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994 Chapter 14: character studio
make the biped walk in place. A negative stride
length w i ll make the biped walk backwards.
When a biped walks 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 Str ide Length—Sets the stride length for new
footsteps in 3ds Max units.
ThesamerulesapplyasforParametricStride
Length (described above).
Adjusting Actual Stride Length automatically
changes the value for Parametric Stride Length.
Actual Str ide Height—Sets the rise or fall between
footsteps. You can use this par ameter to create a set
of footsteps going up or down a slope or a stairway.
The value for Actual Stride Height is the difference
in heig ht in units between each of the new
footsteps. Positive values step up and negative
values step dow n .
Stride Height=5 units
Ti me to Nex t Footstep—Specifies the number of
frames in each foot movement cycle. A cycle starts
w ith the frame that a foot touches the ground,
continuesasthefootliftsandmoves,andends
w ith the f rame 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 t hese parameters instead of Auto
Timing to control the speed of the forward motion
over the series of footsteps. However, because
these parameters both affect the footsteps’ time in
contact with the ground, using them to slow down
a walk gives the walk a hesitant, ‘stop-go’ quality.
Walk Footstep—Specifies the number of frames
each footstep will be on the ground during a walk.
The hig her the number, the longer each biped
foot remains in contact with the ground and,
consequently, t he slower the speed of the wa l king
motion.
Footsteps 3 through 5 are on the ground for 22 frames each
Double S uppor t—Specifies the number of frames
both feet will be on the ground at the same time
during a walk.
The higher the number, the longer the period
during which both feet remain in con tact with the
ground during each walk cycle and, consequently,
theslowerthespeedofthewalkingmotion.