Hi guys,

I have two RBD objects, floating on FLIP-fluid. I set the Density (mass) to 400 (lower than the fluid mass).

When two objects are of the same amount of mass, they have to react in the same way, right? I mean in this case, they have to stay on the surface.

The problem is the bigger object stays on the surface, but the smaller one sinks into the fluid:

- How can I fix it?
- How can I set the density(mass) in the SOP level (as an RBD source)?


Thanks for helping.

/obj/AutoDopNetwork/fliptank:gridscale 1.5

To be more specific this happens because Houdini doesn't have enough information to calculate the final buoyant force to defeat gravity.
If you increase sim resolution (reducing Particle Separation) you will get the proper result.
Another cheaper way is to only increase the collision resolution (reducing Collision Separation) portion of the sim itself.
You can find feedback force information under the impulse subsection of the feedback sub-data of each RBD object.
Hope it helps.