Ray tracing volume densities

James T. Kajiya, Brian P Von Herzen
1984 Computer graphics  
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.
doi:10.1145/964965.808594 fatcat:tkg2tsxrlrew5n3pg2xapjumke