Particle–mesh coupling in the interaction of fluid and deformable bodies with screen space refraction rendering

On the basis of the smoothed particle hydrodynamics and finite element method (FEM) model, we propose a method integrating several improvements for the real-time simulation of fluid interacting with deformable bodies. We improve the particle neighbor search in smoothed particle hydrodynamics, so that the predefined scene containers are no longer needed. This improvement can also be applied to the simulation of fluid interacting with other materials, such as rigid and soft bodies. We also propose a two-way coupling method for fluid and deformable bodies, where the particle–mesh interaction is obtained by the ray-traced collision detection method instead of the proxy/ghost particle generation. By using the forward ray-tracing method for both velocity and position, we are able to calculate the coupling forces based on the conservation of momentum and kinetic energy in the particle–mesh interaction. We use the screen space fluid rendering for fluid, and on the basis of that, we introduce a screen space refraction rendering method to improve the refraction effect. We implement our method in NVIDIA CUDA and OptiX to make use of the full computational power of a graphics processing unit. The simulation results are analyzed and discussed to show the efficiency of our method.