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Understanding Biped 833
For information on these areas, consult the
remainder of this reference. If you don’t know
howtouse3dsMax,dosomeoftheintroductory
tutorials found online in Help > Tutorials.
Understanding Biped
Biped (page 2–843) is a 3ds Max component that
youaccessfromtheCreatepanel.Onceyoucreate
abiped,youanimateitusingtheBipedcontrolson
the Motion panel. Biped provides the tools you
need to design and animate the fig ures and motion
of characters.
The B iped
The biped skeleton created with the Biped module
is a two-legged figure created as a linked hierarchy,
anddesignedforanimation.Thebipedskeleton
has special propert ies that make it instantly ready
to anima te.
Figure a nd Keyf r ame Modes
character studio is designed to interchange
motion and characters. In Figur e mode (page
2–982), you pose the biped to fit your character
model. In Keyframe mode (page 3–960),you
animate the skeleto n. Motions created for the
bipedcanbesavedandloadedontootherbiped
skeletons with completely different physical
characteristics. For example, you could animate
a giant ogre, save the animation, and load it
onto a small child. Motion files are saved in the
proprietary character studio BIP format (page
3–916).
These fi les can be used in a variety of w ays with
Motion Flow, the Motion Mixer, or the Crowd
tools to combine animation or animate multiple
characters at once.
Animating the B iped
There are two primary methods used in creating
biped animation: footsteps method (page 3–943)
and freeform method (page 3–945).Eachmethod
has advantages. You can convert from one metho d
to the other , or you can use a combination of both
techniques in a single animation. For detailed
information, see the sections that follow: Creating
Footstep Animation (page 2–856) and Creating
Freeform Animation (page 2–886).
B iped P ropert ies
The biped skeleton has a number of propert ies
designed to help you animate faster and more
accurat el y.
• Ahumanstructure—Joints on the biped are
hinged to follow human anatomy. By default,
the biped resembles a human skeleton and has
a stable inverse kinematics hierarchy. This
means that when you move a hand or foot,
the corresponding elbow or knee orients itself
accordingly, and produces a na tural human
posture.
• Cus t omi zable for n on-human
str uctures—The biped skeleton can
easily be made to work with a four-legged
creature or an animal that naturally leans
for ward, such as a dinosaur.
• Natural rotations—When you rotate the biped
spine, the arms maintain t heir relative angle to
the ground, rather than behaving as if they were
fused to the shoulders. For example, say the
biped is in a standing position, arms hanging
at its sides; when you rotate the spine forward,
the biped’s fingers will touch the ground rather
than point behind it. This is a more natural
position for t he hands, and this speeds the
process of keyf r aming the biped. This feature
also applies to the biped head. When you
rotate the spine forward, the head maintains a
forward-looking orientation.