Vortex particle smoke simulation with an octree data structure

We propose an octree-based presentation of vortex particles to simulate smoke and gaseous phenomena in a physical way. Vortex particle method prevails over grid-based method in terms of less numerical dissipation and more detail features, but it suffers from heavy computational overhead due to per-particle Biot-Savart integration over the entire simulation space. To alleviate this problem, we employ an octree background grid to separate the vortex particles into individual groups. Particles in groups are aggregated as a single super vortex particle to reduce computational cost. The proposed method produces comparable visual result as previous methods with much less computational overhead.