← ArchivePaper2020
Dynamic Deformables: Implementation and Production Practicalities
Course covering Pixar's Fizt simulator improvements for speed, robustness, and generality deployed across Coco, Cars 3, and Onward.
Abstract
Simulating dynamic deformation has been an integral component of Pixar's storytelling since Boo's shirt in Monsters, Inc. (2001). Recently, several key transformations have been applied to Pixar's core simulator Fizt that improve its speed, robustness, and generality. Starting with Coco (2017), improved collision detection and response were incorporated into the cloth solver, then with Cars 3 (2017) 3D solids were introduced, and in Onward (2020) clothing is allowed to interact with a character's body with two-way coupling. The 3D solids are based on a fast, compact, and powerful new formulation that we have published over the last few years at SIGGRAPH. Under this formulation, the construction and eigendecomposition of the force gradient, long considered the most onerous part of the implementation, becomes fast and simple. We provide a detailed, self-contained, and unified treatment here that is not available in the technical papers. This new formulation is only a starting point for creating a simulator that is up challenges of a production environment. One challenge is performance: we discuss our current best practices for accelerating system assembly and solver performance. Another challenge that requires considerable attention is robust collision detection and response.
How to read this
- Category
- Course / production practicalities (SIGGRAPH Courses)
- Contributions
- Documents improvements to Pixar's Fizt simulator for speed, robustness, and generality across Coco, Cars 3, and Onward
- Gives a detailed, self-contained, unified treatment of a new 3D-solids formulation that makes force-gradient construction and eigendecomposition fast and simple
- Shares best practices for accelerating system assembly and solver performance in a production environment
- Context
- Consolidates a line of SIGGRAPH elasticity work for character simulation, related to McAdams et al.'s 'Efficient Elasticity for Character Skinning with Contact and Collisions', into production-oriented guidance.Builds on: Efficient Elasticity for Character Skinning with Contact and Collisions
- Correctness
- Studio-grounded and pedagogical rather than a new evaluated result; the formulation is mathematically derived and the practices are production-proven across named films, so claims are about implementability and shipped robustness rather than benchmarked superiority.
- Clarity
- Highly accessible as a course; the self-contained derivation is its main value and rewards a careful read more than a paper would.
- How to read it
- Treat as a reference: read the eigendecomposition/force-gradient treatment closely, then dip into the performance best-practices sections as needed.
Built upon by
Related work
- Nonlinear Cloth Simulation with Isogeometric Analysis 2024 / CASA
- Clean Cloth Inputs: Removing Character Self-Intersections with Volume Simulation 2018 / SIGGRAPH
- Finding Hank 2016 / SIGGRAPH
- Robust Treatment of Collisions, Contact and Friction for Cloth Animation 2002 / SIGGRAPH
Keywords
This page summarises the entry and links to its original source. The archive never hosts or redistributes the publication itself.Show it in the full archive list →