.. _program_listing_file_SPlisHSPlasH_Viscosity_Viscosity_Weiler2018.h:

Program Listing for File Viscosity_Weiler2018.h
===============================================

|exhale_lsh| :ref:`Return to documentation for file <file_SPlisHSPlasH_Viscosity_Viscosity_Weiler2018.h>` (``SPlisHSPlasH/Viscosity/Viscosity_Weiler2018.h``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   #ifndef __Viscosity_Weiler2018_h__
   #define __Viscosity_Weiler2018_h__
   
   #include "SPlisHSPlasH/Common.h"
   #include "SPlisHSPlasH/FluidModel.h"
   #include "SPlisHSPlasH/NonPressureForceBase.h"
   #include "SPlisHSPlasH/Utilities/MatrixFreeSolver.h"
   
   #define USE_BLOCKDIAGONAL_PRECONDITIONER
   
   namespace SPH
   {
       class Viscosity_Weiler2018 : public NonPressureForceBase
       {
       protected:
           Real m_viscosity;
           Real m_boundaryViscosity;
           unsigned int m_maxIter;
           Real m_maxError;
           unsigned int m_iterations;
           std::vector<Vector3r> m_vDiff;
           Real m_tangentialDistanceFactor;
   
   #ifdef USE_BLOCKDIAGONAL_PRECONDITIONER
           typedef Eigen::ConjugateGradient<MatrixReplacement, Eigen::Lower | Eigen::Upper, BlockJacobiPreconditioner3D> Solver;
           FORCE_INLINE static void diagonalMatrixElement(const unsigned int row, Matrix3r &result, void *userData);
   #else
           typedef Eigen::ConjugateGradient<MatrixReplacement, Eigen::Lower | Eigen::Upper, JacobiPreconditioner3D> Solver;
           FORCE_INLINE static void diagonalMatrixElement(const unsigned int row, Vector3r &result, void *userData);
   #endif  
           Solver m_solver;
   
   
           virtual void initParameters();
           
       public:
           static std::string METHOD_NAME;
           static int VISCOSITY_COEFFICIENT;
           static int ITERATIONS;
           static int MAX_ITERATIONS;
           static int MAX_ERROR;
           static int VISCOSITY_COEFFICIENT_BOUNDARY;
   
           Viscosity_Weiler2018(FluidModel *model);
           virtual ~Viscosity_Weiler2018(void);
   
           static NonPressureForceBase* creator(FluidModel* model) { return new Viscosity_Weiler2018(model); }
           virtual std::string getMethodName() { return METHOD_NAME; }
   
           virtual void step();
           virtual void reset();
   
           virtual void performNeighborhoodSearchSort();
   
           static void matrixVecProd(const Real* vec, Real *result, void *userData);
   
           FORCE_INLINE const Vector3r& getVDiff(const unsigned int i) const
           {
               return m_vDiff[i];
           }
   
           FORCE_INLINE Vector3r& getVDiff(const unsigned int i)
           {
               return m_vDiff[i];
           }
   
           FORCE_INLINE void setVDiff(const unsigned int i, const Vector3r& val)
           {
               m_vDiff[i] = val;
           }
   
           void computeRHS(VectorXr &b, VectorXr &g);
   
           void applyForces(const VectorXr &x);
       };
   }
   
   #endif