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This option helps you to fine-tune fluid-object collisions, e.g. when particles go though a surface, and visualizes how RealFlow | Cinema 4D "sees" and objects. The helper mesh is updated when you change one parameters of the the "Collision" or "Volume" parameters from the → "Properties" panel. If tags. If the collision geometry is not visible reset the scene to frame 0 or scrub the timeline.
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