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To see the objects at simulation time go to Fluid > Particles > Child Objects and disable "Render only". Be aware that disabling this option might increase simulation time.
Scattering and Random Instances
The "Random" parameters turn RealFlow | Cinema 4D into a powerful an easy-to-use scatterer. This way it is possible to randomize the render instances in terms of position, rotation, and scale. This is, for example, great for sand, gravel, or stony grounds.
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