Adobe 12040118 - After Effects Standard, Руководство

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either side of the keyframe. Unlike Auto Bezier or Continuous Bezier, the two direction handles on a Bezier keyframe operate independently in both
the value graph and motion path.
If you apply Bezier interpolation to all keyframes of a layer property, After Effects creates a smooth transition between keyframes. The initial
position of the direction handles is calculated using the same method used in Auto Bezier interpolation. After Effects maintains existing direction
handle positions as you change a Bezier keyframe value.
Unlike other interpolation methods, Bezier interpolation lets you create any combination of curves and straight lines along the motion path.
Because the two Bezier direction handles operate independently, a curving motion path can suddenly turn into a sharp corner at a Bezier
keyframe. Bezier spatial interpolation is ideal for drawing a motion path that follows a complex shape, such as a map route or the outline of a logo.
Existing direction handle positions persist as you move a motion-path keyframe. The temporal interpolation applied at each keyframe controls the
speed of motion along the path.
Auto Bezier interpolation
Auto Bezier interpolation creates a smooth rate of change through a keyframe. You may use Auto Bezier spatial interpolation to create the path of
a car turning on a curving road.
As you change an Auto Bezier keyframe value, the positions of Auto Bezier direction handles change automatically to maintain a smooth
transition between keyframes. The automatic adjustments change the shape of the value graph or motion path segments on either side of the
keyframe. If the previous and next keyframes also use Auto Bezier interpolation, the shape of the segments on the far side of the previous or next
keyframes also changes. If you adjust an Auto Bezier direction handle manually, you convert it to a Continuous Bezier keyframe .
Auto Bezier is the default spatial interpolation.
Continuous Bezier interpolation
Like Auto Bezier interpolation, Continuous Bezier interpolation creates a smooth rate of change through a keyframe. However, you set the
positions of Continuous Bezier direction handles manually. Adjustments you make change the shape of the value graph or motion path segments
on either side of the keyframe.
If you apply Continuous Bezier interpolation to all keyframes of a property, After Effects adjusts the values at each keyframe to create smooth
transitions. After Effects maintains these smooth transitions as you move a Continuous Bezier keyframe on either the motion path or the value
graph.
Hold interpolation
Hold interpolation is available only as a temporal interpolation method. Use it to change the value of a layer property over time, but without a
gradual transition. This method is useful for strobe effects, or when you want layers to appear or disappear suddenly.
If you apply Hold temporal interpolation to all keyframes of a layer property, the value of the first keyframe holds steady until the next keyframe,
when the values change immediately. In the value graph, the graph segment following a Hold keyframe appears as a horizontal straight line.
Even though Hold interpolation is available only as a temporal interpolation method, the keyframes on the motion path are visible, but they are not
connected by layer-position dots. For example, if you animate the Position property of a layer using Hold interpolation, the layer holds at the
position value of the previous keyframe until the current-time indicator reaches the next keyframe, at which point the layer disappears from the old
position and appears at the new position.
You can easily freeze the current frame for the duration of the layer using the Freeze Frame command. To freeze a frame, position the current
time indicator at the frame you want to freeze. Make sure that the layer is selected and then choose Layer > Time > Freeze Frame. Time-
remapping is enabled, and a Hold keyframe is placed at the position of the current time indicator to freeze the frame.
Note: If you previously enabled time-remapping on the layer, any keyframes you created are deleted when you apply the Freeze Frame
command.
You can use Hold interpolation only for outgoing temporal interpolation (for the frames following a keyframe). If you create a keyframe following a
Hold keyframe, the new keyframe uses incoming Hold interpolation.
To apply or remove Hold interpolation as outgoing interpolation for a keyframe, select the keyframe in the Timeline panel, and choose
Animation > Toggle Hold Keyframe.
Apply and change keyframe interpolation methods
You can apply and change the interpolation method for any keyframe. You can apply changes using the Keyframe Interpolation dialog box, or you
can apply them directly to a keyframe in layer bar mode, in a motion path, or in the Graph Editor. You can also change the default interpolation
After Effects uses for spatial properties.
For information on using Easy Ease controls to automatically ease speed between keyframes, see Controlling speed between keyframes.
Change interpolation method with the Keyframe Interpolation dialog box
The Keyframe Interpolation dialog box provides options for setting temporal and spatial interpolation and—for spatial properties only—roving
settings.
1. In layer bar mode or in the Graph Editor, select the keyframes you want to change.