MaterialAware Mesh Deformations

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Material-Aware Mesh Deformations

• Tiberiu Popa Dan Julius Alla
  Sheffer
• Department of Computer Science, University of
  British Columbia

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Mesh Deformation

• Fine continuous control over stiffness
• Simple, intuitive interface
• Interactive rates

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Previous work Controlling stiffness

• No stiffness control
• Barr84 Sorkine et al. 04 Lipman et al.
  05 Yu 04 Zhou 05

• Skeletons binary control
• Capell et al. 02 Allen 02

• Physical Simulations
• James et al. 03

• Control of stiffness SIGGRAPH 2005
• James et al. 05 Sumner et al. 05

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Material Properties
user driven
data driven
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Material Properties

• Bending stiffness coefficients (edges)

• Shearing stiffness coefficients (faces)

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Deformation Metaphor

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Algorithm Overview
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Propagating Transformations

• Triangle transformations should be
• Continuous across the surface
• Consistent with material properties

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Propagating Transformations Example
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Propagating Transformations

• Use weighted combination of anchor transformations

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Finding the weights
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Algorithm Overview
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Vertex Positioning

• Adjust triangle transformations
• Adjacent triangles agree on vertices
• As close as possible to target transformations

• Direct distortion toward flexible areas

Sumner 04
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Algorithm Overview
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Example Results
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Anisotropic Materials

• The formulation uses two scalar fields to
  describe bending/shearing flexibility
• Flexibility could be a directional property (e.g.
  knee joint)

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Anisotropic Materials
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Material Learning
Original model
Sample poses
Derived Materials
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Data-driven Results
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Data-driven Refinements
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Results
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Results
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Results
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Summary

• Simple and powerful deformation tool
• Material properties
• Data-driven/user-driven materials
• Anisotropic materials

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• Thank you

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Propagating Transformations

• Use weighted combination of anchor transformations

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Propagating Transformations

• Our weights are barycentric coordinates with
  respect to the anchors

Alexa 02
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Mesh Deformation

• Fine continuous control over stiffness
• Simple, intuitive interface
• Interactive rates

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Mesh Deformation

• Fine continuous control over stiffness
• Simple, intuitive interface
• Interactive rates

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Example Results
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Algorithm Overview
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Anisotropic Materials
Isotropic propagation
Alexa 02
Anisotropic propagation
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Material Learning
1.
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3.
4.
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Material Learning
3.
4.
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Results
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Results