Coupling water and smoke to thin deformable and rigid shells

We present a novel method for solid/fluid coupling that can treat infinitesimally thin solids modeled by a lower dimensional triangulated surface. Since classical solid/fluid coupling algorithms rasterize the solid body onto the fluid grid, an entirely new approach is required to treat thin objects that do not contain an interior region. Robust ray casting is used to augment a number of interpolation, finite difference and rendering techniques so that fluid does not leak through the triangulated surface. Moreover, we propose a technique for properly enforcing incompressibility so that fluid does not incorrectly compress (and appear to lose mass) near the triangulated surface. This allows for the robust interaction of cloth and shells with thin sheets of water. The proposed method works for both rigid body shells and for deformable manifolds such as cloth, and we present a two way coupling technique that allows the fluid's pressure to affect the solid. Examples illustrate that our method performs well, especially in the difficult case of water and cloth where it produces visually rich interactions between the particle level set method for treating the water/air interface and our newly proposed method for treating the solid/fluid interface. We have implemented the method on both uniform and adaptive octree grids.