GrowFX 2.0 User Manual

Spline direction node

This modifier is used to specify the direction of the pathlines along the spline.

Spline object group

Pick spline

Click this, and then select a spline in the viewport.

Extract spline

Lets you create a new spline in the scene as an instance for further modification.


Displays the name of the spline object.


Orientation angle of a spline along the direction of a start vector.

Chaos angle

Chaos of orientation angle.


Sets a spline scale.

Chaos scale %

Chaos scale in percent.

Length < Spline length

When on, the length of a created pathline will be no more than the length of a spline.

Randomize sample spline

If a spline object consists of several splines, this option allows use splines at random during generating multiple pathlines.

Interpolation between splines group


Enables smooth interpolation between several splines.

Interpolation value

Specifies the interpolation value, range 0.0 to 1.0. If value is 0.0, the first spline in a spline object is used. If is 1.0, the last spline is used. Hence, the value in the range from 0.0 to 1.0 will be provided by a spline as a result of interpolation from the first to the last spline in a spline object.

An example:

An example of using interpolation between several splines:

An example above shows a spline object that consists of three splines.

To create a similar spline object, follow these steps:

  • Create 3 splines as a single spline object. If possible, create similar number of vertices;
  • Add the Spline direction modifier for branches and select this spline using Pick Spline;
  • Enable interpolation by checking Interpolation;
  • Set the Interpolation value = 1.0;
  • Affects to this parameter from the position of branches on the trunk, i.e. in Path distributor node for branches create a new Affect node from Parameter: Path position, and connect the Affect Out connector to the Interpolation value;
  • Create the Curve node for the Factor, and set an upward curve from 0.0 to 1.0. As a result, values of Interpolation value will be multiplied by the value of this curve and give a change from 0.0 to 1.0 along the length of the trunk, starting from bottom branches all the way to the top ones. For a bottom branch the value of Interpolation value will be equal to 0.0 and for the top branch - 1.0. Consequently, the first spline will be used at the bottom and the third will be used on top;
  • If necessary, enable the Length < Spline length to make the length of branches the same as splines.