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USING FLASH CS4 PROFESSIONAL
Timelines and Animation
Delete a motion path from a tween
1
Select the motion path on the Stage by clicking it with the Selection tool.
2
Press the Delete key.
Copy a motion path as a stroke
1
Click the motion path on the Stage to select it.
2
Choose Edit > Copy.
You can then paste the path into another layer as a stroke or as a motion path for another motion tween.
Apply a custom stroke as a motion path
You can apply a stroke from a separate layer or a separate timeline as the motion path for a tween.
1
Select a stroke on a layer separate from the tween layer and copy it to the clipboard.
The stroke must not be closed. Only uninterrupted strokes can be used.
2
Select a tween span in Timeline.
3
With the tween span still selected, paste the stroke.
Flash applies the stroke as the new motion path for the selected tween span. The target instance of the tween now
moves along the new stroke.
4
To reverse the start and end points of the tween, right-click (Windows) or Ctrl-click (Macintosh) the tween span
and select Motion Path
> Reverse Path in the tween span context menu.
Use roving property keyframes
A roving property keyframe is a keyframe that is not linked to a specific frame in the Timeline. Flash adjusts the
position of roving keyframes so that the speed of motion is consistent throughout a tween.
Roving keyframes are available only for the spatial properties X, Y, and Z. They are useful when you have edited a
motion path on the Stage by dragging the tweened object to different locations in different frames. Editing motion
paths this way often creates path segments in which the motion is faster or slower than the other segments. This is
because the number of frames in the path segment is greater or smaller than other segments.
Using roving property keyframes is helpful for making the speed of an animation consistent throughout a tween.
When property keyframes are set to roving, Flash adjusts the position of the property keyframes in the tween span so
that the tweened object moves the same distance in each frame of the tween. You can then use easing to adjust the
movement so that the acceleration at the beginning and end of the tween has a realistic appearance.
When you paste a custom path onto a tween, Flash sets the property keyframes to roving by default.
To enable roving keyframes for an entire tween:
•
Right-click (Windows) or Command-click (Macintosh) the tween span in the Timeline and choose Motion Path
>
Switch keyframes to roving in the context menu.
To enable roving for an individual property keyframe in a tween:
•
Right-click (Windows) or Command-click (Macintosh) the property keyframe in the Motion Editor panel and
choose roving in the context menu. For more information about the Motion Editor, see “
Editing property curves
with the Motion Editor
” on page 203.
When property keyframes are set to roving, they appear as round dots instead of squares in the Motion Editor.
Updated 5 March 2009
