The body B's initial anchor position defined by the joint's origin and a local offset initialOffset along the joint's Y axis (along the groove).
The groove's length. The groove is from the joint's origin towards length along the joint's local Y axis.
Construct a new instance of GrooveJoint2D. Note: use memnew!GrooveJoint2D instead.
Groove constraint for 2D physics.
This is useful for making a body "slide" through a segment placed in another.