A Survey on Homogeneous Participating Media Rendering

Participating media are frequent in real-world scenes, whether it is milk, fruit juices, oil or muddy water in river or ocean scenes. Incoming light interacts with these participating media in complex ways: refraction at the boundaries and scattering and absorption inside the volumes. The radiative transfer equation is key point to solve this problem. There are several categories of the rendering methods which are all based on radiative transfer equation, but with different solutions. In this paper, we introduce these groups, more specifically, including: volume density estimation based approaches, virtual point / ray / beams lights, point-based approaches, Monte Carlo based approaches, acceleration techniques, accurate single scattering methods, neural network based methods and spatially-correlated participating media related methods. We discuss these methods, the challenges and open problems in this research direction.