Adobe 12040118 - After Effects Standard, Руководство

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Gravity, Repel, Wall, and Property Mapper settings. By default, the Force control of Gravity is on, so Grid particles fall toward the bottom of the
frame.
With the Grid, a new particle appears on every frame at each grid intersection. You can’t adjust this frequency, but if you want to turn off the Grid
or make the Grid stop generating particles at specific times, set the Particle Radius/Font Size control to 0, or use keyframes to animate the value
of the Particles Across and Particles Down controls. To make more particles appear in each frame, increase the values for Particles Across and
Particles Down.
Note: By default, the Cannon is on and the Grid is off. If you are using the Grid and want to stop the Cannon from generating particles, turn off
the Cannon by setting its Particles Per Second value to 0.
Position
Specifies the (x,y) coordinates of the grid center. When a grid particle is created, it is centered over its grid intersection, regardless of
whether it is a dot, a layer, or a text character. If you’re using text characters as particles, the Use Grid option in the Edit Grid Text dialog box is on
by default, placing each character on its own grid intersection, so normal character spacing, word spacing, and kerning do not apply. If you want
text characters to appear at the grid position with normal spacing, use a text alignment other than the Use Grid option.
Width, Height Specify the dimensions of the grid, in pixels.
Particles Across, Particles Down Specify the number of particles to distribute horizontally and vertically across the grid area. Particles are
generated only when the value is 1 or more.
Note: If the Width, Height, Particles Across, and Particles Down controls are not available, the Use Grid option has been turned off in the Edit
Grid Text dialog box.
Color Sets the color of dots or text characters. This control has no effect if you use a layer as the particle source.
Particle Radius/Font Size Sets the radius of dots in pixels or the size of text characters in points. This control has no effect if you use a layer as
the particle source.
Layer Exploder and Particle Exploder
The Layer Exploder explodes a layer into new particles, and the Particle Exploder explodes a particle into more new particles. In addition to
explosion effects, the exploders are also handy for simulating fireworks or for rapidly increasing the number of particles.
The following guidelines can help you control particles resulting from an explosion:
A layer is exploded once for each frame. By default, this creates a continuous shower of particles for the duration of the composition. If you
want to start or stop a layer explosion, animate the Radius of New Particles control by using keyframes so that its value is zero at times
when you don’t want particles to be created.
If the source of the layer is a nested composition, you can set different Opacity values or In and Out points for the layers within the nested
composition to make the exploding layer transparent at different points in time. The Layer Exploder does not create particles where the
source of the layer is transparent.
To change the position of the exploding layer, precompose the layer with its new position (use the Move All Attributes Into The New
Composition option), and then use the precomposed layer as the exploding layer.
When you explode particles, the new particles inherit the position, velocity, opacity, scale, and rotation of the original particles.
After layers or particles explode, Gravity, Repel, Wall, and Property Mapper controls influence the movement of particles.
Some Persistent Property Mapper and Ephemeral Property Mapper options can make explosions more realistic. For example, change
Opacity to make the resulting particles fade out, or change the Red, Green, and Blue color channels to make resulting particles change
color as they appear to cool.
Explode Layer (Layer Exploder only) Specifies the layer you want to explode. To make the video disappear the moment the particles appear,
either turn off the video for the layer or trim the Out point of the layer.
Radius Of New Particles Specifies the radius of the particles resulting from the explosion. This value must be smaller than the radius of the
original layer or particle.
Velocity Dispersion Specifies, in pixels per second, the maximum speed of the range within which Particle Playground varies the velocity of the
resulting particles. High values create a more dispersed or cloudlike explosion. Low values keep the new particles closer together and can make
the exploded particles resemble a halo or shockwave.
Affects Specifies which particles the Layer Exploder and Particle Exploder affect.
Layer Map controls
By default, the Cannon, Grid, Layer Exploder, and Particle Exploder create dot particles. To replace the dots with a layer in the composition, use
the Layer Map. For example, if you use a movie of a single bird flapping its wings as a particle source layer, After Effects replaces all dots with an
instance of the bird movie, creating a flock of birds. A particle source layer can be a still image, a solid, or a nested After Effects composition.
A multiframe layer is any layer with a source that varies over time, such as a movie or a composition. When you map new particles to a multiframe
layer, use the Time Offset Type control to specify how you want to use the frames of the layer. For example, use Absolute to map an unchanging
image onto a particle, or use Relative to map an animating sequence of frames onto a particle. You can randomize both Absolute and Relative
across particles.
Note: When you choose a layer for Layer Map, Particle Playground ignores any changes that you made to that layer within that composition.
Instead, it uses the layer in its original state. To keep transformations, effects, masks, rasterization options, expressions, or keyframe changes for
a layer when you use it as a particle source, precompose the layer.
Use Layer
Specifies the layer you want to use as the particles.