netgenplugin/src/NETGENPlugin/NETGENPlugin_NETGEN_2D_ONLY.cxx

// Copyright (C) 2007-2014  CEA/DEN, EDF R&D, OPEN CASCADE
//
// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
//
// See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
//

// File      : NETGENPlugin_NETGEN_2D_ONLY.cxx
// Author    : Edward AGAPOV (OCC)
// Project   : SALOME
//
#include "NETGENPlugin_NETGEN_2D_ONLY.hxx"

#include "NETGENPlugin_Mesher.hxx"
#include "NETGENPlugin_Hypothesis_2D.hxx"

#include <SMDS_MeshElement.hxx>
#include <SMDS_MeshNode.hxx>
#include <SMESHDS_Mesh.hxx>
#include <SMESH_Comment.hxx>
#include <SMESH_Gen.hxx>
#include <SMESH_Mesh.hxx>
#include <SMESH_MesherHelper.hxx>
#include <SMESH_subMesh.hxx>
#include <StdMeshers_FaceSide.hxx>
#include <StdMeshers_LengthFromEdges.hxx>
#include <StdMeshers_MaxElementArea.hxx>
#include <StdMeshers_QuadranglePreference.hxx>
#include <StdMeshers_ViscousLayers2D.hxx>

#include <Precision.hxx>
#include <Standard_ErrorHandler.hxx>
#include <Standard_Failure.hxx>

#include <utilities.h>

#include <list>
#include <vector>
#include <limits>

/*
  Netgen include files
*/
namespace nglib {
#include <nglib.h>
}
#ifndef OCCGEOMETRY
#define OCCGEOMETRY
#endif
#include <occgeom.hpp>
#include <meshing.hpp>
//#include <meshtype.hpp>
namespace netgen {
#ifdef NETGEN_V5
  extern int OCCGenerateMesh (OCCGeometry&, Mesh*&, MeshingParameters&, int, int);
#else
  extern int OCCGenerateMesh (OCCGeometry&, Mesh*&, int, int, char*);
#endif
  extern MeshingParameters mparam;
}

using namespace std;
using namespace netgen;
using namespace nglib;

//#define DUMP_SEGMENTS

//=============================================================================
/*!
 *  
 */
//=============================================================================

NETGENPlugin_NETGEN_2D_ONLY::NETGENPlugin_NETGEN_2D_ONLY(int hypId, int studyId,
                                                         SMESH_Gen* gen)
  : SMESH_2D_Algo(hypId, studyId, gen)
{
  MESSAGE("NETGENPlugin_NETGEN_2D_ONLY::NETGENPlugin_NETGEN_2D_ONLY");
  _name = "NETGEN_2D_ONLY";
  
  _shapeType = (1 << TopAbs_FACE);// 1 bit /shape type

  _compatibleHypothesis.push_back("MaxElementArea");
  _compatibleHypothesis.push_back("LengthFromEdges");
  _compatibleHypothesis.push_back("QuadranglePreference");
  _compatibleHypothesis.push_back("NETGEN_Parameters_2D");
  _compatibleHypothesis.push_back("ViscousLayers2D");

  _hypMaxElementArea = 0;
  _hypLengthFromEdges = 0;
  _hypQuadranglePreference = 0;
  _hypParameters = 0;
}

//=============================================================================
/*!
 *  
 */
//=============================================================================

NETGENPlugin_NETGEN_2D_ONLY::~NETGENPlugin_NETGEN_2D_ONLY()
{
  MESSAGE("NETGENPlugin_NETGEN_2D_ONLY::~NETGENPlugin_NETGEN_2D_ONLY");
}

//=============================================================================
/*!
 *  
 */
//=============================================================================

bool NETGENPlugin_NETGEN_2D_ONLY::CheckHypothesis (SMESH_Mesh&         aMesh,
                                                   const TopoDS_Shape& aShape,
                                                   Hypothesis_Status&  aStatus)
{
  _hypMaxElementArea = 0;
  _hypLengthFromEdges = 0;
  _hypQuadranglePreference = 0;
  _hypParameters = 0;
  _progressByTic = -1;

  const list<const SMESHDS_Hypothesis*>& hyps = GetUsedHypothesis(aMesh, aShape, false);

  if (hyps.empty())
  {
    aStatus = HYP_OK; //SMESH_Hypothesis::HYP_MISSING;
    return true;  // (PAL13464) can work with no hypothesis, LengthFromEdges is default one
  }

  aStatus = HYP_MISSING;

  bool hasVL = false;
  list<const SMESHDS_Hypothesis*>::const_iterator ith;
  for (ith = hyps.begin(); ith != hyps.end(); ++ith )
  {
    const SMESHDS_Hypothesis* hyp = (*ith);

    string hypName = hyp->GetName();

    if      ( hypName == "MaxElementArea")
      _hypMaxElementArea = static_cast<const StdMeshers_MaxElementArea*> (hyp);
    else if ( hypName == "LengthFromEdges" )
      _hypLengthFromEdges = static_cast<const StdMeshers_LengthFromEdges*> (hyp);
    else if ( hypName == "QuadranglePreference" )
      _hypQuadranglePreference = static_cast<const StdMeshers_QuadranglePreference*>(hyp);
    else if ( hypName == "NETGEN_Parameters_2D" )
      _hypParameters = static_cast<const NETGENPlugin_Hypothesis_2D*>(hyp);
    else if ( hypName == StdMeshers_ViscousLayers2D::GetHypType() )
      hasVL = true;
    else {
      aStatus = HYP_INCOMPATIBLE;
      return false;
    }
  }

  int nbHyps = bool(_hypMaxElementArea) + bool(_hypLengthFromEdges) + bool(_hypParameters );
  if ( nbHyps > 1 )
    aStatus = HYP_CONCURENT;
  else if ( hasVL )
    error( StdMeshers_ViscousLayers2D::CheckHypothesis( aMesh, aShape, aStatus ));
  else
    aStatus = HYP_OK;

  return ( aStatus == HYP_OK );
}

//=============================================================================
/*!
 *Here we are going to use the NETGEN mesher
 */
//=============================================================================

bool NETGENPlugin_NETGEN_2D_ONLY::Compute(SMESH_Mesh&         aMesh,
                                          const TopoDS_Shape& aShape)
{
  netgen::multithread.terminate = 0;
  netgen::multithread.task = "Surface meshing";

  SMESHDS_Mesh* meshDS = aMesh.GetMeshDS();
  int faceID = meshDS->ShapeToIndex( aShape );

  SMESH_MesherHelper helper(aMesh);
  _quadraticMesh = helper.IsQuadraticSubMesh(aShape);
  helper.SetElementsOnShape( true );
  const bool ignoreMediumNodes = _quadraticMesh;

  // build viscous layers if required
  TopoDS_Face F = TopoDS::Face( aShape/*.Oriented( TopAbs_FORWARD )*/);
  if ( F.Orientation() != TopAbs_FORWARD &&
       F.Orientation() != TopAbs_REVERSED )
    F.Orientation( TopAbs_FORWARD ); // avoid pb with TopAbs_INTERNAL
  SMESH_ProxyMesh::Ptr proxyMesh = StdMeshers_ViscousLayers2D::Compute( aMesh, F );
  if ( !proxyMesh )
    return false;

  // ------------------------
  // get all edges of a face
  // ------------------------
  TError problem;
  TSideVector wires =
    StdMeshers_FaceSide::GetFaceWires( F, aMesh, ignoreMediumNodes, problem, proxyMesh );
  if ( problem && !problem->IsOK() )
    return error( problem );
  int nbWires = wires.size();
  if ( nbWires == 0 )
    return error( "Problem in StdMeshers_FaceSide::GetFaceWires()");
  if ( wires[0]->NbSegments() < 3 ) // ex: a circle with 2 segments
    return error(COMPERR_BAD_INPUT_MESH,
                 SMESH_Comment("Too few segments: ")<<wires[0]->NbSegments());

  // --------------------
  // compute edge length
  // --------------------

  NETGENPlugin_Mesher aMesher( &aMesh, aShape, /*isVolume=*/false);
  netgen::OCCGeometry occgeo;
  aMesher.PrepareOCCgeometry( occgeo, F, aMesh );
  occgeo.fmap.Clear(); // face can be reversed, which is wrong in this case (issue 19978)
  occgeo.fmap.Add( F );

  if ( _hypParameters )
  {
    aMesher.SetParameters(_hypParameters);
  }
  else
  {
    double edgeLength = 0;
    if (_hypLengthFromEdges /*|| (!_hypLengthFromEdges && !_hypMaxElementArea)*/)
    {
      int nbSegments = 0;
      for ( int iW = 0; iW < nbWires; ++iW )
      {
        edgeLength += wires[ iW ]->Length();
        nbSegments += wires[ iW ]->NbSegments();
      }
      if ( nbSegments )
        edgeLength /= nbSegments;
    }
    else if ( _hypMaxElementArea )
    {
      double maxArea = _hypMaxElementArea->GetMaxArea();
      edgeLength = sqrt(2. * maxArea/sqrt(3.0));
    }
    else
    {
      // set edgeLength by a longest segment
      double maxSeg2 = 0;
      for ( int iW = 0; iW < nbWires; ++iW )
      {
        const UVPtStructVec& points = wires[ iW ]->GetUVPtStruct();
        gp_Pnt pPrev = SMESH_TNodeXYZ( points[0].node );
        for ( size_t i = 1; i < points.size(); ++i )
        {
          gp_Pnt p = SMESH_TNodeXYZ( points[i].node );
          maxSeg2 = Max( maxSeg2, p.SquareDistance( pPrev ));
          pPrev = p;
        }
      }
      edgeLength = sqrt( maxSeg2 ) * 1.05;
    }
    if ( edgeLength < DBL_MIN )
      edgeLength = occgeo.GetBoundingBox().Diam();

    netgen::mparam.maxh = edgeLength;
    netgen::mparam.minh = aMesher.GetDefaultMinSize( aShape, netgen::mparam.maxh );
    netgen::mparam.quad = _hypQuadranglePreference ? 1 : 0;
    netgen::mparam.grading = 0.4; // Moderate fineness by default
  }
  occgeo.face_maxh = netgen::mparam.maxh;

  // -------------------------
  // Make input netgen mesh
  // -------------------------

  // MESHCONST_ANALYSE step may lead to a failure, so we make an attempt
  // w/o MESHCONST_ANALYSE at the second loop
  int err = 1;
  int iLoop = netgen::mparam.uselocalh ? 0 : 1; // uselocalh depends on 
  for ( ; iLoop < 2; iLoop++ )
  {
    bool isMESHCONST_ANALYSE = false;
    InitComputeError();

    NETGENPlugin_NetgenLibWrapper ngLib;
    netgen::Mesh * ngMesh = (netgen::Mesh*) ngLib._ngMesh;
    ngLib._isComputeOk = false;

#ifndef NETGEN_V5
    char *optstr = 0;
#endif
    int startWith = MESHCONST_ANALYSE;
    int endWith   = MESHCONST_ANALYSE;

    if ( !_hypLengthFromEdges && !_hypMaxElementArea && iLoop == 0 )
    {
      isMESHCONST_ANALYSE = true;
#ifdef NETGEN_V5
      err = netgen::OCCGenerateMesh(occgeo, ngMesh, netgen::mparam, startWith, endWith);
#else
      err = netgen::OCCGenerateMesh(occgeo, ngMesh, startWith, endWith, optstr);
#endif
      ngLib._ngMesh = 0;
      ngLib.setMesh(( nglib::Ng_Mesh*) ngMesh );
    }
    else
    {
      Box<3> bb = occgeo.GetBoundingBox();
      bb.Increase (bb.Diam()/10);
      ngMesh->SetLocalH (bb.PMin(), bb.PMax(), netgen::mparam.grading);
      ngMesh->SetGlobalH (netgen::mparam.maxh);
    }
    //cerr << "max " << netgen::mparam.maxh << " min " << netgen::mparam.minh << endl;

    vector< const SMDS_MeshNode* > nodeVec;
    problem = aMesher.AddSegmentsToMesh( *ngMesh, occgeo, wires, helper, nodeVec );
    if ( problem && !problem->IsOK() )
      return error( problem );

    if ( iLoop == 0 )
    {
      // limit element size near existing segments
      TopTools_IndexedMapOfShape edgeMap;
      PShapeIteratorPtr solidIt = helper.GetAncestors( F, aMesh, TopAbs_SOLID );
      while ( const TopoDS_Shape* solid = solidIt->next() )
      {
        TopExp_Explorer eExp( *solid, TopAbs_EDGE );
        for ( ; eExp.More(); eExp.Next() )
        {
          const TopoDS_Shape& edge = eExp.Current();
          if (( SMESH_Algo::isDegenerated( TopoDS::Edge( edge ))) ||
              ( helper.IsSubShape( edge, aShape )) ||
              ( !edgeMap.Add( edge )))
            continue;
          SMESHDS_SubMesh* smDS = aMesh.GetMeshDS()->MeshElements( edge );
          if ( !smDS ) continue;
          SMDS_ElemIteratorPtr segIt = smDS->GetElements();
          while ( segIt->more() )
          {
            const SMDS_MeshElement* seg = segIt->next();
            SMESH_TNodeXYZ n1 = seg->GetNode(0);
            SMESH_TNodeXYZ n2 = seg->GetNode(1);
            gp_XYZ p = 0.5 * ( n1 + n2 );
            netgen::Point3d pi(p.X(), p.Y(), p.Z());
            ngMesh->RestrictLocalH( pi, Max(( n1 - n2 ).Modulus(), netgen::mparam.minh ));
          }
        }
      }
    }

    // -------------------------
    // Generate surface mesh
    // -------------------------

    startWith = MESHCONST_MESHSURFACE;
    endWith   = MESHCONST_OPTSURFACE;

    netgen::mparam.uselocalh = true; // needed while optimization
    try {
      OCC_CATCH_SIGNALS;

#ifdef NETGEN_V5
      err = netgen::OCCGenerateMesh(occgeo, ngMesh, netgen::mparam, startWith, endWith);
#else
      err = netgen::OCCGenerateMesh(occgeo, ngMesh, startWith, endWith, optstr);
#endif
      if(netgen::multithread.terminate)
        return false;
      if ( err )
        error(SMESH_Comment("Error in netgen::OCCGenerateMesh() at ") << netgen::multithread.task);
    }
    catch (Standard_Failure& ex)
    {
      SMESH_Comment str("Exception in  netgen::OCCGenerateMesh()");
      str << " at " << netgen::multithread.task
          << ": " << ex.DynamicType()->Name();
      if ( ex.GetMessageString() && strlen( ex.GetMessageString() ))
        str << ": " << ex.GetMessageString();
      error(str);
      err = 1;
    }
    catch (...) {
      SMESH_Comment str("Exception in  netgen::OCCGenerateMesh()");
      str << " at " << netgen::multithread.task;
      error(str);
      err = 1;
    }
    if ( err /*&& !isMESHCONST_ANALYSE*/ && iLoop == 0 )
    {
      netgen::mparam.minh = netgen::mparam.maxh;
      netgen::mparam.maxh = 0;
      for ( int iW = 0; iW < wires.size(); ++iW )
      {
        StdMeshers_FaceSidePtr wire = wires[ iW ];
        const vector<UVPtStruct>& uvPtVec = wire->GetUVPtStruct();
        for ( size_t iP = 1; iP < uvPtVec.size(); ++iP )
        {
          SMESH_TNodeXYZ   p( uvPtVec[ iP ].node );
          netgen::Point3d np( p.X(),p.Y(),p.Z());
          double segLen = p.Distance( uvPtVec[ iP-1 ].node );
          double   size = ngMesh->GetH( np );
          netgen::mparam.minh = Min( netgen::mparam.minh, size );
          netgen::mparam.maxh = Max( netgen::mparam.maxh, segLen );
        }
      }
      //cerr << "min " << netgen::mparam.minh << " max " << netgen::mparam.maxh << endl;
      netgen::mparam.minh *= 0.9;
      netgen::mparam.maxh *= 1.1;

      continue;
    }

    // ----------------------------------------------------
    // Fill the SMESHDS with the generated nodes and faces
    // ----------------------------------------------------

    int nbNodes = ngMesh->GetNP();
    int nbFaces = ngMesh->GetNSE();

    int nbInputNodes = nodeVec.size()-1;
    nodeVec.resize( nbNodes+1, 0 );

    // add nodes
    for ( int ngID = nbInputNodes + 1; ngID <= nbNodes; ++ngID )
    {
      const MeshPoint& ngPoint = ngMesh->Point( ngID );
      SMDS_MeshNode * node = meshDS->AddNode(ngPoint(0), ngPoint(1), ngPoint(2));
      nodeVec[ ngID ] = node;
    }

    // create faces
    const bool reverse = false; //( aShape.Orientation() == TopAbs_REVERSED );
    int i,j;
    for ( i = 1; i <= nbFaces ; ++i )
    {
      const Element2d& elem = ngMesh->SurfaceElement(i);
      vector<const SMDS_MeshNode*> nodes( elem.GetNP() );
      for (j=1; j <= elem.GetNP(); ++j)
      {
        int pind = elem.PNum(j);
        if ( pind < 1 )
          break;
        const SMDS_MeshNode* node = nodeVec[ pind ];
        if ( reverse )
          nodes[ nodes.size()-j ] = node;
        else
          nodes[ j-1 ] = node;
        if ( node->GetPosition()->GetTypeOfPosition() == SMDS_TOP_3DSPACE )
        {
          const PointGeomInfo& pgi = elem.GeomInfoPi(j);
          meshDS->SetNodeOnFace((SMDS_MeshNode*)node, faceID, pgi.u, pgi.v);
        }
      }
      if ( j > elem.GetNP() )
      {
        SMDS_MeshFace* face = 0;
        if ( elem.GetType() == TRIG )
          face = helper.AddFace(nodes[0],nodes[1],nodes[2]);
        else
          face = helper.AddFace(nodes[0],nodes[1],nodes[2],nodes[3]);
      }
    }

    ngLib._isComputeOk = !err;
    break;

  } // two attempts

  return !err;
}

void NETGENPlugin_NETGEN_2D_ONLY::CancelCompute()
{
  SMESH_Algo::CancelCompute();
  netgen::multithread.terminate = 1;
}

//================================================================================
/*!
 * \brief Return progress of Compute() [0.,1]
 */
//================================================================================

double NETGENPlugin_NETGEN_2D_ONLY::GetProgress() const
{
  const char* task1 = "Surface meshing";
  //const char* task2 = "Optimizing surface";
  double& progress = const_cast<NETGENPlugin_NETGEN_2D_ONLY*>( this )->_progress;
  if ( _progressByTic < 0. &&
       strncmp( netgen::multithread.task, task1, 3 ) == 0 )
  {
    progress = Min( 0.25, SMESH_Algo::GetProgressByTic() ); // [0, 0.25]
  }
  else //if ( strncmp( netgen::multithread.task, task2, 3 ) == 0)
  {
    if ( _progressByTic < 0 )
    {
      NETGENPlugin_NETGEN_2D_ONLY* me = (NETGENPlugin_NETGEN_2D_ONLY*) this;
      me->_progressByTic = 0.25 / (_progressTic+1);
    }
    const_cast<NETGENPlugin_NETGEN_2D_ONLY*>( this )->_progressTic++;
    progress = Max( progress, _progressByTic * _progressTic );
  }
  //cout << netgen::multithread.task << " " << _progressTic << endl;
  return Min( progress, 0.99 );
}

//=============================================================================
/*!
 *
 */
//=============================================================================

bool NETGENPlugin_NETGEN_2D_ONLY::Evaluate(SMESH_Mesh& aMesh,
                                           const TopoDS_Shape& aShape,
                                           MapShapeNbElems& aResMap)
{
  TopoDS_Face F = TopoDS::Face(aShape);
  if(F.IsNull())
    return false;

  // collect info from edges
  int nb0d = 0, nb1d = 0;
  bool IsQuadratic = false;
  bool IsFirst = true;
  double fullLen = 0.0;
  TopTools_MapOfShape tmpMap;
  for (TopExp_Explorer exp(F, TopAbs_EDGE); exp.More(); exp.Next()) {
    TopoDS_Edge E = TopoDS::Edge(exp.Current());
    if( tmpMap.Contains(E) )
      continue;
    tmpMap.Add(E);
    SMESH_subMesh *aSubMesh = aMesh.GetSubMesh(exp.Current());
    MapShapeNbElemsItr anIt = aResMap.find(aSubMesh);
    if( anIt==aResMap.end() ) {
      SMESH_subMesh *sm = aMesh.GetSubMesh(F);
      SMESH_ComputeErrorPtr& smError = sm->GetComputeError();
      smError.reset( new SMESH_ComputeError(COMPERR_ALGO_FAILED,"Submesh can not be evaluated",this));
      return false;
    }
    std::vector<int> aVec = (*anIt).second;
    nb0d += aVec[SMDSEntity_Node];
    nb1d += Max(aVec[SMDSEntity_Edge],aVec[SMDSEntity_Quad_Edge]);
    double aLen = SMESH_Algo::EdgeLength(E);
    fullLen += aLen;
    if(IsFirst) {
      IsQuadratic = (aVec[SMDSEntity_Quad_Edge] > aVec[SMDSEntity_Edge]);
      IsFirst = false;
    }
  }
  tmpMap.Clear();

  // compute edge length
  double ELen = 0;
  if (_hypLengthFromEdges || !_hypLengthFromEdges && !_hypMaxElementArea) {
    if ( nb1d > 0 )
      ELen = fullLen / nb1d;
  }
  if ( _hypMaxElementArea ) {
    double maxArea = _hypMaxElementArea->GetMaxArea();
    ELen = sqrt(2. * maxArea/sqrt(3.0));
  }
  GProp_GProps G;
  BRepGProp::SurfaceProperties(F,G);
  double anArea = G.Mass();

  const int hugeNb = numeric_limits<int>::max()/10;
  if ( anArea / hugeNb > ELen*ELen )
  {
    SMESH_subMesh *sm = aMesh.GetSubMesh(F);
    SMESH_ComputeErrorPtr& smError = sm->GetComputeError();
    smError.reset( new SMESH_ComputeError(COMPERR_ALGO_FAILED,"Submesh can not be evaluated.\nToo small element length",this));
    return false;
  }
  int nbFaces = (int) ( anArea / ( ELen*ELen*sqrt(3.) / 4 ) );
  int nbNodes = (int) ( ( nbFaces*3 - (nb1d-1)*2 ) / 6 + 1 );
  std::vector<int> aVec(SMDSEntity_Last);
  for(int i=SMDSEntity_Node; i<SMDSEntity_Last; i++) aVec[i]=0;
  if( IsQuadratic ) {
    aVec[SMDSEntity_Node] = nbNodes;
    aVec[SMDSEntity_Quad_Triangle] = nbFaces;
  }
  else {
    aVec[SMDSEntity_Node] = nbNodes;
    aVec[SMDSEntity_Triangle] = nbFaces;
  }
  SMESH_subMesh *sm = aMesh.GetSubMesh(F);
  aResMap.insert(std::make_pair(sm,aVec));

  return true;
}