Proximity and Interpenetration Depth Queries for Deformable Models

1. Proximity and Interpenetration Depth Queries for Deformable Models Presented by Alexandre Senecal Supervisor Paul Kry Summer 2009

2. Project description QuadNode Adaptively sampled distance fields Adaptively sampled gradient fields Gradient computations Deformations computations Metrics and analysis Future works Conclusions Questions Outline

3. Project Description • Limitations of adaptively sampled distance fields • Must be recomputed if geometry changes • Expensive to build • Not feasible for real time deformations • Solution • Approximate deformations to distance fields

4. QuadNode

5. Adaptively Sampled Distance Field

6. Adaptively Sampled Gradient Field Gradient = (Dist(p,alpha) – Dist(p, 0)) / alpha

7. Distance Functions • Inside/Outside • PQP • Should I expand???

8. Gradient Computations • Using Higher degrees, MacLaurin series??? • Possibly find the extent to which this approximation applies and where it becomes obsolete and we require a new ASDF.

9. Deformations Computations • Putting it all together • List of possible deformations • Least square method to adjust alpha parameters of deformations to avoid collisions • Can incrementally correct approximation with distance test a test site to adjust approximation?

10. Metrics and Analysis • Some nice figures and possibly a graph • Discuss advantages of our method • Frequency of tests and how fast can we update our model • How complex can the model be?

11. Future Works • Where we plan on taking this for december • Applications • Lip contacts in facial models • Finger pad contact • Etc..

12. Conclusion • Bah…

13. Questions? • End your presentation with a simple question slide to: • Invite your audience to ask questions • Provide a visual aid during question period • Avoid ending a presentation abruptly