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404 Chapter 12: Animation
An example of using a link constraint is to p ass
a ball from one hand to another . Assume that at
frame 0 the bal l is in the rig ht hand. The hands
are animated to meet at frame 50, where the ball is
passed to the left hand, and then spread apart until
frame 100.
Pr ocedur es
Example: To assign a Link constraint:
1.
IntheTopviewport,createasphereandabox.
2. Select the sphere.
3. Open the Motion panel.
4. Expand > Assign Controller rollout.
5. Select the Transform: Position/Rotation/Scale
controller.
6. Click Assign Controller.
7. Choose Link Constraint.
ItisrecommendedthatyouaddaLinkTo
World b efore lin k ing to any target objects. This
w i ll allow you to animate the object on its own,
before the first link to a target object takes place.
You can also assign Link Constraints through
the Animation > Constraints submenu.
To access the Link constraint’s parameters through
the Motion panel:
1.
Select the Link-constrained object.
2. Choose Motion panel > Link Params rollout.
Example: To a ssign the Link constraint and animate
links:
1.
Move the time slider to frame 0.
2. In the Top viewport, create a sphere, a cylinder
and a b ox.
3. Select the sphere.
4. Open the Motion panel.
5. Expand the Assign Controller rollout.
6. Select the Transform: Position/Rotat ion/Scale
controller.
7. Click Assign Controller.
8. Choose Link Constraint.
9. In the Link Params rollout, click Link To World.
10. Movethetimeslidertoframe1.
11. Click Add Link and select the cylinder.
It now becomes a target. The Link C onstraint
relationship is now active between the sphere
and the cylinder.
12. Movethetimeslidertoframe50.
13. Turn on the Auto Key button and move the
cylinder a good distance away from where it is.
14. Play back the animation.
Thespherefollowsthecylinderasitmoves.
Thesphereislink-constrained.
15. Select the sphere.
16. Movethetimeslidertoframe25.
17. On the Motion panel > Link Param rollout,
click Add link and select the box.
You have now adde d another target that
becomes a ctive at frame 25.
18. Turn off the Auto Key button and play back the
animation. The sphere is linked to the cylinder
from frame 0 to 24. It follows the cylinder until
frame 25 where it link s to the box.