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/******************************************************************************
* SOFA, Simulation Open-Framework Architecture, version 1.0 beta 4 *
* (c) 2006-2009 MGH, INRIA, USTL, UJF, CNRS *
* *
* This library is free software; you can redistribute it and/or modify it *
* under the terms of the GNU Lesser General Public License as published by *
* the Free Software Foundation; either version 2.1 of the License, or (at *
* your option) any later version. *
* *
* This library is distributed in the hope that it will be useful, but WITHOUT *
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or *
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License *
* for more details. *
* *
* You should have received a copy of the GNU Lesser General Public License *
* along with this library; if not, write to the Free Software Foundation, *
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *
*******************************************************************************
* SOFA :: Modules *
* *
* Authors: The SOFA Team and external contributors (see Authors.txt) *
* *
* Contact information: contact@sofa-framework.org *
******************************************************************************/
#ifndef SOFA_COMPONENT_FORCEFIELD_TRIANGULARFEMFORCEFIELD_H
#define SOFA_COMPONENT_FORCEFIELD_TRIANGULARFEMFORCEFIELD_H
#if !defined(__GNUC__) || (__GNUC__ > 3 || (_GNUC__ == 3 && __GNUC_MINOR__ > 3))
#pragma once
#endif
#include <sofa/core/componentmodel/behavior/ForceField.h>
#include <sofa/core/componentmodel/topology/BaseMeshTopology.h>
#include <sofa/defaulttype/VecTypes.h>
#include <sofa/defaulttype/Mat.h>
#include <sofa/component/topology/TriangleData.h>
#include <sofa/component/topology/EdgeData.h>
#include <sofa/component/topology/PointData.h>
#include <newmat/newmat.h>
#include <newmat/newmatap.h>
namespace sofa
{
namespace component
{
namespace forcefield
{
using namespace sofa::defaulttype;
using sofa::helper::vector;
using namespace sofa::component::topology;
/** corotational triangle from
* @InProceedings{NPF05,
* author = "Nesme, Matthieu and Payan, Yohan and Faure, Fran\c{c}ois",
* title = "Efficient, Physically Plausible Finite Elements",
* booktitle = "Eurographics (short papers)",
* month = "august",
* year = "2005",
* editor = "J. Dingliana and F. Ganovelli",
* keywords = "animation, physical model, elasticity, finite elements",
* url = "http://www-evasion.imag.fr/Publications/2005/NPF05"
* }
*/
template<class DataTypes>
class TriangularFEMForceField : public core::componentmodel::behavior::ForceField<DataTypes>, public virtual core::objectmodel::BaseObject
{
public:
typedef core::componentmodel::behavior::ForceField<DataTypes> Inherited;
typedef typename DataTypes::VecCoord VecCoord;
typedef typename DataTypes::VecDeriv VecDeriv;
typedef typename DataTypes::VecReal VecReal;
typedef VecCoord Vector;
typedef typename DataTypes::Coord Coord ;
typedef typename DataTypes::Deriv Deriv ;
typedef typename Coord::value_type Real ;
typedef sofa::core::componentmodel::topology::BaseMeshTopology::index_type Index;
typedef sofa::core::componentmodel::topology::BaseMeshTopology::Triangle Element;
typedef sofa::core::componentmodel::topology::BaseMeshTopology::SeqTriangles VecElement;
static const int SMALL = 1; ///< Symbol of small displacements triangle solver
static const int LARGE = 0; ///< Symbol of large displacements triangle solver
protected:
bool _anisotropicMaterial; // used to turn on / off optimizations
typedef Vec<6, Real> Displacement; ///< the displacement vector
typedef Mat<3, 3, Real> MaterialStiffness; ///< the matrix of material stiffness
typedef sofa::helper::vector<MaterialStiffness> VecMaterialStiffness; ///< a vector of material stiffness matrices
typedef Mat<6, 3, Real> StrainDisplacement; ///< the strain-displacement matrix
typedef sofa::helper::vector<StrainDisplacement> VecStrainDisplacement; ///< a vector of strain-displacement matrices
typedef Mat<3, 3, Real > Transformation; ///< matrix for rigid transformations like rotations
class TriangleInformation
{
public:
/// material stiffness matrices of each tetrahedron
MaterialStiffness materialMatrix;
///< the strain-displacement matrices vector
StrainDisplacement strainDisplacementMatrix;
// large displacement method
helper::fixed_array<Coord,3> rotatedInitialElements;
Transformation rotation;
// strain vector
Vec<3,Real> strain;
// stress vector
Vec<3,Real> stress;
Transformation initialTransformation;
Coord principalStressDirection;
Real maxStress;
Coord principalStrainDirection;
Real maxStrain;
TriangleInformation() { }
/// Output stream
inline friend std::ostream& operator<< ( std::ostream& os, const TriangleInformation& /*ti*/ )
{
return os;
}
/// Input stream
inline friend std::istream& operator>> ( std::istream& in, TriangleInformation& /*ti*/ )
{
return in;
}
};
class EdgeInformation
{
public:
EdgeInformation()
:fracturable(false){};
bool fracturable;
/// Output stream
inline friend std::ostream& operator<< ( std::ostream& os, const EdgeInformation& /*ei*/ )
{
return os;
}
/// Input stream
inline friend std::istream& operator>> ( std::istream& in, EdgeInformation& /*ei*/ )
{
return in;
}
};
class VertexInformation
{
public:
VertexInformation()
:sumEigenValues(0.0){};
Coord meanStrainDirection;
double sumEigenValues;
/// Output stream
inline friend std::ostream& operator<< ( std::ostream& os, const VertexInformation& /*vi*/)
{
return os;
}
/// Input stream
inline friend std::istream& operator>> ( std::istream& in, VertexInformation& /*vi*/)
{
return in;
}
};
TriangleData<TriangleInformation> triangleInfo;
PointData<VertexInformation> vertexInfo;
EdgeData<EdgeInformation> edgeInfo;
sofa::core::componentmodel::topology::BaseMeshTopology* _topology;
//const VecElement *_indexedElements;
//Data< VecCoord > _initialPoints; ///< the intial positions of the points
VecCoord* _initialPoints;
// int _method; ///< the computation method of the displacements
bool updateMatrix;
int lastFracturedEdgeIndex;
public:
TriangularFEMForceField();
//virtual const char* getTypeName() const { return "TriangularFEMForceField"; }
virtual ~TriangularFEMForceField();
virtual void init();
virtual void reinit();
virtual void addForce (VecDeriv& f, const VecCoord& x, const VecDeriv& v);
virtual void addDForce (VecDeriv& df, const VecDeriv& dx);
virtual double getPotentialEnergy(const VecCoord& x);
virtual void handleTopologyChange();
void draw();
int method;
Data<std::string> f_method;
Data<Real> f_poisson;
Data<Real> f_young;
Data<Real> f_damping;
Data<bool> f_fracturable;
Data<bool> showStressValue;
Data<bool> showStressVector;
Real getPoisson() { return f_poisson.getValue(); }
void setPoisson(Real val) { f_poisson.setValue(val); }
Real getYoung() { return f_young.getValue(); }
void setYoung(Real val) { f_young.setValue(val); }
Real getDamping() { return f_damping.getValue(); }
void setDamping(Real val) { f_damping.setValue(val); }
int getMethod() { return method; }
void setMethod(int val) { method = val; }
int getFracturedEdge();
void getFractureCriteria(int element, Deriv& direction, Real& value);
/// Compute value of stress along a given direction (typically the fiber direction and transverse direction in anisotropic materials)
void computeStressAlongDirection(Real &stress_along_dir, Index elementIndex, const Coord &direction, const Vec<3,Real> &stress);
/// Compute value of stress along a given direction (typically the fiber direction and transverse direction in anisotropic materials)
void computeStressAlongDirection(Real &stress_along_dir, Index elementIndex, const Coord &direction);
/// Compute value of stress across a given direction (typically the fracture direction)
void computeStressAcrossDirection(Real &stress_across_dir, Index elementIndex, const Coord &direction, const Vec<3,Real> &stress);
/// Compute value of stress across a given direction (typically the fracture direction)
void computeStressAcrossDirection(Real &stress_across_dir, Index elementIndex, const Coord &direction);
/// Compute current stress
void computeStress(Vec<3,Real> &stress, Index elementIndex);
protected :
void computeDisplacementSmall(Displacement &D, Index elementIndex, const VecCoord &p);
void computeDisplacementLarge(Displacement &D, Index elementIndex, const Transformation &R_2_0, const VecCoord &p);
void computeStrainDisplacement( StrainDisplacement &J, Coord a, Coord b, Coord c );
void computeStrain(Vec<3,Real> &strain, const StrainDisplacement &J, const Displacement &D);
void computeStress(Vec<3,Real> &stress, MaterialStiffness &K, Vec<3,Real> &strain);
void computeForce(Displacement &F, Index elementIndex, const VecCoord &p);
void computePrincipalStrain(Index elementIndex, Vec<3,Real> &strain);
void computePrincipalStress(Index elementIndex, Vec<3,Real> &stress);
static void TRQSTriangleCreationFunction (int , void* , TriangleInformation &, const Triangle& , const sofa::helper::vector< unsigned int > &, const sofa::helper::vector< double >&);
/// f += Kx where K is the stiffness matrix and x a displacement
virtual void applyStiffness( VecCoord& f, Real h, const VecCoord& x );
virtual void computeMaterialStiffness(int i, Index& a, Index& b, Index& c);
////////////// small displacements method
void initSmall(int i, Index&a, Index&b, Index&c);
void accumulateForceSmall( VecCoord& f, const VecCoord & p, Index elementIndex);
void accumulateDampingSmall( VecCoord& f, Index elementIndex );
void applyStiffnessSmall( VecCoord& f, Real h, const VecCoord& x );
////////////// large displacements method
//sofa::helper::vector< helper::fixed_array <Coord, 3> > _rotatedInitialElements; ///< The initials positions in its frame
//sofa::helper::vector< Transformation > _rotations;
void initLarge(int i, Index&a, Index&b, Index&c);
void computeRotationLarge( Transformation &r, const VecCoord &p, const Index &a, const Index &b, const Index &c);
void accumulateForceLarge( VecCoord& f, const VecCoord & p, Index elementIndex);
void accumulateDampingLarge( VecCoord& f, Index elementIndex );
void applyStiffnessLarge( VecCoord& f, Real h, const VecCoord& x );
};
#if defined(WIN32) && !defined(SOFA_COMPONENT_FORCEFIELD_TRIANGULARFEMFORCEFIELD_CPP)
#pragma warning(disable : 4231)
#ifndef SOFA_FLOAT
extern template class SOFA_COMPONENT_FORCEFIELD_API TriangularFEMForceField<defaulttype::Vec3dTypes>;
#endif
#ifndef SOFA_DOUBLE
extern template class SOFA_COMPONENT_FORCEFIELD_API TriangularFEMForceField<defaulttype::Vec3fTypes>;
#endif
#endif
} // namespace forcefield
} // namespace component
} // namespace sofa
#endif
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