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734 Chapter 14: Character Studio
Restr ictions on B iped B ody K ey Editing
All options available for e diting biped body key
timing are available only when Edit Keys on the
Track View toolbar i s t urned on.
The following rules apply to the editing biped
body key timing in Track View:
• You cannot move existing keys outside the
area between the first a nd last footsteps, or to
negative frames.
• You c an use Add Keys to add keys to any biped
body track. You cannot add keys outside the
area between the first a nd last footsteps, or to
negative frames.
• Youcanclonekeysthesamewayyouclone
3ds Max object keys, by selecting keys and
holding down SHIFT as you drag them. You
can also clone keys by copying and pasting
postures. See
CopyingandPastingPostures
and Poses (page 2–768)
.
• The Track View – Cu rve Editor can be
used to view and edit curves showi ng the
interpolation b etween body keys. You can a lso
use the Workbench to analyze, edit and fix
biped motion curves. See
Working with the
Workbench (page 2–857)
.
• You can use Scale Keys to scale selected keys,
except for locked keys.
Tip: If you want to animate a biped performing
movements with its upper bo dy while standing,
extend the length of the standing footsteps to cover
the length of the standing animation, then add
keysfortheupperbody.
See also
Animating the Upper Body (page 2–732)
Shifting the B iped’ s Ba lance
After footsteps are activated, you can adjust the
biped’s overall balance in either of two ways:
•
In the Biped rollout (page 2–791) ,turn
on Rubber Band Mode and move the biped’s
COM, or
• Change or animate the B a lance Factor
parameter in the
Key Info rollout (p age 2–809) .
Rubber-Banding the COM
When Rubber Band mode is ac tive, you can move
the biped’s center of mass in relation to the rest
of the body, changing the biped’s overall balance.
Rubber-banding the center of mass defines your
character’s balance point in at-rest pose and in any
resulting motion.
When a character is standing at rest, with feet
side by side, the center of mass should be directly
above the area where the feet touch the ground.
The center of mass determines the center of your
character’s distribution of weight. For most
characters, the physical center of mass is located
near the pelvis.
Typicalplacementsforthecenterofmassare:
• Characters that st a nd erect, such as humanoids,
use the default location of the center of mass
within the pelvis.
• Characters that naturally lean forw ard, such
as some dinosaurs and birds, should have the
center of mass moved slightly forward of the
pelvis.Thisisalsogoodforrobotsanddroid
soldiers.
• Characters that are holding a heavy weight out
in front of them, or overweight characters,
might need their center of mass moved slig htly
forward of the pelvis.