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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 *
******************************************************************************/
#define SOFA_COMPONENT_FORCEFIELD_TRIANGULARANISOTROPICFEMFORCEFIELD_CPP
#include <sofa/component/forcefield/TriangularAnisotropicFEMForceField.h>
#include <sofa/core/componentmodel/behavior/ForceField.inl>
#include <sofa/core/ObjectFactory.h>
#include <sofa/core/componentmodel/topology/BaseMeshTopology.h>
#include <sofa/helper/gl/template.h>
#include <sofa/component/topology/TriangleData.inl>
#include <sofa/component/topology/EdgeData.inl>
#include <sofa/component/topology/PointData.inl>
#include <sofa/helper/system/gl.h>
#include <fstream> // for reading the file
#include <iostream> //for debugging
#include <vector>
#include <algorithm>
#include <sofa/defaulttype/Vec3Types.h>
#include <assert.h>
#ifdef _WIN32
#include <windows.h>
#endif
// #define DEBUG_TRIANGLEFEM
namespace sofa
{
namespace component
{
namespace forcefield
{
using namespace sofa::defaulttype;
using namespace sofa::component::topology;
using namespace core::componentmodel::topology;
SOFA_DECL_CLASS(TriangularAnisotropicFEMForceField)
template <class DataTypes>
TriangularAnisotropicFEMForceField<DataTypes>::TriangularAnisotropicFEMForceField()
: f_young2(initData(&f_young2,(Real)(0.5*Inherited::f_young.getValue()),"transverseYoungModulus","Young modulus along transverse direction"))
, f_theta(initData(&f_theta,(Real)(0.0),"fiberAngle","Fiber angle in global reference frame (in degrees)"))
, f_fiberCenter(initData(&f_fiberCenter,"fiberCenter","Concentric fiber center in global reference frame"))
, showFiber(initData(&showFiber,true,"showFiber","Flag activating rendering of fiber directions within each triangle"))
{
this->_anisotropicMaterial = true;
}
template< class DataTypes>
void TriangularAnisotropicFEMForceField<DataTypes>::TRQSTriangleCreationFunction (int triangleIndex, void* param,
TriangleInformation &/*tinfo*/,
const Triangle& /*t*/,
const sofa::helper::vector< unsigned int > &,
const sofa::helper::vector< double >&)
{
TriangularAnisotropicFEMForceField<DataTypes> *ff= (TriangularAnisotropicFEMForceField<DataTypes> *)param;
if (ff) {
const Triangle &t = ff->_topology->getTriangle(triangleIndex);
Index a = t[0];
Index b = t[1];
Index c = t[2];
switch(ff->method)
{
case SMALL :
ff->initSmall(triangleIndex,a,b,c);
ff->computeMaterialStiffness(triangleIndex, a, b, c);
break;
case LARGE :
ff->initLarge(triangleIndex,a,b,c);
ff->computeMaterialStiffness(triangleIndex, a, b, c);
break;
}
}
}
template< class DataTypes>
void TriangularAnisotropicFEMForceField<DataTypes>::init()
{
_topology = getContext()->getMeshTopology();
Inherited::init();
//reinit();
}
template <class DataTypes>void TriangularAnisotropicFEMForceField<DataTypes>::reinit()
{
localFiberDirection.beginEdit();
f_poisson2.setValue(Inherited::f_poisson.getValue()*(f_young2.getValue()/Inherited::f_young.getValue()));
helper::vector<Deriv>& lfd = *(localFiberDirection.beginEdit());
lfd.resize(_topology->getNbTriangles());
localFiberDirection.endEdit();
Inherited::reinit();
}
template <class DataTypes>void TriangularAnisotropicFEMForceField<DataTypes>::handleTopologyChange()
{
std::list<const TopologyChange *>::const_iterator itBegin=_topology->firstChange();
std::list<const TopologyChange *>::const_iterator itEnd=_topology->lastChange();
localFiberDirection.handleTopologyEvents(itBegin,itEnd);
Inherited::handleTopologyChange();
}
template <class DataTypes>
void TriangularAnisotropicFEMForceField<DataTypes>::getFiberDir(int element, Deriv& dir)
{
helper::vector<Deriv>& lfd = *(localFiberDirection.beginEdit());
if ((unsigned)element < lfd.size())
{
const Deriv& ref = lfd[element];
const VecCoord& x = *this->mstate->getX();
topology::Triangle t = _topology->getTriangle(element);
dir = (x[t[1]]-x[t[0]])*ref[0] + (x[t[2]]-x[t[0]])*ref[1];
}
else
{
dir.clear();
}
localFiberDirection.endEdit();
}
template <class DataTypes>
void TriangularAnisotropicFEMForceField<DataTypes>::computeMaterialStiffness(int i, Index& v1, Index& v2, Index& v3)
{
Real Q11, Q12, Q22, Q66;
Coord fiberDirGlobal; // orientation of the fiber in the global frame of reference
Coord fiberDirLocalOrtho; // // orientation of the fiber in the local orthonormal frame of the element
Mat<3,3,Real> T, Tinv;
helper::vector<TriangleInformation>& triangleInf = *(Inherited::triangleInfo.beginEdit());
TriangleInformation *tinfo = &triangleInf[i];
Q11 = Inherited::f_young.getValue()/(1-Inherited::f_poisson.getValue()*f_poisson2.getValue());
Q12 = Inherited::f_poisson.getValue()*f_young2.getValue()/(1-Inherited::f_poisson.getValue()*f_poisson2.getValue());
Q22 = f_young2.getValue()/(1-Inherited::f_poisson.getValue()*f_poisson2.getValue());
Q66 = (Real)(Inherited::f_young.getValue() / (2.0*(1 + Inherited::f_poisson.getValue())));
//if (i >= (int) localFiberDirection.size())
// localFiberDirection.resize(i+1);
T[0] = (*Inherited::_initialPoints)[v2]-(*Inherited::_initialPoints)[v1];
T[1] = (*Inherited::_initialPoints)[v3]-(*Inherited::_initialPoints)[v1];
T[2] = cross(T[0], T[1]);
if (!f_fiberCenter.getValue().empty()) // in case we have concentric fibers
{
Coord tcenter = ((*Inherited::_initialPoints)[v1]+(*Inherited::_initialPoints)[v2]+(*Inherited::_initialPoints)[v3])*(Real)(1.0/3.0);
Coord fcenter = f_fiberCenter.getValue()[0];
fiberDirGlobal = cross(T[2], fcenter-tcenter); // was fiberDir
}
else // for unidirectional fibers
{
double theta = (double)f_theta.getValue()*M_PI/180.0;
fiberDirGlobal = Coord((Real)cos(theta), (Real)sin(theta), 0); // was fiberDir
}
helper::vector<Deriv>& lfd = *(localFiberDirection.beginEdit());
Deriv& fiberDirLocal = lfd[i]; // orientation of the fiber in the local frame of the element (orthonormal frame)
//[1] = cross(T[2], T[0]);
//T[0].normalize();
//T[1].normalize();
//T[2].normalize();
T.transpose();
Tinv.invert(T);
fiberDirLocal = Tinv * fiberDirGlobal;
fiberDirLocal[2] = 0;
fiberDirLocal.normalize();
T[0] = (*Inherited::_initialPoints)[v2]-(*Inherited::_initialPoints)[v1];
T[1] = (*Inherited::_initialPoints)[v3]-(*Inherited::_initialPoints)[v1];
T[2] = cross(T[0], T[1]);
T[1] = cross(T[2], T[0]);
T[0].normalize();
T[1].normalize();
T[2].normalize();
T.transpose();
Tinv.invert(T);
fiberDirLocalOrtho = Tinv * fiberDirGlobal;
fiberDirLocalOrtho[2] = 0;
fiberDirLocalOrtho.normalize();
Real c, s, c2, s2, c3, s3,c4, s4;
c = fiberDirLocalOrtho[0];
s = fiberDirLocalOrtho[1];
c2 = c*c;
s2 = s*s;
c3 = c2*c;
s3 = s2*s;
s4 = s2*s2;
c4 = c2*c2;
// K(1,1)=Q11*COS(THETA)^4 * + 2.0*(Q12+2*Q66)*SIN(THETA)^2*COS(THETA)^2 + Q22*SIN(THETA)^4 => c4*Q11+2*s2*c2*(Q12+2*Q66)+s4*Q22
// K(1,2)=(Q11+Q22-4*Q66)*SIN(THETA)^2*COS(THETA)^2 + Q12*(SIN(THETA)^4+COS(THETA)^4) => s2*c2*(Q11+Q22-4*Q66) + (s4+c4)*Q12
// K(2,1)=K(1,2)
// K(2,2)=Q11*SIN(THETA)^4 + 2.0*(Q12+2*Q66)*SIN(THETA)^2*COS(THETA)^2 + Q22*COS(THETA)^4 => s4*Q11 + 2.0*s2*c2*(Q12+2*Q66) + c4*Q22
// K(6,1)=(Q11-Q12-2*Q66)*SIN(THETA)*COS(THETA)^3 + (Q12-Q22+2*Q66)*SIN(THETA)^3*COS(THETA) => s*c3*(Q11-Q12-2*Q66)+s3*c*(Q12-Q22+2*Q66)
// K(1,6)=K(6,1)
// K(6,2)=(Q11-Q12-2*Q66)*SIN(THETA)^3*COS(THETA)+(Q12-Q22+2*Q66)*SIN(THETA)*COS(THETA)^3 => (Q11-Q12-2*Q66)*s3*c + (Q12-Q22+2*Q66)*s*c3
// K(2,6)=K(6,2)
// K(6,6)=(Q11+Q22-2*Q12-2*Q66)*SIN(THETA)^2 * COS(THETA)^2+ Q66*(SIN(THETA)^4+COS(THETA)^4) => (Q11+Q22-2*Q12-2*Q66)*s2*c2+ Q66*(s4+c4)
Real K11= c4 * Q11 + 2 * c2 * s2 * (Q12+2*Q66) + s4 * Q22;
Real K12 = c2 * s2 * (Q11+Q22-4*Q66) + (c4+s4) * Q12;
Real K22 = s4* Q11 + 2 * c2 * s2 * (Q12+2*Q66) + c4 * Q22;
Real K16 = s * c3 * (Q11-Q12-2*Q66) + s3 * c * (Q12-Q22+2*Q66);
Real K26 = s3 * c * (Q11-Q12-2*Q66) + s * c3 * (Q12-Q22+2*Q66);
Real K66 = c2 * s2 * (Q11+Q22-2*Q12-2*Q66) + (c4+s4) * Q66;
tinfo->materialMatrix[0][0] = K11;
tinfo->materialMatrix[0][1] = K12;
tinfo->materialMatrix[0][2] = K16;
tinfo->materialMatrix[1][0] = K12;
tinfo->materialMatrix[1][1] = K22;
tinfo->materialMatrix[1][2] = K26;
tinfo->materialMatrix[2][0] = K16;
tinfo->materialMatrix[2][1] = K26;
tinfo->materialMatrix[2][2] = K66;
tinfo->materialMatrix *= (Real)(1.0/12.0);
//sout << "Young1=" << Inherited::f_young.getValue() << endl;
//sout << "Young2=" << f_young2.getValue() << endl;
//sout << "Poisson1=" << Inherited::f_poisson.getValue() << endl;
//sout << "Poisson2=" << f_poisson2.getValue() << endl;
localFiberDirection.endEdit();
Inherited::triangleInfo.endEdit();
}
// ----------------------------------------------------------------
// --- Display
// ----------------------------------------------------------------
template <class DataTypes>
void TriangularAnisotropicFEMForceField<DataTypes>::draw()
{
glPolygonOffset(1.0, 2.0);
glEnable(GL_POLYGON_OFFSET_FILL);
Inherited::draw();
glDisable(GL_POLYGON_OFFSET_FILL);
if (!getContext()->getShowForceFields())
return;
helper::vector<Deriv>& lfd = *(localFiberDirection.beginEdit());
if (showFiber.getValue() && lfd.size() >= (unsigned)_topology->getNbTriangles()) {
const VecCoord& x = *this->mstate->getX();
int nbTriangles=_topology->getNbTriangles();
glColor3f(0,0,0);
glBegin(GL_LINES);
for(int i=0;i<nbTriangles; ++i) {
Index a = _topology->getTriangle(i)[0];
Index b = _topology->getTriangle(i)[1];
Index c = _topology->getTriangle(i)[2];
/*
Mat<3,3,Real> T;
T[0] = (*Inherited::_initialPoints)[b]-(*Inherited::_initialPoints)[a];
T[1] = (*Inherited::_initialPoints)[c]-(*Inherited::_initialPoints)[a];
T[2] = cross(T[0], T[1]);
T[1] = cross(T[2], T[0]);
T[1].normalize();
Coord y = T[1];
Coord ab = (*Inherited::_initialPoints)[b]-(*Inherited::_initialPoints)[a];
y *= ab.norm();*/
Coord center = (x[a]+x[b]+x[c])/3;
//Coord d = (x[b]-x[a])*localFiberDirection[i][0] + y*localFiberDirection[i][1];
Coord d = (x[b]-x[a])*lfd[i][0] + (x[c]-x[a])*lfd[i][1];
d*=0.25;
helper::gl::glVertexT(center-d);
helper::gl::glVertexT(center+d);
//Coord testDir(1, 0, 0);
//Real s;
//computeStressAlongDirection(s, i, testDir, Inherited::triangleInfo[i].stress);
}
glEnd();
}
localFiberDirection.endEdit();
}
// Register in the Factory
int TriangularAnisotropicFEMForceFieldClass = core::RegisterObject("Triangular finite element model using anisotropic material")
#ifndef SOFA_FLOAT
.add< TriangularAnisotropicFEMForceField<Vec3dTypes> >()
#endif
#ifndef SOFA_DOUBLE
.add< TriangularAnisotropicFEMForceField<Vec3fTypes> >()
#endif
;
#ifndef SOFA_FLOAT
template class SOFA_COMPONENT_FORCEFIELD_API TriangularAnisotropicFEMForceField<Vec3dTypes>;
#endif
#ifndef SOFA_DOUBLE
template class SOFA_COMPONENT_FORCEFIELD_API TriangularAnisotropicFEMForceField<Vec3fTypes>;
#endif
} // namespace forcefield
} // namespace component
} // namespace sofa
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