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1004 Chapter 14: character studio
Because of Biped Dynamics, no keys are necessary for the
highest part of this ju mping m otion or for the dip when the
biped lands; character studio calculates the trajectory of
the Body. This image shows the center of m ass trajectory.
Keyframesarewhitesquaresonthetrajectory.
Simply change gravity (GravAccel on the D ynamics &
Adaptation rollout), and the jumping motion is flattened. The
biped looks like it ’s hopping on the moon.
By selecting half the footsteps in Track View - Dope Sheet and
moving them to the right in time, the biped has to jump higher
to account for the added time to the next footstep. N otice
that the yellow dots, representing frames, are tightly bunched
together; there are more frames in this airborne period.
Here, the center of mass is moved in the Z plane. Now the b iped
heel never hits the ground; the biped appears to do a jum p
using just its toes. Here, character stu dio understands that
you want to override the calculated trajectory and position
the keyframe yourself.
Moving K eys
You can use the time slider to move one Biped key
past another. The result is as if the original key
were deleted from its original frame and copied
to the new frame. Simply drag the key to the new
frame,thenreleasethemousetocompletethe
move. The key’s var ious Biped properties (ease
values,TCBvalues,IKblend,andsoon)arenot
changed.
You can move a key past either the following key
or the previous one. You can also mov e it past
multiple keys. If you move a key onto a frame
where a key is a lready present, it replaces the
original key.
In Track View, you can move a key past another
using the transform track. You can also scale
keysforwardintimesuchthatsomekeysarenow
past the keys that weren’t scaled. If keys move
into negative time, a warning reminds you that
keys in negative frames can’t be used for footstep
animation: a workaround is to set new keys in the
negative frames, instead of moving existing ones.
If you change the key to Euler control (on the
Quaternion/Euler rollout) and then drag it past
another, the key’s tangent type is maintained.
If you add a layer (on the Layers rollout), set two
keys, and then move the first one past the second
one, this also works.
Freeform Animation
Itislefttoyoutocreateallthekeysinafreeform
animation ; Biped Dynamics is not ac tive and does
not recalculate body position. Balance Factor
is active in a freeform animation. A completely
freeform animation contains no footsteps.
To start an entirely freeform animation, simply
create a biped and beg in key framing.
Note: Once you initiate a freeform animation, you
cannot add footsteps to it in Footstep mode. You
can, however, convert your freeform animation to
a footstep animation using Convert on the Biped
rollout.
You will often want a freeform period in a footstep
sequence;forawalkthenfalltypeofmotionfor