An analytical approach to single scattering for anisotropic media and light distributions
Vincent Pegoraro, Mathias Schott, Steven G. Parker · 2009
Despite their numerous applications, efficiently rendering partici-pating media remains a challenging task due to the intricacy of the radiative transport equation. While numerical techniques remain the method of choice for addressing complex problems, a closed-form solution to the air-light integral in optically thin isotropic media was recently derived. In this paper, we extend this work and present a novel analytical approach to single scattering from point light sources in homogeneous media. We propose a combined formulation of the air-light integral which allows both anisotropic phase functions and light distributions to be adequately handled. The technique relies neither on precomputation nor on storage, and we provide a robust and efficient implementation allowing for an explicit control on the accuracy of the results. Finally, the per-formance characteristics of the method on graphics hardware are evaluated and demonstrate its suitability to real-time applications.