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996 Chapter 14: character studio
By interpolating between the two, Biped produces
a footstep ser ies that changes over time.
When Interpolate is cleared, the Last Step
parameters are grayed out. Biped creates all the
footsteps using only the parameters under First
Step.
Start Af ter Last Footstep—Appends the newly
created footsteps to the end of the existing footstep
sequence.
StartatCurrentFrame—Inserts the newly created
footsteps at the current frame after the existing
footstep sequence allow ing you to make a gap in
time b efore the footsteps st art again.
First Step and Last Step
Parametr ic Str ide Length—Sets the stride length for
the new footsteps as a percentage of the length of
thebiped’sleg.Thedefaultvalueof0.75givesan
averagestrideofnormalproportions.
Avalueof1.0willproduceastridelengthequal
to the leg length, which makes the biped stretch
slightly to reach the next step. A value of 0.0 will
makethebipedruninplace. Anegativestride
length will make the biped run backwards.
When a biped r uns backwards, it does not simply
reverse the forward movement but maintains the
correct foot-state sequence with the toe touching
the ground first, followed by the heel.
Adjusting Parametric Stride Length automa tically
changes the value for Actual Stride Length.
Stride Length=0.75 and Stride Length=1
Actual S tr ide Length—Sets the stride leng th for the
new footsteps in 3ds Max units.
The same rules apply as for Parametric Stride
Length (described above).
Adjusting Actual Stride Length automatically
changes the value for Parametric Stride Length.
Stride Height=5 units
Actual Str ide Height—Sets the rise or fall b etween
footsteps. You can use this parameter to create a set
of footsteps going up or down a slope or a stairwa y.
The value for Actua l Stride Height is the difference
in height in units between each of the new
footsteps. Positive va lues step up and negative
values step down.
Ti me to Nex t Footstep—Specifies the number of
frames in each foot movement cycle. A cycle starts
with the frame in which a biped foot touches the
ground, continues as the foot lifts and moves, and
ends with the frame before the foot touches the
ground again. This parameter is only enabled if
Auto Timing is on.
Speed—Displays the number of units the biped
w i ll move per f rame. It changes in response to
changes in the other parameters but cannot be
adjusted directly.
The following two parameters are only enabled
when Auto Timing is off. You can use these
parameters instead of Auto Timing to cont rol the
speed of the forward motion ov er the series of
footsteps.