LCPConstraintSolver
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Context: Sofa.Component.Constraint.Lagrangian.Solver

A Constraint Solver using the Linear Complementarity Problem formulation to solve BaseConstraint based components

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
 - displayDebug : Display debug information.
 - initial_guess : activate LCP results history to improve its resolution performances.
 - build_lcp : LCP is not fully built to increase performance in some case.
 - tolerance : residual error threshold for termination of the Gauss-Seidel algorithm
 - maxIt : maximal number of iterations of the Gauss-Seidel algorithm
 - mu : Friction coefficient
 - minW : If not zero, constraints whose self-compliance (i.e. the corresponding value on the diagonal of W) is smaller than this threshold will be ignored
 - maxF : If not zero, constraints whose response force becomes larger than this threshold will be ignored
 - multi_grid : activate multi_grid resolution (NOT STABLE YET)
 - multi_grid_levels : if multi_grid is active: how many levels to create (>=2)
 - merge_method : if multi_grid is active: which method to use to merge constraints (0 = compliance-based, 1 = spatial coordinates)
 - merge_spatial_step : if merge_method is 1: grid size reduction between multigrid levels
 - merge_local_levels : if merge_method is 1: up to the specified level of the multigrid, constraints are grouped locally, i.e. separately within each contact pairs, while on upper levels they are grouped globally independently of contact pairs.
 - constraintForces : OUTPUT: constraint forces (stored only if computeConstraintForces=True)
 - computeConstraintForces : enable the storage of the constraintForces.
 - group : list of ID of groups of constraints to be handled by this solver.
 - graph : Graph of residuals at each iteration
 - showLevels : Number of constraint levels to display
 - showCellWidth : Distance between each constraint cells
 - showTranslation : Position of the first cell
 - showLevelTranslation : Translation between levels

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
 - constraintCorrections : List of constraint corrections handled by this constraint solver