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Using Help | Contents
Use Repel to avoid collisions between particles. Repel is useful for pushing particles
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apart, such as after applying the Layer Exploder. Use Repel to cause particles to attract
by typing a negative value.
Use Wall to contain particles within an area. Wall is useful for ping-pong effects.
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Particle behavior works in conjunction with other Particle Playground properties. For
example, if you set a Cannon particle velocity that fires particles across the frame and out
the opposite side, you can increase the Gravity Strength until it pulls those particles down
before they exit the frame.
Influencing individual particles over their lifespan (PB
only)
To have full control over particle movement and appearance, you must balance the
properties you assign to particles at particle birth (Cannon, Grid, Layer Exploder, and
Particle Exploder) with the properties you assign to the particle's lifespan (Gravity, Repel,
Wall, and Property Mapper). For example, if you want to use the Cannon to shoot sparks
that fade over time, it may seem that you need only animate the Cannon's Color option.
However, using this method, you change only the color of each new particle as it's created.
To control the color for the lifespan of particles, you must create a layer map and use the
Property Mapper to alter the particles' color channels.
The following list covers common particle behavior. For more information on these items,
see "About Property Mappers (PB only)" on page 366.
Speed At particle creation, particle velocity is set by the Cannon and the exploders; Grid
particles have no initial speed. After particle creation, use the Force option in the Gravity
and Repel properties. You can also influence the speed of individual particles by using a
layer map to set values for the Speed, Kinetic Friction, Force, and Mass properties in the
Property Mappers.
Direction At particle creation, the Cannon includes particle direction, the Layer Exploder
and Particle Exploder send new particles in all directions, and Grid particles have no initial
direction. After particle creation, direction can be influenced by the Direction option in
the Gravity property, or by using a mask with the Wall property. You can also influence the
direction of individual particles by using a layer map to set values for the Gradient Force, X
Speed, and Y Speed properties in the Property Mappers.
Area Use a Wall mask to contain particles to a different area or to remove all barriers. You
can also restrict particles to an area by using a layer map to set values for the Gradient
Force property in the Property Mappers.
Appearance At particle creation, the Cannon, Grid, Layer Exploder, and Particle Exploder
operators set particle size unless you replace the default dots with a layer map. The
Cannon and Grid set the initial color, while the Layer Exploder and Particle Exploder take
color from the exploded dot, layer, or character. The Options dialog box affects the initial
appearance of text. After particle creation, you can use the Property Mappers to set values
for the Red, Green, Blue, Scale, Opacity, and Font Size properties.
Using Help | Contents
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Creating Particle Effects (PB only)
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