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In RealFlow texture maps are always square, regardless of their origin. Therefore this concept is also valid for foam maps. Whatever shape your grid fluid domain might have, the resulting texture map shares equal side lengths. For that reason there is only one value available. By default a foam map has a size of 256 x 256 pixel, but in most cases that is not enough. Very large texture maps might slow down RealFlow’s simulation process, because it takes some time to create and store them.
@ diffusion
Real foam shows areas of high and low concentration. Between these areas, foam flows in and out creating the typical patterns. “@ diffusion” simulates this process and in technical terms it is the rate per area unit at which foam moves between these zones.
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