Daemon Falloffs: Curves

Owned by thomas (Unlicensed)
Last updated: 29 Sept, 2016
3 min read

Most of RealFlow's force-based daemons provide a falloff function for controlling how the force should vanish. For this workflow example we will be using exactly the same setup from “Daemon Falloffs: Basics”. The only difference lies in the → “Attractor” daemon's “Force Field Falloff” settings:

Node Params > Force Field Falloff > falloff decay type > Custom shape




With this option you are now able to define a falloff curve:

  • Under “Falloff custom shape” you can see a blue default curve.

  • This curve describes the current falloff.

  • Click on “+” to open an editor.

Creating a Wave-Shaped Curve

In the first example we want to create a curve with ups and downs:

  • To add new points double click on the editor's canvas.
  • Drag them with the mouse until you get a curve similar to the one shown below.
  • Use the X and Y fields and sliders if you need exact values.

 

 

The horizontal X axis represents the falloff area (the area between the two yellow viewport spheres):

  • 0.0 (min) represents the falloff areas inner boundary.
  • 1.0 (max) is the falloff areas outer boundary.

The vertical Y axis is a force multiplier and determines the force's strength at a certain point.

  • 0.0 (min) means that the resulting force will be 0.0 as well.
  • 1.0 (max) means that the resulting force is equal to the daemon's strength value.

 

With our wave curve we have zones without any impact, while others have full force strength. Simulate to see the results and change the MultiBody's “Density” value if necessary.



Creating a Curve with a Force Limit

In this example, the force should be limited to 25% of its original strength. Another requirement is that this limit should be reached in the middle of the falloff area. Furthermore, the force should decrease quickly:

  • Delete the curve's current control points except the outermost left and right control points!
  • Do this with right-click > Remove control point.


Select the right control point and enter:

  • X > 0.5. This value represents the falloff area's midpoint.
  • Y > 0.25. The "Attractor" daemon's original strength is -200 and the minimum force is now -200 * 0.25 = -50.




The left control point's coordinates are

  • X = 0.0 and Y = 1.0 (100% of the original strength).
  • Drag the point's tangent (purple handle) downward to get a shape similar to the image above.
  • Simulate.