Spline IK constraint settings

Number of control node: Sets the number of evenly spaced control nodes along the constrained skeleton. You use the control nodes to manipulate the curve and constrained skeleton bones.
Lock control nodes: Locks the control nodes so they cannot be translated.
Control twist axis: Lets you set the twist of the control nodes to the X, Y , or Z axis.
Reverse twist: Lets you reverse the direction of the control node's twist when it is rotated. By default, control nodes twist in the direction of the rotation tool.
Twist Interpolation: Specifies the method used to calculate the twist applied to intermediate joints by interpolating between the twists of the start and end joint. Linear is the default setting.

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