high performance computing on graphics processing units: hgpu.org

Realistic rain scenes animation is a complex task due to both the rendering and fluid dynamics simulation issues. The associated phenomena, like rain strokes rendering, splashing of raindrops and the simulation of the generated surface flow are known difficulties in this area. This paper describes a computational framework to incorporate these elements in a scene containing a digital terrain model (DTM). In the rain model, the raindrops are modeled by a particle system implemented in GPU. Each particle represents a drop and the Precomputed Radiance Transfer (PRT), expressed in a spherical harmonics bases, is used to incorporate environment lightning to the rendering engine. The Smoothed Particle Hydrodynamics (SPH) method is employed for simulating the superficial flow over the terrain and lake formations. The rendering of the fluid free surface is performed by applying an environment mapping technique plus Fresnel effects to a regular geometric representation known as "carpet". The experimental results show the potential of the proposed pipeline for computer graphics and highlight the fact that it is a promising framework for real time applications.