storage device associated with the computer system.

2. The method of claim 1 wherein decomposing, with the processor associated with the computer system, the difference between first and second pose of curve model into a plurality of scale separations comprises decomposing the difference using one or more filtering operations.

3. The method of claim 1 wherein decomposing, with the processor associated with the computer system, the difference between first and second pose of curve model into a plurality of scale separations comprises decomposing the difference into a plurality of scale separations for dynamic properties or properties used for simulation.

4. The method of claim 1 further comprising determining, with the processor associated with the computer system, one or more forces based on the weighted plurality of scale separations that move the second pose of the curve model toward the first pose of the curve model.

5. The method of claim 1 further comprising applying, with the processor associated with the computer system, one or more forces influenced by the weighted plurality of scale separations to move the second pose of the curve model toward the first pose of the curve model.

6. The method of claim 1 wherein the curve model represents hair.

7. A computer-readable storage medium storing code configured to direct one or more processors associated with one or more computer systems for separating scale in computer-generated dynamic or simulation models, the computer-readable storage medium comprising:

code for receiving information specifying a first pose of a curve model;

code for receiving information specifying a second pose of the curve model;

code for determining a difference between the first and second pose of curve model;

code for decomposing the difference between the first and second pose of curve model into a plurality of scale separations;

code for weighting each of the plurality of scale separations; and

code for storing information describing the weighted plurality of scale separations.

8. The computer-readable storage medium of claim 7 wherein the code for decomposing the difference between first and second pose of curve model into a plurality of scale separations comprises code for decomposing the difference using one or more filtering operations.

9. The computer-readable storage medium of claim 7 wherein the code for decomposing the difference between first and second pose of curve model into a plurality of scale separations comprises code for decomposing the difference into a plurality of scale separations for dynamic properties or properties used for simulation.

10. The computer-readable storage medium of claim 7 further comprising code for determining one or more forces based on the weighted plurality of scale separations that move the second pose of the curve model toward the first pose of the curve model.

11. The computer-readable storage medium of claim 7 further comprising code for applying one or more forces influenced by the weighted plurality of scale separations to move the second pose of the curve model toward the first pose of the curve model.

12. The computer-readable storage medium of claim 7 wherein the curve model represents hair.

13. A method for simplifying handling of bulk properties in a distributed computing environment, the method comprising:

receiving, at one or more computer systems, information specifying a reference pose for each of a plurality of dynamic or simulation models;

determining, with one or more processors associated with the one or more computer systems, interaction eligibility for parts of a simulation in the distributed computing environment of the plurality of dynamic or simulation models based on the reference pose of each of the plurality of dynamic or simulation models; and

storing information indicative of the interaction eligibility in a storage device associated with the one or more computer systems.

14. The method of claim 13 wherein determining, with the one or more processors associated with the one or more computer systems, interaction eligibility for parts of a simulation in the distributed computing environment of the plurality of dynamic or simulation models comprises determining a positional difference between the reference pose of each dynamic or simulation model in a first set of dynamic or simulation models in the plurality of dynamic or simulation models and the reference pose of each dynamic or simulation model in a second set of dynamic or simulation models in the plurality of dynamic or simulation models.

15. The method of claim 13 wherein determining, with one or more processors associated with the one or more computer systems, interaction eligibility for parts of a simulation in the distributed computing environment of the plurality of dynamic or simulation models comprises determining a likelihood based on the reference pose of each dynamic or simulation model that a first set of curve models in the plurality of dynamic or simulation models will interact with a second set of curve models in the plurality of dynamic or simulation models.

16. The method of claim 13 further comprising:

generating, with the one or more processors associated with the one or more computer systems, information specifying processor assignments in the distributed computing environment based on the interaction eligibility.

17. The method of claim 13 further comprising:

detecting, with one or more processors associated with one or more computer systems in the distributed computing environment, collisions based on the interaction eligibility.

18. The method of claim 13 wherein the plurality of dynamic or simulation models represent hair or cloth.

19. A computer-readable storage medium comprising computer-executable code for implementing the method of claim 13.

20. A method for designing computer-generated hair models, the method comprising:

generating, with one or more processors associated with one or more computer systems associated with a simulation-assisted hair modeling environment, first information configured to display a hair style of a computer-generated hair model within one or more user interfaces associated with the simulation-assisted hair modeling environment;

communicating the first information to a display device;

receiving, at the one or more computer systems associated with the simulation-assisted hair modeling environment, a series of changes provided via the one or more user interfaces, each change in the series of changes authoring modifications to the hair style of the computer-generated hair model; and

in response to each change in the series of changes,

receiving, at the one or more computer systems associated with the simulation-assisted hair modeling environment, simulation results corresponding to the authored change,

generating, with the one or more processors associated with the one or more computer systems, second information configured to display the hair style according to the simulations results corresponding to the authored change, and

communicating the second information to a display device.

21. A computer-readable storage medium storing code configured to direct one or more processors associated with one or more computer systems for designing computer-generated hair models, the computer-readable storage medium comprising:

code for generating first information configured to display a hair style of a computer-generated hair model within one or more user interfaces associated with a simulation-assisted hair modeling environment;

code for receiving a series of changes provided via the one or more user interfaces, each change in the series of changes authoring modifications to the hair style of the computer-generated hair model; and

code for receiving, in response to each change in the series of changes, simulation results corresponding to the authored change; and

code for generating information configured to display the hair style according to the simulations results corresponding to each authored change.