This presentation was given at SIGGRAPH 2023, which was held 28 July – 1 August 2024 in Denver, USA. Author: Chris Lewin.
Watch the presentation above and download the paper below.
A Position-Based Material Point Method
It's well understood that game physics simulations have to execute quickly, but the most difficult requirement is actually the stability of the simulation. Game physics simulations must operate completely autonomously, and usually, the player has some kind of input into the simulation, which can potentially be quite violent. This severely constrains the methods that we can use.
The explicit Material Point Method (MPM) is an easily implemented scheme for simulating a wide variety of different physical materials. However, it has well-known stability issues.
We have implemented a novel semi-implicit compliant constraint formulation of MPM that is stable at any time-step while remaining as easy to implement as an explicit integrator. We call this method Position Based MPM (PB-MPM). This work significantly improves the utility of MPM for real-time applications.
Open source code is available on GitHub along with a web-based demo: https://github.com/electronicarts/pbmpm