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One of the most common errors with particle-object interaction is interpenetration. In this case, particles can pass through a solid object and become isolated from the rest of the fluid. Such a behaviour is often related to “Collision distance”, substeps, scale and your object’s geometry. The following explanations do not only explain basic functionality, but also give you valuable tips on how to avoid these problems. Please keep in mind that RealFlow automatically adjusts “Collision distance” when scene scale becomes changed. You can see five parameters with little chessboard icons. These symbols indicate that you are able to load a RGB image map, representing different zones of friction or roughness, for example. RealFlow interprets the file's grey shades and translates them into values. This feature also makes use of UV coordinates, so please do not forget to relax the object’s UV before export. To import a map please right-click on the appropriate parameter and choose “Load texture”. A detailed description can be found below under “Mapped Parameters”
Collision distance
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