This shader allows rendering of atmospheric effects such as fog and smoke. The shader interacts with all lighting elements of the scene (environment, area lights, directional lights, mesh lights, etc...) and will be part of any Deep EXR file produced by the render. The parameters of this shaders have been designed to allow an artist-friendly specification of atmosphere's look. The colour dialled in the UI will be the colour of the atmosphere. The often used absorption and scattering quantities provide counter intuitive parametrization and force the specification of colours unrelated to the final look of the render. Still, absorption and scattering are computed under the hood for a physically correct render. Specifies the presence of the atmosphere. Density is related to the amount of particles/molecules that block light. Increasing density makes objects disappear with distance. Density is also related to the scale of the scene. Scenes of a small scale need a higher Density to render the same effect as scene built using a larger scale. It is usual to plug a noise pattern into this parameter to obtain visually compelling effects. This gives the general color of the atmosphere. In physical terms, albedo specifies the ratio of reflected and absorbed light. In this particular parametrization, it allows the artist to select the colour that will be prevalent in the atmosphere. This shader allows the specification of volumes with an Albedo higher than 1 (maximum range is 2). This enables rendering of volumes witch are "super-reflective" while absorbing no light. For example it is possible to obtain dense halos around light sources while avoiding the steep absorption that makes all the objects invisible in the atmosphere. This non-physical behaviour gives more artistitic freedom.3Delight Atmosphere Parameters
Parameter Description Density Albedo
Overview
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