Adobe 12040118 - After Effects Standard, Руководство

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Bubble Orientation Determines the direction that the bubble rotates. Fixed releases the bubble from the producer right side up and keeps it that
way. Use this control if the bubble has built-in highlights and shading, as all of the preset bubbles do. Physical Orientation buffets and spins
bubbles around by the forces on them, creating a chaotic scene. Bubble Velocity faces the bubble in the direction of its motion. This setting is the
most useful for flocking-style animations.
Environment Map Specifies the layer that is reflected in the bubbles. If you want to use this layer only for the reflection, turn off the video switch
for a layer.
Reflection Strength Controls how much of the selected Environment Map is reflected in the bubbles. The higher the value, the more the reflection
obscures the original bubble texture. Reflections appear only on opaque pixels, so bubbles with high amounts of transparency, such as the Spit
preset, don’t reflect much.
Reflection Convergence Controls how much your Environment Map is distorted as it is mapped onto the bubbles. A value of 0 projects the map
flat on top of all of the bubbles in the scene. As the value increases, the reflection distorts to account for the spherical shape of each bubble.
Flow Map controls
The Flow Map controls specify the map that the flow of the foam follows:
Flow Map Specifies the layer used to control the direction and speed of the bubbles. Use a still image layer; if you select a movie as the flow map
layer, only the first frame is used. A flow map is a height map based on luminance: White is high, and black is low. White is not infinitely high; if a
bubble travels fast enough, it can travel past a white obstacle. Make sure that the map is a little blurry; sharp edges can create unpredictable
results. For example, to make bubbles flow through a canyon, create a flow map with a white canyon rim, a black canyon, and blurry gray walls.
Use wind to blow the bubbles in the direction you want them to flow, and the walls of the canyon contain them. You can also use a gentle gradient
on the floor of the canyon to control the flow direction.
Note: If the bubbles don’t follow the map, use the Simulation Quality control. Also, try blurring the flow map a little to make sure that it does not
have excessively abrupt edges.
Flow Map Steepness Controls the difference between white and black as they are used to determine steepness. If the bubbles are ricocheting
randomly off the flow map, decrease this value.
Flow Map Fits Specifies whether the flow map is relative to the layer or to the universe. The flow map resizes itself to fit whichever you specify.
This control is useful when you want to enlarge the universe but the flow map is designed for a particular layer, or when you want the bubbles to
start outside the frame and be affected by the flow map as they arrive in the frame.
Simulation Quality Increases the precision, and therefore the realism, of the simulation. However, the higher the value, the longer the
composition takes to render. Normal generally produces good results and takes the least amount of time to render. High returns better results but
takes longer to render. Intense increases the rendering time but produces more predictable bubble behavior. Use this option if the bubbles aren’t
following the flow map. It often solves problems of erratic behavior that can occur with small bubbles, high bubble speeds, and steep slopes.
Particle Playground effect
The Particle Playground effect lets you animate a large number of similar objects independently, such as a swarm of bees or a snow storm. Use
the Cannon to create a stream of particles from a specific point on the layer, or use the Grid to generate a plane of particles. The Layer Exploder
and Particle Exploder can create new particles from existing layers or particles. You can use any combination of particle generators on the same
layer.
David Van Brink provides a video walkthrough and downloadable example project on the omino website that show several things that you can do
with the Particle Playground effect, including how to use the Kinetic Friction ephemeral property mapper.
Brian Peterson provides a tutorial on the Videomaker website that shows how to use the Particle Playground effect to create a flock of birds.
This effect works with 8-bpc color.
Particles shooting out of the spacecraft layer (upper-left), text characters used as particles shooting out of a ray gun (lower-left), and Layer
Exploder used on spacecraft layer (lower-right)
Start by creating a stream or plane of particles, or by exploding an existing layer into particles. Once you have a layer of particles, you can control
their properties, such as speed, size, and color. You can replace the default dot particles with images from an existing layer to create, for example,