Animating Objects in Particle Systems
You can add behaviors to a particle system’s emitter, or to the cells themselves, to achieve
sophisticated, organic effects with very little effort. You can animate any emitter using
Basic Motion, Parameter, or Simulation behaviors. Emitter parameters and cell parameters
can also be animated via keyframes. If you animate emitter-specific parameters such as
Emission Angle or Emission Range, the position and distribution of new particles generated
by that emitter are animated. All animation occurs relative to the duration of the emitter.
Animating an emitter’s Properties Inspector parameters is useful for altering the position
and geometric distribution of a particle system over time. Keyframing an emitter’s Position
parameter moves the source of newly emitted particles without affecting any particles
generated at previous frames, creating a trail of particles.
Keyframing an emitter’s Emitter Inspector parameters is a good way to modify the particle
system’s overall characteristics over time, such as increasing or decreasing the size, speed,
or lifetime of newly generated particles.
Particles also have their own category of behaviors. The Particles behaviors include Scale
Over Life and Spin Over Life, which allow you to modify and animate the rotation and
size of the particles over their lifetime.
Using the Motion Tracking behaviors, you can apply existing tracking data to an emitter
or track an emitter to a clip. For more information on using the Motion Tracking behaviors,
see
Motion Tracking
.
714
Chapter 14
Working with Particles
For an example of a keyframed emitter object in a particle system, see
Example 2: Creating
Animated Pixie Dust
. For more information on keyframing parameters in the Keyframe
Editor, see
Keyframes and Curves
.