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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_TRIANGULARQUADRATICSPRINGSFORCEFIELD_H
#define SOFA_COMPONENT_FORCEFIELD_TRIANGULARQUADRATICSPRINGSFORCEFIELD_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/Vec.h>
#include <sofa/defaulttype/Mat.h>
#include <sofa/component/topology/TriangleData.h>
#include <sofa/component/topology/EdgeData.h>
namespace sofa
{
namespace component
{
namespace forcefield
{
using namespace sofa::helper;
using namespace sofa::defaulttype;
using namespace sofa::component::topology;
template<class DataTypes>
class TriangularQuadraticSpringsForceField : 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::Coord Coord ;
typedef typename DataTypes::Deriv Deriv ;
typedef typename Coord::value_type Real ;
class Mat3 : public fixed_array<Deriv,3>
{
public:
Deriv operator*(const Deriv& v)
{
return Deriv((*this)[0]*v,(*this)[1]*v,(*this)[2]*v);
}
Deriv transposeMultiply(const Deriv& v)
{
return Deriv(v[0]*((*this)[0])[0]+v[1]*((*this)[1])[0]+v[2]*((*this)[2][0]),
v[0]*((*this)[0][1])+v[1]*((*this)[1][1])+v[2]*((*this)[2][1]),
v[0]*((*this)[0][2])+v[1]*((*this)[1][2])+v[2]*((*this)[2][2]));
}
};
protected:
class EdgeRestInformation
{
public:
Real restLength; // the rest length
Real currentLength; // the current edge length
Real dl; // the current unit direction
Real stiffness;
EdgeRestInformation() {
}
/// Output stream
inline friend std::ostream& operator<< ( std::ostream& os, const EdgeRestInformation& /*eri*/ )
{
return os;
}
/// Input stream
inline friend std::istream& operator>> ( std::istream& in, EdgeRestInformation& /*eri*/ )
{
return in;
}
};
class TriangleRestInformation
{
public:
Real gamma[3]; // the angular stiffness
Real stiffness[3]; // the elongation stiffness
Mat3 DfDx[3]; /// the edge stiffness matrix
TriangleRestInformation() {
}
/// Output stream
inline friend std::ostream& operator<< ( std::ostream& os, const TriangleRestInformation& /*tri*/ )
{
return os;
}
/// Input stream
inline friend std::istream& operator>> ( std::istream& in, TriangleRestInformation& /*tri*/ )
{
return in;
}
};
TriangleData<TriangleRestInformation> triangleInfo;
EdgeData<EdgeRestInformation> edgeInfo;
sofa::core::componentmodel::topology::BaseMeshTopology* _topology;
Data< VecCoord > _initialPoints; ///< the intial positions of the points
bool updateMatrix;
Data<Real> f_poissonRatio;
Data<Real> f_youngModulus;
Data<Real> f_dampingRatio;
Data<bool> f_useAngularSprings; // whether angular springs should be included
Real lambda; /// first Lam� coefficient
Real mu; /// second Lam� coefficient
public:
TriangularQuadraticSpringsForceField();
virtual ~TriangularQuadraticSpringsForceField();
virtual double getPotentialEnergy(const VecCoord& x);
virtual void init();
virtual void addForce(VecDeriv& f, const VecCoord& x, const VecDeriv& v);
virtual void addDForce(VecDeriv& df, const VecDeriv& dx);
virtual Real getLambda() const { return lambda;}
virtual Real getMu() const { return mu;}
void setYoungModulus(const double modulus) {
f_youngModulus.setValue((Real)modulus);
}
void setPoissonRatio(const double ratio) {
f_poissonRatio.setValue((Real)ratio);
}
void includeAngularSprings(const bool useAngularSprings) {
f_useAngularSprings.setValue(useAngularSprings);
}
// handle topological changes
virtual void handleTopologyChange();
void draw();
/// compute lambda and mu based on the Young modulus and Poisson ratio
void updateLameCoefficients();
protected :
EdgeData<EdgeRestInformation> &getEdgeInfo() {return edgeInfo;}
static void TRQSEdgeCreationFunction(int edgeIndex, void* param, EdgeRestInformation &ei,
const Edge& , const sofa::helper::vector< unsigned int > &,
const sofa::helper::vector< double >&);
static void TRQSTriangleCreationFunction (int , void* ,
TriangleRestInformation &,
const Triangle& , const sofa::helper::vector< unsigned int > &, const sofa::helper::vector< double >&);
static void TRQSTriangleDestroyFunction ( int , void* , TriangleRestInformation &);
};
} //namespace forcefield
} // namespace Components
} // namespace Sofa
#endif /* _TriangularQuadraticSpringsForceField_H_ */
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