ADOBE AFTER EFFECTS 7.0
User Guide
339
• To resize the feature or search region, drag a corner handle.
• To make all of the region’s sides match the length of the longest side and to resize the region relative to the original
region’s center point, Shift-drag a corner handle.
• To make all of the region’s sides match the length of the longest side and to resize the region relative to a particular
corner handle, Shift+Ctrl-drag (Windows) or Shift+Command-drag (Mac (OS) the opposite corner handle.
See also
“To set a work area” on page 121
Restricting the movement of a motion target (Pro only)
Whenyoutrackmotioninalayer,AfterEffectscreatesamotionpathforyoutoapplytoamotiontarget,whichcan
be another layer, an effect, or the same layer. You can make the motion target follow only the x (horizontal) or y
(vertical) coordinates of the motion path, and you can also restrict the motion path to either plane. Restricting the
movement of a motion target can be useful in certain situations; for example, to make a speech bubble (the motion
target) remain at the top of the frame even when the actor’s head (the motion source) moves downward.
To restrict the movement of the motion target (Pro only)
1
Set up your track point.
2 Define the motion target, and then track the motion path. Adjust the tracking as needed until you’re satisfied with
the motion path.
3 To apply the motion path to the motion target, click Apply in the Tracker Controls panel, and choose one of the
following in the Motion Tracker Apply Options dialog box:
X Only Restricts the motion target to horizontal movement.
Y Only Restricts the motion target to vertical movement.
X And Y Enables the motion target to move across both the horizontal and vertical planes.
To bypass the Motion Tracker Apply Options dialog box and apply the last option you chose in it, hold down the Alt
(Windows) or Option (Mac OS) key when you click Apply in the Tracker Controls panel.
To restrict movement on a motion path (Pro only)
1
Do one of the following to set up your track point:
• To restrict the motion path to horizontal movement, resize the height of the search region to match the height of
the feature region.
• To restrict the motion path to vertical movement, resize the width of the search region to match the width of the
feature region.
2 Define the motion target, and then track the motion path.
To apply tracking data to a new target (Pro only)
Once you’ve tracked a motion source layer, you can apply that layer’s stored tracking data to other target layers. For
example, you can apply the track to a light bulb’s position and to the Lens Flare effect’s control point.
1 In the Tracker Controls panel, choose the tracked layer from the Motion Source menu.
2 Choose the track containing the tracking data you want from the Current Track menu.