ray tracing volume densities
This paper presents new algorithms to trace objects represented by densities within a volume grid, e.g. clouds, fog, flames, dust, particle systems. We develop the light scattering equations, discuss previous methods of solution, and present a new approximate solution to the full three-dimensional radiative scattering problem suitable for use in computer graphics. Additionally we review dynamical models for clouds used to make an animated movie.
ray tracing traces paper algorithm object grid clouds particle systems lighting light scattering method approximation use computer graphics review model simulation of natural phenomena stochastic modeling raster graphics radiative transport