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Freeform Animation B etween Footsteps 741
You can add freeform animation to footstep
animation during airborne periods, making
it possible to use both footstep and freeform
animationonthesamebiped.
Freeform animation is part icularly u sef ul for:
• Animating a charac ter with more than two legs.
• Animating a biped switching between
foot-based motion and freeform motion, such
as a biped doing handstands, jumping into a
sw imming po ol, or leaping up to beg in fly ing
through the air.
Freeform animation also provides animated
pivot points on the feet and hands. This makes it
possibleforyoutosimulatetherollofafootfrom
heel to toe, or create detailed finger animation.
You can convert back and forth between footstep
and freeform animation within 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
Working with Footstep Animation (page 2–714)
Working w ith Freeform Animation (page 2–743)
Freef orm A nima tion B et ween
Footsteps
For certain types of footstep animation, it is
necessary 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 will
become airborne during the swimming period,
jumping hig h in the air between the running 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 periods b etween
footsteps, see
Adjusting Vertical Motion (page
2–736)
.
To suspend g ravit y during an airborne period, you
can create a freeform period in your animation.
During a freefor m per io d, 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 Track View - Dope Sheet editor is used to
insert a freeform period between footsteps. During
a freeform period, vertical dynamics (gravitational
effects) are sus pended, and Body Vertical keys use
spline dynamics (page 3–1109) instead.
Procedure
To convert a n ai rbor ne per iod to fr eeform mode:
1.
Create a footstep animation with at least one
airborne period, and activate the footsteps.
For the simplest met hod of creating a footstep
patternwithanairborneperiod,see
Creating
Footsteps Automatically (page 2–720)
.
2. AccessTrackViewbychoosingGraphEditors
menu > Track View - Dope Sheet from the
3ds Max menu.
3. Expand the footstep key display for the biped.
4. Right-click the footstep key display a rea. The
Footstep Mode dialog appears.