Adobe 12040118 - After Effects Standard, Руководство

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Aharon Rabinowitz provides a video tutorial on his All Bets Are Off website that shows how to use the Skew properties of the Transform effect to
simulate perspective in the movement of a cloud layer based on a still image.
Turbulent Displace effect
The Turbulent Displace effect uses fractal noise to create turbulent distortions in an image. For example, use it to create flowing water, funhouse
mirrors, and waving flags.
Rhys Enniks provides a demonstration of the Turbulent Displace effect in part 2 of his “Rain over water” tutorial on his website .
This effect works with 8-bpc, 16-bpc, and 32-bpc color.
Displacement The type of turbulence used. Turbulent Smoother, Bulge Smoother, and Twist Smoother each perform the same operations as
Turbulent, Bulge, and Twist, except that the Smoother options create smoother warps and take longer to render. Vertical Displacement warps the
image vertically only. Horizontal Displacement warps the image horizontally only. Cross Displacement warps the image both vertically and
horizontally.
Amount Higher values cause more distortion.
Size Higher values cause larger areas of distortion.
Offset (Turbulence) Determines the portion of the fractal shape that is used to create the distortion.
Complexity Determines the level of detail in the turbulence. Lower values cause smoother distortions.
Evolution Animating this setting results in changes of the turbulence over time.
Note: Although the Evolution value is set in units called revolutions, it’s important to realize that these revolutions are progressive. The Evolution
state continues to progress infinitely at each new value. Use the Cycle Evolution option to return the Evolution setting to its original state at each
revolution.
Evolution Options Evolution Options provide controls that render the effect for one short cycle and then loop it for the duration of the layer. Use
these controls to pre-render turbulence elements into loops, and thus speed up rendering time.
Cycle Evolution Creates a loop that forces the Evolution state to return to its starting point.
Cycle The number of revolutions of the Evolution setting that the fractal cycles through before it repeats. The amount of time between
Evolution keyframes determines the timing of the Evolution cycles.
Note: The Cycle control affects only the state of the fractal, not geometrics or other controls, so you can get different results with different
Size or Offset settings.
Random Seed Specifies a value from which to generate the fractal noise. Animating this property results in flashing from one set of fractal
shapes to another (within the same fractal type), which is not usually the result that you want. For smooth transition of the fractal noise,
animate the Evolution property.
Note: Create new turbulence animations by reusing previously created Evolution cycles and changing only the Random Seed value.
Using a new Random Seed value alters the noise pattern without disturbing the Evolution animation.
Pinning Specifies which edges to pin so that the pixels along those edges aren’t displaced.
Resize Layer Enables the distorted image to expand past the original bounds of the layer.
Create a seamless loop using Turbulent Displace
1. Set two keyframes for the Evolution control, using full revolutions only.
2. Adjust the time between keyframes, and the number of Evolution revolutions until you’re satisfied with the appearance of the displacement.
3. Select Cycle Evolution.
4. Set a value for Cycle that’s evenly divisible by the number of revolutions that you set for Evolution.
5. In the Timeline panel, move the current-time indicator to the time where the cycle completes. For example, if the Cycle value is 2, find the
frame where the Evolution value is 2 revolutions.
6. Move the current-time indicator back one frame, to prevent a duplicate frame in the seamless loop.
7. Press the right bracket key (]) to trim the layer Out point to the current time.
8. Pre-render this layer, and import it into the project.
9. Set this prerendered footage item to loop. (See Loop a footage item.)
Note: If you set keyframes for any of the other controls, you must return them to their initial settings at the point on the Timeline panel
where the cycle begins to repeat. Otherwise, these properties don’t loop.
Twirl effect
The Twirl effect distorts an image by rotating a layer around its center. The image is distorted more sharply in its center than at the edges, causing
a whirlpool result at extreme settings. Because distortion in this effect is significant, After Effects uses special anti-aliasing techniques to produce
the highest-quality image. As a result, the Twirl effect can be especially slow to render.
This effect works with 8-bpc, 16-bpc, and 32-bpc color.
Angle How far to twirl the image. Positive angles twirl the image clockwise; negative angles twirl it counterclockwise. For a whirlpool result,
animate the angle.