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 prepare(); // !!!call it before calling the following methods!!!
232 void getElementsNearPoint( const gp_Pnt& point, vector<const SMDS_MeshElement*>& foundElems );
233 void getElementsNearLine ( const gp_Ax1& line, vector<const SMDS_MeshElement*>& foundElems);
234 void getElementsInSphere ( const gp_XYZ& center,
236 vector<const SMDS_MeshElement*>& foundElems);
239 ElementBndBoxTree() {}
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;
249 void init(const SMDS_MeshElement* elem, double tolerance);
251 vector< ElementBox* > _elements;
253 typedef ObjectPool< ElementBox > TElementBoxPool;
255 //!< allocator of ElementBox's and SMESH_TreeLimit
256 struct LimitAndPool : public SMESH_TreeLimit
258 TElementBoxPool _elBoPool;
259 std::vector< ElementBox* > _markedElems;
260 LimitAndPool():SMESH_TreeLimit( MaxLevel, /*minSize=*/0. ) {}
262 LimitAndPool* getLimitAndPool() const
264 SMESH_TreeLimit* limitAndPool = const_cast< SMESH_TreeLimit* >( myLimit );
265 return static_cast< LimitAndPool* >( limitAndPool );
269 //================================================================================
271 * \brief ElementBndBoxTree creation
273 //================================================================================
275 ElementBndBoxTree::ElementBndBoxTree(const SMDS_Mesh& mesh,
276 SMDSAbs_ElementType elemType,
277 SMDS_ElemIteratorPtr theElemIt,
279 :SMESH_Octree( new LimitAndPool() )
281 int nbElems = mesh.GetMeshInfo().NbElements( elemType );
282 _elements.reserve( nbElems );
284 TElementBoxPool& elBoPool = getLimitAndPool()->_elBoPool;
286 SMDS_ElemIteratorPtr elemIt = theElemIt ? theElemIt : mesh.elementsIterator( elemType );
287 while ( elemIt->more() )
289 ElementBox* eb = elBoPool.getNew();
290 eb->init( elemIt->next(), tolerance );
291 _elements.push_back( eb );
296 //================================================================================
298 * \brief Return the maximal box
300 //================================================================================
302 Bnd_B3d* ElementBndBoxTree::buildRootBox()
304 Bnd_B3d* box = new Bnd_B3d;
305 for ( size_t i = 0; i < _elements.size(); ++i )
306 box->Add( *_elements[i] );
310 //================================================================================
312 * \brief Redistrubute element boxes among children
314 //================================================================================
316 void ElementBndBoxTree::buildChildrenData()
318 for ( size_t i = 0; i < _elements.size(); ++i )
320 for (int j = 0; j < 8; j++)
322 if ( !_elements[i]->IsOut( *myChildren[j]->getBox() ))
323 ((ElementBndBoxTree*)myChildren[j])->_elements.push_back( _elements[i]);
326 //_size = _elements.size();
327 SMESHUtils::FreeVector( _elements ); // = _elements.clear() + free memory
329 for (int j = 0; j < 8; j++)
331 ElementBndBoxTree* child = static_cast<ElementBndBoxTree*>( myChildren[j]);
332 if ((int) child->_elements.size() <= MaxNbElemsInLeaf )
333 child->myIsLeaf = true;
335 if ( child->isLeaf() && child->_elements.capacity() > child->_elements.size() )
336 SMESHUtils::CompactVector( child->_elements );
340 //================================================================================
342 * \brief Un-mark all elements
344 //================================================================================
346 void ElementBndBoxTree::prepare()
348 // TElementBoxPool& elBoPool = getElementBoxPool();
349 // for ( size_t i = 0; i < elBoPool.nbElements(); ++i )
350 // const_cast< ElementBox* >( elBoPool[ i ])->_isMarked = false;
353 //================================================================================
355 * \brief Return elements which can include the point
357 //================================================================================
359 void ElementBndBoxTree::getElementsNearPoint( const gp_Pnt& point,
360 vector<const SMDS_MeshElement*>& foundElems)
362 if ( getBox()->IsOut( point.XYZ() ))
367 LimitAndPool* pool = getLimitAndPool();
369 for ( size_t i = 0; i < _elements.size(); ++i )
370 if ( !_elements[i]->IsOut( point.XYZ() ) &&
371 !_elements[i]->_isMarked )
373 foundElems.push_back( _elements[i]->_element );
374 _elements[i]->_isMarked = true;
375 pool->_markedElems.push_back( _elements[i] );
380 for (int i = 0; i < 8; i++)
381 ((ElementBndBoxTree*) myChildren[i])->getElementsNearPoint( point, foundElems );
385 LimitAndPool* pool = getLimitAndPool();
386 for ( size_t i = 0; i < pool->_markedElems.size(); ++i )
387 pool->_markedElems[i]->_isMarked = false;
388 pool->_markedElems.clear();
393 //================================================================================
395 * \brief Return elements which can be intersected by the line
397 //================================================================================
399 void ElementBndBoxTree::getElementsNearLine( const gp_Ax1& line,
400 vector<const SMDS_MeshElement*>& foundElems)
402 if ( getBox()->IsOut( line ))
407 LimitAndPool* pool = getLimitAndPool();
409 for ( size_t i = 0; i < _elements.size(); ++i )
410 if ( !_elements[i]->IsOut( line ) &&
411 !_elements[i]->_isMarked )
413 foundElems.push_back( _elements[i]->_element );
414 _elements[i]->_isMarked = true;
415 pool->_markedElems.push_back( _elements[i] );
420 for (int i = 0; i < 8; i++)
421 ((ElementBndBoxTree*) myChildren[i])->getElementsNearLine( line, foundElems );
425 LimitAndPool* pool = getLimitAndPool();
426 for ( size_t i = 0; i < pool->_markedElems.size(); ++i )
427 pool->_markedElems[i]->_isMarked = false;
428 pool->_markedElems.clear();
433 //================================================================================
435 * \brief Return elements from leaves intersecting the sphere
437 //================================================================================
439 void ElementBndBoxTree::getElementsInSphere ( const gp_XYZ& center,
441 vector<const SMDS_MeshElement*>& foundElems)
443 if ( getBox()->IsOut( center, radius ))
448 LimitAndPool* pool = getLimitAndPool();
450 for ( size_t i = 0; i < _elements.size(); ++i )
451 if ( !_elements[i]->IsOut( center, radius ) &&
452 !_elements[i]->_isMarked )
454 foundElems.push_back( _elements[i]->_element );
455 _elements[i]->_isMarked = true;
456 pool->_markedElems.push_back( _elements[i] );
461 for (int i = 0; i < 8; i++)
462 ((ElementBndBoxTree*) myChildren[i])->getElementsInSphere( center, radius, foundElems );
466 LimitAndPool* pool = getLimitAndPool();
467 for ( size_t i = 0; i < pool->_markedElems.size(); ++i )
468 pool->_markedElems[i]->_isMarked = false;
469 pool->_markedElems.clear();
474 //================================================================================
476 * \brief Construct the element box
478 //================================================================================
480 void ElementBndBoxTree::ElementBox::init(const SMDS_MeshElement* elem, double tolerance)
484 SMDS_ElemIteratorPtr nIt = elem->nodesIterator();
485 while ( nIt->more() )
486 Add( SMESH_NodeXYZ( nIt->next() ));
487 Enlarge( tolerance );
492 //=======================================================================
494 * \brief Implementation of search for the elements by point and
495 * of classification of point in 2D mesh
497 //=======================================================================
499 SMESH_ElementSearcher::~SMESH_ElementSearcher()
503 struct SMESH_ElementSearcherImpl: public SMESH_ElementSearcher
506 SMDS_ElemIteratorPtr _meshPartIt;
507 ElementBndBoxTree* _ebbTree [SMDSAbs_NbElementTypes];
508 int _ebbTreeHeight[SMDSAbs_NbElementTypes];
509 SMESH_NodeSearcherImpl* _nodeSearcher;
510 SMDSAbs_ElementType _elementType;
512 bool _outerFacesFound;
513 set<const SMDS_MeshElement*> _outerFaces; // empty means "no internal faces at all"
515 SMESH_ElementSearcherImpl( SMDS_Mesh& mesh,
517 SMDS_ElemIteratorPtr elemIt=SMDS_ElemIteratorPtr())
518 : _mesh(&mesh),_meshPartIt(elemIt),_nodeSearcher(0),_tolerance(tol),_outerFacesFound(false)
520 for ( int i = 0; i < SMDSAbs_NbElementTypes; ++i )
523 _ebbTreeHeight[i] = -1;
525 _elementType = SMDSAbs_All;
527 virtual ~SMESH_ElementSearcherImpl()
529 for ( int i = 0; i < SMDSAbs_NbElementTypes; ++i )
531 delete _ebbTree[i]; _ebbTree[i] = NULL;
533 if ( _nodeSearcher ) delete _nodeSearcher; _nodeSearcher = 0;
535 virtual int FindElementsByPoint(const gp_Pnt& point,
536 SMDSAbs_ElementType type,
537 vector< const SMDS_MeshElement* >& foundElements);
538 virtual TopAbs_State GetPointState(const gp_Pnt& point);
539 virtual const SMDS_MeshElement* FindClosestTo( const gp_Pnt& point,
540 SMDSAbs_ElementType type );
542 void GetElementsNearLine( const gp_Ax1& line,
543 SMDSAbs_ElementType type,
544 vector< const SMDS_MeshElement* >& foundElems);
545 void GetElementsInSphere( const gp_XYZ& center,
547 SMDSAbs_ElementType type,
548 vector< const SMDS_MeshElement* >& foundElems);
549 double getTolerance();
550 bool getIntersParamOnLine(const gp_Lin& line, const SMDS_MeshElement* face,
551 const double tolerance, double & param);
552 void findOuterBoundary(const SMDS_MeshElement* anyOuterFace);
553 bool isOuterBoundary(const SMDS_MeshElement* face) const
555 return _outerFaces.empty() || _outerFaces.count(face);
559 if ( _ebbTreeHeight[ _elementType ] < 0 )
560 _ebbTreeHeight[ _elementType ] = _ebbTree[ _elementType ]->getHeight();
561 return _ebbTreeHeight[ _elementType ];
564 struct TInters //!< data of intersection of the line and the mesh face (used in GetPointState())
566 const SMDS_MeshElement* _face;
568 bool _coincides; //!< the line lays in face plane
569 TInters(const SMDS_MeshElement* face, const gp_Vec& faceNorm, bool coinc=false)
570 : _face(face), _faceNorm( faceNorm ), _coincides( coinc ) {}
572 struct TFaceLink //!< link and faces sharing it (used in findOuterBoundary())
575 TIDSortedElemSet _faces;
576 TFaceLink( const SMDS_MeshNode* n1, const SMDS_MeshNode* n2, const SMDS_MeshElement* face)
577 : _link( n1, n2 ), _faces( &face, &face + 1) {}
581 ostream& operator<< (ostream& out, const SMESH_ElementSearcherImpl::TInters& i)
583 return out << "TInters(face=" << ( i._face ? i._face->GetID() : 0)
584 << ", _coincides="<<i._coincides << ")";
587 //=======================================================================
589 * \brief define tolerance for search
591 //=======================================================================
593 double SMESH_ElementSearcherImpl::getTolerance()
595 if ( _tolerance < 0 )
597 const SMDS_MeshInfo& meshInfo = _mesh->GetMeshInfo();
600 if ( _nodeSearcher && meshInfo.NbNodes() > 1 )
602 double boxSize = _nodeSearcher->getTree()->maxSize();
603 _tolerance = 1e-8 * boxSize/* / meshInfo.NbNodes()*/;
605 else if ( _ebbTree[_elementType] && meshInfo.NbElements() > 0 )
607 double boxSize = _ebbTree[_elementType]->maxSize();
608 _tolerance = 1e-8 * boxSize/* / meshInfo.NbElements()*/;
610 if ( _tolerance == 0 )
612 // define tolerance by size of a most complex element
613 int complexType = SMDSAbs_Volume;
614 while ( complexType > SMDSAbs_All &&
615 meshInfo.NbElements( SMDSAbs_ElementType( complexType )) < 1 )
617 if ( complexType == SMDSAbs_All ) return 0; // empty mesh
619 if ( complexType == int( SMDSAbs_Node ))
621 SMDS_NodeIteratorPtr nodeIt = _mesh->nodesIterator();
623 if ( meshInfo.NbNodes() > 2 )
624 elemSize = SMESH_TNodeXYZ( nodeIt->next() ).Distance( nodeIt->next() );
628 SMDS_ElemIteratorPtr elemIt = _mesh->elementsIterator( SMDSAbs_ElementType( complexType ));
629 const SMDS_MeshElement* elem = elemIt->next();
630 SMDS_ElemIteratorPtr nodeIt = elem->nodesIterator();
631 SMESH_TNodeXYZ n1( nodeIt->next() );
633 while ( nodeIt->more() )
635 double dist = n1.Distance( static_cast<const SMDS_MeshNode*>( nodeIt->next() ));
636 elemSize = max( dist, elemSize );
639 _tolerance = 1e-4 * elemSize;
645 //================================================================================
647 * \brief Find intersection of the line and an edge of face and return parameter on line
649 //================================================================================
651 bool SMESH_ElementSearcherImpl::getIntersParamOnLine(const gp_Lin& line,
652 const SMDS_MeshElement* face,
659 GeomAPI_ExtremaCurveCurve anExtCC;
660 Handle(Geom_Curve) lineCurve = new Geom_Line( line );
662 int nbNodes = face->IsQuadratic() ? face->NbNodes()/2 : face->NbNodes();
663 for ( int i = 0; i < nbNodes && nbInts < 2; ++i )
665 GC_MakeSegment edge( SMESH_TNodeXYZ( face->GetNode( i )),
666 SMESH_TNodeXYZ( face->GetNode( (i+1)%nbNodes) ));
667 anExtCC.Init( lineCurve, edge.Value() );
668 if ( anExtCC.NbExtrema() > 0 && anExtCC.LowerDistance() <= tol)
670 Standard_Real pl, pe;
671 anExtCC.LowerDistanceParameters( pl, pe );
677 if ( nbInts > 0 ) param /= nbInts;
680 //================================================================================
682 * \brief Find all faces belonging to the outer boundary of mesh
684 //================================================================================
686 void SMESH_ElementSearcherImpl::findOuterBoundary(const SMDS_MeshElement* outerFace)
688 if ( _outerFacesFound ) return;
690 // Collect all outer faces by passing from one outer face to another via their links
691 // and BTW find out if there are internal faces at all.
693 // checked links and links where outer boundary meets internal one
694 set< SMESH_TLink > visitedLinks, seamLinks;
696 // links to treat with already visited faces sharing them
697 list < TFaceLink > startLinks;
699 // load startLinks with the first outerFace
700 startLinks.push_back( TFaceLink( outerFace->GetNode(0), outerFace->GetNode(1), outerFace));
701 _outerFaces.insert( outerFace );
703 TIDSortedElemSet emptySet;
704 while ( !startLinks.empty() )
706 const SMESH_TLink& link = startLinks.front()._link;
707 TIDSortedElemSet& faces = startLinks.front()._faces;
709 outerFace = *faces.begin();
710 // find other faces sharing the link
711 const SMDS_MeshElement* f;
712 while (( f = SMESH_MeshAlgos::FindFaceInSet(link.node1(), link.node2(), emptySet, faces )))
715 // select another outer face among the found
716 const SMDS_MeshElement* outerFace2 = 0;
717 if ( faces.size() == 2 )
719 outerFace2 = (outerFace == *faces.begin() ? *faces.rbegin() : *faces.begin());
721 else if ( faces.size() > 2 )
723 seamLinks.insert( link );
725 // link direction within the outerFace
726 gp_Vec n1n2( SMESH_TNodeXYZ( link.node1()),
727 SMESH_TNodeXYZ( link.node2()));
728 int i1 = outerFace->GetNodeIndex( link.node1() );
729 int i2 = outerFace->GetNodeIndex( link.node2() );
730 bool rev = ( abs(i2-i1) == 1 ? i1 > i2 : i2 > i1 );
731 if ( rev ) n1n2.Reverse();
733 gp_XYZ ofNorm, fNorm;
734 if ( SMESH_MeshAlgos::FaceNormal( outerFace, ofNorm, /*normalized=*/false ))
736 // direction from the link inside outerFace
737 gp_Vec dirInOF = gp_Vec( ofNorm ) ^ n1n2;
738 // sort all other faces by angle with the dirInOF
739 map< double, const SMDS_MeshElement* > angle2Face;
740 set< const SMDS_MeshElement*, TIDCompare >::const_iterator face = faces.begin();
741 for ( ; face != faces.end(); ++face )
743 if ( *face == outerFace ) continue;
744 if ( !SMESH_MeshAlgos::FaceNormal( *face, fNorm, /*normalized=*/false ))
746 gp_Vec dirInF = gp_Vec( fNorm ) ^ n1n2;
747 double angle = dirInOF.AngleWithRef( dirInF, n1n2 );
748 if ( angle < 0 ) angle += 2. * M_PI;
749 angle2Face.insert( make_pair( angle, *face ));
751 if ( !angle2Face.empty() )
752 outerFace2 = angle2Face.begin()->second;
755 // store the found outer face and add its links to continue searching from
758 _outerFaces.insert( outerFace2 );
759 int nbNodes = outerFace2->NbCornerNodes();
760 for ( int i = 0; i < nbNodes; ++i )
762 SMESH_TLink link2( outerFace2->GetNode(i), outerFace2->GetNode((i+1)%nbNodes));
763 if ( visitedLinks.insert( link2 ).second )
764 startLinks.push_back( TFaceLink( link2.node1(), link2.node2(), outerFace2 ));
767 startLinks.pop_front();
769 _outerFacesFound = true;
771 if ( !seamLinks.empty() )
773 // There are internal boundaries touching the outher one,
774 // find all faces of internal boundaries in order to find
775 // faces of boundaries of holes, if any.
784 //=======================================================================
786 * \brief Find elements of given type where the given point is IN or ON.
787 * Returns nb of found elements and elements them-selves.
789 * 'ALL' type means elements of any type excluding nodes, balls and 0D elements
791 //=======================================================================
793 int SMESH_ElementSearcherImpl::
794 FindElementsByPoint(const gp_Pnt& point,
795 SMDSAbs_ElementType type,
796 vector< const SMDS_MeshElement* >& foundElements)
798 foundElements.clear();
801 double tolerance = getTolerance();
803 // =================================================================================
804 if ( type == SMDSAbs_Node || type == SMDSAbs_0DElement || type == SMDSAbs_Ball)
806 if ( !_nodeSearcher )
809 _nodeSearcher = new SMESH_NodeSearcherImpl( 0, _meshPartIt );
811 _nodeSearcher = new SMESH_NodeSearcherImpl( _mesh );
813 std::vector< const SMDS_MeshNode* > foundNodes;
814 _nodeSearcher->FindNearPoint( point, tolerance, foundNodes );
816 if ( type == SMDSAbs_Node )
818 foundElements.assign( foundNodes.begin(), foundNodes.end() );
822 for ( size_t i = 0; i < foundNodes.size(); ++i )
824 SMDS_ElemIteratorPtr elemIt = foundNodes[i]->GetInverseElementIterator( type );
825 while ( elemIt->more() )
826 foundElements.push_back( elemIt->next() );
830 // =================================================================================
831 else // elements more complex than 0D
833 if ( !_ebbTree[type] )
835 _ebbTree[_elementType] = new ElementBndBoxTree( *_mesh, type, _meshPartIt, tolerance );
839 _ebbTree[ type ]->prepare();
841 vector< const SMDS_MeshElement* > suspectElems;
842 _ebbTree[ type ]->getElementsNearPoint( point, suspectElems );
843 vector< const SMDS_MeshElement* >::iterator elem = suspectElems.begin();
844 for ( ; elem != suspectElems.end(); ++elem )
845 if ( !SMESH_MeshAlgos::IsOut( *elem, point, tolerance ))
846 foundElements.push_back( *elem );
848 return foundElements.size();
851 //=======================================================================
853 * \brief Find an element of given type most close to the given point
855 * WARNING: Only face search is implemeneted so far
857 //=======================================================================
859 const SMDS_MeshElement*
860 SMESH_ElementSearcherImpl::FindClosestTo( const gp_Pnt& point,
861 SMDSAbs_ElementType type )
863 const SMDS_MeshElement* closestElem = 0;
866 if ( type == SMDSAbs_Face || type == SMDSAbs_Volume )
868 ElementBndBoxTree*& ebbTree = _ebbTree[ type ];
870 ebbTree = new ElementBndBoxTree( *_mesh, type, _meshPartIt );
874 vector<const SMDS_MeshElement*> suspectElems;
875 ebbTree->getElementsNearPoint( point, suspectElems );
877 if ( suspectElems.empty() && ebbTree->maxSize() > 0 )
879 gp_Pnt boxCenter = 0.5 * ( ebbTree->getBox()->CornerMin() +
880 ebbTree->getBox()->CornerMax() );
882 if ( ebbTree->getBox()->IsOut( point.XYZ() ))
883 radius = point.Distance( boxCenter ) - 0.5 * ebbTree->maxSize();
885 radius = ebbTree->maxSize() / pow( 2., getTreeHeight()) / 2;
886 while ( suspectElems.empty() )
889 ebbTree->getElementsInSphere( point.XYZ(), radius, suspectElems );
893 double minDist = std::numeric_limits<double>::max();
894 multimap< double, const SMDS_MeshElement* > dist2face;
895 vector<const SMDS_MeshElement*>::iterator elem = suspectElems.begin();
896 for ( ; elem != suspectElems.end(); ++elem )
898 double dist = SMESH_MeshAlgos::GetDistance( *elem, point );
899 if ( dist < minDist + 1e-10)
902 dist2face.insert( dist2face.begin(), make_pair( dist, *elem ));
905 if ( !dist2face.empty() )
907 multimap< double, const SMDS_MeshElement* >::iterator d2f = dist2face.begin();
908 closestElem = d2f->second;
909 // if there are several elements at the same distance, select one
910 // with GC closest to the point
911 typedef SMDS_StdIterator< SMESH_TNodeXYZ, SMDS_ElemIteratorPtr > TXyzIterator;
912 double minDistToGC = 0;
913 for ( ++d2f; d2f != dist2face.end() && fabs( d2f->first - minDist ) < 1e-10; ++d2f )
915 if ( minDistToGC == 0 )
918 gc = accumulate( TXyzIterator(closestElem->nodesIterator()),
919 TXyzIterator(), gc ) / closestElem->NbNodes();
920 minDistToGC = point.SquareDistance( gc );
923 gc = accumulate( TXyzIterator( d2f->second->nodesIterator()),
924 TXyzIterator(), gc ) / d2f->second->NbNodes();
925 double d = point.SquareDistance( gc );
926 if ( d < minDistToGC )
929 closestElem = d2f->second;
932 // cout << "FindClosestTo( " <<point.X()<<", "<<point.Y()<<", "<<point.Z()<<" ) FACE "
933 // <<closestElem->GetID() << " DIST " << minDist << endl;
938 // NOT IMPLEMENTED SO FAR
944 //================================================================================
946 * \brief Classify the given point in the closed 2D mesh
948 //================================================================================
950 TopAbs_State SMESH_ElementSearcherImpl::GetPointState(const gp_Pnt& point)
952 _elementType = SMDSAbs_Face;
954 double tolerance = getTolerance();
956 ElementBndBoxTree*& ebbTree = _ebbTree[ SMDSAbs_Face ];
958 ebbTree = new ElementBndBoxTree( *_mesh, _elementType, _meshPartIt );
962 // Algo: analyse transition of a line starting at the point through mesh boundary;
963 // try three lines parallel to axis of the coordinate system and perform rough
964 // analysis. If solution is not clear perform thorough analysis.
966 const int nbAxes = 3;
967 gp_Dir axisDir[ nbAxes ] = { gp::DX(), gp::DY(), gp::DZ() };
968 map< double, TInters > paramOnLine2TInters[ nbAxes ];
969 list< TInters > tangentInters[ nbAxes ]; // of faces whose plane includes the line
970 multimap< int, int > nbInt2Axis; // to find the simplest case
971 for ( int axis = 0; axis < nbAxes; ++axis )
973 gp_Ax1 lineAxis( point, axisDir[axis]);
974 gp_Lin line ( lineAxis );
976 vector<const SMDS_MeshElement*> suspectFaces; // faces possibly intersecting the line
977 if ( axis > 0 ) ebbTree->prepare();
978 ebbTree->getElementsNearLine( lineAxis, suspectFaces );
980 // Intersect faces with the line
982 map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
983 vector<const SMDS_MeshElement*>::iterator face = suspectFaces.begin();
984 for ( ; face != suspectFaces.end(); ++face )
988 if ( !SMESH_MeshAlgos::FaceNormal( *face, fNorm, /*normalized=*/false)) continue;
989 gp_Pln facePlane( SMESH_TNodeXYZ( (*face)->GetNode(0)), fNorm );
991 // perform intersection
992 IntAna_IntConicQuad intersection( line, IntAna_Quadric( facePlane ));
993 if ( !intersection.IsDone() )
995 if ( intersection.IsInQuadric() )
997 tangentInters[ axis ].push_back( TInters( *face, fNorm, true ));
999 else if ( ! intersection.IsParallel() && intersection.NbPoints() > 0 )
1001 double tol = 1e-4 * Sqrt( fNorm.Modulus() );
1002 gp_Pnt intersectionPoint = intersection.Point(1);
1003 if ( !SMESH_MeshAlgos::IsOut( *face, intersectionPoint, tol ))
1004 u2inters.insert(make_pair( intersection.ParamOnConic(1), TInters( *face, fNorm )));
1007 // Analyse intersections roughly
1009 int nbInter = u2inters.size();
1013 double f = u2inters.begin()->first, l = u2inters.rbegin()->first;
1014 if ( nbInter == 1 ) // not closed mesh
1015 return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
1017 if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
1020 if ( (f<0) == (l<0) )
1023 int nbIntBeforePoint = std::distance( u2inters.begin(), u2inters.lower_bound(0));
1024 int nbIntAfterPoint = nbInter - nbIntBeforePoint;
1025 if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
1028 nbInt2Axis.insert( make_pair( min( nbIntBeforePoint, nbIntAfterPoint ), axis ));
1030 if ( _outerFacesFound ) break; // pass to thorough analysis
1032 } // three attempts - loop on CS axes
1034 // Analyse intersections thoroughly.
1035 // We make two loops maximum, on the first one we only exclude touching intersections,
1036 // on the second, if situation is still unclear, we gather and use information on
1037 // position of faces (internal or outer). If faces position is already gathered,
1038 // we make the second loop right away.
1040 for ( int hasPositionInfo = _outerFacesFound; hasPositionInfo < 2; ++hasPositionInfo )
1042 multimap< int, int >::const_iterator nb_axis = nbInt2Axis.begin();
1043 for ( ; nb_axis != nbInt2Axis.end(); ++nb_axis )
1045 int axis = nb_axis->second;
1046 map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
1048 gp_Ax1 lineAxis( point, axisDir[axis]);
1049 gp_Lin line ( lineAxis );
1051 // add tangent intersections to u2inters
1053 list< TInters >::const_iterator tgtInt = tangentInters[ axis ].begin();
1054 for ( ; tgtInt != tangentInters[ axis ].end(); ++tgtInt )
1055 if ( getIntersParamOnLine( line, tgtInt->_face, tolerance, param ))
1056 u2inters.insert(make_pair( param, *tgtInt ));
1057 tangentInters[ axis ].clear();
1059 // Count intersections before and after the point excluding touching ones.
1060 // If hasPositionInfo we count intersections of outer boundary only
1062 int nbIntBeforePoint = 0, nbIntAfterPoint = 0;
1063 double f = numeric_limits<double>::max(), l = -numeric_limits<double>::max();
1064 map< double, TInters >::iterator u_int1 = u2inters.begin(), u_int2 = u_int1;
1065 bool ok = ! u_int1->second._coincides;
1066 while ( ok && u_int1 != u2inters.end() )
1068 double u = u_int1->first;
1069 bool touchingInt = false;
1070 if ( ++u_int2 != u2inters.end() )
1072 // skip intersections at the same point (if the line passes through edge or node)
1074 while ( u_int2 != u2inters.end() && fabs( u_int2->first - u ) < tolerance )
1080 // skip tangent intersections
1082 if ( u_int2 != u2inters.end() )
1084 const SMDS_MeshElement* prevFace = u_int1->second._face;
1085 while ( ok && u_int2->second._coincides )
1087 if ( SMESH_MeshAlgos::GetCommonNodes(prevFace , u_int2->second._face).empty() )
1093 ok = ( u_int2 != u2inters.end() );
1099 // skip intersections at the same point after tangent intersections
1102 double u2 = u_int2->first;
1104 while ( u_int2 != u2inters.end() && fabs( u_int2->first - u2 ) < tolerance )
1110 // decide if we skipped a touching intersection
1111 if ( nbSamePnt + nbTgt > 0 )
1113 double minDot = numeric_limits<double>::max(), maxDot = -numeric_limits<double>::max();
1114 map< double, TInters >::iterator u_int = u_int1;
1115 for ( ; u_int != u_int2; ++u_int )
1117 if ( u_int->second._coincides ) continue;
1118 double dot = u_int->second._faceNorm * line.Direction();
1119 if ( dot > maxDot ) maxDot = dot;
1120 if ( dot < minDot ) minDot = dot;
1122 touchingInt = ( minDot*maxDot < 0 );
1127 if ( !hasPositionInfo || isOuterBoundary( u_int1->second._face ))
1138 u_int1 = u_int2; // to next intersection
1140 } // loop on intersections with one line
1144 if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
1147 if ( nbIntBeforePoint == 0 || nbIntAfterPoint == 0)
1150 if ( nbIntBeforePoint + nbIntAfterPoint == 1 ) // not closed mesh
1151 return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
1153 if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
1156 if ( (f<0) == (l<0) )
1159 if ( hasPositionInfo )
1160 return nbIntBeforePoint % 2 ? TopAbs_IN : TopAbs_OUT;
1162 } // loop on intersections of the tree lines - thorough analysis
1164 if ( !hasPositionInfo )
1166 // gather info on faces position - is face in the outer boundary or not
1167 map< double, TInters > & u2inters = paramOnLine2TInters[ 0 ];
1168 findOuterBoundary( u2inters.begin()->second._face );
1171 } // two attempts - with and w/o faces position info in the mesh
1173 return TopAbs_UNKNOWN;
1176 //=======================================================================
1178 * \brief Return elements possibly intersecting the line
1180 //=======================================================================
1182 void SMESH_ElementSearcherImpl::GetElementsNearLine( const gp_Ax1& line,
1183 SMDSAbs_ElementType type,
1184 vector< const SMDS_MeshElement* >& foundElems)
1186 _elementType = type;
1187 ElementBndBoxTree*& ebbTree = _ebbTree[ type ];
1189 ebbTree = new ElementBndBoxTree( *_mesh, _elementType, _meshPartIt );
1193 ebbTree->getElementsNearLine( line, foundElems );
1196 //=======================================================================
1198 * Return elements whose bounding box intersects a sphere
1200 //=======================================================================
1202 void SMESH_ElementSearcherImpl::GetElementsInSphere( const gp_XYZ& center,
1203 const double radius,
1204 SMDSAbs_ElementType type,
1205 vector< const SMDS_MeshElement* >& foundElems)
1207 _elementType = type;
1208 ElementBndBoxTree*& ebbTree = _ebbTree[ type ];
1210 ebbTree = new ElementBndBoxTree( *_mesh, _elementType, _meshPartIt );
1214 ebbTree->getElementsInSphere( center, radius, foundElems );
1217 //=======================================================================
1219 * \brief Return true if the point is IN or ON of the element
1221 //=======================================================================
1223 bool SMESH_MeshAlgos::IsOut( const SMDS_MeshElement* element, const gp_Pnt& point, double tol )
1225 if ( element->GetType() == SMDSAbs_Volume)
1227 return SMDS_VolumeTool( element ).IsOut( point.X(), point.Y(), point.Z(), tol );
1230 // get ordered nodes
1232 vector< SMESH_TNodeXYZ > xyz; xyz.reserve( element->NbNodes()+1 );
1234 SMDS_ElemIteratorPtr nodeIt = element->interlacedNodesElemIterator();
1235 for ( int i = 0; nodeIt->more(); ++i )
1236 xyz.push_back( SMESH_TNodeXYZ( nodeIt->next() ));
1238 int i, nbNodes = (int) xyz.size(); // central node of biquadratic is missing
1240 if ( element->GetType() == SMDSAbs_Face ) // --------------------------------------------------
1242 // compute face normal
1243 gp_Vec faceNorm(0,0,0);
1244 xyz.push_back( xyz.front() );
1245 for ( i = 0; i < nbNodes; ++i )
1247 gp_Vec edge1( xyz[i+1], xyz[i]);
1248 gp_Vec edge2( xyz[i+1], xyz[(i+2)%nbNodes] );
1249 faceNorm += edge1 ^ edge2;
1251 double fNormSize = faceNorm.Magnitude();
1252 if ( fNormSize <= tol )
1254 // degenerated face: point is out if it is out of all face edges
1255 for ( i = 0; i < nbNodes; ++i )
1257 SMDS_LinearEdge edge( xyz[i]._node, xyz[i+1]._node );
1258 if ( !IsOut( &edge, point, tol ))
1263 faceNorm /= fNormSize;
1265 // check if the point lays on face plane
1266 gp_Vec n2p( xyz[0], point );
1267 double dot = n2p * faceNorm;
1268 if ( Abs( dot ) > tol ) // not on face plane
1271 if ( nbNodes > 3 ) // maybe the face is not planar
1273 double elemThick = 0;
1274 for ( i = 1; i < nbNodes; ++i )
1276 gp_Vec n2n( xyz[0], xyz[i] );
1277 elemThick = Max( elemThick, Abs( n2n * faceNorm ));
1279 isOut = Abs( dot ) > elemThick + tol;
1285 // check if point is out of face boundary:
1286 // define it by closest transition of a ray point->infinity through face boundary
1287 // on the face plane.
1288 // First, find normal of a plane perpendicular to face plane, to be used as a cutting tool
1289 // to find intersections of the ray with the boundary.
1291 gp_Vec plnNorm = ray ^ faceNorm;
1292 double n2pSize = plnNorm.Magnitude();
1293 if ( n2pSize <= tol ) return false; // point coincides with the first node
1294 if ( n2pSize * n2pSize > fNormSize * 100 ) return true; // point is very far
1296 // for each node of the face, compute its signed distance to the cutting plane
1297 vector<double> dist( nbNodes + 1);
1298 for ( i = 0; i < nbNodes; ++i )
1300 gp_Vec n2p( xyz[i], point );
1301 dist[i] = n2p * plnNorm;
1303 dist.back() = dist.front();
1304 // find the closest intersection
1306 double rClosest = 0, distClosest = 1e100;
1308 for ( i = 0; i < nbNodes; ++i )
1311 if ( fabs( dist[i] ) < tol )
1313 else if ( fabs( dist[i+1]) < tol )
1315 else if ( dist[i] * dist[i+1] < 0 )
1316 r = dist[i] / ( dist[i] - dist[i+1] );
1318 continue; // no intersection
1319 gp_Pnt pInt = xyz[i] * (1.-r) + xyz[i+1] * r;
1320 gp_Vec p2int( point, pInt);
1321 double intDist = p2int.SquareMagnitude();
1322 if ( intDist < distClosest )
1327 distClosest = intDist;
1331 return true; // no intesections - out
1333 // analyse transition
1334 gp_Vec edge( xyz[iClosest], xyz[iClosest+1] );
1335 gp_Vec edgeNorm = -( edge ^ faceNorm ); // normal to intersected edge pointing out of face
1336 gp_Vec p2int ( point, pClosest );
1337 bool out = (edgeNorm * p2int) < -tol;
1338 if ( rClosest > 0. && rClosest < 1. ) // not node intersection
1341 // the ray passes through a face node; analyze transition through an adjacent edge
1342 gp_Pnt p1 = xyz[ (rClosest == 0.) ? ((iClosest+nbNodes-1) % nbNodes) : (iClosest+1) ];
1343 gp_Pnt p2 = xyz[ (rClosest == 0.) ? iClosest : ((iClosest+2) % nbNodes) ];
1344 gp_Vec edgeAdjacent( p1, p2 );
1345 gp_Vec edgeNorm2 = -( edgeAdjacent ^ faceNorm );
1346 bool out2 = (edgeNorm2 * p2int) < -tol;
1348 bool covexCorner = ( edgeNorm * edgeAdjacent * (rClosest==1. ? 1. : -1.)) < 0;
1349 return covexCorner ? (out || out2) : (out && out2);
1352 if ( element->GetType() == SMDSAbs_Edge ) // --------------------------------------------------
1354 // point is out of edge if it is NOT ON any straight part of edge
1355 // (we consider quadratic edge as being composed of two straight parts)
1356 for ( i = 1; i < nbNodes; ++i )
1358 gp_Vec edge( xyz[i-1], xyz[i] );
1359 gp_Vec n1p ( xyz[i-1], point );
1360 double u = ( edge * n1p ) / edge.SquareMagnitude(); // param [0,1] on the edge
1362 if ( n1p.SquareMagnitude() < tol * tol )
1367 if ( point.SquareDistance( xyz[i] ) < tol * tol )
1371 gp_XYZ proj = ( 1. - u ) * xyz[i-1] + u * xyz[i]; // projection of the point on the edge
1372 double dist2 = point.SquareDistance( proj );
1373 if ( dist2 > tol * tol )
1375 return false; // point is ON this part
1380 // Node or 0D element -------------------------------------------------------------------------
1382 gp_Vec n2p ( xyz[0], point );
1383 return n2p.SquareMagnitude() > tol * tol;
1388 //=======================================================================
1391 // Position of a point relative to a segment
1395 // VERTEX 1 o----ON-----> VERTEX 2
1399 enum PositionName { POS_LEFT = 1, POS_VERTEX = 2, POS_RIGHT = 4, //POS_ON = 8,
1400 POS_ALL = POS_LEFT | POS_RIGHT | POS_VERTEX };
1404 int _index; // index of vertex or segment
1406 PointPos( PositionName n, int i=-1 ): _name(n), _index(i) {}
1407 bool operator < (const PointPos& other ) const
1409 if ( _name == other._name )
1410 return ( _index < 0 || other._index < 0 ) ? false : _index < other._index;
1411 return _name < other._name;
1415 //================================================================================
1417 * \brief Return of a point relative to a segment
1418 * \param point2D - the point to analyze position of
1419 * \param xyVec - end points of segments
1420 * \param index0 - 0-based index of the first point of segment
1421 * \param posToFindOut - flags of positions to detect
1422 * \retval PointPos - point position
1424 //================================================================================
1426 PointPos getPointPosition( const gp_XY& point2D,
1427 const gp_XY* segEnds,
1428 const int index0 = 0,
1429 const int posToFindOut = POS_ALL)
1431 const gp_XY& p1 = segEnds[ index0 ];
1432 const gp_XY& p2 = segEnds[ index0+1 ];
1433 const gp_XY grad = p2 - p1;
1435 if ( posToFindOut & POS_VERTEX )
1437 // check if the point2D is at "vertex 1" zone
1438 gp_XY pp1[2] = { p1, gp_XY( p1.X() - grad.Y(),
1439 p1.Y() + grad.X() ) };
1440 if ( getPointPosition( point2D, pp1, 0, POS_LEFT|POS_RIGHT )._name == POS_LEFT )
1441 return PointPos( POS_VERTEX, index0 );
1443 // check if the point2D is at "vertex 2" zone
1444 gp_XY pp2[2] = { p2, gp_XY( p2.X() - grad.Y(),
1445 p2.Y() + grad.X() ) };
1446 if ( getPointPosition( point2D, pp2, 0, POS_LEFT|POS_RIGHT )._name == POS_RIGHT )
1447 return PointPos( POS_VERTEX, index0 + 1);
1449 double edgeEquation =
1450 ( point2D.X() - p1.X() ) * grad.Y() - ( point2D.Y() - p1.Y() ) * grad.X();
1451 return PointPos( edgeEquation < 0 ? POS_LEFT : POS_RIGHT, index0 );
1455 //=======================================================================
1457 * \brief Return minimal distance from a point to an element
1459 * Currently we ignore non-planarity and 2nd order of face
1461 //=======================================================================
1463 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshElement* elem,
1464 const gp_Pnt& point )
1466 switch ( elem->GetType() )
1468 case SMDSAbs_Volume:
1469 return GetDistance( dynamic_cast<const SMDS_MeshVolume*>( elem ), point);
1471 return GetDistance( dynamic_cast<const SMDS_MeshFace*>( elem ), point);
1473 return GetDistance( dynamic_cast<const SMDS_MeshEdge*>( elem ), point);
1475 return point.Distance( SMESH_TNodeXYZ( elem ));
1481 //=======================================================================
1483 * \brief Return minimal distance from a point to a face
1485 * Currently we ignore non-planarity and 2nd order of face
1487 //=======================================================================
1489 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshFace* face,
1490 const gp_Pnt& point )
1492 double badDistance = -1;
1493 if ( !face ) return badDistance;
1495 // coordinates of nodes (medium nodes, if any, ignored)
1496 typedef SMDS_StdIterator< SMESH_TNodeXYZ, SMDS_ElemIteratorPtr > TXyzIterator;
1497 vector<gp_XYZ> xyz( TXyzIterator( face->nodesIterator()), TXyzIterator() );
1498 xyz.resize( face->NbCornerNodes()+1 );
1500 // transformation to get xyz[0] lies on the origin, xyz[1] lies on the Z axis,
1501 // and xyz[2] lies in the XZ plane. This is to pass to 2D space on XZ plane.
1503 gp_Vec OZ ( xyz[0], xyz[1] );
1504 gp_Vec OX ( xyz[0], xyz[2] );
1505 if ( OZ.Magnitude() < std::numeric_limits<double>::min() )
1507 if ( xyz.size() < 4 ) return badDistance;
1508 OZ = gp_Vec ( xyz[0], xyz[2] );
1509 OX = gp_Vec ( xyz[0], xyz[3] );
1513 tgtCS = gp_Ax3( xyz[0], OZ, OX );
1515 catch ( Standard_Failure ) {
1518 trsf.SetTransformation( tgtCS );
1520 // move all the nodes to 2D
1521 vector<gp_XY> xy( xyz.size() );
1522 for ( size_t i = 0;i < xyz.size()-1; ++i )
1524 gp_XYZ p3d = xyz[i];
1525 trsf.Transforms( p3d );
1526 xy[i].SetCoord( p3d.X(), p3d.Z() );
1528 xyz.back() = xyz.front();
1529 xy.back() = xy.front();
1531 // // move the point in 2D
1532 gp_XYZ tmpPnt = point.XYZ();
1533 trsf.Transforms( tmpPnt );
1534 gp_XY point2D( tmpPnt.X(), tmpPnt.Z() );
1536 // loop on segments of the face to analyze point position ralative to the face
1537 set< PointPos > pntPosSet;
1538 for ( size_t i = 1; i < xy.size(); ++i )
1540 PointPos pos = getPointPosition( point2D, &xy[0], i-1 );
1541 pntPosSet.insert( pos );
1545 PointPos pos = *pntPosSet.begin();
1546 // cout << "Face " << face->GetID() << " DIST: ";
1547 switch ( pos._name )
1550 // point is most close to a segment
1551 gp_Vec p0p1( point, xyz[ pos._index ] );
1552 gp_Vec p1p2( xyz[ pos._index ], xyz[ pos._index+1 ]); // segment vector
1554 double projDist = p0p1 * p1p2; // distance projected to the segment
1555 gp_Vec projVec = p1p2 * projDist;
1556 gp_Vec distVec = p0p1 - projVec;
1557 // cout << distVec.Magnitude() << ", SEG " << face->GetNode(pos._index)->GetID()
1558 // << " - " << face->GetNodeWrap(pos._index+1)->GetID() << endl;
1559 return distVec.Magnitude();
1562 // point is inside the face
1563 double distToFacePlane = tmpPnt.Y();
1564 // cout << distToFacePlane << ", INSIDE " << endl;
1565 return Abs( distToFacePlane );
1568 // point is most close to a node
1569 gp_Vec distVec( point, xyz[ pos._index ]);
1570 // cout << distVec.Magnitude() << " VERTEX " << face->GetNode(pos._index)->GetID() << endl;
1571 return distVec.Magnitude();
1578 //=======================================================================
1580 * \brief Return minimal distance from a point to an edge
1582 //=======================================================================
1584 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshEdge* seg, const gp_Pnt& point )
1586 double dist = Precision::Infinite();
1587 if ( !seg ) return dist;
1589 int i = 0, nbNodes = seg->NbNodes();
1591 vector< SMESH_TNodeXYZ > xyz( nbNodes );
1592 SMDS_ElemIteratorPtr nodeIt = seg->interlacedNodesElemIterator();
1593 while ( nodeIt->more() )
1594 xyz[ i++ ].Set( nodeIt->next() );
1596 for ( i = 1; i < nbNodes; ++i )
1598 gp_Vec edge( xyz[i-1], xyz[i] );
1599 gp_Vec n1p ( xyz[i-1], point );
1600 double u = ( edge * n1p ) / edge.SquareMagnitude(); // param [0,1] on the edge
1602 dist = Min( dist, n1p.SquareMagnitude() );
1604 else if ( u >= 1. ) {
1605 dist = Min( dist, point.SquareDistance( xyz[i] ));
1608 gp_XYZ proj = ( 1. - u ) * xyz[i-1] + u * xyz[i]; // projection of the point on the edge
1609 dist = Min( dist, point.SquareDistance( proj ));
1612 return Sqrt( dist );
1615 //=======================================================================
1617 * \brief Return minimal distance from a point to a volume
1619 * Currently we ignore non-planarity and 2nd order
1621 //=======================================================================
1623 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshVolume* volume, const gp_Pnt& point )
1625 SMDS_VolumeTool vTool( volume );
1626 vTool.SetExternalNormal();
1627 const int iQ = volume->IsQuadratic() ? 2 : 1;
1630 double minDist = 1e100, dist;
1631 for ( int iF = 0; iF < vTool.NbFaces(); ++iF )
1633 // skip a facet with normal not "looking at" the point
1634 if ( !vTool.GetFaceNormal( iF, n[0], n[1], n[2] ) ||
1635 !vTool.GetFaceBaryCenter( iF, bc[0], bc[1], bc[2] ))
1637 gp_XYZ bcp = point.XYZ() - gp_XYZ( bc[0], bc[1], bc[2] );
1638 if ( gp_XYZ( n[0], n[1], n[2] ) * bcp < 1e-6 )
1641 // find distance to a facet
1642 const SMDS_MeshNode** nodes = vTool.GetFaceNodes( iF );
1643 switch ( vTool.NbFaceNodes( iF ) / iQ ) {
1646 SMDS_FaceOfNodes tmpFace( nodes[0], nodes[ 1*iQ ], nodes[ 2*iQ ] );
1647 dist = GetDistance( &tmpFace, point );
1652 SMDS_FaceOfNodes tmpFace( nodes[0], nodes[ 1*iQ ], nodes[ 2*iQ ], nodes[ 3*iQ ]);
1653 dist = GetDistance( &tmpFace, point );
1657 vector<const SMDS_MeshNode *> nvec( nodes, nodes + vTool.NbFaceNodes( iF ));
1658 SMDS_PolygonalFaceOfNodes tmpFace( nvec );
1659 dist = GetDistance( &tmpFace, point );
1661 minDist = Min( minDist, dist );
1666 //================================================================================
1668 * \brief Returns barycentric coordinates of a point within a triangle.
1669 * A not returned bc2 = 1. - bc0 - bc1.
1670 * The point lies within the triangle if ( bc0 >= 0 && bc1 >= 0 && bc0+bc1 <= 1 )
1672 //================================================================================
1674 void SMESH_MeshAlgos::GetBarycentricCoords( const gp_XY& p,
1681 const double // matrix 2x2
1682 T11 = t0.X()-t2.X(), T12 = t1.X()-t2.X(),
1683 T21 = t0.Y()-t2.Y(), T22 = t1.Y()-t2.Y();
1684 const double Tdet = T11*T22 - T12*T21; // matrix determinant
1685 if ( Abs( Tdet ) < std::numeric_limits<double>::min() )
1691 const double t11 = T22, t12 = -T12, t21 = -T21, t22 = T11;
1693 const double r11 = p.X()-t2.X(), r12 = p.Y()-t2.Y();
1694 // barycentric coordinates: mutiply matrix by vector
1695 bc0 = (t11 * r11 + t12 * r12)/Tdet;
1696 bc1 = (t21 * r11 + t22 * r12)/Tdet;
1699 //=======================================================================
1700 //function : FindFaceInSet
1701 //purpose : Return a face having linked nodes n1 and n2 and which is
1702 // - not in avoidSet,
1703 // - in elemSet provided that !elemSet.empty()
1704 // i1 and i2 optionally returns indices of n1 and n2
1705 //=======================================================================
1707 const SMDS_MeshElement*
1708 SMESH_MeshAlgos::FindFaceInSet(const SMDS_MeshNode* n1,
1709 const SMDS_MeshNode* n2,
1710 const TIDSortedElemSet& elemSet,
1711 const TIDSortedElemSet& avoidSet,
1717 const SMDS_MeshElement* face = 0;
1719 SMDS_ElemIteratorPtr invElemIt = n1->GetInverseElementIterator(SMDSAbs_Face);
1720 while ( invElemIt->more() && !face ) // loop on inverse faces of n1
1722 const SMDS_MeshElement* elem = invElemIt->next();
1723 if (avoidSet.count( elem ))
1725 if ( !elemSet.empty() && !elemSet.count( elem ))
1728 i1 = elem->GetNodeIndex( n1 );
1729 // find a n2 linked to n1
1730 int nbN = elem->IsQuadratic() ? elem->NbNodes()/2 : elem->NbNodes();
1731 for ( int di = -1; di < 2 && !face; di += 2 )
1733 i2 = (i1+di+nbN) % nbN;
1734 if ( elem->GetNode( i2 ) == n2 )
1737 if ( !face && elem->IsQuadratic())
1739 // analysis for quadratic elements using all nodes
1740 SMDS_ElemIteratorPtr anIter = elem->interlacedNodesElemIterator();
1741 const SMDS_MeshNode* prevN = static_cast<const SMDS_MeshNode*>( anIter->next() );
1742 for ( i1 = -1, i2 = 0; anIter->more() && !face; i1++, i2++ )
1744 const SMDS_MeshNode* n = static_cast<const SMDS_MeshNode*>( anIter->next() );
1745 if ( n1 == prevN && n2 == n )
1749 else if ( n2 == prevN && n1 == n )
1751 face = elem; swap( i1, i2 );
1757 if ( n1ind ) *n1ind = i1;
1758 if ( n2ind ) *n2ind = i2;
1762 //================================================================================
1764 * \brief Calculate normal of a mesh face
1766 //================================================================================
1768 bool SMESH_MeshAlgos::FaceNormal(const SMDS_MeshElement* F, gp_XYZ& normal, bool normalized)
1770 if ( !F || F->GetType() != SMDSAbs_Face )
1773 normal.SetCoord(0,0,0);
1774 int nbNodes = F->NbCornerNodes();
1775 for ( int i = 0; i < nbNodes-2; ++i )
1778 for ( int n = 0; n < 3; ++n )
1780 const SMDS_MeshNode* node = F->GetNode( i + n );
1781 p[n].SetCoord( node->X(), node->Y(), node->Z() );
1783 normal += ( p[2] - p[1] ) ^ ( p[0] - p[1] );
1785 double size2 = normal.SquareModulus();
1786 bool ok = ( size2 > numeric_limits<double>::min() * numeric_limits<double>::min());
1787 if ( normalized && ok )
1788 normal /= sqrt( size2 );
1793 //=======================================================================
1794 //function : GetCommonNodes
1795 //purpose : Return nodes common to two elements
1796 //=======================================================================
1798 vector< const SMDS_MeshNode*> SMESH_MeshAlgos::GetCommonNodes(const SMDS_MeshElement* e1,
1799 const SMDS_MeshElement* e2)
1801 vector< const SMDS_MeshNode*> common;
1802 for ( int i = 0 ; i < e1->NbNodes(); ++i )
1803 if ( e2->GetNodeIndex( e1->GetNode( i )) >= 0 )
1804 common.push_back( e1->GetNode( i ));
1808 //=======================================================================
1810 * \brief Return SMESH_NodeSearcher
1812 //=======================================================================
1814 SMESH_NodeSearcher* SMESH_MeshAlgos::GetNodeSearcher(SMDS_Mesh& mesh)
1816 return new SMESH_NodeSearcherImpl( &mesh );
1819 //=======================================================================
1821 * \brief Return SMESH_NodeSearcher
1823 //=======================================================================
1825 SMESH_NodeSearcher* SMESH_MeshAlgos::GetNodeSearcher(SMDS_ElemIteratorPtr elemIt)
1827 return new SMESH_NodeSearcherImpl( 0, elemIt );
1830 //=======================================================================
1832 * \brief Return SMESH_ElementSearcher
1834 //=======================================================================
1836 SMESH_ElementSearcher* SMESH_MeshAlgos::GetElementSearcher(SMDS_Mesh& mesh,
1839 return new SMESH_ElementSearcherImpl( mesh, tolerance );
1842 //=======================================================================
1844 * \brief Return SMESH_ElementSearcher acting on a sub-set of elements
1846 //=======================================================================
1848 SMESH_ElementSearcher* SMESH_MeshAlgos::GetElementSearcher(SMDS_Mesh& mesh,
1849 SMDS_ElemIteratorPtr elemIt,
1852 return new SMESH_ElementSearcherImpl( mesh, tolerance, elemIt );