ABSTRACT
This chapter presents volumetric fog, a technique developed at Ubisoft Montreal for Microsoft Xbox One, Sony Playstation 4, and PCs and used in Assassin’s Creed 4: Black Flag. We propose a novel, real-time, analytical model for calculating various atmospheric phenomena. We address the problem of unifying and calculating in a coherent and optimal way various atmospheric effects related to atmospheric scattering, such as
• fog with varying participating media density, • smoke and haze, • crepuscular rays or light shafts, • volumetric lighting and shadows. This chapter provides a brief introduction to a light-scattering model that
includes effects of in-and out-scattering and the Beer-Lambert law. We also describe how scattering can be computed and integrated numerically.
