Real-Time Erosion Using Shallow Water Simulation

We present a new real-time hydraulic erosion simulation for Computer Graphics. In our system water runs over the surface and disintegrates the underlying layer of soil. The grit is simulated as a fluid with higher viscosity and moves on the ground of the water pool. When water evaporates, or the dissolved soil exceeds a critical level, the dissolved matter is deposited back on the ground for accumulation to occur. The grit motion as well as the water simulation are calculated by the shallow water simulation that is a 2D simplification of Navier-Stokes equations. This simulation has proven to be useful in many Computer Graphics applications because of the speed of calculation and the visual plausibility of the results. Our experiments show that the shallow water-based erosion is suitable for real-time simulation of a wide variety of phenomena including river and lake formation due to rain and evaporation, erosion of surfaces affected by a sudden splash of high level of water, mountain erosion, etc. The speed of simulation makes the algorithm suitable for real-time surface modeling and editing.