Adaptive Particle Size Setting and Normal Calculation Methods in Fluid Rendering

In this paper, we present an adaptive particle size setting method in Lagrangian-approach based screen space splatting algorithm in real-time fluid rendering. The particle radius will be adjusted according to its Weber number and local density in the rendering process so that a large radius of peaceful fluid particle can help to eliminate a bumpy surface artifact, and a small radius can prevent obviously spherical shapes of particles in splash. We also propose an adaptive normal calculation method to avoid the numerical calculation errors in normal computation process. An adaptive sampling interval is set in accordance with the viewing distance from camera to the fluid so that fuzzy edges or double image effect in a fixed sampling interval normal computation process could be prevented. Both of the two approaches introduced in this paper take only small amount of computing time and will have little impact on the time consuming property of a real-time fluid rendering application.