A material point method for snow simulation

Abstract

Snow is a challenging natural phenomenon to visually simulate. While the graphics community has previously considered accumulation and rendering of snow, animation of snow dynamics has not been fully addressed. Additionally, existing techniques for solids and fluids have difficulty producing convincing snow results. Specifically, wet or dense snow that has both solid- and fluid-like properties is difficult to handle. Consequently, this paper presents a novel snow simulation method utilizing a user-controllable elasto-plastic constitutive model integrated with a hybrid Eulerian/Lagrangian Material Point Method. The method is continuum based and its hybrid nature allows us to use a regular Cartesian grid to automate treatment of self-collision and fracture. It also naturally allows us to derive a grid-based semi-implicit integration scheme that has conditioning independent of the number of Lagrangian particles. We demonstrate the power of our method with a variety of snow phenomena including complex character interactions.

Animation of crack propagation by means of an extended multi-body solver for the material point method

“…It was later introduced to computer graphics by Stomakhin et al (2013) with their work on snow. Ram et al (2015) and Yue et al (2015) modified their method to simulate viscoplastic materials like foam.…”

“…1. We follow closely the implementation by Stomakhin et al (2013), with the exception that we use an explicit time step integration scheme to simplify the grid update.…”

“…We use the PIC/FLIP blend ratio α = 0.95 for all our simulations (see e.g., Stomakhin et al (2013) for an explanation of α). The grids must be aligned to allow for comparisons between grid values of different bodies, i.e., m k bi and m k di must refer to the masses of body b and d respectively at the same world space coordinate.…”

MPM Based Simulation for Various Solid Deformation

“…Stomakin et al [12] used MPM for simulating snow, and introduced a novel MPM method for heat transport, melting and solidifying materials [13]. Jiang et al [7] tuned the model in [12] to simulate granular materials.…”

“…Stomakin et al [12] used MPM for simulating snow, and introduced a novel MPM method for heat transport, melting and solidifying materials [13]. Jiang et al [7] tuned the model in [12] to simulate granular materials. Later Klár et al [8] introduced the Drucker-Prager plastic flow model into MPM to simulate sand dynamics, and Daviet et al [5] presented a semi-implicit scheme for granular materials.…”