8

Understanding Footstep and Body Keys 725
keys to part of the animation, you might want to
deactivate only a portion of the footsteps.
When some but not all footsteps are currently
deactivated, limitations are imposed on the
changes you can make to footsteps:
• You cannot set, delete, move, or edit keys in any
way; footstep tracks are disabled in the Dope
Sheet.
• You can create footsteps only when the new
footsteps are among and adjacent to existing
inactive footsteps.
• Youcandeleteonlyinactivefootsteps,andat
least one inactive footstep must remain.
• You cannot deactivate a set of nonsequential
footsteps.
See also
Activating Footsteps (page 2–723)
Unders tanding Footstep and B ody
Keys
When you activate footsteps, keys are created for
biped body parts. Before you work with footstep
placement and timing, it’s essential that you
understand the default keys generated and how
they relate to footstep editing.
Leg St at es
A leg moving through a footstep has four states,
beginning with the foot on the ground. Then the
foot lifts, moves through the air , and returns to
the ground again. T hese
leg states are labeled by
character studio to help you work with footsteps
and leg/foot keys more easily when editing
footsteps.
These states are referred to in these topics to aid in
understanding more advanced footstep concepts,
so it’s important that you become familiar wit h
them.
• Touch occurs at the leg keyframe where the
foot first touches the footstep, and always
corresponds with the start frame of a footstep
in Track View. The Touch state is always one
frame long.
• Plant occurs after touching, and before lifting.
It is always in between the start and end frames
ofafootstepinTrackView.ThePlantstateis
usually more than one frame long.
• Lift occursatthekeyframewherethefootlifts
off the ground, and always corresponds with
the end frame of a footstep in Track View. The
Liftstateisalwaysoneframelong.
• Move occurs while the foot is in the air, and
is always in the intervals between footsteps in
Track View. I n walking, while one foot moves,
the body is supported by the other leg. In
running or jumping, there are periods where
thebodyisnotsupportedandmovesinmidair.
For more information on these k eys, see
Editing
Footstep Timing (page 2–727)
.
You can d isplay the current state of each leg
by turning on Leg States in Biped rollout > Display
group. The state name appears in viewports near
the foot, corresponding to the state at the current
frame.
Note: State names appear only on f ootsteps that
have been previously activated. If ac tive footsteps
have been deactivated and edited, the state names
that appear will correspond to states the legs were
in
before deactivation. For this reason, leg states
displayed between deactivation and react ivation
might not be accurate.
Regardless of the footstep p attern, activating
footstepswillalwayscauselegkeystobegenerated
at each lift and touch fr ame. Although you can
alter these keys to some degree by going to a