Adobe 12040118 - After Effects Standard, Руководство

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Note:
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Note:
Keyframe Rate
Note:
Keyframe Fields
Use Linear Vertex Paths
Bending Resistance
Quality
Add Mask Path Vertices
ascending order from the first vertex. After Effects then assigns the same numbers to the corresponding vertices at all successive keyframes. After
Effects interpolates the movement of each vertex from its initial position at one keyframe to the position of the correspondingly numbered vertex at
the next keyframe. At any time during an animation, you can designate another vertex as the first vertex; this causes After Effects to renumber the
vertices of the path. Renumbering vertices causes path animation to change, because After Effects then maps the new vertex numbers to the
corresponding old vertex numbers still saved at successive keyframes.
When copying a closed path into a motion path, the vertex designated as the first vertex of the closed path is used as the beginning of the motion
path. All motion paths are open paths.
Some shape path operations, such as Trim Paths, also use the first vertex as input to determine how to modify the path.
By default, when you add a vertex to a path, the new vertex appears on the path throughout the duration of the path but reshapes the path
only at the time at which it was added. When you delete a vertex from a path at a specific point in time, the vertex is deleted from the path
throughout the duration of the path. Prevent After Effects from adding and deleting vertices throughout the duration of the path by choosing Edit >
Preferences > General (Windows) or After Effects > Preferences > General (Mac OS), and deselecting Preserve Constant Vertex Count When
Editing Masks.
Note: Preserve Constant Vertex Count When Editing Masks is called "Preserve Constant Vertex and Feather Count when Editing Masks", in After
Effects CS6.
1. Create an animated path.
2. In the Timeline panel, move the current-time indicator to the point where you want to designate a new first vertex.
3. Select the vertex to designate as the first vertex.
4. Choose Layer > Mask And Shape Path > Set First Vertex.
The vertex designated as the first vertex appears slightly larger than the other vertices in the Composition panel.
Animate a mask path with Smart Mask Interpolation
Smart Mask Interpolation provides a high level of control for creating mask path keyframes and smooth, realistic animation. After you select the
mask path keyframes to interpolate, Smart Mask Interpolation creates intermediate keyframes based on settings you provide. The Info panel
displays the progress of the interpolation and the number of keyframes created.
1. Choose Window > Mask Interpolation.
2. Select at least two adjacent mask path keyframes.
3. Set options in the Mask Interpolation panel, and then click Apply.
To interrupt the interpolation process, press Esc. The Info panel indicates that the process has been interrupted and reports the
number of keyframes created.
Specifies the number of keyframes that Smart Mask Interpolation creates per second between the selected keyframes. For
example, a value of 10 creates a new keyframe every 1/10 of a second. Choose Auto to set the keyframe rate equal to the composition
frame rate, which appears in parentheses. Create more keyframes for smoother animation; create fewer keyframes to reduce render time.
Regardless of the keyframe rate you choose, Smart Mask Interpolation always adds keyframes at the frame just after the first mask
path keyframe and at the frame just before the second mask path keyframe. For example, if you interpolate between keyframes at 0 seconds
and 1 second in a 30-fps composition with a keyframe rate of 10 keyframes per second, mask path keyframes are added at frame numbers
1, 3, 6, 9, 12, 15, 18, 21, 24, 27, and 29.
Doubles the keyframe rate. When this option is selected, and Keyframe Rate is set to the composition frame rate, a
keyframe is added at each video field. Select this option for animated masking for interlaced video. If this option is not selected, the mask
may slip off the object that you are attempting to key out. For more information about fields in interlaced video, see
Interlaced video and
separating fields .
Specifies that vertices in the first keyframe move along a straight path to their corresponding vertices in the
second keyframe. Leave this option unselected if you want some vertices to interpolate along curved paths; for example, when the desired
interpolation involves rotating parts. If this option is not selected, Smart Mask Interpolation creates a natural path for the mask.
Specifies how susceptible the interpolated mask path is to bending instead of stretching. A value of 0 specifies that,
as the mask path animates, it bends more than it stretches; a value of 100 specifies that the mask path stretches more than it bends.
Specifies how strictly Smart Mask Interpolation matches vertices from one keyframe to another. A value of 0 specifies that a
particular vertex in the first keyframe matches only the same-numbered vertex in the second keyframe. For example, the tenth vertex in the
first keyframe must match the tenth vertex in the second keyframe. A value of 100 means that a vertex in the first keyframe can potentially
match any vertex in the second keyframe. Higher values usually yield better interpolations; however, the higher the value, the longer the
processing time.
Specifies that Smart Mask Interpolation adds vertices to facilitate quality interpolations. In general, Smart Mask