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1064 Chapter 14: character studio
At this point, you ca n use Conve rt
From Buffer to extract footsteps and reduce
keyframes. Both scale and position adjustments
will be incorporated. Save the motion as an
optimized .bip file.
Sliding Footsteps
Motion-capture and marker data typical ly have
keys at every frame. Filte r ing motion-capture
data reduces keys, making the job of altering or
personalizing the motion data much simpler.
You can create your own library of imported and
optimized motion-capture data by saving .bip files
forusewithothercharactersoraspartofalonger
script in Motion Flow mode. Use a biped that has
no mesh attached to it with Physique. You import
the data, adjust it to your liking , and save it as a .bip
file. You can also run standard .bip fi les through
this filtering process to create loops or to extrac t
footsteps from a freeform animation.
Mo ti on Capt ur e I mport
Footstep motion capture is enabled automatical ly
when importing motion capture data using the
Sliding Tolerance and Sliding Angle controls in
the Motion Capture Conversion Parameters dialog
(page 2–1070).
Footstep Extraction g roup
The following options are active when Footstep
Extraction is on during motion capture
conv ersion.
Ex traction Tolerance—Sets the sensitivity of
footstep ext ract ion. char acter studio determ ines
if the footstep is there by checking that the foot
does not move b eyond the distance determined by
the Extraction Tolerance value. Smaller numbers
are more sensitive and extract more footsteps. The
value is a percentage of foot length.
The default va lue is 0.15. Increase this value to 0.2
or 0.25 if too many footsteps are generated.
Sliding Distance—Creates a sliding footstep (page
2–1064) when positional tolerance is reached.
This value is a percentage of foot length. By default
the foot must slide its own distance (100), before a
sliding footstep is created.
Use this with motion-capture files that contain
sliding feet. A sliding footstep can be created
manually by setting IK Blend > 0 for a biped foot
at a "touch" state key (biped foot first touches a
footstep).
Note: Sliding footsteps display as a footstep with a
line through the center.
Sliding Angle—Creates a sliding footstep (page
2–1064) when rotational tolerance is reached. This
value is in degrees. The default is set high (360
degrees),thefootmustmakeacompleteturn
before a sliding footstep is created.
Use this with motion-capture files that cont ain feet
that pivot, as in a dance motion.
Note: Sliding footsteps display as a footstep with a
line through the center.
Only Ex tr act Footsteps Within Toler ance—Tu rns
on Z -axis Tolerance. These controls filter out
footsteps that do not fall within a given range of
the g round plane. Use this when filtering m otions,
such as hopping or pitching a baseball, in which
a foot might come off the ground and remain
sta tionary, but its position is not intended as a
footstep.
•
Tolerance—Valueisapercentageofleglength.
•
From Z Level—Set a Z v alue (ground).
Flatten Footsteps to Z=0—Moves extracted
footsteps to Z=0. Use this to flatten out minor
differences in the height of the extracted footsteps.