There
are two ways to make tubes react to forces:
- define Paint Effects brush
forces
- apply forces to stroke control curves
Use brush settings to make
tubes react to forces
You can make strokes
react to forces such as gravity, deflection, and momentum by applying
the settings under Tubes > Behavior > Forces.
For details, see
Set force attributes.
Keyframe these settings to make the tubes move dynamically in reaction
to the forces.
You can also add turbulence
to brushes. Simply turn turbulence on for a stroke, and Paint
Effects automatically animates the reaction of the tubes.
To apply turbulence to brushes
- Select the stroke.
- In the Attribute Editor,
expand Tubes > Behavior > Turbulence.
- Change the Turbulence Type from
off to any of the other options, then define the turbulence settings
you want applied to the stroke tubes. For details, see
Set turbulence attributes.
- In the scene view, click the Play
Forward button to check that the effect is as you want
it. You can tweak the turbulence settings while playing.
Use control curves to make
tubes react to forces
If
you want stroke tubes to react to forces other than the forces available
in the Paint Effects brushes (or in
addition to), you can do so by creating control curves and making
the control curves react to the forces in your scene. This is an
effective technique, for example, for making long hair move naturally or
for adding localized forces to trees.
To animate tube behavior by applying
forces to control curves
- Create the control curves. For details,
see
Modify tube behavior using control curves.
- Select the stroke(s) you want controlled
by the control curves and set the Curve Follow and/or Curve
Attract to values for the stroke(s) to be other than
0.
- Make the control curves into soft bodies
as follows:
- Add the desired force fields to the scene
(for example, select
Fields > Vortex)
and position them to affect the control curves.
- In the scene view, click the Play
Forward button to check that the effect is as you want
it.
- Render the animation. See
Create a composite of Paint Effects strokes and your scene.