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Remove Frame Zero: Remove all keys from frame 0. The BVH retargeter creates a T-pose at frame 0 which can be removed with this button.
Remove Unused F-curves: Remove F-curves with a single key, or all keys equal.
Clear Animation: Clear Animation for FK or IK bones.
Set Constraints: Add aggressive constraints to the feet.
Enforce Constraints: Keep all rotations within constraints.
Bend Limbs Positive: Ensure that the limb's X rotation is positive.
Shift Animation: Shift animation globally for selected bones.
Keep FK Feet Above Floor:
Transfer FK => IK:Transfer FK animation to IK bones.
Transfer IK => FK:Transfer IK animation to FK bones.
Keep IK Feet Above Floor: