Papers by Hayley Iben

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Artistic Simulation of Curly Hair

Hayley Iben, Mark Meyer, Lena Petrovic, Olivier Soares, John Anderson, Andrew Witkin
July 2013

Artistic simulation of hair presents many challenges - ranging from incorporating artistic control to dealing with extreme motions of characters. Additionally, in a production environment, the simulation needs to be fast and results need to be usable "out of the box" (without extensive parameter modifications) in order to produce ... more

Paper (PDF)

Additional materials: []

Available in the Proceedings of the Symposium on Computer Animation 2013.

Available as Pixar Technical Memo #12-03b

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Anisotropic Elasticity for Inversion-Safety and Element Rehabilitation

Theodore Kim, Fernando de Goes, Hayley Iben
July 2019

We present an analysis of anisotropic hyperelasticity, specifically transverse isotropy, that obtains closed-form expressions for the eigendecompositions of many common energies. We then use these to build fast and concise Newton implementations. We leverage our analysis in two separate applications. First, we show that existing anisotropic energies are not inversion-safe, ... more

Paper (PDF)


Additional materials: [Anisotropy2019_supplement.pdf], []

Holding the Shape in Hair Simulation

Hayley Iben, Jacob Brooks, Christopher Bolwyn
July 2019

Hair simulation models are based on physics, but require additional controls to achieve certain looks or art directions. A common simulation control is to use hard or soft constraints on the kinematic points provided by the articulation of the scalp or explicit rigging of the hair [Kaur et al. 2018; ... more

Paper (PDF)