Computer Science Department
School of Computer Science, Carnegie Mellon University
Smoke Sheets and Vortex Filaments
Smoke is one of the core phenomena which fluid simulation techniques in computer graphics have attempted to capture. Its behavior is well understood mathematically, and accurate smoke simulation can greatly enhance the realism of computer generated effects. In an attempt to overcome the diffusion inherent to Eulerian grid-based simulators, a technique has recently been developed which represents velocity using a sparse set of vortex filaments. This has the advantage of providing an easily understandable and controllable model for fluid velocity, but is computationally expensive because each filament affects the fluid velocity over the entire simulation space. We build upon previous work which merges adjacent rings of filaments by allowing filaments to form structures other than rings and developing a new set of reconnection criteria to take advantage of this generic filament graph. To complement this technique, we also introduce a method for smoke rendering designed to minimize the number of sample points without introducing excessive diffusion or blurring. This rendering technique advects a mesh representation of the smoke surface, thus effectively preserving the appearance of thin sheets and curls.