Motion-capture and marker data typically have keys at every frame. Filtering 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 for use with other characters or as part of a longer 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 files through this filtering process to create loops or to extract footsteps from a freeform animation.
Motion Capture Import
Footstep motion capture is enabled automatically when importing motion capture data using the Sliding Tolerance and Sliding Angle controls in the Motion Capture Conversion Parameters dialog.
Footstep Extraction group
The following options are active when Footstep Extraction is on during motion capture conversion.
- Extraction Tolerance
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Sets the sensitivity of footstep extraction. Biped determines if the footstep is there by checking that the foot does not move beyond 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 value is 0.15. Increase this value to 0.2 or 0.25 if too many footsteps are generated.
- Sliding Distance
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Creates a sliding footstep 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
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Creates a sliding footstep when rotational tolerance is reached. This value is in degrees. The default is set high (360 degrees), the foot must make a complete turn before a sliding footstep is created.
Use this with motion-capture files that contain feet that pivot, as in a dance motion.
Note: Sliding footsteps display as a footstep with a line through the center. - Only Extract Footsteps Within Tolerance
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Turns on Z -axis Tolerance. These controls filter out footsteps that do not fall within a given range of the ground plane. Use this when filtering motions, such as hopping or pitching a baseball, in which a foot might come off the ground and remain stationary, but its position is not intended as a footstep.
- Tolerance Value is a percentage of leg length.
- From Z Level Set a Z value (ground).
- Flatten Footsteps to Z=0
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Moves extracted footsteps to Z=0. Use this to flatten out minor differences in the height of the extracted footsteps.