Base node for all joint constraints in 2D physics. Base node for all joint constraints in 2D physics. Joints take 2 bodies and apply a custom constraint. Return the path to the A node for the joint. Return the path to the B node for the joint. Set the path to the A node for the joint. Must be of type [PhysicsBody2D]. Set the path to the B node for the joint. Must be of type [PhysicsBody2D].