libWetCloth

A Multi-Scale Model for Simulating Liquid-Fabric Interactions

ACM Transactions on Graphics (SIGGRAPH North America 2018)

Yun (Raymond) Fei, Columbia University
Christopher Batty, University of Waterloo
Eitan Grinspun and Changxi Zheng, Columbia University

Source Code, Data Assets & Houdini Projects
GitHub
Paper
Preprint: Original (21.0MB) | Reduced (2.4MB), Supplemental Document, ACM Digital Library, BibTex Citation, Selected as Back Cover
Video
, MP4, Two Minute Papers
Extra Video
Pour on Porous Plastic, Honey Dripping on Cloth
Presentation
Video, PowerPoint Slides
In Press
Deutschlandfunk (in German), Two Minute Papers, 3DVF (in French), Columbia Engineering, CGWorld (in Chinese)
The Wet Things Trilogy
libWetHair: A Multi-Scale Model for Simulating Liquid-Hair Interactions
libWetCloth: A Multi-Scale Model for Simulating Liquid-Fabric Interactions
CreamyStrand: A Multi-Scale Model for Coupling Strands with Shear Dependent Liquid
Thesis
Multi-Scale Models to Simulate Interactions between Liquid and Thin Structures

We propose a method for simulating the complex dynamics of partially and fully saturated woven and knit fabrics interacting with liquid, including the effects of buoyancy, nonlinear drag, pore (capillary) pressure, dripping, and convection-diffusion. Our model evolves the velocity fields of both the liquid and solid relying on mixture theory, as well as tracking a scalar saturation variable that affects the pore pressure forces in the fluid. We consider the porous microstructure implied by the fibers composing individual threads, and use it to derive homogenized drag and pore pressure models that faithfully reflect the anisotropy of fabrics. In addition to the bulk liquid and fabric motion, we derive a quasi-static flow model that accounts for liquid spreading within the fabric itself. Our implementation significantly extends standard numerical cloth and fluid models to support the diverse behaviors of wet fabric, and includes a numerical method tailored to cope with the challenging nonlinearities of the problem. We explore a range of fabric-water interactions to validate our model, including challenging animation scenarios involving splashing, wringing, and collisions with obstacles, along with qualitative comparisons against simple physical experiments.

GALLERY

ACKNOWLEDGMENTS

This work was supported in part by the National Science Foundation under Grant Nos.:1717178, 1319483, CAREER-1453101, the Natural Sciences and Engineering Research Council of Canada under Grant No. RGPIN-04360-2014, SoftBank Group, Pixar, and Adobe. We also thank Gilles Daviet and Peter Yichen Chen for insightful discussions, Chang Xiao, Henrique Maia and Oded Stein for their assistance, Gabriel Cirio for his cloth implementation, Xinxin Zhang for his AMGPCG pressure solver, Robert Lane and Jorge Espinoza for their help on storage and computational devices, and Cristin Barghiel and Julie Lottering for their continued generous contribution from SideFX.