9

Exporting Animation to the Biped 625
• If transitions between different foot/leg
motionshavecreatedsmallpopsorjerksnear
the transition area, you will want to create
a mixdown (page 3–973) for the biped and
check the mixdown befor e copying it to the
biped. A mixdown can correct many continuity
problems with feet and legs. You can correct
transitions and recompute the mixdown as
many times as you like. When the mixdown is
satisfactory, you can copy it to the biped.
If you want to use the motion with a different
biped, you can copy the mixdown to the current
biped, save the motion as a BIP file, and load the
new BIP file onto the other biped.
ThemixcanalsobesavedasaMIX(.mix)file.A
MIX file (page 3–973) can be loaded onto other
bipeds and edited as needed in the Motion Mixer.
Fixi ng Foot-Ba sed Tra nsi tions with a
Mixdown
When you create a transition between two motions
w ith plante d feet (feet with IK constraints), the
motion mig ht not match perfectly between clips.
When this occurs, a planted foot might slide or
pop, or a leg might stretch unnaturally during or
near the transition period.
A mixdown can correct two types of problems
during transitions between foot-based motions:
• A foot sliding as it transitions from one planted
motion to another.
• A leg extending completely straight
(hy per-extending) unnaturally to reach a
planted position.
The m ixdown options on the Mixer
Preferences dialog (page 2–651) can help correct
these problems. To access this dialog, click
Preferences on the Motion Mixer toolbar.
Tohaveaneffectonamixdown,theseoptions
must be set b efore the mixdown is computed. If
Prompt for options at each Mixdown is turned
on, you will be prompted to set these options
each time you compute a mixdown. Otherwise,
the mixdown uses the settings on the Mixer
Preferences dialog.
TheoptionsintheMixdownOptionsgroup
determine if and how the mixdown affects
transitions b etween clips with planted feet.
Enforce IK Constraints affects planted feet, while
Filter Hyper-Extended Legs affects unnaturally
straig ht legs. Turn on Prompt for options at
each Mixdown if you wan t to be asked for these
settings each time you do a mixdown. For
more information on these options, see Mixer
Preferences Dialog (page 2–651).
Tip: You should not rely on the mixdown process
to correct extreme problems with clips or
transitions. For the best results, adjust transitions
before a mixdown to minimize sliding feet and
hyper-extending legs. See Working with Transitions
(page 2–616).
Procedures
To perform a mixdown and copy it to the biped:
1.
SelectthebipedintheMotionMixerby
clicking the biped name at the upper left of the
trackgroup set.