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Adobe After Effects Help Creating Particle Effects (PB only)
Using Help | Contents | Index Back 354
Improving performance with Particle Playground (PB only)
You can animate a large number of similar objects so that they move independently but
produce a consistent group behavior overall, such as animating falling snow, swarming
bees, or exploding fireworks. The following guidelines can help you work more efficiently:
• When you’re generating a Particle Playground effect, keep an eye on the Info palette to
see how many particles are being produced. If an effect contains more than 10,000
particles, it can significantly slow rendering.
• The Grid and Layer Exploder generate particles on every frame, which may generate too
many particles for the effect you’re creating and slow down rendering. To avoid
continuous particle generation, animate these options to decline to zero over time:
Layer Exploder, Radius of New Particles, Grid Radius, Particle Radius, and Font Size. Then
the Particle Playground generates new particles only at the start of a sequence.
The grid generates particles for every frame by default.
In this example, a keyframe for the point size of the grid particles was set to zero on the second
frame, so only particles generated on the first frame appear.
• When you apply a Particle Playground effect to a layer, the particle positions aren’t
limited to the bounds of that layer. To control particles that you can't see or that appear
near the edge of the image, use a Selection or Property Map that’s larger than the area
of the Particle Playground layer. Also, note that After Effects takes an image map’s alpha
channel into account. If you want transparent areas of your map to affect the particles,
precompose the map layer with a black solid behind it.
To specify field-rendering with a Particle Playground effect, select Enable Field Rendering
in the Particle Playground Options dialog box. Then Particle Playground calculates the
simulation at double the frame rate of the current composition, which is what field
rendering requires.
Creating particles (PB only)
Create particles using the Cannon, the Grid, the Layer Exploder, and the Particle Exploder.
The Cannon is on by default and must first be turned off before using a different method
to create particles. It creates particles in a continuous stream, as though they were shot
out of a cannon. The Grid creates particles in an organized grid format with straight rows
and columns. The exploders create particles randomly, like firecracker sparks.
Particle Playground Cannon (PB only)
By default, the Cannon shoots red particles toward the top of the frame at 100 particles
per second.