Volume-preserving smoothing brush

Patent metadata

Field	Value
Publication number	US-9830743-B2
Application number	US-201213438797-A
Country	US
Kind code	B2
Filing date	Apr 3, 2012
Priority date	Apr 3, 2012
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

A system and method are disclosed for implementing a volume-preserving mesh smoothing brush. The volume-preserving mesh smoothing brush first computes modified positions of vertices of a 3D mesh. A change in the volume of the region of the 3D mesh smoothed by the volume-preserving mesh smoothing brush is estimated. Then updated positions of the vertices are computed based on the estimated change in the volume. The volume-preserving mesh smoothing brush effectively rounds the brushed area. During each smoothing iteration, the positions of the vertices are updated to smooth the 3D mesh while also approximately preserving the volume of the 3D mesh.

First claim

What is claimed is:

1. A method for smoothing a three-dimensional (3D) mesh, the method comprising:
identifying a set of vertices within an area of the 3D mesh that is operated on by a volume-preserving mesh smoothing brush that is configured to smooth the 3D mesh;
for each vertex in the set of vertices, computing a modified position based on the operation of the volume-preserving mesh smoothing brush, and computing a length of a Laplacian vector corresponding to the modified position computed for the vertex;
computing, for the set of vertices, an average length based on the lengths of the Laplacian vectors computed for the vertices in the set of vertices;
estimating a change in volume of the 3D mesh based on the modified positions computed for the vertices in the set of vertices;
computing, for each vertex in the set of vertices, an updated position of the vertex based on the modified position computed for the vertex, the average length computed for the set of vertices, and the estimated change in volume of the 3D mesh; and
inflating the 3D mesh based on the updated positions of the vertices, wherein the volume of the 3D mesh after being inflated is substantially the same as the volume of the 3D mesh before being operated on by the volume-preserving mesh smoothing brush.

2. The method of claim 1 , wherein computing an updated position of a vertex is based on an estimated normal vector of the vertex at the modified position computed for the vertex.

3. The method of claim 1 , wherein computing an updated position of a vertex is based on a fixed inflation strength parameter specified for the volume-preserving mesh smoothing brush.

4. The method of claim 1 , wherein computing an updated position of a vertex is based on a falloff function that defines how strongly the volume-preserving mesh smoothing brush affects the vertex and that is specified for the volume-preserving mesh smoothing brush.

5. The method of claim 1 , wherein computing the updated position of a vertex is based on a fixed smoothing rate parameter specified for the volume-preserving mesh smoothing brush.

6. A non-transitory computer-readable storage medium containing a program for smoothing a three-dimensional (3D) mesh, which, when executed by a processing unit, cause a computer system to perform an operation comprising:
identifying a set of vertices within an area of the 3D mesh that is operated on by a volume-preserving mesh smoothing brush that is configured to smooth the 3D mesh within a brush area of the volume-preserving mesh smoothing brush;
for each vertex in the set of vertices, computing a modified position based on the operation of the volume-preserving mesh smoothing brush;
estimating a change in volume of the 3D mesh based on the modified positions computed for the set of vertices;
computing, for each vertex in the set of vertices, an updated position of the vertex based on the modified position computed for the vertex and a product of an inflation strength and a falloff function that is based on the estimated change in volume of the 3D mesh and defines how strongly the volume-preserving mesh smoothing brush affects the vertex; and
inflating the 3D mesh based on the updated positions of the vertices, wherein the volume of the 3D mesh after being inflated is substantially the same as the volume of the 3D mesh before being operated on by the volume-preserving mesh smoothing brush.

7. The non-transitory computer-readable storage medium of claim 6 , further comprising:
for each vertex in the set of vertices, computing a length of a Laplacian vector corresponding to the modified position computed for the vertex; and
computing, for the set of vertices, an average length based on the lengths of the Laplacian vector computed for the vertices in the set of vertices.

8. The non-transitory computer-readable storage medium of claim 7 , wherein computing an updated position of a vertex is based on the average length computed for the set of vertices.

9. The non-transitory computer-readable storage medium of claim 6 , wherein computing the updated position of the vertex is based on an estimated normal vector of the vertex at the modified position computed for the vertex.

10. The non-transitory computer-readable storage medium of claim 6 , wherein computing the updated position of the vertex is based on a fixed smoothing rate parameter specified for the volume-preserving mesh smoothing brush.

11. A system for smoothing a three-dimensional (3D) mesh, the system comprising:
a processor; and
a memory coupled to the processor, wherein the memory includes an application program that includes instructions that, when executed by the processor, cause the processor to:
identify a set of vertices within an area of the 3D mesh that is operated on by a volume-preserving mesh smoothing brush that is configured to smooth the 3D mesh within a brush area of the volume-preserving mesh smoothing brush;
for each vertex in the set of vertices, compute a modified position based on the operation of the volume-preserving mesh smoothing brush;
estimate a change in volume of the 3D mesh based on the modified positions computed for the set of vertices;
compute, for each vertex in the set of vertices, an updated position of the vertex based on the modified position computed for the vertex and a product of an inflation strength and a falloff function that is based on the estimated change in volume of the 3D mesh and defines how strongly the volume-preserving mesh smoothing brush affects the vertex; and
inflate the 3D mesh based on the updated positions of the vertices, wherein the volume of the 3D mesh after being inflated is substantially the same as the volume of the 3D mesh before being operated on by the volume-preserving mesh smoothing brush.

12. The system of claim 11 , wherein the application program includes further instructions that when executed by the processor, cause the processor to:
for each vertex in the set of vertices, compute a length of a Laplacian vector corresponding to the modified position computed for the vertex; and
compute, for the set of vertices, an average length based on the lengths of the Laplacian vector computed for the vertices in the set of vertices.

13. The system of claim 12 , wherein computing an updated position of a vertex is based on the average length computed for the set of vertices.

14. The system of claim 11 , wherein computing an updated position of a vertex is based on an estimated normal vector of the vertex at the modified position.

15. The system of claim 11 , further comprising a display device configured to display the 3D mesh, a graphical representation of the volume-preserving mesh smoothing brush, and the smoothed 3D mesh.

16. The computer-implemented method of claim 1 , further comprising receiving input from an end-user indicating a smoothing operation to perform with the volume-preserving mesh smoothing brush on the 3D mesh.

17. The non-transitory computer-readable medium of claim 6 , further comprising the steps of receiving input from an end-user indicating a smoothing operation to perform with the volume-preserving mesh smoothing brush on the 3D mesh.

18. The system of claim 11 , wherein the application program includes further instructions that when executed by the processor, cause the processor to receive input from an end-user indicating a smoothing operation to perform with the volume-preserving mesh smoothing brush on the 3D mesh.

19. The method of claim 1 , wherein inflating the 3D mesh comprises causing each vertex i

Assignees

• Schmidt Ryan Michael
• Autodesk Inc

Inventors

• Schmidt Ryan Michael

Classifications

• G06T17/20 Primary

  Finite element generation, e.g. wire-frame surface description, {tesselation} · CPC title

• G06T19/20

  Editing of three-dimensional [3D] images, e.g. changing shapes or colours, aligning objects or positioning parts · CPC title

• G06T2219/2021

  Shape modification · CPC title