A node for inverse kinematics which may modify more than one bone.
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<description>
Base class of [SkeletonModifier3D]s that has some joint lists and applies inverse kinematics. This class has some structs, enums, and helper methods which are useful to solve inverse kinematics.
If [code]true[/code], the solver retrieves the bone axis from the bone pose every frame.
If [code]false[/code], the solver retrieves the bone axis from the bone rest and caches it, which increases performance slightly, but position changes in the bone pose made before processing this [IKModifier3D] are ignored.