Each foam particle can contribute a texture, similar to a wetmap where the fluid particles leave marks on a black canvas. There you also have several parameters to control dissipation and diffusion effects to make the particle marks vanish over time. With foam maps you have these options as well.
Calculate texture
This mode allows you to store a grayscale texture map for each simulated frame. Calculating a texture map is a computationally intensive process and should only be activated when you really need it. Activating this feature is only one half of the process. To store the maps this feature has to be activated under "Export Central". You can choose between five different image formats: BMP, JPG, PNG, TGA and TIF. If the selected format is capable of 16-bit (e.g. TIF), the texture will be saved as 16-bit grayscale, otherwise the 8-bit mode is used.
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