Match Move and Two-Point Tracking
If you use two-point tracking in a Match Move behavior, turn on (or off ) the Position,
Scale, or Rotation buttons (in the Adjust row of the Behaviors Inspector) to add or remove
tracking parameters, thereby achieving different effects.
In the following example, an oval shape (the foreground object) is match-moved to a
video clip of picture frames (the background object) using two-point tracking. In the first
three images below, only Position is enabled in the Adjust row of the Behaviors Inspector.
As a result, although the camera pushes in toward the picture frames, the white elliptical
shape does not change its scale or rotation based on the position of the two trackers.
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Chapter 22
Motion Tracking
In the next example, Position, Scale, and Rotation are enabled in the Adjust row of the
Behaviors Inspector. Consequently, the white elliptical shape changes its position, scale,
and rotation based on the position of the two trackers, matching the camera’s push
toward the picture frames and preserving the illusion that the shape is physically attached
to the picture frame.
Note: When using four-point tracking, scale and rotation are applied to the corner-pinned
object.