0021422: EDF 1963 SMESH: Viscous layer algorithm fails in some cases (cylindre_partition.py)

fix shrinking on cancave FACEs
This commit is contained in:
eap 2011-11-30 13:49:21 +00:00
parent 3b74875d9a
commit 86b8303fcf

View File

@ -32,16 +32,18 @@
#include "SMESHDS_Hypothesis.hxx"
#include "SMESH_Algo.hxx"
#include "SMESH_ComputeError.hxx"
#include "SMESH_ControlsDef.hxx"
#include "SMESH_Gen.hxx"
#include "SMESH_Group.hxx"
#include "SMESH_Mesh.hxx"
#include "SMESH_MesherHelper.hxx"
#include "SMESH_ProxyMesh.hxx"
#include "SMESH_subMesh.hxx"
#include "SMESH_subMeshEventListener.hxx"
#include "SMESH_ProxyMesh.hxx"
#include "utilities.h"
#include <BRepAdaptor_Curve2d.hxx>
#include <BRep_Tool.hxx>
#include <Bnd_B2d.hxx>
#include <Bnd_B3d.hxx>
@ -56,6 +58,8 @@
#include <Geom_Line.hxx>
#include <Geom_TrimmedCurve.hxx>
#include <Precision.hxx>
#include <Standard_ErrorHandler.hxx>
#include <TColStd_Array1OfReal.hxx>
#include <TopExp.hxx>
#include <TopExp_Explorer.hxx>
#include <TopTools_IndexedMapOfShape.hxx>
@ -67,7 +71,6 @@
#include <gp_Ax1.hxx>
#include <gp_Vec.hxx>
#include <gp_XY.hxx>
#include <gp_XYZ.hxx>
#include <list>
#include <string>
@ -236,6 +239,10 @@ namespace VISCOUS
double d = v1 ^ v2;
return d*refSign > 1e-100;
}
bool IsNeighbour(const _Simplex& other) const
{
return _nPrev == other._nNext || _nNext == other._nPrev;
}
};
//--------------------------------------------------------------------------------
/*!
@ -412,6 +419,7 @@ namespace VISCOUS
Handle(Geom_Surface)& surface,
SMESH_MesherHelper& helper,
const double refSign,
bool isCentroidal,
bool set3D);
};
//--------------------------------------------------------------------------------
@ -445,7 +453,8 @@ namespace VISCOUS
_SolidData& data);
void getSimplices( const SMDS_MeshNode* node, vector<_Simplex>& simplices,
const set<TGeomID>& ingnoreShapes,
const _SolidData* dataToCheckOri = 0);
const _SolidData* dataToCheckOri = 0,
const bool toSort = false);
bool sortEdges( _SolidData& data,
vector< vector<_LayerEdge*> >& edgesByGeom);
void limitStepSize( _SolidData& data,
@ -466,6 +475,7 @@ namespace VISCOUS
bool prepareEdgeToShrink( _LayerEdge& edge, const TopoDS_Face& F,
SMESH_MesherHelper& helper,
const SMESHDS_SubMesh* faceSubMesh );
void fixBadFaces(const TopoDS_Face& F, SMESH_MesherHelper& helper);
bool addBoundaryElements();
bool error( const string& text, int solidID=-1 );
@ -727,6 +737,67 @@ namespace
}
return dir;
}
//================================================================================
/*!
* \brief Returns true if a FACE is bound by a concave EDGE
*/
//================================================================================
bool isConcave( const TopoDS_Face& F, SMESH_MesherHelper& helper )
{
gp_Vec2d drv1, drv2;
gp_Pnt2d p;
TopExp_Explorer eExp( F.Oriented( TopAbs_FORWARD ), TopAbs_EDGE );
for ( ; eExp.More(); eExp.Next() )
{
const TopoDS_Edge& E = TopoDS::Edge( eExp.Current() );
if ( BRep_Tool::Degenerated( E )) continue;
// check if 2D curve is concave
BRepAdaptor_Curve2d curve( E, F );
const int nbIntervals = curve.NbIntervals( GeomAbs_C2 );
TColStd_Array1OfReal intervals(1, nbIntervals + 1 );
curve.Intervals( intervals, GeomAbs_C2 );
bool isConvex = true;
for ( int i = 1; i <= nbIntervals && isConvex; ++i )
{
double u1 = intervals( i );
double u2 = intervals( i+1 );
curve.D2( 0.5*( u1+u2 ), p, drv1, drv2 );
double cross = drv2 ^ drv1;
if ( E.Orientation() == TopAbs_REVERSED )
cross = -cross;
isConvex = ( cross < 1e-9 );
}
// check if concavity is strong enough to care about it
//const double maxAngle = 5 * Standard_PI180;
if ( !isConvex )
{
//cout << "Concave FACE " << helper.GetMeshDS()->ShapeToIndex( F ) << endl;
return true;
// map< double, const SMDS_MeshNode* > u2nodes;
// if ( !SMESH_Algo::GetSortedNodesOnEdge( helper.GetMeshDS(), E,
// /*ignoreMedium=*/true, u2nodes))
// continue;
// map< double, const SMDS_MeshNode* >::iterator u2n = u2nodes.begin();
// gp_Pnt2d uvPrev = helper.GetNodeUV( F, u2n->second );
// double uPrev = u2n->first;
// for ( ++u2n; u2n != u2nodes.end(); ++u2n )
// {
// gp_Pnt2d uv = helper.GetNodeUV( F, u2n->second );
// gp_Vec2d segmentDir( uvPrev, uv );
// curve.D1( uPrev, p, drv1 );
// try {
// if ( fabs( segmentDir.Angle( drv1 )) > maxAngle )
// return true;
// }
// catch ( ... ) {}
// uvPrev = uv;
// uPrev = u2n->first;
// }
}
}
return false;
}
//--------------------------------------------------------------------------------
// DEBUG. Dump intermediate node positions into a python script
#ifdef __myDEBUG
@ -738,31 +809,38 @@ namespace
py = new ofstream(fname);
*py << "from smesh import *" << endl
<< "meshSO = GetCurrentStudy().FindObjectID('0:1:2:3')" << endl
<< "mesh = Mesh( meshSO.GetObject()._narrow( SMESH.SMESH_Mesh ))"<<endl;
<< "mesh = Mesh( meshSO.GetObject() )"<<endl;
}
~PyDump() {
*py << "mesh.MakeGroup('Prisms of viscous layers',VOLUME,FT_ElemGeomType,'=',Geom_PENTA)"
<<endl; delete py; py=0;
void Finish() {
if (py)
*py << "mesh.MakeGroup('Viscous Prisms',VOLUME,FT_ElemGeomType,'=',Geom_PENTA)"<<endl;
delete py; py=0;
}
~PyDump() { Finish(); }
};
#define dumpFunction(f) { _dumpFunction(f, __LINE__);}
#define dumpMove(n) { _dumpMove(n, __LINE__);}
#define dumpCmd(txt) { _dumpCmd(txt, __LINE__);}
void _dumpFunction(const string& fun, int ln)
{ *py<< "def "<<fun<<"(): # "<< ln <<endl; cout<<fun<<"()"<<endl;}
{ if (py) *py<< "def "<<fun<<"(): # "<< ln <<endl; cout<<fun<<"()"<<endl;}
void _dumpMove(const SMDS_MeshNode* n, int ln)
{ *py<< " mesh.MoveNode( "<<n->GetID()<< ", "<< n->X()
{ if (py) *py<< " mesh.MoveNode( "<<n->GetID()<< ", "<< n->X()
<< ", "<<n->Y()<<", "<< n->Z()<< ")\t\t # "<< ln <<endl; }
void _dumpCmd(const string& txt, int ln)
{ *py<< " "<<txt<<" # "<< ln <<endl; }
{ if (py) *py<< " "<<txt<<" # "<< ln <<endl; }
void dumpFunctionEnd()
{ *py<< " return"<< endl; }
{ if (py) *py<< " return"<< endl; }
void dumpChangeNodes( const SMDS_MeshElement* f )
{ if (py) { *py<< " mesh.ChangeElemNodes( " << f->GetID()<<", [";
for ( int i=1; i < f->NbNodes(); ++i ) *py << f->GetNode(i-1)->GetID()<<", ";
*py << f->GetNode( f->NbNodes()-1 )->GetID() << " ])"<< endl; }}
#else
struct PyDump { PyDump() {} };
void dumpFunction(const string& fun ){}
void dumpFunctionEnd() {}
void dumpMove(const SMDS_MeshNode* n ){}
void dumpCmd(const string& txt){}
struct PyDump { void Finish() {} };
#define dumpFunction(f) f
#define dumpMove(n)
#define dumpCmd(txt)
#define dumpFunctionEnd()
#define dumpChangeNodes(f)
#endif
}
@ -906,6 +984,7 @@ SMESH_ComputeErrorPtr _ViscousBuilder::Compute(SMESH_Mesh& theMesh,
addBoundaryElements();
makeGroupOfLE(); // debug
debugDump.Finish();
return _error;
}
@ -1068,11 +1147,16 @@ bool _ViscousBuilder::findFacesWithLayers()
TopoDS_Vertex VV[2];
TopExp::Vertices( TopoDS::Edge( getMeshDS()->IndexToShape( edgeID )),VV[0],VV[1]);
if ( noShrinkVertices.Contains( VV[0] ) || noShrinkVertices.Contains( VV[1] ))
{
_sdVec[i]._noShrinkFaces.insert( getMeshDS()->ShapeToIndex( e2f->second ));
_sdVec[i]._shrinkShape2Shape.erase( e2f++ );
}
else
{
e2f++;
}
}
}
// Find the SHAPE along which to inflate _LayerEdge based on VERTEX
@ -1836,14 +1920,14 @@ void _LayerEdge::SetCosin( double cosin )
void _ViscousBuilder::getSimplices( const SMDS_MeshNode* node,
vector<_Simplex>& simplices,
const set<TGeomID>& ingnoreShapes,
const _SolidData* dataToCheckOri)
const _SolidData* dataToCheckOri,
const bool toSort)
{
SMESH_MeshEditor editor( _mesh );
SMDS_ElemIteratorPtr fIt = node->GetInverseElementIterator(SMDSAbs_Face);
while ( fIt->more() )
{
const SMDS_MeshElement* f = fIt->next();
const TGeomID shapeInd = editor.FindShape( f );
const TGeomID shapeInd = f->getshapeId();
if ( ingnoreShapes.count( shapeInd )) continue;
const int nbNodes = f->NbCornerNodes();
int srcInd = f->GetNodeIndex( node );
@ -1853,7 +1937,25 @@ void _ViscousBuilder::getSimplices( const SMDS_MeshNode* node,
std::swap( nPrev, nNext );
simplices.push_back( _Simplex( nPrev, nNext ));
}
simplices.resize( simplices.size() );
if ( toSort )
{
vector<_Simplex> sortedSimplices( simplices.size() );
sortedSimplices[0] = simplices[0];
int nbFound = 0;
for ( size_t i = 1; i < simplices.size(); ++i )
{
for ( size_t j = 1; j < simplices.size(); ++j )
if ( sortedSimplices[i-1]._nNext == simplices[j]._nPrev )
{
sortedSimplices[i] = simplices[j];
nbFound++;
break;
}
}
if ( nbFound == simplices.size() - 1 )
simplices.swap( sortedSimplices );
}
}
//================================================================================
@ -3447,6 +3549,9 @@ bool _ViscousBuilder::shrink()
}
}
// find out if a FACE is concave
const bool isConcaveFace = isConcave( F, helper );
// Create _SmoothNode's on face F
vector< _SmoothNode > nodesToSmooth( smoothNodes.size() );
{
@ -3456,7 +3561,7 @@ bool _ViscousBuilder::shrink()
const SMDS_MeshNode* n = smoothNodes[i];
nodesToSmooth[ i ]._node = n;
// src nodes must be replaced by tgt nodes to have tgt nodes in _simplices
getSimplices( n, nodesToSmooth[ i ]._simplices, ignoreShapes );
getSimplices( n, nodesToSmooth[ i ]._simplices, ignoreShapes, NULL, isConcaveFace );
// fix up incorrect uv of nodes on the FACE
helper.GetNodeUV( F, n, 0, &isOkUV);
dumpMove( n );
@ -3521,7 +3626,8 @@ bool _ViscousBuilder::shrink()
moved = false;
for ( unsigned i = 0; i < nodesToSmooth.size(); ++i )
{
moved |= nodesToSmooth[i].Smooth( badNb,surface,helper,refSign,/*set3D=*/false );
moved |= nodesToSmooth[i].Smooth( badNb,surface,helper,refSign,
/*isCentroidal=*/isConcaveFace,/*set3D=*/false );
}
if ( badNb < oldBadNb )
nbNoImpSteps = 0;
@ -3532,9 +3638,6 @@ bool _ViscousBuilder::shrink()
}
if ( badNb > 0 )
return error(SMESH_Comment("Can't shrink 2D mesh on face ") << f2sd->first );
if ( !shrinked )
break;
}
// No wrongly shaped faces remain; final smooth. Set node XYZ.
// First, find out a needed quality of smoothing (high for quadrangles only)
@ -3554,11 +3657,14 @@ bool _ViscousBuilder::shrink()
highQuality = ( *nbNodesSet.begin() == 4 );
}
}
if ( !highQuality && isConcaveFace )
fixBadFaces( F, helper ); // fix narrow faces by swaping diagonals
for ( int st = highQuality ? 10 : 3; st; --st )
{
dumpFunction(SMESH_Comment("shrinkFace")<<f2sd->first<<"_st"<<++smooStep); // debug
for ( unsigned i = 0; i < nodesToSmooth.size(); ++i )
nodesToSmooth[i].Smooth( badNb,surface,helper,refSign,/*set3D=*/st==1 );
nodesToSmooth[i].Smooth( badNb,surface,helper,refSign,
/*isCentroidal=*/isConcaveFace,/*set3D=*/st==1 );
dumpFunctionEnd();
}
// Set an event listener to clear FACE sub-mesh together with SOLID sub-mesh
@ -3750,6 +3856,124 @@ bool _ViscousBuilder::prepareEdgeToShrink( _LayerEdge& edge,
// return true;
}
//================================================================================
/*!
* \brief Try to fix triangles with high aspect ratio by swaping diagonals
*/
//================================================================================
void _ViscousBuilder::fixBadFaces(const TopoDS_Face& F, SMESH_MesherHelper& helper)
{
SMESH::Controls::AspectRatio qualifier;
SMESH::Controls::TSequenceOfXYZ points(3), points1(3), points2(3);
const double maxAspectRatio = 4.;
// find bad triangles
vector< const SMDS_MeshElement* > badTrias;
vector< double > badAspects;
SMESHDS_SubMesh* sm = helper.GetMeshDS()->MeshElements( F );
SMDS_ElemIteratorPtr fIt = sm->GetElements();
while ( fIt->more() )
{
const SMDS_MeshElement * f = fIt->next();
if ( f->NbCornerNodes() != 3 ) continue;
for ( int iP = 0; iP < 3; ++iP ) points(iP+1) = SMESH_TNodeXYZ( f->GetNode(iP));
double aspect = qualifier.GetValue( points );
if ( aspect > maxAspectRatio )
{
badTrias.push_back( f );
badAspects.push_back( aspect );
}
}
if ( badTrias.empty() )
return;
// find couples of faces to swap diagonal
typedef pair < const SMDS_MeshElement* , const SMDS_MeshElement* > T2Trias;
vector< T2Trias > triaCouples;
TIDSortedElemSet involvedFaces, emptySet;
for ( size_t iTia = 0; iTia < badTrias.size(); ++iTia )
{
T2Trias trias [3];
double aspRatio [3];
int i1, i2, i3;
involvedFaces.insert( badTrias[iTia] );
for ( int iP = 0; iP < 3; ++iP )
points(iP+1) = SMESH_TNodeXYZ( badTrias[iTia]->GetNode(iP));
// find triangles adjacent to badTrias[iTia] with better aspect ratio after diag-swaping
int bestCouple = -1;
for ( int iSide = 0; iSide < 3; ++iSide )
{
const SMDS_MeshNode* n1 = badTrias[iTia]->GetNode( iSide );
const SMDS_MeshNode* n2 = badTrias[iTia]->GetNode(( iSide+1 ) % 3 );
trias [iSide].first = badTrias[iTia];
trias [iSide].second = SMESH_MeshEditor::FindFaceInSet( n1, n2, emptySet, involvedFaces,
& i1, & i2 );
if ( ! trias[iSide].second || trias[iSide].second->NbCornerNodes() != 3 )
continue;
// aspect ratio of an adjacent tria
for ( int iP = 0; iP < 3; ++iP )
points2(iP+1) = SMESH_TNodeXYZ( trias[iSide].second->GetNode(iP));
double aspectInit = qualifier.GetValue( points2 );
// arrange nodes as after diag-swaping
if ( helper.WrapIndex( i1+1, 3 ) == i2 )
i3 = helper.WrapIndex( i1-1, 3 );
else
i3 = helper.WrapIndex( i1+1, 3 );
points1 = points;
points1( 1+ iSide ) = points2( 1+ i3 );
points2( 1+ i2 ) = points1( 1+ ( iSide+2 ) % 3 );
// aspect ratio after diag-swaping
aspRatio[ iSide ] = qualifier.GetValue( points1 ) + qualifier.GetValue( points2 );
if ( aspRatio[ iSide ] > aspectInit + badAspects[ iTia ] )
continue;
if ( bestCouple < 0 || aspRatio[ bestCouple ] > aspRatio[ iSide ] )
bestCouple = iSide;
}
if ( bestCouple >= 0 )
{
triaCouples.push_back( trias[bestCouple] );
involvedFaces.insert ( trias[bestCouple].second );
}
else
{
involvedFaces.erase( badTrias[iTia] );
}
}
if ( triaCouples.empty() )
return;
// swap diagonals
SMESH_MeshEditor editor( helper.GetMesh() );
dumpFunction(SMESH_Comment("beforeSwapDiagonals_F")<<helper.GetSubShapeID());
for ( size_t i = 0; i < triaCouples.size(); ++i )
{
dumpChangeNodes( triaCouples[i].first );
dumpChangeNodes( triaCouples[i].second );
editor.InverseDiag( triaCouples[i].first, triaCouples[i].second );
}
dumpFunctionEnd();
// just for debug dump resulting triangles
dumpFunction(SMESH_Comment("swapDiagonals_F")<<helper.GetSubShapeID());
for ( size_t i = 0; i < triaCouples.size(); ++i )
{
dumpChangeNodes( triaCouples[i].first );
dumpChangeNodes( triaCouples[i].second );
}
}
//================================================================================
/*!
* \brief Move target node to it's final position on the FACE during shrinking
@ -3843,7 +4067,7 @@ bool _LayerEdge::SetNewLength2d( Handle(Geom_Surface)& surface,
//================================================================================
/*!
* \brief Perform laplacian smooth on the FACE
* \brief Perform smooth on the FACE
* \retval bool - true if the node has been moved
*/
//================================================================================
@ -3852,15 +4076,54 @@ bool _SmoothNode::Smooth(int& badNb,
Handle(Geom_Surface)& surface,
SMESH_MesherHelper& helper,
const double refSign,
bool isCentroidal,
bool set3D)
{
const TopoDS_Face& face = TopoDS::Face( helper.GetSubShape() );
// get uv of surrounding nodes
vector<gp_XY> uv( _simplices.size() );
for ( size_t i = 0; i < _simplices.size(); ++i )
uv[i] = helper.GetNodeUV( face, _simplices[i]._nPrev, _node );
// compute new UV for the node
gp_XY newPos (0,0);
for ( unsigned i = 0; i < _simplices.size(); ++i )
newPos += helper.GetNodeUV( face, _simplices[i]._nPrev, _node );
if ( isCentroidal && _simplices.size() > 3 )
{
// average centers of diagonals wieghted with their reciprocal lengths
if ( _simplices.size() == 4 )
{
double w1 = 1. / ( uv[2]-uv[0] ).SquareModulus();
double w2 = 1. / ( uv[3]-uv[1] ).SquareModulus();
newPos = ( w1 * ( uv[2]+uv[0] ) + w2 * ( uv[3]+uv[1] )) / ( w1+w2 ) / 2;
}
else
{
double sumWeight = 0;
int nb = _simplices.size() == 4 ? 2 : _simplices.size();
for ( int i = 0; i < nb; ++i )
{
int iFrom = i + 2;
int iTo = i + _simplices.size() - 1;
for ( int j = iFrom; j < iTo; ++j )
{
int i2 = SMESH_MesherHelper::WrapIndex( j, _simplices.size() );
double w = 1. / ( uv[i]-uv[i2] ).SquareModulus();
sumWeight += w;
newPos += w * ( uv[i]+uv[i2] );
}
}
newPos /= 2 * sumWeight;
}
}
else
{
// Laplacian smooth
isCentroidal = false;
for ( size_t i = 0; i < _simplices.size(); ++i )
newPos += uv[i];
newPos /= _simplices.size();
}
// count quality metrics (orientation) of triangles around the node
int nbOkBefore = 0;
@ -3873,7 +4136,12 @@ bool _SmoothNode::Smooth(int& badNb,
nbOkAfter += _simplices[i].IsForward( newPos, _node, face, helper, refSign );
if ( nbOkAfter < nbOkBefore )
{
// if ( isCentroidal )
// return Smooth( badNb, surface, helper, refSign, !isCentroidal, set3D );
badNb += _simplices.size() - nbOkBefore;
return false;
}
SMDS_FacePosition* pos = static_cast<SMDS_FacePosition*>( _node->GetPosition() );
pos->SetUParameter( newPos.X() );