9
430 Chapter 12: Animation
Using a Dummy a s a Ha ndle
You might want to move and animate a selection
of objects i ndividually but also have the ability to
transformthemasasingleobject.
Agoodexampleofthisisacameraonatripod.
Youwanttoadjustboththecameraanditstarget
individually but also want to move them together
as a single unit.
Pr ocedur es
To crea te a complex bounce moti on u sing a du mmy
obj ect:
1.
Start with a sphere, then create a dummy object
below the sphere, and link the sphere as a child
of the dummy.
2. Animate the sphere bouncing up and down
above the dummy.
3. Animate the dummy moving.
The sphere bounces on top of the dummy
object as the dummy moves around the scene.
You can easi ly change the height and speed of
the bounce by changing the sphere animation.
You c an change the path through the scene by
changing the dummy animation.
To create a camer a t r ipod:
• Createadummyobjectbelowatargetcamera
and link the c a mer a and t arget as children of
the dummy object.
The camera and the target follow the dummy
object. You can quickly position the camera by
placing the dummy object and compose yo ur
view by adjusting the camera and its target.
Animating Links
You assign a Link constraint (page 2–403) to an
object to animate links from one parent to another.
You use a link constraint instead of using the
regular Select and Link and Unlink Selection
buttons on the toolbar. (See Animation Constraints
(page 2–392).)
An example of using a link constraint is to p ass
a ball from one hand to another. Assume that at
frame 0 the ball is in the first hand. The hands
are animated to meet at frame 50 and then spread
apart until fr ame 100.
To animate the link s for the ball:
1.
OntheMotionpanel,assignaLinkconstraint
as the ball’s Transform controller. You can
also put a Link constraint on the ball f rom the
Animation menu by choosing Constraints >
Link Constraint.
2. Move the time slider to frame 0, then on the
MotionpanelclickAddLink,andclickthe
hand holding the ba ll. T he ball will now move
alongwiththehand,asifitwerelinkedtoit.
3. Movethetimeslidertoframe50,whereyou
want the second hand to pick up the ball, click
Add Link, then click the second hand. From
this frame on, it’s as if the ball were linked to
the second hand.
When you play back the animation, the ball travels
withthefirsthanduntilframe50,whereyou
added the second link, then the bal l is passed to
thesecondhandfortherestoftheanimation.