Here Every Maya object has a "RealFlow | Maya" section in the "Attribute Editor", and here you control how RealFlow | Maya "sees" an object and how it will be filled with particles.
Add Collider
When you click on this button RealFlow | Maya will add a → "Collider" element to the object, where it is possible to define the object's physical properties like friction, stickiness, or bounciness.
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