Apple Motion 5.1.1 - Manual (Page 514)

Chapter 14 Particles 514
Think of the particle cell as the “mold” for the particles generated in the Canvas by the emitter.
You can use nearly any layer or group in Motion as a source for a particle cell, including images,
shapes, text, movies, and image sequences. Each particle created in the Canvas is essentially a
duplicate of the cell, and is animated according to the parameters of that particle system over
its lifetime.
Object prior to becoming a particle system Particle system
The layer you use as a particle system’s cell determines the appearance of that particle system.
Particle systems can contain multiple cells, resulting in the release of several types of particles
from a single emitter. Many of the most sophisticated particle presets in the Particle Emitters
library are constructed in this way.
Particle system based on a single cell Particle system based on two cells
Each element in a particle system appears in the Layers list and Timeline. In addition to the
emitter and its cells, the original images or shapes used to create the cells (the cell source objects)
appear in the Layers list, disabled so that they do not appear in the Canvas. Each cell appears as a
sublayer underneath the emitter (click the disclosure triangle beside the emitter layer to hide or
reveal its sublayers).
Cell (with behaviors applied)
Original object (disabled)
Emitter
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