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322 Chapter 12: Animation
7. Again scrub the animation, stop where you
want to set the upper limit, right-click the X
Position track, and choose Limit Controller >
Set Upper Limit.
In this example, we’ve set it at about 13. The
graph curve is now clipped above the upper
limit and below the lower limit. The resulting
motion is likewise constrained.
8. Scrub t he animation.
The motion on the X axis is limited at both
extremes; wherever the object originally moved
beyond the limits, it now behaves as though it’s
hitting a wall.
9. Again compare the two tracks.
The Limit Controller (X Posit ion) track clearly
showstheupperandlowerclipping,whilethe
Limited Controller track shows the original
motion.
The origin al motion still exists as the Limited
Cont roller track; you can restore it temporarily
by toggling the Limit controller.
10. Highlight the X Position track, and then
right-click and choose Limit Controller >
Toggle Limit.
Now, when you scrub the animation, the object
movesasbefore.
11. Choose Limit Controller > Toggle Limit again
to restore the limits
You can copy the Limit controller in two
ways: the lim its only, or the limits and motion
combined. First, you’ll copy the limits only.
12. Highlight the Y Posit ion track and note how its
curve differs from that of the X Position track.
13. Highlight the X Position track, and then
right-click and choose Limit Controller > Copy
Limit Only.
14. Highlight the Y Position track, and then
rig ht-click and choose Limit Controller > Paste
Limit Only. When the Paste dialog opens, click
OK to confirm the paste as a copy.
Now the Y Position track is also limited, using
the same extents as the X Position tr ack, but
retaining its original underlying motion. To
verify this, compare the Y Position track with
its child Limited Controller track.
Next, you’ll copy the entire limited X Position
track to the Z Position tr ack, including motion
and limits. The Z Position track cur rently is not
animated.
15. Highlight the X Position track, and then
right-click and choose Copy.
16. Highlight the Z Position track, and then
right-click and choose Paste.
Compare the X and Z Position tracks and both
their child Limited Controller tracks. Each
correspondingpairofcurvesisidentical.The