Apple Motion 4 - Manual (Page 1267)

In the Canvas, a tracker appears at each corner of the foreground object. In the Inspector,
the default track list (Anchor and Rotation-Scale) is replaced with the Top Left, Top Right,
Bottom Right, and Bottom Left trackers.
5 If necessary, drag each tracker in the Canvas and fine-tune its position in the Tracker
Preview of the Inspector.
Important: To adjust the trackers without adjusting the foreground image, choose Mimic
Source from the Transform pop-up menu in the Behaviors tab of the Inspector. When
Attach to Source is chosen from the Transform pop-up menu, the foreground image is
distorted when the trackers are repositioned.
6 Click the Analyze button in the HUD or Behaviors tab of the Inspector.
The foreground element is “pinned” on the background element.
Note: If you adjust the Four Corner parameter for a layer, then apply a Match Move
behavior, the Four Corner parameter is automatically applied in the behavior. If you delete
the behavior, the four corner settings for the layer remain. If you reset the Match Move
behavior, the four corner settings are reset.
1267 Chapter 19 Motion Tracking