Apple Motion 2 - Manual (Page 581)

Chapter 8 Working With Particles 581
Transform Controls
As a particle system plays, the cells in the system are duplicated, according to the
parameters for that system, to create each individual particle. Since all particles emerge
relative to the position of the emitter (since the emitter can be a point, a circle,
geometry, and so on), changing the emitter’s position in the Canvas also changes the
position of every particle in that system. This results in the entire particle system being
moved at once.
The exception to this is if the emitter’s position is animated using a behavior or
keyframes. In this case, particles emerging from the emitter’s position at each frame
continue to move relative to that position, regardless of changes to the emitter’s
position in subsequent frames. This results in a trail of particles following the path of
the emitter.
The Attach to Emitter particle cell parameter modifies this behavior. When set to 0
percent, the particles are completely independent of the emitter. When set to 100
percent, the particles try to keep up with the position of the animated emitter.
Depending on any applied behaviors, such as Drag, the particles may not be able to
keep up with the emitter.
Origin of particle system Origin of particle system
01112.book Page 581 Sunday, March 13, 2005 10:36 PM