smesh/src/SMESHUtils/SMESH_MeshAlgos.cxx
eap 24fe0efaab IPAL52827: Very few filtering criteria available in filter dialog called from Remove Elements dialog
IPAL52831: Veeery long awaiting for Mesh Information dialog appearance
IPAL52822: Find Elements By Point does not find coincident nodes
IPAL52821: Find Elements By Point dialog: no types available for search if there are only nodes in the mesh
IPAL52823: mesh.GetSubMeshElementsId( subShape ) works wrong if subShape is retrieved indirectly
2015-07-16 20:52:26 +03:00

1669 lines
58 KiB
C++

// Copyright (C) 2007-2015 CEA/DEN, EDF R&D, OPEN CASCADE
//
// Copyright (C) 2003-2007 OPEN CASCADE, EADS/CCR, LIP6, CEA/DEN,
// CEDRAT, EDF R&D, LEG, PRINCIPIA R&D, BUREAU VERITAS
//
// 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 : SMESH_MeshAlgos.hxx
// Created : Tue Apr 30 18:00:36 2013
// Author : Edward AGAPOV (eap)
// This file holds some low level algorithms extracted from SMESH_MeshEditor
// to make them accessible from Controls package
#include "SMESH_MeshAlgos.hxx"
#include "SMDS_FaceOfNodes.hxx"
#include "SMDS_LinearEdge.hxx"
#include "SMDS_Mesh.hxx"
#include "SMDS_PolygonalFaceOfNodes.hxx"
#include "SMDS_VolumeTool.hxx"
#include "SMESH_OctreeNode.hxx"
#include <GC_MakeSegment.hxx>
#include <GeomAPI_ExtremaCurveCurve.hxx>
#include <Geom_Line.hxx>
#include <IntAna_IntConicQuad.hxx>
#include <IntAna_Quadric.hxx>
#include <gp_Lin.hxx>
#include <gp_Pln.hxx>
#include <limits>
#include <numeric>
using namespace std;
//=======================================================================
/*!
* \brief Implementation of search for the node closest to point
*/
//=======================================================================
struct SMESH_NodeSearcherImpl: public SMESH_NodeSearcher
{
//---------------------------------------------------------------------
/*!
* \brief Constructor
*/
SMESH_NodeSearcherImpl( const SMDS_Mesh* theMesh )
{
myMesh = ( SMDS_Mesh* ) theMesh;
TIDSortedNodeSet nodes;
if ( theMesh ) {
SMDS_NodeIteratorPtr nIt = theMesh->nodesIterator(/*idInceasingOrder=*/true);
while ( nIt->more() )
nodes.insert( nodes.end(), nIt->next() );
}
myOctreeNode = new SMESH_OctreeNode(nodes) ;
// get max size of a leaf box
SMESH_OctreeNode* tree = myOctreeNode;
while ( !tree->isLeaf() )
{
SMESH_OctreeNodeIteratorPtr cIt = tree->GetChildrenIterator();
if ( cIt->more() )
tree = cIt->next();
}
myHalfLeafSize = tree->maxSize() / 2.;
}
//---------------------------------------------------------------------
/*!
* \brief Move node and update myOctreeNode accordingly
*/
void MoveNode( const SMDS_MeshNode* node, const gp_Pnt& toPnt )
{
myOctreeNode->UpdateByMoveNode( node, toPnt );
myMesh->MoveNode( node, toPnt.X(), toPnt.Y(), toPnt.Z() );
}
//---------------------------------------------------------------------
/*!
* \brief Do it's job
*/
const SMDS_MeshNode* FindClosestTo( const gp_Pnt& thePnt )
{
map<double, const SMDS_MeshNode*> dist2Nodes;
myOctreeNode->NodesAround( thePnt.Coord(), dist2Nodes, myHalfLeafSize );
if ( !dist2Nodes.empty() )
return dist2Nodes.begin()->second;
list<const SMDS_MeshNode*> nodes;
//myOctreeNode->NodesAround( &tgtNode, &nodes, myHalfLeafSize );
double minSqDist = DBL_MAX;
if ( nodes.empty() ) // get all nodes of OctreeNode's closest to thePnt
{
// sort leafs by their distance from thePnt
typedef map< double, SMESH_OctreeNode* > TDistTreeMap;
TDistTreeMap treeMap;
list< SMESH_OctreeNode* > treeList;
list< SMESH_OctreeNode* >::iterator trIt;
treeList.push_back( myOctreeNode );
gp_XYZ pointNode( thePnt.X(), thePnt.Y(), thePnt.Z() );
bool pointInside = myOctreeNode->isInside( pointNode, myHalfLeafSize );
for ( trIt = treeList.begin(); trIt != treeList.end(); ++trIt)
{
SMESH_OctreeNode* tree = *trIt;
if ( !tree->isLeaf() ) // put children to the queue
{
if ( pointInside && !tree->isInside( pointNode, myHalfLeafSize )) continue;
SMESH_OctreeNodeIteratorPtr cIt = tree->GetChildrenIterator();
while ( cIt->more() )
treeList.push_back( cIt->next() );
}
else if ( tree->NbNodes() ) // put a tree to the treeMap
{
const Bnd_B3d& box = *tree->getBox();
double sqDist = thePnt.SquareDistance( 0.5 * ( box.CornerMin() + box.CornerMax() ));
pair<TDistTreeMap::iterator,bool> it_in = treeMap.insert( make_pair( sqDist, tree ));
if ( !it_in.second ) // not unique distance to box center
treeMap.insert( it_in.first, make_pair( sqDist + 1e-13*treeMap.size(), tree ));
}
}
// find distance after which there is no sense to check tree's
double sqLimit = DBL_MAX;
TDistTreeMap::iterator sqDist_tree = treeMap.begin();
if ( treeMap.size() > 5 ) {
SMESH_OctreeNode* closestTree = sqDist_tree->second;
const Bnd_B3d& box = *closestTree->getBox();
double limit = sqrt( sqDist_tree->first ) + sqrt ( box.SquareExtent() );
sqLimit = limit * limit;
}
// get all nodes from trees
for ( ; sqDist_tree != treeMap.end(); ++sqDist_tree) {
if ( sqDist_tree->first > sqLimit )
break;
SMESH_OctreeNode* tree = sqDist_tree->second;
tree->NodesAround( tree->GetNodeIterator()->next(), &nodes );
}
}
// find closest among nodes
minSqDist = DBL_MAX;
const SMDS_MeshNode* closestNode = 0;
list<const SMDS_MeshNode*>::iterator nIt = nodes.begin();
for ( ; nIt != nodes.end(); ++nIt ) {
double sqDist = thePnt.SquareDistance( SMESH_TNodeXYZ( *nIt ) );
if ( minSqDist > sqDist ) {
closestNode = *nIt;
minSqDist = sqDist;
}
}
return closestNode;
}
//---------------------------------------------------------------------
/*!
* \brief Finds nodes located within a tolerance near a point
*/
int FindNearPoint(const gp_Pnt& point,
const double tolerance,
std::vector< const SMDS_MeshNode* >& foundNodes)
{
myOctreeNode->NodesAround( point.Coord(), foundNodes, tolerance );
return foundNodes.size();
}
//---------------------------------------------------------------------
/*!
* \brief Destructor
*/
~SMESH_NodeSearcherImpl() { delete myOctreeNode; }
//---------------------------------------------------------------------
/*!
* \brief Return the node tree
*/
const SMESH_OctreeNode* getTree() const { return myOctreeNode; }
private:
SMESH_OctreeNode* myOctreeNode;
SMDS_Mesh* myMesh;
double myHalfLeafSize; // max size of a leaf box
};
// ========================================================================
namespace // Utils used in SMESH_ElementSearcherImpl::FindElementsByPoint()
{
const int MaxNbElemsInLeaf = 10; // maximal number of elements in a leaf of tree
const int MaxLevel = 7; // maximal tree height -> nb terminal boxes: 8^7 = 2097152
const double NodeRadius = 1e-9; // to enlarge bnd box of element
//=======================================================================
/*!
* \brief Octal tree of bounding boxes of elements
*/
//=======================================================================
class ElementBndBoxTree : public SMESH_Octree
{
public:
ElementBndBoxTree(const SMDS_Mesh& mesh,
SMDSAbs_ElementType elemType,
SMDS_ElemIteratorPtr theElemIt = SMDS_ElemIteratorPtr(),
double tolerance = NodeRadius );
void getElementsNearPoint( const gp_Pnt& point, TIDSortedElemSet& foundElems );
void getElementsNearLine ( const gp_Ax1& line, TIDSortedElemSet& foundElems);
void getElementsInSphere ( const gp_XYZ& center,
const double radius, TIDSortedElemSet& foundElems);
size_t getSize() { return std::max( _size, _elements.size() ); }
virtual ~ElementBndBoxTree();
protected:
ElementBndBoxTree():_size(0) {}
SMESH_Octree* newChild() const { return new ElementBndBoxTree; }
void buildChildrenData();
Bnd_B3d* buildRootBox();
private:
//!< Bounding box of element
struct ElementBox : public Bnd_B3d
{
const SMDS_MeshElement* _element;
int _refCount; // an ElementBox can be included in several tree branches
ElementBox(const SMDS_MeshElement* elem, double tolerance);
};
vector< ElementBox* > _elements;
size_t _size;
};
//================================================================================
/*!
* \brief ElementBndBoxTree creation
*/
//================================================================================
ElementBndBoxTree::ElementBndBoxTree(const SMDS_Mesh& mesh, SMDSAbs_ElementType elemType, SMDS_ElemIteratorPtr theElemIt, double tolerance)
:SMESH_Octree( new SMESH_TreeLimit( MaxLevel, /*minSize=*/0. ))
{
int nbElems = mesh.GetMeshInfo().NbElements( elemType );
_elements.reserve( nbElems );
SMDS_ElemIteratorPtr elemIt = theElemIt ? theElemIt : mesh.elementsIterator( elemType );
while ( elemIt->more() )
_elements.push_back( new ElementBox( elemIt->next(),tolerance ));
compute();
}
//================================================================================
/*!
* \brief Destructor
*/
//================================================================================
ElementBndBoxTree::~ElementBndBoxTree()
{
for ( int i = 0; i < _elements.size(); ++i )
if ( --_elements[i]->_refCount <= 0 )
delete _elements[i];
}
//================================================================================
/*!
* \brief Return the maximal box
*/
//================================================================================
Bnd_B3d* ElementBndBoxTree::buildRootBox()
{
Bnd_B3d* box = new Bnd_B3d;
for ( int i = 0; i < _elements.size(); ++i )
box->Add( *_elements[i] );
return box;
}
//================================================================================
/*!
* \brief Redistrubute element boxes among children
*/
//================================================================================
void ElementBndBoxTree::buildChildrenData()
{
for ( int i = 0; i < _elements.size(); ++i )
{
for (int j = 0; j < 8; j++)
{
if ( !_elements[i]->IsOut( *myChildren[j]->getBox() ))
{
_elements[i]->_refCount++;
((ElementBndBoxTree*)myChildren[j])->_elements.push_back( _elements[i]);
}
}
_elements[i]->_refCount--;
}
_size = _elements.size();
SMESHUtils::FreeVector( _elements ); // = _elements.clear() + free memory
for (int j = 0; j < 8; j++)
{
ElementBndBoxTree* child = static_cast<ElementBndBoxTree*>( myChildren[j]);
if ( child->_elements.size() <= MaxNbElemsInLeaf )
child->myIsLeaf = true;
if ( child->_elements.capacity() - child->_elements.size() > 1000 )
SMESHUtils::CompactVector( child->_elements );
}
}
//================================================================================
/*!
* \brief Return elements which can include the point
*/
//================================================================================
void ElementBndBoxTree::getElementsNearPoint( const gp_Pnt& point,
TIDSortedElemSet& foundElems)
{
if ( getBox()->IsOut( point.XYZ() ))
return;
if ( isLeaf() )
{
for ( int i = 0; i < _elements.size(); ++i )
if ( !_elements[i]->IsOut( point.XYZ() ))
foundElems.insert( _elements[i]->_element );
}
else
{
for (int i = 0; i < 8; i++)
((ElementBndBoxTree*) myChildren[i])->getElementsNearPoint( point, foundElems );
}
}
//================================================================================
/*!
* \brief Return elements which can be intersected by the line
*/
//================================================================================
void ElementBndBoxTree::getElementsNearLine( const gp_Ax1& line,
TIDSortedElemSet& foundElems)
{
if ( getBox()->IsOut( line ))
return;
if ( isLeaf() )
{
for ( int i = 0; i < _elements.size(); ++i )
if ( !_elements[i]->IsOut( line ))
foundElems.insert( _elements[i]->_element );
}
else
{
for (int i = 0; i < 8; i++)
((ElementBndBoxTree*) myChildren[i])->getElementsNearLine( line, foundElems );
}
}
//================================================================================
/*!
* \brief Return elements from leaves intersecting the sphere
*/
//================================================================================
void ElementBndBoxTree::getElementsInSphere ( const gp_XYZ& center,
const double radius,
TIDSortedElemSet& foundElems)
{
if ( getBox()->IsOut( center, radius ))
return;
if ( isLeaf() )
{
for ( int i = 0; i < _elements.size(); ++i )
if ( !_elements[i]->IsOut( center, radius ))
foundElems.insert( _elements[i]->_element );
}
else
{
for (int i = 0; i < 8; i++)
((ElementBndBoxTree*) myChildren[i])->getElementsInSphere( center, radius, foundElems );
}
}
//================================================================================
/*!
* \brief Construct the element box
*/
//================================================================================
ElementBndBoxTree::ElementBox::ElementBox(const SMDS_MeshElement* elem, double tolerance)
{
_element = elem;
_refCount = 1;
SMDS_ElemIteratorPtr nIt = elem->nodesIterator();
while ( nIt->more() )
Add( SMESH_TNodeXYZ( nIt->next() ));
Enlarge( tolerance );
}
} // namespace
//=======================================================================
/*!
* \brief Implementation of search for the elements by point and
* of classification of point in 2D mesh
*/
//=======================================================================
SMESH_ElementSearcher::~SMESH_ElementSearcher()
{
}
struct SMESH_ElementSearcherImpl: public SMESH_ElementSearcher
{
SMDS_Mesh* _mesh;
SMDS_ElemIteratorPtr _meshPartIt;
ElementBndBoxTree* _ebbTree;
SMESH_NodeSearcherImpl* _nodeSearcher;
SMDSAbs_ElementType _elementType;
double _tolerance;
bool _outerFacesFound;
set<const SMDS_MeshElement*> _outerFaces; // empty means "no internal faces at all"
SMESH_ElementSearcherImpl( SMDS_Mesh& mesh, SMDS_ElemIteratorPtr elemIt=SMDS_ElemIteratorPtr())
: _mesh(&mesh),_meshPartIt(elemIt),_ebbTree(0),_nodeSearcher(0),_tolerance(-1),_outerFacesFound(false) {}
virtual ~SMESH_ElementSearcherImpl()
{
if ( _ebbTree ) delete _ebbTree; _ebbTree = 0;
if ( _nodeSearcher ) delete _nodeSearcher; _nodeSearcher = 0;
}
virtual int FindElementsByPoint(const gp_Pnt& point,
SMDSAbs_ElementType type,
vector< const SMDS_MeshElement* >& foundElements);
virtual TopAbs_State GetPointState(const gp_Pnt& point);
virtual const SMDS_MeshElement* FindClosestTo( const gp_Pnt& point,
SMDSAbs_ElementType type );
void GetElementsNearLine( const gp_Ax1& line,
SMDSAbs_ElementType type,
vector< const SMDS_MeshElement* >& foundElems);
double getTolerance();
bool getIntersParamOnLine(const gp_Lin& line, const SMDS_MeshElement* face,
const double tolerance, double & param);
void findOuterBoundary(const SMDS_MeshElement* anyOuterFace);
bool isOuterBoundary(const SMDS_MeshElement* face) const
{
return _outerFaces.empty() || _outerFaces.count(face);
}
struct TInters //!< data of intersection of the line and the mesh face (used in GetPointState())
{
const SMDS_MeshElement* _face;
gp_Vec _faceNorm;
bool _coincides; //!< the line lays in face plane
TInters(const SMDS_MeshElement* face, const gp_Vec& faceNorm, bool coinc=false)
: _face(face), _faceNorm( faceNorm ), _coincides( coinc ) {}
};
struct TFaceLink //!< link and faces sharing it (used in findOuterBoundary())
{
SMESH_TLink _link;
TIDSortedElemSet _faces;
TFaceLink( const SMDS_MeshNode* n1, const SMDS_MeshNode* n2, const SMDS_MeshElement* face)
: _link( n1, n2 ), _faces( &face, &face + 1) {}
};
};
ostream& operator<< (ostream& out, const SMESH_ElementSearcherImpl::TInters& i)
{
return out << "TInters(face=" << ( i._face ? i._face->GetID() : 0)
<< ", _coincides="<<i._coincides << ")";
}
//=======================================================================
/*!
* \brief define tolerance for search
*/
//=======================================================================
double SMESH_ElementSearcherImpl::getTolerance()
{
if ( _tolerance < 0 )
{
const SMDS_MeshInfo& meshInfo = _mesh->GetMeshInfo();
_tolerance = 0;
if ( _nodeSearcher && meshInfo.NbNodes() > 1 )
{
double boxSize = _nodeSearcher->getTree()->maxSize();
_tolerance = 1e-8 * boxSize/* / meshInfo.NbNodes()*/;
}
else if ( _ebbTree && meshInfo.NbElements() > 0 )
{
double boxSize = _ebbTree->maxSize();
_tolerance = 1e-8 * boxSize/* / meshInfo.NbElements()*/;
}
if ( _tolerance == 0 )
{
// define tolerance by size of a most complex element
int complexType = SMDSAbs_Volume;
while ( complexType > SMDSAbs_All &&
meshInfo.NbElements( SMDSAbs_ElementType( complexType )) < 1 )
--complexType;
if ( complexType == SMDSAbs_All ) return 0; // empty mesh
double elemSize;
if ( complexType == int( SMDSAbs_Node ))
{
SMDS_NodeIteratorPtr nodeIt = _mesh->nodesIterator();
elemSize = 1;
if ( meshInfo.NbNodes() > 2 )
elemSize = SMESH_TNodeXYZ( nodeIt->next() ).Distance( nodeIt->next() );
}
else
{
SMDS_ElemIteratorPtr elemIt =
_mesh->elementsIterator( SMDSAbs_ElementType( complexType ));
const SMDS_MeshElement* elem = elemIt->next();
SMDS_ElemIteratorPtr nodeIt = elem->nodesIterator();
SMESH_TNodeXYZ n1( nodeIt->next() );
elemSize = 0;
while ( nodeIt->more() )
{
double dist = n1.Distance( static_cast<const SMDS_MeshNode*>( nodeIt->next() ));
elemSize = max( dist, elemSize );
}
}
_tolerance = 1e-4 * elemSize;
}
}
return _tolerance;
}
//================================================================================
/*!
* \brief Find intersection of the line and an edge of face and return parameter on line
*/
//================================================================================
bool SMESH_ElementSearcherImpl::getIntersParamOnLine(const gp_Lin& line,
const SMDS_MeshElement* face,
const double tol,
double & param)
{
int nbInts = 0;
param = 0;
GeomAPI_ExtremaCurveCurve anExtCC;
Handle(Geom_Curve) lineCurve = new Geom_Line( line );
int nbNodes = face->IsQuadratic() ? face->NbNodes()/2 : face->NbNodes();
for ( int i = 0; i < nbNodes && nbInts < 2; ++i )
{
GC_MakeSegment edge( SMESH_TNodeXYZ( face->GetNode( i )),
SMESH_TNodeXYZ( face->GetNode( (i+1)%nbNodes) ));
anExtCC.Init( lineCurve, edge);
if ( anExtCC.NbExtrema() > 0 && anExtCC.LowerDistance() <= tol)
{
Quantity_Parameter pl, pe;
anExtCC.LowerDistanceParameters( pl, pe );
param += pl;
if ( ++nbInts == 2 )
break;
}
}
if ( nbInts > 0 ) param /= nbInts;
return nbInts > 0;
}
//================================================================================
/*!
* \brief Find all faces belonging to the outer boundary of mesh
*/
//================================================================================
void SMESH_ElementSearcherImpl::findOuterBoundary(const SMDS_MeshElement* outerFace)
{
if ( _outerFacesFound ) return;
// Collect all outer faces by passing from one outer face to another via their links
// and BTW find out if there are internal faces at all.
// checked links and links where outer boundary meets internal one
set< SMESH_TLink > visitedLinks, seamLinks;
// links to treat with already visited faces sharing them
list < TFaceLink > startLinks;
// load startLinks with the first outerFace
startLinks.push_back( TFaceLink( outerFace->GetNode(0), outerFace->GetNode(1), outerFace));
_outerFaces.insert( outerFace );
TIDSortedElemSet emptySet;
while ( !startLinks.empty() )
{
const SMESH_TLink& link = startLinks.front()._link;
TIDSortedElemSet& faces = startLinks.front()._faces;
outerFace = *faces.begin();
// find other faces sharing the link
const SMDS_MeshElement* f;
while (( f = SMESH_MeshAlgos::FindFaceInSet(link.node1(), link.node2(), emptySet, faces )))
faces.insert( f );
// select another outer face among the found
const SMDS_MeshElement* outerFace2 = 0;
if ( faces.size() == 2 )
{
outerFace2 = (outerFace == *faces.begin() ? *faces.rbegin() : *faces.begin());
}
else if ( faces.size() > 2 )
{
seamLinks.insert( link );
// link direction within the outerFace
gp_Vec n1n2( SMESH_TNodeXYZ( link.node1()),
SMESH_TNodeXYZ( link.node2()));
int i1 = outerFace->GetNodeIndex( link.node1() );
int i2 = outerFace->GetNodeIndex( link.node2() );
bool rev = ( abs(i2-i1) == 1 ? i1 > i2 : i2 > i1 );
if ( rev ) n1n2.Reverse();
// outerFace normal
gp_XYZ ofNorm, fNorm;
if ( SMESH_MeshAlgos::FaceNormal( outerFace, ofNorm, /*normalized=*/false ))
{
// direction from the link inside outerFace
gp_Vec dirInOF = gp_Vec( ofNorm ) ^ n1n2;
// sort all other faces by angle with the dirInOF
map< double, const SMDS_MeshElement* > angle2Face;
set< const SMDS_MeshElement*, TIDCompare >::const_iterator face = faces.begin();
for ( ; face != faces.end(); ++face )
{
if ( !SMESH_MeshAlgos::FaceNormal( *face, fNorm, /*normalized=*/false ))
continue;
gp_Vec dirInF = gp_Vec( fNorm ) ^ n1n2;
double angle = dirInOF.AngleWithRef( dirInF, n1n2 );
if ( angle < 0 ) angle += 2. * M_PI;
angle2Face.insert( make_pair( angle, *face ));
}
if ( !angle2Face.empty() )
outerFace2 = angle2Face.begin()->second;
}
}
// store the found outer face and add its links to continue seaching from
if ( outerFace2 )
{
_outerFaces.insert( outerFace );
int nbNodes = outerFace2->NbNodes()/( outerFace2->IsQuadratic() ? 2 : 1 );
for ( int i = 0; i < nbNodes; ++i )
{
SMESH_TLink link2( outerFace2->GetNode(i), outerFace2->GetNode((i+1)%nbNodes));
if ( visitedLinks.insert( link2 ).second )
startLinks.push_back( TFaceLink( link2.node1(), link2.node2(), outerFace2 ));
}
}
startLinks.pop_front();
}
_outerFacesFound = true;
if ( !seamLinks.empty() )
{
// There are internal boundaries touching the outher one,
// find all faces of internal boundaries in order to find
// faces of boundaries of holes, if any.
}
else
{
_outerFaces.clear();
}
}
//=======================================================================
/*!
* \brief Find elements of given type where the given point is IN or ON.
* Returns nb of found elements and elements them-selves.
*
* 'ALL' type means elements of any type excluding nodes, balls and 0D elements
*/
//=======================================================================
int SMESH_ElementSearcherImpl::
FindElementsByPoint(const gp_Pnt& point,
SMDSAbs_ElementType type,
vector< const SMDS_MeshElement* >& foundElements)
{
foundElements.clear();
double tolerance = getTolerance();
// =================================================================================
if ( type == SMDSAbs_Node || type == SMDSAbs_0DElement || type == SMDSAbs_Ball)
{
if ( !_nodeSearcher )
_nodeSearcher = new SMESH_NodeSearcherImpl( _mesh );
std::vector< const SMDS_MeshNode* > foundNodes;
_nodeSearcher->FindNearPoint( point, tolerance, foundNodes );
if ( type == SMDSAbs_Node )
{
foundElements.assign( foundNodes.begin(), foundNodes.end() );
}
else
{
for ( size_t i = 0; i < foundNodes.size(); ++i )
{
SMDS_ElemIteratorPtr elemIt = foundNodes[i]->GetInverseElementIterator( type );
while ( elemIt->more() )
foundElements.push_back( elemIt->next() );
}
}
}
// =================================================================================
else // elements more complex than 0D
{
if ( !_ebbTree || _elementType != type )
{
if ( _ebbTree ) delete _ebbTree;
_ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt, tolerance );
}
TIDSortedElemSet suspectElems;
_ebbTree->getElementsNearPoint( point, suspectElems );
TIDSortedElemSet::iterator elem = suspectElems.begin();
for ( ; elem != suspectElems.end(); ++elem )
if ( !SMESH_MeshAlgos::IsOut( *elem, point, tolerance ))
foundElements.push_back( *elem );
}
return foundElements.size();
}
//=======================================================================
/*!
* \brief Find an element of given type most close to the given point
*
* WARNING: Only face search is implemeneted so far
*/
//=======================================================================
const SMDS_MeshElement*
SMESH_ElementSearcherImpl::FindClosestTo( const gp_Pnt& point,
SMDSAbs_ElementType type )
{
const SMDS_MeshElement* closestElem = 0;
if ( type == SMDSAbs_Face || type == SMDSAbs_Volume )
{
if ( !_ebbTree || _elementType != type )
{
if ( _ebbTree ) delete _ebbTree;
_ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt );
}
TIDSortedElemSet suspectElems;
_ebbTree->getElementsNearPoint( point, suspectElems );
if ( suspectElems.empty() && _ebbTree->maxSize() > 0 )
{
gp_Pnt boxCenter = 0.5 * ( _ebbTree->getBox()->CornerMin() +
_ebbTree->getBox()->CornerMax() );
double radius = -1;
if ( _ebbTree->getBox()->IsOut( point.XYZ() ))
radius = point.Distance( boxCenter ) - 0.5 * _ebbTree->maxSize();
if ( radius < 0 )
radius = _ebbTree->maxSize() / pow( 2., _ebbTree->getHeight()) / 2;
while ( suspectElems.empty() )
{
_ebbTree->getElementsInSphere( point.XYZ(), radius, suspectElems );
radius *= 1.1;
}
}
double minDist = std::numeric_limits<double>::max();
multimap< double, const SMDS_MeshElement* > dist2face;
TIDSortedElemSet::iterator elem = suspectElems.begin();
for ( ; elem != suspectElems.end(); ++elem )
{
double dist = SMESH_MeshAlgos::GetDistance( *elem, point );
if ( dist < minDist + 1e-10)
{
minDist = dist;
dist2face.insert( dist2face.begin(), make_pair( dist, *elem ));
}
}
if ( !dist2face.empty() )
{
multimap< double, const SMDS_MeshElement* >::iterator d2f = dist2face.begin();
closestElem = d2f->second;
// if there are several elements at the same distance, select one
// with GC closest to the point
typedef SMDS_StdIterator< SMESH_TNodeXYZ, SMDS_ElemIteratorPtr > TXyzIterator;
double minDistToGC = 0;
for ( ++d2f; d2f != dist2face.end() && fabs( d2f->first - minDist ) < 1e-10; ++d2f )
{
if ( minDistToGC == 0 )
{
gp_XYZ gc(0,0,0);
gc = accumulate( TXyzIterator(closestElem->nodesIterator()),
TXyzIterator(), gc ) / closestElem->NbNodes();
minDistToGC = point.SquareDistance( gc );
}
gp_XYZ gc(0,0,0);
gc = accumulate( TXyzIterator( d2f->second->nodesIterator()),
TXyzIterator(), gc ) / d2f->second->NbNodes();
double d = point.SquareDistance( gc );
if ( d < minDistToGC )
{
minDistToGC = d;
closestElem = d2f->second;
}
}
// cout << "FindClosestTo( " <<point.X()<<", "<<point.Y()<<", "<<point.Z()<<" ) FACE "
// <<closestElem->GetID() << " DIST " << minDist << endl;
}
}
else
{
// NOT IMPLEMENTED SO FAR
}
return closestElem;
}
//================================================================================
/*!
* \brief Classify the given point in the closed 2D mesh
*/
//================================================================================
TopAbs_State SMESH_ElementSearcherImpl::GetPointState(const gp_Pnt& point)
{
double tolerance = getTolerance();
if ( !_ebbTree || _elementType != SMDSAbs_Face )
{
if ( _ebbTree ) delete _ebbTree;
_ebbTree = new ElementBndBoxTree( *_mesh, _elementType = SMDSAbs_Face, _meshPartIt );
}
// Algo: analyse transition of a line starting at the point through mesh boundary;
// try three lines parallel to axis of the coordinate system and perform rough
// analysis. If solution is not clear perform thorough analysis.
const int nbAxes = 3;
gp_Dir axisDir[ nbAxes ] = { gp::DX(), gp::DY(), gp::DZ() };
map< double, TInters > paramOnLine2TInters[ nbAxes ];
list< TInters > tangentInters[ nbAxes ]; // of faces whose plane includes the line
multimap< int, int > nbInt2Axis; // to find the simplest case
for ( int axis = 0; axis < nbAxes; ++axis )
{
gp_Ax1 lineAxis( point, axisDir[axis]);
gp_Lin line ( lineAxis );
TIDSortedElemSet suspectFaces; // faces possibly intersecting the line
_ebbTree->getElementsNearLine( lineAxis, suspectFaces );
// Intersect faces with the line
map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
TIDSortedElemSet::iterator face = suspectFaces.begin();
for ( ; face != suspectFaces.end(); ++face )
{
// get face plane
gp_XYZ fNorm;
if ( !SMESH_MeshAlgos::FaceNormal( *face, fNorm, /*normalized=*/false)) continue;
gp_Pln facePlane( SMESH_TNodeXYZ( (*face)->GetNode(0)), fNorm );
// perform intersection
IntAna_IntConicQuad intersection( line, IntAna_Quadric( facePlane ));
if ( !intersection.IsDone() )
continue;
if ( intersection.IsInQuadric() )
{
tangentInters[ axis ].push_back( TInters( *face, fNorm, true ));
}
else if ( ! intersection.IsParallel() && intersection.NbPoints() > 0 )
{
gp_Pnt intersectionPoint = intersection.Point(1);
if ( !SMESH_MeshAlgos::IsOut( *face, intersectionPoint, tolerance ))
u2inters.insert(make_pair( intersection.ParamOnConic(1), TInters( *face, fNorm )));
}
}
// Analyse intersections roughly
int nbInter = u2inters.size();
if ( nbInter == 0 )
return TopAbs_OUT;
double f = u2inters.begin()->first, l = u2inters.rbegin()->first;
if ( nbInter == 1 ) // not closed mesh
return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
return TopAbs_ON;
if ( (f<0) == (l<0) )
return TopAbs_OUT;
int nbIntBeforePoint = std::distance( u2inters.begin(), u2inters.lower_bound(0));
int nbIntAfterPoint = nbInter - nbIntBeforePoint;
if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
return TopAbs_IN;
nbInt2Axis.insert( make_pair( min( nbIntBeforePoint, nbIntAfterPoint ), axis ));
if ( _outerFacesFound ) break; // pass to thorough analysis
} // three attempts - loop on CS axes
// Analyse intersections thoroughly.
// We make two loops maximum, on the first one we only exclude touching intersections,
// on the second, if situation is still unclear, we gather and use information on
// position of faces (internal or outer). If faces position is already gathered,
// we make the second loop right away.
for ( int hasPositionInfo = _outerFacesFound; hasPositionInfo < 2; ++hasPositionInfo )
{
multimap< int, int >::const_iterator nb_axis = nbInt2Axis.begin();
for ( ; nb_axis != nbInt2Axis.end(); ++nb_axis )
{
int axis = nb_axis->second;
map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
gp_Ax1 lineAxis( point, axisDir[axis]);
gp_Lin line ( lineAxis );
// add tangent intersections to u2inters
double param;
list< TInters >::const_iterator tgtInt = tangentInters[ axis ].begin();
for ( ; tgtInt != tangentInters[ axis ].end(); ++tgtInt )
if ( getIntersParamOnLine( line, tgtInt->_face, tolerance, param ))
u2inters.insert(make_pair( param, *tgtInt ));
tangentInters[ axis ].clear();
// Count intersections before and after the point excluding touching ones.
// If hasPositionInfo we count intersections of outer boundary only
int nbIntBeforePoint = 0, nbIntAfterPoint = 0;
double f = numeric_limits<double>::max(), l = -numeric_limits<double>::max();
map< double, TInters >::iterator u_int1 = u2inters.begin(), u_int2 = u_int1;
bool ok = ! u_int1->second._coincides;
while ( ok && u_int1 != u2inters.end() )
{
double u = u_int1->first;
bool touchingInt = false;
if ( ++u_int2 != u2inters.end() )
{
// skip intersections at the same point (if the line passes through edge or node)
int nbSamePnt = 0;
while ( u_int2 != u2inters.end() && fabs( u_int2->first - u ) < tolerance )
{
++nbSamePnt;
++u_int2;
}
// skip tangent intersections
int nbTgt = 0;
const SMDS_MeshElement* prevFace = u_int1->second._face;
while ( ok && u_int2->second._coincides )
{
if ( SMESH_MeshAlgos::GetCommonNodes(prevFace , u_int2->second._face).empty() )
ok = false;
else
{
nbTgt++;
u_int2++;
ok = ( u_int2 != u2inters.end() );
}
}
if ( !ok ) break;
// skip intersections at the same point after tangent intersections
if ( nbTgt > 0 )
{
double u2 = u_int2->first;
++u_int2;
while ( u_int2 != u2inters.end() && fabs( u_int2->first - u2 ) < tolerance )
{
++nbSamePnt;
++u_int2;
}
}
// decide if we skipped a touching intersection
if ( nbSamePnt + nbTgt > 0 )
{
double minDot = numeric_limits<double>::max(), maxDot = -numeric_limits<double>::max();
map< double, TInters >::iterator u_int = u_int1;
for ( ; u_int != u_int2; ++u_int )
{
if ( u_int->second._coincides ) continue;
double dot = u_int->second._faceNorm * line.Direction();
if ( dot > maxDot ) maxDot = dot;
if ( dot < minDot ) minDot = dot;
}
touchingInt = ( minDot*maxDot < 0 );
}
}
if ( !touchingInt )
{
if ( !hasPositionInfo || isOuterBoundary( u_int1->second._face ))
{
if ( u < 0 )
++nbIntBeforePoint;
else
++nbIntAfterPoint;
}
if ( u < f ) f = u;
if ( u > l ) l = u;
}
u_int1 = u_int2; // to next intersection
} // loop on intersections with one line
if ( ok )
{
if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
return TopAbs_ON;
if ( nbIntBeforePoint == 0 || nbIntAfterPoint == 0)
return TopAbs_OUT;
if ( nbIntBeforePoint + nbIntAfterPoint == 1 ) // not closed mesh
return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
return TopAbs_IN;
if ( (f<0) == (l<0) )
return TopAbs_OUT;
if ( hasPositionInfo )
return nbIntBeforePoint % 2 ? TopAbs_IN : TopAbs_OUT;
}
} // loop on intersections of the tree lines - thorough analysis
if ( !hasPositionInfo )
{
// gather info on faces position - is face in the outer boundary or not
map< double, TInters > & u2inters = paramOnLine2TInters[ 0 ];
findOuterBoundary( u2inters.begin()->second._face );
}
} // two attempts - with and w/o faces position info in the mesh
return TopAbs_UNKNOWN;
}
//=======================================================================
/*!
* \brief Return elements possibly intersecting the line
*/
//=======================================================================
void SMESH_ElementSearcherImpl::GetElementsNearLine( const gp_Ax1& line,
SMDSAbs_ElementType type,
vector< const SMDS_MeshElement* >& foundElems)
{
if ( !_ebbTree || _elementType != type )
{
if ( _ebbTree ) delete _ebbTree;
_ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt );
}
TIDSortedElemSet suspectFaces; // elements possibly intersecting the line
_ebbTree->getElementsNearLine( line, suspectFaces );
foundElems.assign( suspectFaces.begin(), suspectFaces.end());
}
//=======================================================================
/*!
* \brief Return true if the point is IN or ON of the element
*/
//=======================================================================
bool SMESH_MeshAlgos::IsOut( const SMDS_MeshElement* element, const gp_Pnt& point, double tol )
{
if ( element->GetType() == SMDSAbs_Volume)
{
return SMDS_VolumeTool( element ).IsOut( point.X(), point.Y(), point.Z(), tol );
}
// get ordered nodes
vector< gp_XYZ > xyz;
vector<const SMDS_MeshNode*> nodeList;
SMDS_ElemIteratorPtr nodeIt = element->nodesIterator();
if ( element->IsQuadratic() ) {
nodeIt = element->interlacedNodesElemIterator();
// if (const SMDS_VtkFace* f=dynamic_cast<const SMDS_VtkFace*>(element))
// nodeIt = f->interlacedNodesElemIterator();
// else if (const SMDS_VtkEdge* e =dynamic_cast<const SMDS_VtkEdge*>(element))
// nodeIt = e->interlacedNodesElemIterator();
}
while ( nodeIt->more() )
{
SMESH_TNodeXYZ node = nodeIt->next();
xyz.push_back( node );
nodeList.push_back(node._node);
}
int i, nbNodes = (int) nodeList.size(); // central node of biquadratic is missing
if ( element->GetType() == SMDSAbs_Face ) // --------------------------------------------------
{
// compute face normal
gp_Vec faceNorm(0,0,0);
xyz.push_back( xyz.front() );
nodeList.push_back( nodeList.front() );
for ( i = 0; i < nbNodes; ++i )
{
gp_Vec edge1( xyz[i+1], xyz[i]);
gp_Vec edge2( xyz[i+1], xyz[(i+2)%nbNodes] );
faceNorm += edge1 ^ edge2;
}
double normSize = faceNorm.Magnitude();
if ( normSize <= tol )
{
// degenerated face: point is out if it is out of all face edges
for ( i = 0; i < nbNodes; ++i )
{
SMDS_LinearEdge edge( nodeList[i], nodeList[i+1] );
if ( !IsOut( &edge, point, tol ))
return false;
}
return true;
}
faceNorm /= normSize;
// check if the point lays on face plane
gp_Vec n2p( xyz[0], point );
if ( fabs( n2p * faceNorm ) > tol )
return true; // not on face plane
// check if point is out of face boundary:
// define it by closest transition of a ray point->infinity through face boundary
// on the face plane.
// First, find normal of a plane perpendicular to face plane, to be used as a cutting tool
// to find intersections of the ray with the boundary.
gp_Vec ray = n2p;
gp_Vec plnNorm = ray ^ faceNorm;
normSize = plnNorm.Magnitude();
if ( normSize <= tol ) return false; // point coincides with the first node
plnNorm /= normSize;
// for each node of the face, compute its signed distance to the plane
vector<double> dist( nbNodes + 1);
for ( i = 0; i < nbNodes; ++i )
{
gp_Vec n2p( xyz[i], point );
dist[i] = n2p * plnNorm;
}
dist.back() = dist.front();
// find the closest intersection
int iClosest = -1;
double rClosest, distClosest = 1e100;;
gp_Pnt pClosest;
for ( i = 0; i < nbNodes; ++i )
{
double r;
if ( fabs( dist[i]) < tol )
r = 0.;
else if ( fabs( dist[i+1]) < tol )
r = 1.;
else if ( dist[i] * dist[i+1] < 0 )
r = dist[i] / ( dist[i] - dist[i+1] );
else
continue; // no intersection
gp_Pnt pInt = xyz[i] * (1.-r) + xyz[i+1] * r;
gp_Vec p2int ( point, pInt);
if ( p2int * ray > -tol ) // right half-space
{
double intDist = p2int.SquareMagnitude();
if ( intDist < distClosest )
{
iClosest = i;
rClosest = r;
pClosest = pInt;
distClosest = intDist;
}
}
}
if ( iClosest < 0 )
return true; // no intesections - out
// analyse transition
gp_Vec edge( xyz[iClosest], xyz[iClosest+1] );
gp_Vec edgeNorm = -( edge ^ faceNorm ); // normal to intersected edge pointing out of face
gp_Vec p2int ( point, pClosest );
bool out = (edgeNorm * p2int) < -tol;
if ( rClosest > 0. && rClosest < 1. ) // not node intersection
return out;
// ray pass through a face node; analyze transition through an adjacent edge
gp_Pnt p1 = xyz[ (rClosest == 0.) ? ((iClosest+nbNodes-1) % nbNodes) : (iClosest+1) ];
gp_Pnt p2 = xyz[ (rClosest == 0.) ? iClosest : ((iClosest+2) % nbNodes) ];
gp_Vec edgeAdjacent( p1, p2 );
gp_Vec edgeNorm2 = -( edgeAdjacent ^ faceNorm );
bool out2 = (edgeNorm2 * p2int) < -tol;
bool covexCorner = ( edgeNorm * edgeAdjacent * (rClosest==1. ? 1. : -1.)) < 0;
return covexCorner ? (out || out2) : (out && out2);
}
if ( element->GetType() == SMDSAbs_Edge ) // --------------------------------------------------
{
// point is out of edge if it is NOT ON any straight part of edge
// (we consider quadratic edge as being composed of two straight parts)
for ( i = 1; i < nbNodes; ++i )
{
gp_Vec edge( xyz[i-1], xyz[i]);
gp_Vec n1p ( xyz[i-1], point);
double dist = ( edge ^ n1p ).Magnitude() / edge.Magnitude();
if ( dist > tol )
continue;
gp_Vec n2p( xyz[i], point );
if ( fabs( edge.Magnitude() - n1p.Magnitude() - n2p.Magnitude()) > tol )
continue;
return false; // point is ON this part
}
return true;
}
// Node or 0D element -------------------------------------------------------------------------
{
gp_Vec n2p ( xyz[0], point );
return n2p.Magnitude() <= tol;
}
return true;
}
//=======================================================================
namespace
{
// Position of a point relative to a segment
// . .
// . LEFT .
// . .
// VERTEX 1 o----ON-----> VERTEX 2
// . .
// . RIGHT .
// . .
enum PositionName { POS_LEFT = 1, POS_VERTEX = 2, POS_RIGHT = 4, //POS_ON = 8,
POS_ALL = POS_LEFT | POS_RIGHT | POS_VERTEX };
struct PointPos
{
PositionName _name;
int _index; // index of vertex or segment
PointPos( PositionName n, int i=-1 ): _name(n), _index(i) {}
bool operator < (const PointPos& other ) const
{
if ( _name == other._name )
return ( _index < 0 || other._index < 0 ) ? false : _index < other._index;
return _name < other._name;
}
};
//================================================================================
/*!
* \brief Return of a point relative to a segment
* \param point2D - the point to analyze position of
* \param xyVec - end points of segments
* \param index0 - 0-based index of the first point of segment
* \param posToFindOut - flags of positions to detect
* \retval PointPos - point position
*/
//================================================================================
PointPos getPointPosition( const gp_XY& point2D,
const gp_XY* segEnds,
const int index0 = 0,
const int posToFindOut = POS_ALL)
{
const gp_XY& p1 = segEnds[ index0 ];
const gp_XY& p2 = segEnds[ index0+1 ];
const gp_XY grad = p2 - p1;
if ( posToFindOut & POS_VERTEX )
{
// check if the point2D is at "vertex 1" zone
gp_XY pp1[2] = { p1, gp_XY( p1.X() - grad.Y(),
p1.Y() + grad.X() ) };
if ( getPointPosition( point2D, pp1, 0, POS_LEFT|POS_RIGHT )._name == POS_LEFT )
return PointPos( POS_VERTEX, index0 );
// check if the point2D is at "vertex 2" zone
gp_XY pp2[2] = { p2, gp_XY( p2.X() - grad.Y(),
p2.Y() + grad.X() ) };
if ( getPointPosition( point2D, pp2, 0, POS_LEFT|POS_RIGHT )._name == POS_RIGHT )
return PointPos( POS_VERTEX, index0 + 1);
}
double edgeEquation =
( point2D.X() - p1.X() ) * grad.Y() - ( point2D.Y() - p1.Y() ) * grad.X();
return PointPos( edgeEquation < 0 ? POS_LEFT : POS_RIGHT, index0 );
}
}
//=======================================================================
/*!
* \brief Return minimal distance from a point to an element
*
* Currently we ignore non-planarity and 2nd order of face
*/
//=======================================================================
double SMESH_MeshAlgos::GetDistance( const SMDS_MeshElement* elem,
const gp_Pnt& point )
{
switch ( elem->GetType() )
{
case SMDSAbs_Volume:
return GetDistance( dynamic_cast<const SMDS_MeshVolume*>( elem ), point);
case SMDSAbs_Face:
return GetDistance( dynamic_cast<const SMDS_MeshFace*>( elem ), point);
case SMDSAbs_Edge:
return GetDistance( dynamic_cast<const SMDS_MeshEdge*>( elem ), point);
case SMDSAbs_Node:
return point.Distance( SMESH_TNodeXYZ( elem ));
}
return -1;
}
//=======================================================================
/*!
* \brief Return minimal distance from a point to a face
*
* Currently we ignore non-planarity and 2nd order of face
*/
//=======================================================================
double SMESH_MeshAlgos::GetDistance( const SMDS_MeshFace* face,
const gp_Pnt& point )
{
double badDistance = -1;
if ( !face ) return badDistance;
// coordinates of nodes (medium nodes, if any, ignored)
typedef SMDS_StdIterator< SMESH_TNodeXYZ, SMDS_ElemIteratorPtr > TXyzIterator;
vector<gp_XYZ> xyz( TXyzIterator( face->nodesIterator()), TXyzIterator() );
xyz.resize( face->NbCornerNodes()+1 );
// transformation to get xyz[0] lies on the origin, xyz[1] lies on the Z axis,
// and xyz[2] lies in the XZ plane. This is to pass to 2D space on XZ plane.
gp_Trsf trsf;
gp_Vec OZ ( xyz[0], xyz[1] );
gp_Vec OX ( xyz[0], xyz[2] );
if ( OZ.Magnitude() < std::numeric_limits<double>::min() )
{
if ( xyz.size() < 4 ) return badDistance;
OZ = gp_Vec ( xyz[0], xyz[2] );
OX = gp_Vec ( xyz[0], xyz[3] );
}
gp_Ax3 tgtCS;
try {
tgtCS = gp_Ax3( xyz[0], OZ, OX );
}
catch ( Standard_Failure ) {
return badDistance;
}
trsf.SetTransformation( tgtCS );
// move all the nodes to 2D
vector<gp_XY> xy( xyz.size() );
for ( size_t i = 0;i < xyz.size()-1; ++i )
{
gp_XYZ p3d = xyz[i];
trsf.Transforms( p3d );
xy[i].SetCoord( p3d.X(), p3d.Z() );
}
xyz.back() = xyz.front();
xy.back() = xy.front();
// // move the point in 2D
gp_XYZ tmpPnt = point.XYZ();
trsf.Transforms( tmpPnt );
gp_XY point2D( tmpPnt.X(), tmpPnt.Z() );
// loop on segments of the face to analyze point position ralative to the face
set< PointPos > pntPosSet;
for ( size_t i = 1; i < xy.size(); ++i )
{
PointPos pos = getPointPosition( point2D, &xy[0], i-1 );
pntPosSet.insert( pos );
}
// compute distance
PointPos pos = *pntPosSet.begin();
// cout << "Face " << face->GetID() << " DIST: ";
switch ( pos._name )
{
case POS_LEFT: {
// point is most close to a segment
gp_Vec p0p1( point, xyz[ pos._index ] );
gp_Vec p1p2( xyz[ pos._index ], xyz[ pos._index+1 ]); // segment vector
p1p2.Normalize();
double projDist = p0p1 * p1p2; // distance projected to the segment
gp_Vec projVec = p1p2 * projDist;
gp_Vec distVec = p0p1 - projVec;
// cout << distVec.Magnitude() << ", SEG " << face->GetNode(pos._index)->GetID()
// << " - " << face->GetNodeWrap(pos._index+1)->GetID() << endl;
return distVec.Magnitude();
}
case POS_RIGHT: {
// point is inside the face
double distToFacePlane = tmpPnt.Y();
// cout << distToFacePlane << ", INSIDE " << endl;
return Abs( distToFacePlane );
}
case POS_VERTEX: {
// point is most close to a node
gp_Vec distVec( point, xyz[ pos._index ]);
// cout << distVec.Magnitude() << " VERTEX " << face->GetNode(pos._index)->GetID() << endl;
return distVec.Magnitude();
}
}
return badDistance;
}
//=======================================================================
/*!
* \brief Return minimal distance from a point to an edge
*/
//=======================================================================
double SMESH_MeshAlgos::GetDistance( const SMDS_MeshEdge* edge, const gp_Pnt& point )
{
throw SALOME_Exception(LOCALIZED("not implemented so far"));
}
//=======================================================================
/*!
* \brief Return minimal distance from a point to a volume
*
* Currently we ignore non-planarity and 2nd order
*/
//=======================================================================
double SMESH_MeshAlgos::GetDistance( const SMDS_MeshVolume* volume, const gp_Pnt& point )
{
SMDS_VolumeTool vTool( volume );
vTool.SetExternalNormal();
const int iQ = volume->IsQuadratic() ? 2 : 1;
double n[3], bc[3];
double minDist = 1e100, dist;
for ( int iF = 0; iF < vTool.NbFaces(); ++iF )
{
// skip a facet with normal not "looking at" the point
if ( !vTool.GetFaceNormal( iF, n[0], n[1], n[2] ) ||
!vTool.GetFaceBaryCenter( iF, bc[0], bc[1], bc[2] ))
continue;
gp_XYZ bcp = point.XYZ() - gp_XYZ( bc[0], bc[1], bc[2] );
if ( gp_XYZ( n[0], n[1], n[2] ) * bcp < 1e-6 )
continue;
// find distance to a facet
const SMDS_MeshNode** nodes = vTool.GetFaceNodes( iF );
switch ( vTool.NbFaceNodes( iF ) / iQ ) {
case 3:
{
SMDS_FaceOfNodes tmpFace( nodes[0], nodes[ 1*iQ ], nodes[ 2*iQ ] );
dist = GetDistance( &tmpFace, point );
break;
}
case 4:
{
SMDS_FaceOfNodes tmpFace( nodes[0], nodes[ 1*iQ ], nodes[ 2*iQ ], nodes[ 3*iQ ]);
dist = GetDistance( &tmpFace, point );
break;
}
default:
vector<const SMDS_MeshNode *> nvec( nodes, nodes + vTool.NbFaceNodes( iF ));
SMDS_PolygonalFaceOfNodes tmpFace( nvec );
dist = GetDistance( &tmpFace, point );
}
minDist = Min( minDist, dist );
}
return minDist;
}
//================================================================================
/*!
* \brief Returns barycentric coordinates of a point within a triangle.
* A not returned bc2 = 1. - bc0 - bc1.
* The point lies within the triangle if ( bc0 >= 0 && bc1 >= 0 && bc0+bc1 <= 1 )
*/
//================================================================================
void SMESH_MeshAlgos::GetBarycentricCoords( const gp_XY& p,
const gp_XY& t0,
const gp_XY& t1,
const gp_XY& t2,
double & bc0,
double & bc1)
{
const double // matrix 2x2
T11 = t0.X()-t2.X(), T12 = t1.X()-t2.X(),
T21 = t0.Y()-t2.Y(), T22 = t1.Y()-t2.Y();
const double Tdet = T11*T22 - T12*T21; // matrix determinant
if ( Abs( Tdet ) < std::numeric_limits<double>::min() )
{
bc0 = bc1 = 2.;
return;
}
// matrix inverse
const double t11 = T22, t12 = -T12, t21 = -T21, t22 = T11;
// vector
const double r11 = p.X()-t2.X(), r12 = p.Y()-t2.Y();
// barycentric coordinates: mutiply matrix by vector
bc0 = (t11 * r11 + t12 * r12)/Tdet;
bc1 = (t21 * r11 + t22 * r12)/Tdet;
}
//=======================================================================
//function : FindFaceInSet
//purpose : Return a face having linked nodes n1 and n2 and which is
// - not in avoidSet,
// - in elemSet provided that !elemSet.empty()
// i1 and i2 optionally returns indices of n1 and n2
//=======================================================================
const SMDS_MeshElement*
SMESH_MeshAlgos::FindFaceInSet(const SMDS_MeshNode* n1,
const SMDS_MeshNode* n2,
const TIDSortedElemSet& elemSet,
const TIDSortedElemSet& avoidSet,
int* n1ind,
int* n2ind)
{
int i1, i2;
const SMDS_MeshElement* face = 0;
SMDS_ElemIteratorPtr invElemIt = n1->GetInverseElementIterator(SMDSAbs_Face);
//MESSAGE("n1->GetInverseElementIterator(SMDSAbs_Face) " << invElemIt);
while ( invElemIt->more() && !face ) // loop on inverse faces of n1
{
//MESSAGE("in while ( invElemIt->more() && !face )");
const SMDS_MeshElement* elem = invElemIt->next();
if (avoidSet.count( elem ))
continue;
if ( !elemSet.empty() && !elemSet.count( elem ))
continue;
// index of n1
i1 = elem->GetNodeIndex( n1 );
// find a n2 linked to n1
int nbN = elem->IsQuadratic() ? elem->NbNodes()/2 : elem->NbNodes();
for ( int di = -1; di < 2 && !face; di += 2 )
{
i2 = (i1+di+nbN) % nbN;
if ( elem->GetNode( i2 ) == n2 )
face = elem;
}
if ( !face && elem->IsQuadratic())
{
// analysis for quadratic elements using all nodes
// const SMDS_VtkFace* F = dynamic_cast<const SMDS_VtkFace*>(elem);
// if (!F) throw SALOME_Exception(LOCALIZED("not an SMDS_VtkFace"));
// use special nodes iterator
SMDS_ElemIteratorPtr anIter = elem->interlacedNodesElemIterator();
const SMDS_MeshNode* prevN = static_cast<const SMDS_MeshNode*>( anIter->next() );
for ( i1 = -1, i2 = 0; anIter->more() && !face; i1++, i2++ )
{
const SMDS_MeshNode* n = static_cast<const SMDS_MeshNode*>( anIter->next() );
if ( n1 == prevN && n2 == n )
{
face = elem;
}
else if ( n2 == prevN && n1 == n )
{
face = elem; swap( i1, i2 );
}
prevN = n;
}
}
}
if ( n1ind ) *n1ind = i1;
if ( n2ind ) *n2ind = i2;
return face;
}
//================================================================================
/*!
* \brief Calculate normal of a mesh face
*/
//================================================================================
bool SMESH_MeshAlgos::FaceNormal(const SMDS_MeshElement* F, gp_XYZ& normal, bool normalized)
{
if ( !F || F->GetType() != SMDSAbs_Face )
return false;
normal.SetCoord(0,0,0);
int nbNodes = F->IsQuadratic() ? F->NbNodes()/2 : F->NbNodes();
for ( int i = 0; i < nbNodes-2; ++i )
{
gp_XYZ p[3];
for ( int n = 0; n < 3; ++n )
{
const SMDS_MeshNode* node = F->GetNode( i + n );
p[n].SetCoord( node->X(), node->Y(), node->Z() );
}
normal += ( p[2] - p[1] ) ^ ( p[0] - p[1] );
}
double size2 = normal.SquareModulus();
bool ok = ( size2 > numeric_limits<double>::min() * numeric_limits<double>::min());
if ( normalized && ok )
normal /= sqrt( size2 );
return ok;
}
//=======================================================================
//function : GetCommonNodes
//purpose : Return nodes common to two elements
//=======================================================================
vector< const SMDS_MeshNode*> SMESH_MeshAlgos::GetCommonNodes(const SMDS_MeshElement* e1,
const SMDS_MeshElement* e2)
{
vector< const SMDS_MeshNode*> common;
for ( int i = 0 ; i < e1->NbNodes(); ++i )
if ( e2->GetNodeIndex( e1->GetNode( i )) >= 0 )
common.push_back( e1->GetNode( i ));
return common;
}
//=======================================================================
/*!
* \brief Return SMESH_NodeSearcher
*/
//=======================================================================
SMESH_NodeSearcher* SMESH_MeshAlgos::GetNodeSearcher(SMDS_Mesh& mesh)
{
return new SMESH_NodeSearcherImpl( &mesh );
}
//=======================================================================
/*!
* \brief Return SMESH_ElementSearcher
*/
//=======================================================================
SMESH_ElementSearcher* SMESH_MeshAlgos::GetElementSearcher(SMDS_Mesh& mesh)
{
return new SMESH_ElementSearcherImpl( mesh );
}
//=======================================================================
/*!
* \brief Return SMESH_ElementSearcher acting on a sub-set of elements
*/
//=======================================================================
SMESH_ElementSearcher* SMESH_MeshAlgos::GetElementSearcher(SMDS_Mesh& mesh,
SMDS_ElemIteratorPtr elemIt)
{
return new SMESH_ElementSearcherImpl( mesh, elemIt );
}