9

Freeform Animation Between Footsteps 883
w ith 3ds Max, or other character animation
systems. Keys are set by using the character studio
Set Key tools found in the Key Info rollout (page
2–954), or by turning on Auto Key mode, moving
thetimesliderandtransformingthebipedparts.
Freeform animation includes preset key types
called planted, sliding, and f ree keys; these make
it very quick to lock a biped’s foot or hand in
space and get results similar to t hose of footstep
animation.
You can add freeform animation to footstep
animation during airborne periods, making
it possible to use both footstep and freeform
animationonthesamebiped.
Freeform animation is particularly useful for:
• Animating a character with more than two legs.
• Animating a biped sw itching between
foot-based motion and freeform motion, such
as a biped doing handstands, jumping into a
sw imming po ol, or leaping up to begin flying
through the air.
Freeform animation also provides animated
pivot points on the feet and hands. This ma kes it
possibleforyoutosimulatetherollofafootfrom
heel to toe, or create detailed finger animation.
You can convert back and forth between footstep
and f reeform animation w ithin some limitations.
While it is easy to convert any footstep animation
tofreeform,therearelimitationsontheconversion
from freeform animation to footsteps.
Because of these limitations, a common workflow
is to use footstep animation to rough out the
animation, then convert to freeform to finalize the
motions. The totally freeform animation is not
bound by the rules of the footstep method, so it’s
easy to do anyt hing you want, such as add keys at
the beginning or end of the clip.
See also
Footstep Animation (page 2–856)
Freeform Animation (page 2–886)
Freef or m A nim at ion Bet ween
Footsteps
For certain types of footstep animation, it is
necessar y to suspend calculations of gravitational
effects on the biped.
For example, if you want the biped to run, dive into
apoolthenclimboutofthepool,youwouldcreate
footsteps for the running and climbing portions
of the animation but not the swimming portion.
When you activate footsteps, the biped wil l
become airborne during the swimming period,
jumping hig h in the air b etween the r unning and
climbing footsteps.
If you don’t suspend gravity during the airborne
period,youwon’tbeabletochangethebiped’s
Body Vertical position to bring it down and place
it in the pool. For more information on how the
biped behaves during airborne per iods between
footsteps, see Adjusting Vertical Motion (page
2–878).
To suspend gravity during an airborne period, you
can create a freeform period in your animation.
During a freeform per iod, you can animate
the biped in freeform mode, which includes
positioning the biped anwhere in the scene
regardless of the length of the airborne period.
The Tr ack View - Dope Sheet editor is used to
insert a freeform period between footsteps. During
a freeform period, vertical dynamics (gravitational
effects) are suspended, and Body Vertical keys use
spline dynamics (page 3–1015) instead.