Most of RealFlow's force-based daemons provide a falloff function for controlling how the force should vanish.
Creating a Rigid Body Setup
Let's create a basic falloff scenario with a simple rigid body dynamics scene. Here is the setup – the nodes can be added from the appropriate shelves:
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After a few moments you will see a → MultiBody consisting of 225 cubes:
- Delete the original cube.
- Rescale the MultiBody with the R key and make it an → active rigid body under Node Params > Node > Dynamics.
- Change the MultiBody's' mass under Node Params > Rigid body > @ density Density > 200
- A → “Gravity” daemon ties the cubes to the ground.
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The → “Attractor” daemon is placed in the scene's centre and uses the falloff – all parameters are located under “Node Params”:
- Attractor > Bounded > Yes
- Rescale the daemon's viewport gizmo with the R key and include all cubes.
- Attractor > Internal force > -200.0
- Make the force field visible under Display Force Field > Show field > Yes.
- All you can see is a green mess.
- Change this Get a better view with Display Force Field > @ magnitude scale > 0.005Magnitude scale
All arrows have exactly the same length, because the force is acting with the same strength at each point:
Activating the Falloff
Enable the daemon's falloff – all parameters located under Node Params > Force Field Falloff:
- Enable falloff > Yes
- @ Display falloff > Yes
- @ falloff Falloff bounds > Sphere
Now, the arrows have different lengths and you can see two spheres (circles in 2D):
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When you simulate you will recognize that the inner cubes are stronger affected than their counterparts near the daemon's boundary – this is the falloff's influence:
The falloff creates different zones of attraction (only the MultiBody is visible here).
- Change the MultiBody's “@ density” "Density” if necessary.
- Play with “@ falloff “Falloff percent” to change the size of the falloff zone.
- Set the “@ falloff “Falloff decay type” to “Quadratic” and “Cubic” and simulate again to see the difference.
- The arrows show you immediately how the forces change with different settings.
- Simulate.