Apple Motion 5.1.1 User Manual
Page 549
Chapter 14
Particles
549
Spin Over Life parameters
The Spin Over Life behavior has one main parameter control and three optional parameter
controls that vary, depending on the selected Increment Type:
•
Increment Type: A pop-up menu that determines which method is used to spin particles over
their lifetime. There are three options:
•
Rate: Specifies a steady rate and direction in which particles spin over their lifetime. When
Rate is selected, the Spin Rate parameter becomes available.
•
Birth and Death Values: Specifies starting and ending spin degrees used to animate each
particle’s rotation over its lifetime. The spin amount generated by this option for a specific
particle at a specific time is added to the pre-existing particle spin (defined in the Cell
Controls section of the Emitter Inspector). When this option is selected, the Spin At Birth and
Spin At Death parameters become available.
•
Custom: When Increment Type is set to Custom, a mini-curve editor appears that lets you
customize the spin of the particles over their lifetime. Click the disclosure triangle to display
the mini-curve editor in the Inspector. For more information on using mini-curve editors, see
on page 482.
•
Spin Rate: Defines how quickly each particle spins and the direction of the spin. Positive
values spin particles faster over time and in a counterclockwise direction; negative values spin
particles slower over time and in a clockwise direction.
•
Spin At Birth: Determines the initial spin of the particles when they are created.
•
Spin At Death: Determines the spin of the particles at the end of their lifetime.
•
Custom Spin group: This group of parameters (a mini-curve editor and several other controls,
described below) appears when Increment Type is set to Custom. Use the mini-curve editor for
more precise control over the Spin of particles in your particle system.
•
Custom Spin: Use this dial to adjust the value of the selected keyframe in the mini-
curve editor. This parameter appears when Custom is selected in the Increment Type
pop-up menu.
•
Over Life: Use this slider to adjust the position of the selected keyframe in the life of
the particle. This parameter appears when Custom is selected in the Increment Type
pop-up menu.
The HUD contains the Increment Type pop-up menu, and the Spin Rate, Spin At Birth, and Spin
At Death parameters.
Note: When you animate an emitter or cell parameter using keyframes, a curve describing that
animation appears in the Keyframe Editor. The selected object determines which curves appear
in the Keyframe Editor (when Animated is selected from the pop-up menu in the top-left corner
of the Keyframe Editor).
View animated emitter curves in the Keyframe Editor
When you animate an emitter or cell parameter using keyframes, a curve describing that
animation appears in the Keyframe Editor. The selected object determines which curves appear
in the Keyframe Editor (when Animated is selected from the pop-up menu in the top-left corner
of the Keyframe Editor).
Display animated emitter or cell curves
m
Select the emitter to display animated emitter parameters such as Position and Rotation (in the
Properties Inspector) or Emission Angle and Range (in the Emitter Inspector).
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