9

Layers Rollout 975
Honor in g I K Constr aint s A cross L ay ers
You can maintain a biped’s IK constraints ac ross
layers by retargeting its hands and feet to the
original layer. This assures that the biped’ s
constrained body par ts are honored and locked in
place while you make animation changes on the
upper la yers.
You can also choose to retarget a biped using
another one as reference. This is useful when you
need to precisely match hands and feet positioning
between two animated bipeds w ith different b o dy
proportions.
You can save an animation containing honored
constraintsacrosslayersinaBIP (page 3–916) file.
However, if the layered animation links to another
biped as reference, that link is not saved with the
animation.
Pr ocedur es
Example: To Maintain IK Constraints Across Layers:
This procedure takes in to accoun t the
fundamentals of animating across layers and
expands on the concept of honoring IK constraints.
1. Prepare a biped with IK keys on its feet, and its
left hand constrained to an IK object.
2. Select your biped and expand the L ayers rollout
on the Motion panel.
3. Create a new layer and rename it Low
center of mass.
The Retarget Left Ar m button in the Retargeting
group becomes active, which indicates that the
currentlayerhonorstheIKconstraintofthe
base layer for this body part.