RestShapeSpringsForceField
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Context: Sofa.Component.SolidMechanics.Spring

Elastic springs generating forces on degrees of freedom between their current and rest shape position

Data:
 - name : object name
 - printLog : if true, emits extra messages at runtime.
 - tags : list of the subsets the objet belongs to
 - bbox : this object bounding box
 - componentState : The state of the component among (Dirty, Valid, Undefined, Loading, Invalid).
 - listening : if true, handle the events, otherwise ignore the events
 - isCompliance : Consider the component as a compliance, else as a stiffness
 - rayleighStiffness : Rayleigh damping - stiffness matrix coefficient
 - points : points controlled by the rest shape springs
 - stiffness : stiffness values between the actual position and the rest shape position
 - angularStiffness : angularStiffness assigned when controlling the rotation of the points
 - pivot_points : global pivot points used when translations instead of the rigid mass centers
 - external_points : points from the external Mechancial State that define the rest shape springs
 - recompute_indices : Recompute indices (should be false for BBOX)
 - drawSpring : draw Spring
 - springColor : spring color. (default=[0.0,1.0,0.0,1.0])
 - activeDirections : Directions in which the spring is active (default=[1,1,1])

Links:
 - context : Graph Node containing this object (or BaseContext::getDefault() if no graph is used
 - slaves : Sub-objects used internally by this object
 - master : nullptr for regular objects, or master object for which this object is one sub-objects
 - mechanicalStates : List of mechanical states to which this component is associated
 - mstate : MechanicalState used by this component
 - external_rest_shape : rest_shape can be defined by the position of an external Mechanical State
 - topology : Link to be set to the topology container in the component graph