1 // Copyright (C) 2007-2016 CEA/DEN, EDF R&D, OPEN CASCADE
3 // Copyright (C) 2003-2007 OPEN CASCADE, EADS/CCR, LIP6, CEA/DEN,
4 // CEDRAT, EDF R&D, LEG, PRINCIPIA R&D, BUREAU VERITAS
6 // This library is free software; you can redistribute it and/or
7 // modify it under the terms of the GNU Lesser General Public
8 // License as published by the Free Software Foundation; either
9 // version 2.1 of the License, or (at your option) any later version.
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 // Lesser General Public License for more details.
16 // You should have received a copy of the GNU Lesser General Public
17 // License along with this library; if not, write to the Free Software
18 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 // See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
22 // File : SMESH_MeshAlgos.hxx
23 // Created : Tue Apr 30 18:00:36 2013
24 // Author : Edward AGAPOV (eap)
26 // This file holds some low level algorithms extracted from SMESH_MeshEditor
27 // to make them accessible from Controls package
29 #include "SMESH_MeshAlgos.hxx"
31 #include "SMDS_FaceOfNodes.hxx"
32 #include "SMDS_LinearEdge.hxx"
33 #include "SMDS_Mesh.hxx"
34 #include "SMDS_PolygonalFaceOfNodes.hxx"
35 #include "SMDS_VolumeTool.hxx"
36 #include "SMESH_OctreeNode.hxx"
38 #include <GC_MakeSegment.hxx>
39 #include <GeomAPI_ExtremaCurveCurve.hxx>
40 #include <Geom_Line.hxx>
41 #include <IntAna_IntConicQuad.hxx>
42 #include <IntAna_Quadric.hxx>
51 //=======================================================================
53 * \brief Implementation of search for the node closest to point
55 //=======================================================================
57 struct SMESH_NodeSearcherImpl: public SMESH_NodeSearcher
59 //---------------------------------------------------------------------
63 SMESH_NodeSearcherImpl( const SMDS_Mesh* theMesh = 0,
64 SMDS_ElemIteratorPtr theElemIt = SMDS_ElemIteratorPtr() )
66 myMesh = ( SMDS_Mesh* ) theMesh;
68 TIDSortedNodeSet nodes;
70 SMDS_NodeIteratorPtr nIt = theMesh->nodesIterator(/*idInceasingOrder=*/true);
72 nodes.insert( nodes.end(), nIt->next() );
76 while ( theElemIt->more() )
78 const SMDS_MeshElement* e = theElemIt->next();
79 nodes.insert( e->begin_nodes(), e->end_nodes() );
82 myOctreeNode = new SMESH_OctreeNode(nodes) ;
84 // get max size of a leaf box
85 SMESH_OctreeNode* tree = myOctreeNode;
86 while ( !tree->isLeaf() )
88 SMESH_OctreeNodeIteratorPtr cIt = tree->GetChildrenIterator();
92 myHalfLeafSize = tree->maxSize() / 2.;
95 //---------------------------------------------------------------------
97 * \brief Move node and update myOctreeNode accordingly
99 void MoveNode( const SMDS_MeshNode* node, const gp_Pnt& toPnt )
101 myOctreeNode->UpdateByMoveNode( node, toPnt );
102 myMesh->MoveNode( node, toPnt.X(), toPnt.Y(), toPnt.Z() );
105 //---------------------------------------------------------------------
109 const SMDS_MeshNode* FindClosestTo( const gp_Pnt& thePnt )
111 map<double, const SMDS_MeshNode*> dist2Nodes;
112 myOctreeNode->NodesAround( thePnt.Coord(), dist2Nodes, myHalfLeafSize );
113 if ( !dist2Nodes.empty() )
114 return dist2Nodes.begin()->second;
115 list<const SMDS_MeshNode*> nodes;
116 //myOctreeNode->NodesAround( &tgtNode, &nodes, myHalfLeafSize );
118 double minSqDist = DBL_MAX;
119 if ( nodes.empty() ) // get all nodes of OctreeNode's closest to thePnt
121 // sort leafs by their distance from thePnt
122 typedef map< double, SMESH_OctreeNode* > TDistTreeMap;
123 TDistTreeMap treeMap;
124 list< SMESH_OctreeNode* > treeList;
125 list< SMESH_OctreeNode* >::iterator trIt;
126 treeList.push_back( myOctreeNode );
128 gp_XYZ pointNode( thePnt.X(), thePnt.Y(), thePnt.Z() );
129 bool pointInside = myOctreeNode->isInside( pointNode, myHalfLeafSize );
130 for ( trIt = treeList.begin(); trIt != treeList.end(); ++trIt)
132 SMESH_OctreeNode* tree = *trIt;
133 if ( !tree->isLeaf() ) // put children to the queue
135 if ( pointInside && !tree->isInside( pointNode, myHalfLeafSize )) continue;
136 SMESH_OctreeNodeIteratorPtr cIt = tree->GetChildrenIterator();
137 while ( cIt->more() )
138 treeList.push_back( cIt->next() );
140 else if ( tree->NbNodes() ) // put a tree to the treeMap
142 const Bnd_B3d& box = *tree->getBox();
143 double sqDist = thePnt.SquareDistance( 0.5 * ( box.CornerMin() + box.CornerMax() ));
144 pair<TDistTreeMap::iterator,bool> it_in = treeMap.insert( make_pair( sqDist, tree ));
145 if ( !it_in.second ) // not unique distance to box center
146 treeMap.insert( it_in.first, make_pair( sqDist + 1e-13*treeMap.size(), tree ));
149 // find distance after which there is no sense to check tree's
150 double sqLimit = DBL_MAX;
151 TDistTreeMap::iterator sqDist_tree = treeMap.begin();
152 if ( treeMap.size() > 5 ) {
153 SMESH_OctreeNode* closestTree = sqDist_tree->second;
154 const Bnd_B3d& box = *closestTree->getBox();
155 double limit = sqrt( sqDist_tree->first ) + sqrt ( box.SquareExtent() );
156 sqLimit = limit * limit;
158 // get all nodes from trees
159 for ( ; sqDist_tree != treeMap.end(); ++sqDist_tree) {
160 if ( sqDist_tree->first > sqLimit )
162 SMESH_OctreeNode* tree = sqDist_tree->second;
163 tree->NodesAround( tree->GetNodeIterator()->next(), &nodes );
166 // find closest among nodes
168 const SMDS_MeshNode* closestNode = 0;
169 list<const SMDS_MeshNode*>::iterator nIt = nodes.begin();
170 for ( ; nIt != nodes.end(); ++nIt ) {
171 double sqDist = thePnt.SquareDistance( SMESH_TNodeXYZ( *nIt ) );
172 if ( minSqDist > sqDist ) {
180 //---------------------------------------------------------------------
182 * \brief Finds nodes located within a tolerance near a point
184 int FindNearPoint(const gp_Pnt& point,
185 const double tolerance,
186 std::vector< const SMDS_MeshNode* >& foundNodes)
188 myOctreeNode->NodesAround( point.Coord(), foundNodes, tolerance );
189 return foundNodes.size();
192 //---------------------------------------------------------------------
196 ~SMESH_NodeSearcherImpl() { delete myOctreeNode; }
198 //---------------------------------------------------------------------
200 * \brief Return the node tree
202 const SMESH_OctreeNode* getTree() const { return myOctreeNode; }
205 SMESH_OctreeNode* myOctreeNode;
207 double myHalfLeafSize; // max size of a leaf box
210 // ========================================================================
211 namespace // Utils used in SMESH_ElementSearcherImpl::FindElementsByPoint()
213 const int MaxNbElemsInLeaf = 10; // maximal number of elements in a leaf of tree
214 const int MaxLevel = 7; // maximal tree height -> nb terminal boxes: 8^7 = 2097152
215 const double NodeRadius = 1e-9; // to enlarge bnd box of element
217 //=======================================================================
219 * \brief Octal tree of bounding boxes of elements
221 //=======================================================================
223 class ElementBndBoxTree : public SMESH_Octree
227 ElementBndBoxTree(const SMDS_Mesh& mesh,
228 SMDSAbs_ElementType elemType,
229 SMDS_ElemIteratorPtr theElemIt = SMDS_ElemIteratorPtr(),
230 double tolerance = NodeRadius );
231 void getElementsNearPoint( const gp_Pnt& point, TIDSortedElemSet& foundElems );
232 void getElementsNearLine ( const gp_Ax1& line, TIDSortedElemSet& foundElems);
233 void getElementsInSphere ( const gp_XYZ& center,
234 const double radius, TIDSortedElemSet& foundElems);
235 size_t getSize() { return std::max( _size, _elements.size() ); }
236 virtual ~ElementBndBoxTree();
239 ElementBndBoxTree():_size(0) {}
240 SMESH_Octree* newChild() const { return new ElementBndBoxTree; }
241 void buildChildrenData();
242 Bnd_B3d* buildRootBox();
244 //!< Bounding box of element
245 struct ElementBox : public Bnd_B3d
247 const SMDS_MeshElement* _element;
248 int _refCount; // an ElementBox can be included in several tree branches
249 ElementBox(const SMDS_MeshElement* elem, double tolerance);
251 vector< ElementBox* > _elements;
255 //================================================================================
257 * \brief ElementBndBoxTree creation
259 //================================================================================
261 ElementBndBoxTree::ElementBndBoxTree(const SMDS_Mesh& mesh, SMDSAbs_ElementType elemType, SMDS_ElemIteratorPtr theElemIt, double tolerance)
262 :SMESH_Octree( new SMESH_TreeLimit( MaxLevel, /*minSize=*/0. ))
264 int nbElems = mesh.GetMeshInfo().NbElements( elemType );
265 _elements.reserve( nbElems );
267 SMDS_ElemIteratorPtr elemIt = theElemIt ? theElemIt : mesh.elementsIterator( elemType );
268 while ( elemIt->more() )
269 _elements.push_back( new ElementBox( elemIt->next(),tolerance ));
274 //================================================================================
278 //================================================================================
280 ElementBndBoxTree::~ElementBndBoxTree()
282 for ( size_t i = 0; i < _elements.size(); ++i )
283 if ( --_elements[i]->_refCount <= 0 )
287 //================================================================================
289 * \brief Return the maximal box
291 //================================================================================
293 Bnd_B3d* ElementBndBoxTree::buildRootBox()
295 Bnd_B3d* box = new Bnd_B3d;
296 for ( size_t i = 0; i < _elements.size(); ++i )
297 box->Add( *_elements[i] );
301 //================================================================================
303 * \brief Redistrubute element boxes among children
305 //================================================================================
307 void ElementBndBoxTree::buildChildrenData()
309 for ( size_t i = 0; i < _elements.size(); ++i )
311 for (int j = 0; j < 8; j++)
313 if ( !_elements[i]->IsOut( *myChildren[j]->getBox() ))
315 _elements[i]->_refCount++;
316 ((ElementBndBoxTree*)myChildren[j])->_elements.push_back( _elements[i]);
319 _elements[i]->_refCount--;
321 _size = _elements.size();
322 SMESHUtils::FreeVector( _elements ); // = _elements.clear() + free memory
324 for (int j = 0; j < 8; j++)
326 ElementBndBoxTree* child = static_cast<ElementBndBoxTree*>( myChildren[j]);
327 if ((int) child->_elements.size() <= MaxNbElemsInLeaf )
328 child->myIsLeaf = true;
330 if ( child->_elements.capacity() - child->_elements.size() > 1000 )
331 SMESHUtils::CompactVector( child->_elements );
335 //================================================================================
337 * \brief Return elements which can include the point
339 //================================================================================
341 void ElementBndBoxTree::getElementsNearPoint( const gp_Pnt& point,
342 TIDSortedElemSet& foundElems)
344 if ( getBox()->IsOut( point.XYZ() ))
349 for ( size_t i = 0; i < _elements.size(); ++i )
350 if ( !_elements[i]->IsOut( point.XYZ() ))
351 foundElems.insert( _elements[i]->_element );
355 for (int i = 0; i < 8; i++)
356 ((ElementBndBoxTree*) myChildren[i])->getElementsNearPoint( point, foundElems );
360 //================================================================================
362 * \brief Return elements which can be intersected by the line
364 //================================================================================
366 void ElementBndBoxTree::getElementsNearLine( const gp_Ax1& line,
367 TIDSortedElemSet& foundElems)
369 if ( getBox()->IsOut( line ))
374 for ( size_t i = 0; i < _elements.size(); ++i )
375 if ( !_elements[i]->IsOut( line ))
376 foundElems.insert( _elements[i]->_element );
380 for (int i = 0; i < 8; i++)
381 ((ElementBndBoxTree*) myChildren[i])->getElementsNearLine( line, foundElems );
385 //================================================================================
387 * \brief Return elements from leaves intersecting the sphere
389 //================================================================================
391 void ElementBndBoxTree::getElementsInSphere ( const gp_XYZ& center,
393 TIDSortedElemSet& foundElems)
395 if ( getBox()->IsOut( center, radius ))
400 for ( size_t i = 0; i < _elements.size(); ++i )
401 if ( !_elements[i]->IsOut( center, radius ))
402 foundElems.insert( _elements[i]->_element );
406 for (int i = 0; i < 8; i++)
407 ((ElementBndBoxTree*) myChildren[i])->getElementsInSphere( center, radius, foundElems );
411 //================================================================================
413 * \brief Construct the element box
415 //================================================================================
417 ElementBndBoxTree::ElementBox::ElementBox(const SMDS_MeshElement* elem, double tolerance)
421 SMDS_ElemIteratorPtr nIt = elem->nodesIterator();
422 while ( nIt->more() )
423 Add( SMESH_TNodeXYZ( nIt->next() ));
424 Enlarge( tolerance );
429 //=======================================================================
431 * \brief Implementation of search for the elements by point and
432 * of classification of point in 2D mesh
434 //=======================================================================
436 SMESH_ElementSearcher::~SMESH_ElementSearcher()
440 struct SMESH_ElementSearcherImpl: public SMESH_ElementSearcher
443 SMDS_ElemIteratorPtr _meshPartIt;
444 ElementBndBoxTree* _ebbTree [SMDSAbs_NbElementTypes];
445 int _ebbTreeHeight[SMDSAbs_NbElementTypes];
446 SMESH_NodeSearcherImpl* _nodeSearcher;
447 SMDSAbs_ElementType _elementType;
449 bool _outerFacesFound;
450 set<const SMDS_MeshElement*> _outerFaces; // empty means "no internal faces at all"
452 SMESH_ElementSearcherImpl( SMDS_Mesh& mesh,
454 SMDS_ElemIteratorPtr elemIt=SMDS_ElemIteratorPtr())
455 : _mesh(&mesh),_meshPartIt(elemIt),_nodeSearcher(0),_tolerance(tol),_outerFacesFound(false)
457 for ( int i = 0; i < SMDSAbs_NbElementTypes; ++i )
460 _ebbTreeHeight[i] = -1;
462 _elementType = SMDSAbs_All;
464 virtual ~SMESH_ElementSearcherImpl()
466 for ( int i = 0; i < SMDSAbs_NbElementTypes; ++i )
468 delete _ebbTree[i]; _ebbTree[i] = NULL;
470 if ( _nodeSearcher ) delete _nodeSearcher; _nodeSearcher = 0;
472 virtual int FindElementsByPoint(const gp_Pnt& point,
473 SMDSAbs_ElementType type,
474 vector< const SMDS_MeshElement* >& foundElements);
475 virtual TopAbs_State GetPointState(const gp_Pnt& point);
476 virtual const SMDS_MeshElement* FindClosestTo( const gp_Pnt& point,
477 SMDSAbs_ElementType type );
479 void GetElementsNearLine( const gp_Ax1& line,
480 SMDSAbs_ElementType type,
481 vector< const SMDS_MeshElement* >& foundElems);
482 void GetElementsInSphere( const gp_XYZ& center,
484 SMDSAbs_ElementType type,
485 vector< const SMDS_MeshElement* >& foundElems);
486 double getTolerance();
487 bool getIntersParamOnLine(const gp_Lin& line, const SMDS_MeshElement* face,
488 const double tolerance, double & param);
489 void findOuterBoundary(const SMDS_MeshElement* anyOuterFace);
490 bool isOuterBoundary(const SMDS_MeshElement* face) const
492 return _outerFaces.empty() || _outerFaces.count(face);
496 if ( _ebbTreeHeight[ _elementType ] < 0 )
497 _ebbTreeHeight[ _elementType ] = _ebbTree[ _elementType ]->getHeight();
498 return _ebbTreeHeight[ _elementType ];
501 struct TInters //!< data of intersection of the line and the mesh face (used in GetPointState())
503 const SMDS_MeshElement* _face;
505 bool _coincides; //!< the line lays in face plane
506 TInters(const SMDS_MeshElement* face, const gp_Vec& faceNorm, bool coinc=false)
507 : _face(face), _faceNorm( faceNorm ), _coincides( coinc ) {}
509 struct TFaceLink //!< link and faces sharing it (used in findOuterBoundary())
512 TIDSortedElemSet _faces;
513 TFaceLink( const SMDS_MeshNode* n1, const SMDS_MeshNode* n2, const SMDS_MeshElement* face)
514 : _link( n1, n2 ), _faces( &face, &face + 1) {}
518 ostream& operator<< (ostream& out, const SMESH_ElementSearcherImpl::TInters& i)
520 return out << "TInters(face=" << ( i._face ? i._face->GetID() : 0)
521 << ", _coincides="<<i._coincides << ")";
524 //=======================================================================
526 * \brief define tolerance for search
528 //=======================================================================
530 double SMESH_ElementSearcherImpl::getTolerance()
532 if ( _tolerance < 0 )
534 const SMDS_MeshInfo& meshInfo = _mesh->GetMeshInfo();
537 if ( _nodeSearcher && meshInfo.NbNodes() > 1 )
539 double boxSize = _nodeSearcher->getTree()->maxSize();
540 _tolerance = 1e-8 * boxSize/* / meshInfo.NbNodes()*/;
542 else if ( _ebbTree[_elementType] && meshInfo.NbElements() > 0 )
544 double boxSize = _ebbTree[_elementType]->maxSize();
545 _tolerance = 1e-8 * boxSize/* / meshInfo.NbElements()*/;
547 if ( _tolerance == 0 )
549 // define tolerance by size of a most complex element
550 int complexType = SMDSAbs_Volume;
551 while ( complexType > SMDSAbs_All &&
552 meshInfo.NbElements( SMDSAbs_ElementType( complexType )) < 1 )
554 if ( complexType == SMDSAbs_All ) return 0; // empty mesh
556 if ( complexType == int( SMDSAbs_Node ))
558 SMDS_NodeIteratorPtr nodeIt = _mesh->nodesIterator();
560 if ( meshInfo.NbNodes() > 2 )
561 elemSize = SMESH_TNodeXYZ( nodeIt->next() ).Distance( nodeIt->next() );
565 SMDS_ElemIteratorPtr elemIt = _mesh->elementsIterator( SMDSAbs_ElementType( complexType ));
566 const SMDS_MeshElement* elem = elemIt->next();
567 SMDS_ElemIteratorPtr nodeIt = elem->nodesIterator();
568 SMESH_TNodeXYZ n1( nodeIt->next() );
570 while ( nodeIt->more() )
572 double dist = n1.Distance( static_cast<const SMDS_MeshNode*>( nodeIt->next() ));
573 elemSize = max( dist, elemSize );
576 _tolerance = 1e-4 * elemSize;
582 //================================================================================
584 * \brief Find intersection of the line and an edge of face and return parameter on line
586 //================================================================================
588 bool SMESH_ElementSearcherImpl::getIntersParamOnLine(const gp_Lin& line,
589 const SMDS_MeshElement* face,
596 GeomAPI_ExtremaCurveCurve anExtCC;
597 Handle(Geom_Curve) lineCurve = new Geom_Line( line );
599 int nbNodes = face->IsQuadratic() ? face->NbNodes()/2 : face->NbNodes();
600 for ( int i = 0; i < nbNodes && nbInts < 2; ++i )
602 GC_MakeSegment edge( SMESH_TNodeXYZ( face->GetNode( i )),
603 SMESH_TNodeXYZ( face->GetNode( (i+1)%nbNodes) ));
604 anExtCC.Init( lineCurve, edge.Value() );
605 if ( anExtCC.NbExtrema() > 0 && anExtCC.LowerDistance() <= tol)
607 Quantity_Parameter pl, pe;
608 anExtCC.LowerDistanceParameters( pl, pe );
614 if ( nbInts > 0 ) param /= nbInts;
617 //================================================================================
619 * \brief Find all faces belonging to the outer boundary of mesh
621 //================================================================================
623 void SMESH_ElementSearcherImpl::findOuterBoundary(const SMDS_MeshElement* outerFace)
625 if ( _outerFacesFound ) return;
627 // Collect all outer faces by passing from one outer face to another via their links
628 // and BTW find out if there are internal faces at all.
630 // checked links and links where outer boundary meets internal one
631 set< SMESH_TLink > visitedLinks, seamLinks;
633 // links to treat with already visited faces sharing them
634 list < TFaceLink > startLinks;
636 // load startLinks with the first outerFace
637 startLinks.push_back( TFaceLink( outerFace->GetNode(0), outerFace->GetNode(1), outerFace));
638 _outerFaces.insert( outerFace );
640 TIDSortedElemSet emptySet;
641 while ( !startLinks.empty() )
643 const SMESH_TLink& link = startLinks.front()._link;
644 TIDSortedElemSet& faces = startLinks.front()._faces;
646 outerFace = *faces.begin();
647 // find other faces sharing the link
648 const SMDS_MeshElement* f;
649 while (( f = SMESH_MeshAlgos::FindFaceInSet(link.node1(), link.node2(), emptySet, faces )))
652 // select another outer face among the found
653 const SMDS_MeshElement* outerFace2 = 0;
654 if ( faces.size() == 2 )
656 outerFace2 = (outerFace == *faces.begin() ? *faces.rbegin() : *faces.begin());
658 else if ( faces.size() > 2 )
660 seamLinks.insert( link );
662 // link direction within the outerFace
663 gp_Vec n1n2( SMESH_TNodeXYZ( link.node1()),
664 SMESH_TNodeXYZ( link.node2()));
665 int i1 = outerFace->GetNodeIndex( link.node1() );
666 int i2 = outerFace->GetNodeIndex( link.node2() );
667 bool rev = ( abs(i2-i1) == 1 ? i1 > i2 : i2 > i1 );
668 if ( rev ) n1n2.Reverse();
670 gp_XYZ ofNorm, fNorm;
671 if ( SMESH_MeshAlgos::FaceNormal( outerFace, ofNorm, /*normalized=*/false ))
673 // direction from the link inside outerFace
674 gp_Vec dirInOF = gp_Vec( ofNorm ) ^ n1n2;
675 // sort all other faces by angle with the dirInOF
676 map< double, const SMDS_MeshElement* > angle2Face;
677 set< const SMDS_MeshElement*, TIDCompare >::const_iterator face = faces.begin();
678 for ( ; face != faces.end(); ++face )
680 if ( *face == outerFace ) continue;
681 if ( !SMESH_MeshAlgos::FaceNormal( *face, fNorm, /*normalized=*/false ))
683 gp_Vec dirInF = gp_Vec( fNorm ) ^ n1n2;
684 double angle = dirInOF.AngleWithRef( dirInF, n1n2 );
685 if ( angle < 0 ) angle += 2. * M_PI;
686 angle2Face.insert( make_pair( angle, *face ));
688 if ( !angle2Face.empty() )
689 outerFace2 = angle2Face.begin()->second;
692 // store the found outer face and add its links to continue seaching from
695 _outerFaces.insert( outerFace2 );
696 int nbNodes = outerFace2->NbCornerNodes();
697 for ( int i = 0; i < nbNodes; ++i )
699 SMESH_TLink link2( outerFace2->GetNode(i), outerFace2->GetNode((i+1)%nbNodes));
700 if ( visitedLinks.insert( link2 ).second )
701 startLinks.push_back( TFaceLink( link2.node1(), link2.node2(), outerFace2 ));
704 startLinks.pop_front();
706 _outerFacesFound = true;
708 if ( !seamLinks.empty() )
710 // There are internal boundaries touching the outher one,
711 // find all faces of internal boundaries in order to find
712 // faces of boundaries of holes, if any.
721 //=======================================================================
723 * \brief Find elements of given type where the given point is IN or ON.
724 * Returns nb of found elements and elements them-selves.
726 * 'ALL' type means elements of any type excluding nodes, balls and 0D elements
728 //=======================================================================
730 int SMESH_ElementSearcherImpl::
731 FindElementsByPoint(const gp_Pnt& point,
732 SMDSAbs_ElementType type,
733 vector< const SMDS_MeshElement* >& foundElements)
735 foundElements.clear();
738 double tolerance = getTolerance();
740 // =================================================================================
741 if ( type == SMDSAbs_Node || type == SMDSAbs_0DElement || type == SMDSAbs_Ball)
743 if ( !_nodeSearcher )
746 _nodeSearcher = new SMESH_NodeSearcherImpl( 0, _meshPartIt );
748 _nodeSearcher = new SMESH_NodeSearcherImpl( _mesh );
750 std::vector< const SMDS_MeshNode* > foundNodes;
751 _nodeSearcher->FindNearPoint( point, tolerance, foundNodes );
753 if ( type == SMDSAbs_Node )
755 foundElements.assign( foundNodes.begin(), foundNodes.end() );
759 for ( size_t i = 0; i < foundNodes.size(); ++i )
761 SMDS_ElemIteratorPtr elemIt = foundNodes[i]->GetInverseElementIterator( type );
762 while ( elemIt->more() )
763 foundElements.push_back( elemIt->next() );
767 // =================================================================================
768 else // elements more complex than 0D
770 if ( !_ebbTree[type] )
772 _ebbTree[_elementType] = new ElementBndBoxTree( *_mesh, type, _meshPartIt, tolerance );
774 TIDSortedElemSet suspectElems;
775 _ebbTree[ type ]->getElementsNearPoint( point, suspectElems );
776 TIDSortedElemSet::iterator elem = suspectElems.begin();
777 for ( ; elem != suspectElems.end(); ++elem )
778 if ( !SMESH_MeshAlgos::IsOut( *elem, point, tolerance ))
779 foundElements.push_back( *elem );
781 return foundElements.size();
784 //=======================================================================
786 * \brief Find an element of given type most close to the given point
788 * WARNING: Only face search is implemeneted so far
790 //=======================================================================
792 const SMDS_MeshElement*
793 SMESH_ElementSearcherImpl::FindClosestTo( const gp_Pnt& point,
794 SMDSAbs_ElementType type )
796 const SMDS_MeshElement* closestElem = 0;
799 if ( type == SMDSAbs_Face || type == SMDSAbs_Volume )
801 ElementBndBoxTree*& ebbTree = _ebbTree[ type ];
803 ebbTree = new ElementBndBoxTree( *_mesh, type, _meshPartIt );
805 TIDSortedElemSet suspectElems;
806 ebbTree->getElementsNearPoint( point, suspectElems );
808 if ( suspectElems.empty() && ebbTree->maxSize() > 0 )
810 gp_Pnt boxCenter = 0.5 * ( ebbTree->getBox()->CornerMin() +
811 ebbTree->getBox()->CornerMax() );
813 if ( ebbTree->getBox()->IsOut( point.XYZ() ))
814 radius = point.Distance( boxCenter ) - 0.5 * ebbTree->maxSize();
816 radius = ebbTree->maxSize() / pow( 2., getTreeHeight()) / 2;
817 while ( suspectElems.empty() )
819 ebbTree->getElementsInSphere( point.XYZ(), radius, suspectElems );
823 double minDist = std::numeric_limits<double>::max();
824 multimap< double, const SMDS_MeshElement* > dist2face;
825 TIDSortedElemSet::iterator elem = suspectElems.begin();
826 for ( ; elem != suspectElems.end(); ++elem )
828 double dist = SMESH_MeshAlgos::GetDistance( *elem, point );
829 if ( dist < minDist + 1e-10)
832 dist2face.insert( dist2face.begin(), make_pair( dist, *elem ));
835 if ( !dist2face.empty() )
837 multimap< double, const SMDS_MeshElement* >::iterator d2f = dist2face.begin();
838 closestElem = d2f->second;
839 // if there are several elements at the same distance, select one
840 // with GC closest to the point
841 typedef SMDS_StdIterator< SMESH_TNodeXYZ, SMDS_ElemIteratorPtr > TXyzIterator;
842 double minDistToGC = 0;
843 for ( ++d2f; d2f != dist2face.end() && fabs( d2f->first - minDist ) < 1e-10; ++d2f )
845 if ( minDistToGC == 0 )
848 gc = accumulate( TXyzIterator(closestElem->nodesIterator()),
849 TXyzIterator(), gc ) / closestElem->NbNodes();
850 minDistToGC = point.SquareDistance( gc );
853 gc = accumulate( TXyzIterator( d2f->second->nodesIterator()),
854 TXyzIterator(), gc ) / d2f->second->NbNodes();
855 double d = point.SquareDistance( gc );
856 if ( d < minDistToGC )
859 closestElem = d2f->second;
862 // cout << "FindClosestTo( " <<point.X()<<", "<<point.Y()<<", "<<point.Z()<<" ) FACE "
863 // <<closestElem->GetID() << " DIST " << minDist << endl;
868 // NOT IMPLEMENTED SO FAR
874 //================================================================================
876 * \brief Classify the given point in the closed 2D mesh
878 //================================================================================
880 TopAbs_State SMESH_ElementSearcherImpl::GetPointState(const gp_Pnt& point)
882 _elementType = SMDSAbs_Face;
884 double tolerance = getTolerance();
886 ElementBndBoxTree*& ebbTree = _ebbTree[ SMDSAbs_Face ];
888 ebbTree = new ElementBndBoxTree( *_mesh, _elementType, _meshPartIt );
890 // Algo: analyse transition of a line starting at the point through mesh boundary;
891 // try three lines parallel to axis of the coordinate system and perform rough
892 // analysis. If solution is not clear perform thorough analysis.
894 const int nbAxes = 3;
895 gp_Dir axisDir[ nbAxes ] = { gp::DX(), gp::DY(), gp::DZ() };
896 map< double, TInters > paramOnLine2TInters[ nbAxes ];
897 list< TInters > tangentInters[ nbAxes ]; // of faces whose plane includes the line
898 multimap< int, int > nbInt2Axis; // to find the simplest case
899 for ( int axis = 0; axis < nbAxes; ++axis )
901 gp_Ax1 lineAxis( point, axisDir[axis]);
902 gp_Lin line ( lineAxis );
904 TIDSortedElemSet suspectFaces; // faces possibly intersecting the line
905 ebbTree->getElementsNearLine( lineAxis, suspectFaces );
907 // Intersect faces with the line
909 map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
910 TIDSortedElemSet::iterator face = suspectFaces.begin();
911 for ( ; face != suspectFaces.end(); ++face )
915 if ( !SMESH_MeshAlgos::FaceNormal( *face, fNorm, /*normalized=*/false)) continue;
916 gp_Pln facePlane( SMESH_TNodeXYZ( (*face)->GetNode(0)), fNorm );
918 // perform intersection
919 IntAna_IntConicQuad intersection( line, IntAna_Quadric( facePlane ));
920 if ( !intersection.IsDone() )
922 if ( intersection.IsInQuadric() )
924 tangentInters[ axis ].push_back( TInters( *face, fNorm, true ));
926 else if ( ! intersection.IsParallel() && intersection.NbPoints() > 0 )
928 double tol = 1e-4 * Sqrt( fNorm.Modulus() );
929 gp_Pnt intersectionPoint = intersection.Point(1);
930 if ( !SMESH_MeshAlgos::IsOut( *face, intersectionPoint, tol ))
931 u2inters.insert(make_pair( intersection.ParamOnConic(1), TInters( *face, fNorm )));
934 // Analyse intersections roughly
936 int nbInter = u2inters.size();
940 double f = u2inters.begin()->first, l = u2inters.rbegin()->first;
941 if ( nbInter == 1 ) // not closed mesh
942 return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
944 if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
947 if ( (f<0) == (l<0) )
950 int nbIntBeforePoint = std::distance( u2inters.begin(), u2inters.lower_bound(0));
951 int nbIntAfterPoint = nbInter - nbIntBeforePoint;
952 if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
955 nbInt2Axis.insert( make_pair( min( nbIntBeforePoint, nbIntAfterPoint ), axis ));
957 if ( _outerFacesFound ) break; // pass to thorough analysis
959 } // three attempts - loop on CS axes
961 // Analyse intersections thoroughly.
962 // We make two loops maximum, on the first one we only exclude touching intersections,
963 // on the second, if situation is still unclear, we gather and use information on
964 // position of faces (internal or outer). If faces position is already gathered,
965 // we make the second loop right away.
967 for ( int hasPositionInfo = _outerFacesFound; hasPositionInfo < 2; ++hasPositionInfo )
969 multimap< int, int >::const_iterator nb_axis = nbInt2Axis.begin();
970 for ( ; nb_axis != nbInt2Axis.end(); ++nb_axis )
972 int axis = nb_axis->second;
973 map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
975 gp_Ax1 lineAxis( point, axisDir[axis]);
976 gp_Lin line ( lineAxis );
978 // add tangent intersections to u2inters
980 list< TInters >::const_iterator tgtInt = tangentInters[ axis ].begin();
981 for ( ; tgtInt != tangentInters[ axis ].end(); ++tgtInt )
982 if ( getIntersParamOnLine( line, tgtInt->_face, tolerance, param ))
983 u2inters.insert(make_pair( param, *tgtInt ));
984 tangentInters[ axis ].clear();
986 // Count intersections before and after the point excluding touching ones.
987 // If hasPositionInfo we count intersections of outer boundary only
989 int nbIntBeforePoint = 0, nbIntAfterPoint = 0;
990 double f = numeric_limits<double>::max(), l = -numeric_limits<double>::max();
991 map< double, TInters >::iterator u_int1 = u2inters.begin(), u_int2 = u_int1;
992 bool ok = ! u_int1->second._coincides;
993 while ( ok && u_int1 != u2inters.end() )
995 double u = u_int1->first;
996 bool touchingInt = false;
997 if ( ++u_int2 != u2inters.end() )
999 // skip intersections at the same point (if the line passes through edge or node)
1001 while ( u_int2 != u2inters.end() && fabs( u_int2->first - u ) < tolerance )
1007 // skip tangent intersections
1009 if ( u_int2 != u2inters.end() )
1011 const SMDS_MeshElement* prevFace = u_int1->second._face;
1012 while ( ok && u_int2->second._coincides )
1014 if ( SMESH_MeshAlgos::GetCommonNodes(prevFace , u_int2->second._face).empty() )
1020 ok = ( u_int2 != u2inters.end() );
1026 // skip intersections at the same point after tangent intersections
1029 double u2 = u_int2->first;
1031 while ( u_int2 != u2inters.end() && fabs( u_int2->first - u2 ) < tolerance )
1037 // decide if we skipped a touching intersection
1038 if ( nbSamePnt + nbTgt > 0 )
1040 double minDot = numeric_limits<double>::max(), maxDot = -numeric_limits<double>::max();
1041 map< double, TInters >::iterator u_int = u_int1;
1042 for ( ; u_int != u_int2; ++u_int )
1044 if ( u_int->second._coincides ) continue;
1045 double dot = u_int->second._faceNorm * line.Direction();
1046 if ( dot > maxDot ) maxDot = dot;
1047 if ( dot < minDot ) minDot = dot;
1049 touchingInt = ( minDot*maxDot < 0 );
1054 if ( !hasPositionInfo || isOuterBoundary( u_int1->second._face ))
1065 u_int1 = u_int2; // to next intersection
1067 } // loop on intersections with one line
1071 if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
1074 if ( nbIntBeforePoint == 0 || nbIntAfterPoint == 0)
1077 if ( nbIntBeforePoint + nbIntAfterPoint == 1 ) // not closed mesh
1078 return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
1080 if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
1083 if ( (f<0) == (l<0) )
1086 if ( hasPositionInfo )
1087 return nbIntBeforePoint % 2 ? TopAbs_IN : TopAbs_OUT;
1089 } // loop on intersections of the tree lines - thorough analysis
1091 if ( !hasPositionInfo )
1093 // gather info on faces position - is face in the outer boundary or not
1094 map< double, TInters > & u2inters = paramOnLine2TInters[ 0 ];
1095 findOuterBoundary( u2inters.begin()->second._face );
1098 } // two attempts - with and w/o faces position info in the mesh
1100 return TopAbs_UNKNOWN;
1103 //=======================================================================
1105 * \brief Return elements possibly intersecting the line
1107 //=======================================================================
1109 void SMESH_ElementSearcherImpl::GetElementsNearLine( const gp_Ax1& line,
1110 SMDSAbs_ElementType type,
1111 vector< const SMDS_MeshElement* >& foundElems)
1113 _elementType = type;
1114 ElementBndBoxTree*& ebbTree = _ebbTree[ type ];
1116 ebbTree = new ElementBndBoxTree( *_mesh, _elementType, _meshPartIt );
1118 TIDSortedElemSet suspectFaces; // elements possibly intersecting the line
1119 ebbTree->getElementsNearLine( line, suspectFaces );
1120 foundElems.assign( suspectFaces.begin(), suspectFaces.end());
1123 //=======================================================================
1125 * Return elements whose bounding box intersects a sphere
1127 //=======================================================================
1129 void SMESH_ElementSearcherImpl::GetElementsInSphere( const gp_XYZ& center,
1130 const double radius,
1131 SMDSAbs_ElementType type,
1132 vector< const SMDS_MeshElement* >& foundElems)
1134 _elementType = type;
1135 ElementBndBoxTree*& ebbTree = _ebbTree[ type ];
1137 ebbTree = new ElementBndBoxTree( *_mesh, _elementType, _meshPartIt );
1139 TIDSortedElemSet suspectFaces; // elements possibly intersecting the line
1140 ebbTree->getElementsInSphere( center, radius, suspectFaces );
1141 foundElems.assign( suspectFaces.begin(), suspectFaces.end() );
1144 //=======================================================================
1146 * \brief Return true if the point is IN or ON of the element
1148 //=======================================================================
1150 bool SMESH_MeshAlgos::IsOut( const SMDS_MeshElement* element, const gp_Pnt& point, double tol )
1152 if ( element->GetType() == SMDSAbs_Volume)
1154 return SMDS_VolumeTool( element ).IsOut( point.X(), point.Y(), point.Z(), tol );
1157 // get ordered nodes
1159 vector< SMESH_TNodeXYZ > xyz; xyz.reserve( element->NbNodes()+1 );
1161 SMDS_ElemIteratorPtr nodeIt = element->interlacedNodesElemIterator();
1162 for ( int i = 0; nodeIt->more(); ++i )
1163 xyz.push_back( SMESH_TNodeXYZ( nodeIt->next() ));
1165 int i, nbNodes = (int) xyz.size(); // central node of biquadratic is missing
1167 if ( element->GetType() == SMDSAbs_Face ) // --------------------------------------------------
1169 // compute face normal
1170 gp_Vec faceNorm(0,0,0);
1171 xyz.push_back( xyz.front() );
1172 for ( i = 0; i < nbNodes; ++i )
1174 gp_Vec edge1( xyz[i+1], xyz[i]);
1175 gp_Vec edge2( xyz[i+1], xyz[(i+2)%nbNodes] );
1176 faceNorm += edge1 ^ edge2;
1178 double fNormSize = faceNorm.Magnitude();
1179 if ( fNormSize <= tol )
1181 // degenerated face: point is out if it is out of all face edges
1182 for ( i = 0; i < nbNodes; ++i )
1184 SMDS_LinearEdge edge( xyz[i]._node, xyz[i+1]._node );
1185 if ( !IsOut( &edge, point, tol ))
1190 faceNorm /= fNormSize;
1192 // check if the point lays on face plane
1193 gp_Vec n2p( xyz[0], point );
1194 double dot = n2p * faceNorm;
1195 if ( Abs( dot ) > tol ) // not on face plane
1198 if ( nbNodes > 3 ) // maybe the face is not planar
1200 double elemThick = 0;
1201 for ( i = 1; i < nbNodes; ++i )
1203 gp_Vec n2n( xyz[0], xyz[i] );
1204 elemThick = Max( elemThick, Abs( n2n * faceNorm ));
1206 isOut = Abs( dot ) > elemThick + tol;
1212 // check if point is out of face boundary:
1213 // define it by closest transition of a ray point->infinity through face boundary
1214 // on the face plane.
1215 // First, find normal of a plane perpendicular to face plane, to be used as a cutting tool
1216 // to find intersections of the ray with the boundary.
1218 gp_Vec plnNorm = ray ^ faceNorm;
1219 double n2pSize = plnNorm.Magnitude();
1220 if ( n2pSize <= tol ) return false; // point coincides with the first node
1221 if ( n2pSize * n2pSize > fNormSize * 100 ) return true; // point is very far
1223 // for each node of the face, compute its signed distance to the cutting plane
1224 vector<double> dist( nbNodes + 1);
1225 for ( i = 0; i < nbNodes; ++i )
1227 gp_Vec n2p( xyz[i], point );
1228 dist[i] = n2p * plnNorm;
1230 dist.back() = dist.front();
1231 // find the closest intersection
1233 double rClosest = 0, distClosest = 1e100;
1235 for ( i = 0; i < nbNodes; ++i )
1238 if ( fabs( dist[i] ) < tol )
1240 else if ( fabs( dist[i+1]) < tol )
1242 else if ( dist[i] * dist[i+1] < 0 )
1243 r = dist[i] / ( dist[i] - dist[i+1] );
1245 continue; // no intersection
1246 gp_Pnt pInt = xyz[i] * (1.-r) + xyz[i+1] * r;
1247 gp_Vec p2int( point, pInt);
1248 double intDist = p2int.SquareMagnitude();
1249 if ( intDist < distClosest )
1254 distClosest = intDist;
1258 return true; // no intesections - out
1260 // analyse transition
1261 gp_Vec edge( xyz[iClosest], xyz[iClosest+1] );
1262 gp_Vec edgeNorm = -( edge ^ faceNorm ); // normal to intersected edge pointing out of face
1263 gp_Vec p2int ( point, pClosest );
1264 bool out = (edgeNorm * p2int) < -tol;
1265 if ( rClosest > 0. && rClosest < 1. ) // not node intersection
1268 // the ray passes through a face node; analyze transition through an adjacent edge
1269 gp_Pnt p1 = xyz[ (rClosest == 0.) ? ((iClosest+nbNodes-1) % nbNodes) : (iClosest+1) ];
1270 gp_Pnt p2 = xyz[ (rClosest == 0.) ? iClosest : ((iClosest+2) % nbNodes) ];
1271 gp_Vec edgeAdjacent( p1, p2 );
1272 gp_Vec edgeNorm2 = -( edgeAdjacent ^ faceNorm );
1273 bool out2 = (edgeNorm2 * p2int) < -tol;
1275 bool covexCorner = ( edgeNorm * edgeAdjacent * (rClosest==1. ? 1. : -1.)) < 0;
1276 return covexCorner ? (out || out2) : (out && out2);
1279 if ( element->GetType() == SMDSAbs_Edge ) // --------------------------------------------------
1281 // point is out of edge if it is NOT ON any straight part of edge
1282 // (we consider quadratic edge as being composed of two straight parts)
1283 for ( i = 1; i < nbNodes; ++i )
1285 gp_Vec edge( xyz[i-1], xyz[i] );
1286 gp_Vec n1p ( xyz[i-1], point );
1287 double u = ( edge * n1p ) / edge.SquareMagnitude(); // param [0,1] on the edge
1289 if ( n1p.SquareMagnitude() < tol * tol )
1294 if ( point.SquareDistance( xyz[i] ) < tol * tol )
1298 gp_XYZ proj = ( 1. - u ) * xyz[i-1] + u * xyz[i]; // projection of the point on the edge
1299 double dist2 = point.SquareDistance( proj );
1300 if ( dist2 > tol * tol )
1302 return false; // point is ON this part
1307 // Node or 0D element -------------------------------------------------------------------------
1309 gp_Vec n2p ( xyz[0], point );
1310 return n2p.SquareMagnitude() > tol * tol;
1315 //=======================================================================
1318 // Position of a point relative to a segment
1322 // VERTEX 1 o----ON-----> VERTEX 2
1326 enum PositionName { POS_LEFT = 1, POS_VERTEX = 2, POS_RIGHT = 4, //POS_ON = 8,
1327 POS_ALL = POS_LEFT | POS_RIGHT | POS_VERTEX };
1331 int _index; // index of vertex or segment
1333 PointPos( PositionName n, int i=-1 ): _name(n), _index(i) {}
1334 bool operator < (const PointPos& other ) const
1336 if ( _name == other._name )
1337 return ( _index < 0 || other._index < 0 ) ? false : _index < other._index;
1338 return _name < other._name;
1342 //================================================================================
1344 * \brief Return of a point relative to a segment
1345 * \param point2D - the point to analyze position of
1346 * \param xyVec - end points of segments
1347 * \param index0 - 0-based index of the first point of segment
1348 * \param posToFindOut - flags of positions to detect
1349 * \retval PointPos - point position
1351 //================================================================================
1353 PointPos getPointPosition( const gp_XY& point2D,
1354 const gp_XY* segEnds,
1355 const int index0 = 0,
1356 const int posToFindOut = POS_ALL)
1358 const gp_XY& p1 = segEnds[ index0 ];
1359 const gp_XY& p2 = segEnds[ index0+1 ];
1360 const gp_XY grad = p2 - p1;
1362 if ( posToFindOut & POS_VERTEX )
1364 // check if the point2D is at "vertex 1" zone
1365 gp_XY pp1[2] = { p1, gp_XY( p1.X() - grad.Y(),
1366 p1.Y() + grad.X() ) };
1367 if ( getPointPosition( point2D, pp1, 0, POS_LEFT|POS_RIGHT )._name == POS_LEFT )
1368 return PointPos( POS_VERTEX, index0 );
1370 // check if the point2D is at "vertex 2" zone
1371 gp_XY pp2[2] = { p2, gp_XY( p2.X() - grad.Y(),
1372 p2.Y() + grad.X() ) };
1373 if ( getPointPosition( point2D, pp2, 0, POS_LEFT|POS_RIGHT )._name == POS_RIGHT )
1374 return PointPos( POS_VERTEX, index0 + 1);
1376 double edgeEquation =
1377 ( point2D.X() - p1.X() ) * grad.Y() - ( point2D.Y() - p1.Y() ) * grad.X();
1378 return PointPos( edgeEquation < 0 ? POS_LEFT : POS_RIGHT, index0 );
1382 //=======================================================================
1384 * \brief Return minimal distance from a point to an element
1386 * Currently we ignore non-planarity and 2nd order of face
1388 //=======================================================================
1390 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshElement* elem,
1391 const gp_Pnt& point )
1393 switch ( elem->GetType() )
1395 case SMDSAbs_Volume:
1396 return GetDistance( dynamic_cast<const SMDS_MeshVolume*>( elem ), point);
1398 return GetDistance( dynamic_cast<const SMDS_MeshFace*>( elem ), point);
1400 return GetDistance( dynamic_cast<const SMDS_MeshEdge*>( elem ), point);
1402 return point.Distance( SMESH_TNodeXYZ( elem ));
1408 //=======================================================================
1410 * \brief Return minimal distance from a point to a face
1412 * Currently we ignore non-planarity and 2nd order of face
1414 //=======================================================================
1416 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshFace* face,
1417 const gp_Pnt& point )
1419 double badDistance = -1;
1420 if ( !face ) return badDistance;
1422 // coordinates of nodes (medium nodes, if any, ignored)
1423 typedef SMDS_StdIterator< SMESH_TNodeXYZ, SMDS_ElemIteratorPtr > TXyzIterator;
1424 vector<gp_XYZ> xyz( TXyzIterator( face->nodesIterator()), TXyzIterator() );
1425 xyz.resize( face->NbCornerNodes()+1 );
1427 // transformation to get xyz[0] lies on the origin, xyz[1] lies on the Z axis,
1428 // and xyz[2] lies in the XZ plane. This is to pass to 2D space on XZ plane.
1430 gp_Vec OZ ( xyz[0], xyz[1] );
1431 gp_Vec OX ( xyz[0], xyz[2] );
1432 if ( OZ.Magnitude() < std::numeric_limits<double>::min() )
1434 if ( xyz.size() < 4 ) return badDistance;
1435 OZ = gp_Vec ( xyz[0], xyz[2] );
1436 OX = gp_Vec ( xyz[0], xyz[3] );
1440 tgtCS = gp_Ax3( xyz[0], OZ, OX );
1442 catch ( Standard_Failure ) {
1445 trsf.SetTransformation( tgtCS );
1447 // move all the nodes to 2D
1448 vector<gp_XY> xy( xyz.size() );
1449 for ( size_t i = 0;i < xyz.size()-1; ++i )
1451 gp_XYZ p3d = xyz[i];
1452 trsf.Transforms( p3d );
1453 xy[i].SetCoord( p3d.X(), p3d.Z() );
1455 xyz.back() = xyz.front();
1456 xy.back() = xy.front();
1458 // // move the point in 2D
1459 gp_XYZ tmpPnt = point.XYZ();
1460 trsf.Transforms( tmpPnt );
1461 gp_XY point2D( tmpPnt.X(), tmpPnt.Z() );
1463 // loop on segments of the face to analyze point position ralative to the face
1464 set< PointPos > pntPosSet;
1465 for ( size_t i = 1; i < xy.size(); ++i )
1467 PointPos pos = getPointPosition( point2D, &xy[0], i-1 );
1468 pntPosSet.insert( pos );
1472 PointPos pos = *pntPosSet.begin();
1473 // cout << "Face " << face->GetID() << " DIST: ";
1474 switch ( pos._name )
1477 // point is most close to a segment
1478 gp_Vec p0p1( point, xyz[ pos._index ] );
1479 gp_Vec p1p2( xyz[ pos._index ], xyz[ pos._index+1 ]); // segment vector
1481 double projDist = p0p1 * p1p2; // distance projected to the segment
1482 gp_Vec projVec = p1p2 * projDist;
1483 gp_Vec distVec = p0p1 - projVec;
1484 // cout << distVec.Magnitude() << ", SEG " << face->GetNode(pos._index)->GetID()
1485 // << " - " << face->GetNodeWrap(pos._index+1)->GetID() << endl;
1486 return distVec.Magnitude();
1489 // point is inside the face
1490 double distToFacePlane = tmpPnt.Y();
1491 // cout << distToFacePlane << ", INSIDE " << endl;
1492 return Abs( distToFacePlane );
1495 // point is most close to a node
1496 gp_Vec distVec( point, xyz[ pos._index ]);
1497 // cout << distVec.Magnitude() << " VERTEX " << face->GetNode(pos._index)->GetID() << endl;
1498 return distVec.Magnitude();
1505 //=======================================================================
1507 * \brief Return minimal distance from a point to an edge
1509 //=======================================================================
1511 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshEdge* seg, const gp_Pnt& point )
1513 double dist = Precision::Infinite();
1514 if ( !seg ) return dist;
1516 int i = 0, nbNodes = seg->NbNodes();
1518 vector< SMESH_TNodeXYZ > xyz( nbNodes );
1519 SMDS_ElemIteratorPtr nodeIt = seg->interlacedNodesElemIterator();
1520 while ( nodeIt->more() )
1521 xyz[ i++ ].Set( nodeIt->next() );
1523 for ( i = 1; i < nbNodes; ++i )
1525 gp_Vec edge( xyz[i-1], xyz[i] );
1526 gp_Vec n1p ( xyz[i-1], point );
1527 double u = ( edge * n1p ) / edge.SquareMagnitude(); // param [0,1] on the edge
1529 dist = Min( dist, n1p.SquareMagnitude() );
1531 else if ( u >= 1. ) {
1532 dist = Min( dist, point.SquareDistance( xyz[i] ));
1535 gp_XYZ proj = ( 1. - u ) * xyz[i-1] + u * xyz[i]; // projection of the point on the edge
1536 dist = Min( dist, point.SquareDistance( proj ));
1539 return Sqrt( dist );
1542 //=======================================================================
1544 * \brief Return minimal distance from a point to a volume
1546 * Currently we ignore non-planarity and 2nd order
1548 //=======================================================================
1550 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshVolume* volume, const gp_Pnt& point )
1552 SMDS_VolumeTool vTool( volume );
1553 vTool.SetExternalNormal();
1554 const int iQ = volume->IsQuadratic() ? 2 : 1;
1557 double minDist = 1e100, dist;
1558 for ( int iF = 0; iF < vTool.NbFaces(); ++iF )
1560 // skip a facet with normal not "looking at" the point
1561 if ( !vTool.GetFaceNormal( iF, n[0], n[1], n[2] ) ||
1562 !vTool.GetFaceBaryCenter( iF, bc[0], bc[1], bc[2] ))
1564 gp_XYZ bcp = point.XYZ() - gp_XYZ( bc[0], bc[1], bc[2] );
1565 if ( gp_XYZ( n[0], n[1], n[2] ) * bcp < 1e-6 )
1568 // find distance to a facet
1569 const SMDS_MeshNode** nodes = vTool.GetFaceNodes( iF );
1570 switch ( vTool.NbFaceNodes( iF ) / iQ ) {
1573 SMDS_FaceOfNodes tmpFace( nodes[0], nodes[ 1*iQ ], nodes[ 2*iQ ] );
1574 dist = GetDistance( &tmpFace, point );
1579 SMDS_FaceOfNodes tmpFace( nodes[0], nodes[ 1*iQ ], nodes[ 2*iQ ], nodes[ 3*iQ ]);
1580 dist = GetDistance( &tmpFace, point );
1584 vector<const SMDS_MeshNode *> nvec( nodes, nodes + vTool.NbFaceNodes( iF ));
1585 SMDS_PolygonalFaceOfNodes tmpFace( nvec );
1586 dist = GetDistance( &tmpFace, point );
1588 minDist = Min( minDist, dist );
1593 //================================================================================
1595 * \brief Returns barycentric coordinates of a point within a triangle.
1596 * A not returned bc2 = 1. - bc0 - bc1.
1597 * The point lies within the triangle if ( bc0 >= 0 && bc1 >= 0 && bc0+bc1 <= 1 )
1599 //================================================================================
1601 void SMESH_MeshAlgos::GetBarycentricCoords( const gp_XY& p,
1608 const double // matrix 2x2
1609 T11 = t0.X()-t2.X(), T12 = t1.X()-t2.X(),
1610 T21 = t0.Y()-t2.Y(), T22 = t1.Y()-t2.Y();
1611 const double Tdet = T11*T22 - T12*T21; // matrix determinant
1612 if ( Abs( Tdet ) < std::numeric_limits<double>::min() )
1618 const double t11 = T22, t12 = -T12, t21 = -T21, t22 = T11;
1620 const double r11 = p.X()-t2.X(), r12 = p.Y()-t2.Y();
1621 // barycentric coordinates: mutiply matrix by vector
1622 bc0 = (t11 * r11 + t12 * r12)/Tdet;
1623 bc1 = (t21 * r11 + t22 * r12)/Tdet;
1626 //=======================================================================
1627 //function : FindFaceInSet
1628 //purpose : Return a face having linked nodes n1 and n2 and which is
1629 // - not in avoidSet,
1630 // - in elemSet provided that !elemSet.empty()
1631 // i1 and i2 optionally returns indices of n1 and n2
1632 //=======================================================================
1634 const SMDS_MeshElement*
1635 SMESH_MeshAlgos::FindFaceInSet(const SMDS_MeshNode* n1,
1636 const SMDS_MeshNode* n2,
1637 const TIDSortedElemSet& elemSet,
1638 const TIDSortedElemSet& avoidSet,
1644 const SMDS_MeshElement* face = 0;
1646 SMDS_ElemIteratorPtr invElemIt = n1->GetInverseElementIterator(SMDSAbs_Face);
1647 while ( invElemIt->more() && !face ) // loop on inverse faces of n1
1649 const SMDS_MeshElement* elem = invElemIt->next();
1650 if (avoidSet.count( elem ))
1652 if ( !elemSet.empty() && !elemSet.count( elem ))
1655 i1 = elem->GetNodeIndex( n1 );
1656 // find a n2 linked to n1
1657 int nbN = elem->IsQuadratic() ? elem->NbNodes()/2 : elem->NbNodes();
1658 for ( int di = -1; di < 2 && !face; di += 2 )
1660 i2 = (i1+di+nbN) % nbN;
1661 if ( elem->GetNode( i2 ) == n2 )
1664 if ( !face && elem->IsQuadratic())
1666 // analysis for quadratic elements using all nodes
1667 SMDS_ElemIteratorPtr anIter = elem->interlacedNodesElemIterator();
1668 const SMDS_MeshNode* prevN = static_cast<const SMDS_MeshNode*>( anIter->next() );
1669 for ( i1 = -1, i2 = 0; anIter->more() && !face; i1++, i2++ )
1671 const SMDS_MeshNode* n = static_cast<const SMDS_MeshNode*>( anIter->next() );
1672 if ( n1 == prevN && n2 == n )
1676 else if ( n2 == prevN && n1 == n )
1678 face = elem; swap( i1, i2 );
1684 if ( n1ind ) *n1ind = i1;
1685 if ( n2ind ) *n2ind = i2;
1689 //================================================================================
1691 * \brief Calculate normal of a mesh face
1693 //================================================================================
1695 bool SMESH_MeshAlgos::FaceNormal(const SMDS_MeshElement* F, gp_XYZ& normal, bool normalized)
1697 if ( !F || F->GetType() != SMDSAbs_Face )
1700 normal.SetCoord(0,0,0);
1701 int nbNodes = F->NbCornerNodes();
1702 for ( int i = 0; i < nbNodes-2; ++i )
1705 for ( int n = 0; n < 3; ++n )
1707 const SMDS_MeshNode* node = F->GetNode( i + n );
1708 p[n].SetCoord( node->X(), node->Y(), node->Z() );
1710 normal += ( p[2] - p[1] ) ^ ( p[0] - p[1] );
1712 double size2 = normal.SquareModulus();
1713 bool ok = ( size2 > numeric_limits<double>::min() * numeric_limits<double>::min());
1714 if ( normalized && ok )
1715 normal /= sqrt( size2 );
1720 //=======================================================================
1721 //function : GetCommonNodes
1722 //purpose : Return nodes common to two elements
1723 //=======================================================================
1725 vector< const SMDS_MeshNode*> SMESH_MeshAlgos::GetCommonNodes(const SMDS_MeshElement* e1,
1726 const SMDS_MeshElement* e2)
1728 vector< const SMDS_MeshNode*> common;
1729 for ( int i = 0 ; i < e1->NbNodes(); ++i )
1730 if ( e2->GetNodeIndex( e1->GetNode( i )) >= 0 )
1731 common.push_back( e1->GetNode( i ));
1735 //=======================================================================
1737 * \brief Return SMESH_NodeSearcher
1739 //=======================================================================
1741 SMESH_NodeSearcher* SMESH_MeshAlgos::GetNodeSearcher(SMDS_Mesh& mesh)
1743 return new SMESH_NodeSearcherImpl( &mesh );
1746 //=======================================================================
1748 * \brief Return SMESH_NodeSearcher
1750 //=======================================================================
1752 SMESH_NodeSearcher* SMESH_MeshAlgos::GetNodeSearcher(SMDS_ElemIteratorPtr elemIt)
1754 return new SMESH_NodeSearcherImpl( 0, elemIt );
1757 //=======================================================================
1759 * \brief Return SMESH_ElementSearcher
1761 //=======================================================================
1763 SMESH_ElementSearcher* SMESH_MeshAlgos::GetElementSearcher(SMDS_Mesh& mesh,
1766 return new SMESH_ElementSearcherImpl( mesh, tolerance );
1769 //=======================================================================
1771 * \brief Return SMESH_ElementSearcher acting on a sub-set of elements
1773 //=======================================================================
1775 SMESH_ElementSearcher* SMESH_MeshAlgos::GetElementSearcher(SMDS_Mesh& mesh,
1776 SMDS_ElemIteratorPtr elemIt,
1779 return new SMESH_ElementSearcherImpl( mesh, tolerance, elemIt );