Simple Divergence-Free Fields for Artistic Simulation

We discuss tools for calculating divergence-free fields for artistic particle simulations. We introduce a simple, fast divergence-free noise function which can be used for turbulence. We also describe how the interpolation technique used by the noise function can be used for calculating artist-controlled divergence-free fields. The artist can create realistic unbounded flow fields without the complexity or memory cost of voxel-grid methods. CR Categories: I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling Physically based modeling.