1 // Copyright (C) 2007-2015 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 )
65 myMesh = ( SMDS_Mesh* ) theMesh;
67 TIDSortedNodeSet nodes;
69 SMDS_NodeIteratorPtr nIt = theMesh->nodesIterator(/*idInceasingOrder=*/true);
71 nodes.insert( nodes.end(), nIt->next() );
73 myOctreeNode = new SMESH_OctreeNode(nodes) ;
75 // get max size of a leaf box
76 SMESH_OctreeNode* tree = myOctreeNode;
77 while ( !tree->isLeaf() )
79 SMESH_OctreeNodeIteratorPtr cIt = tree->GetChildrenIterator();
83 myHalfLeafSize = tree->maxSize() / 2.;
86 //---------------------------------------------------------------------
88 * \brief Move node and update myOctreeNode accordingly
90 void MoveNode( const SMDS_MeshNode* node, const gp_Pnt& toPnt )
92 myOctreeNode->UpdateByMoveNode( node, toPnt );
93 myMesh->MoveNode( node, toPnt.X(), toPnt.Y(), toPnt.Z() );
96 //---------------------------------------------------------------------
100 const SMDS_MeshNode* FindClosestTo( const gp_Pnt& thePnt )
102 map<double, const SMDS_MeshNode*> dist2Nodes;
103 myOctreeNode->NodesAround( thePnt.Coord(), dist2Nodes, myHalfLeafSize );
104 if ( !dist2Nodes.empty() )
105 return dist2Nodes.begin()->second;
106 list<const SMDS_MeshNode*> nodes;
107 //myOctreeNode->NodesAround( &tgtNode, &nodes, myHalfLeafSize );
109 double minSqDist = DBL_MAX;
110 if ( nodes.empty() ) // get all nodes of OctreeNode's closest to thePnt
112 // sort leafs by their distance from thePnt
113 typedef map< double, SMESH_OctreeNode* > TDistTreeMap;
114 TDistTreeMap treeMap;
115 list< SMESH_OctreeNode* > treeList;
116 list< SMESH_OctreeNode* >::iterator trIt;
117 treeList.push_back( myOctreeNode );
119 gp_XYZ pointNode( thePnt.X(), thePnt.Y(), thePnt.Z() );
120 bool pointInside = myOctreeNode->isInside( pointNode, myHalfLeafSize );
121 for ( trIt = treeList.begin(); trIt != treeList.end(); ++trIt)
123 SMESH_OctreeNode* tree = *trIt;
124 if ( !tree->isLeaf() ) // put children to the queue
126 if ( pointInside && !tree->isInside( pointNode, myHalfLeafSize )) continue;
127 SMESH_OctreeNodeIteratorPtr cIt = tree->GetChildrenIterator();
128 while ( cIt->more() )
129 treeList.push_back( cIt->next() );
131 else if ( tree->NbNodes() ) // put a tree to the treeMap
133 const Bnd_B3d& box = *tree->getBox();
134 double sqDist = thePnt.SquareDistance( 0.5 * ( box.CornerMin() + box.CornerMax() ));
135 pair<TDistTreeMap::iterator,bool> it_in = treeMap.insert( make_pair( sqDist, tree ));
136 if ( !it_in.second ) // not unique distance to box center
137 treeMap.insert( it_in.first, make_pair( sqDist + 1e-13*treeMap.size(), tree ));
140 // find distance after which there is no sense to check tree's
141 double sqLimit = DBL_MAX;
142 TDistTreeMap::iterator sqDist_tree = treeMap.begin();
143 if ( treeMap.size() > 5 ) {
144 SMESH_OctreeNode* closestTree = sqDist_tree->second;
145 const Bnd_B3d& box = *closestTree->getBox();
146 double limit = sqrt( sqDist_tree->first ) + sqrt ( box.SquareExtent() );
147 sqLimit = limit * limit;
149 // get all nodes from trees
150 for ( ; sqDist_tree != treeMap.end(); ++sqDist_tree) {
151 if ( sqDist_tree->first > sqLimit )
153 SMESH_OctreeNode* tree = sqDist_tree->second;
154 tree->NodesAround( tree->GetNodeIterator()->next(), &nodes );
157 // find closest among nodes
159 const SMDS_MeshNode* closestNode = 0;
160 list<const SMDS_MeshNode*>::iterator nIt = nodes.begin();
161 for ( ; nIt != nodes.end(); ++nIt ) {
162 double sqDist = thePnt.SquareDistance( SMESH_TNodeXYZ( *nIt ) );
163 if ( minSqDist > sqDist ) {
171 //---------------------------------------------------------------------
173 * \brief Finds nodes located within a tolerance near a point
175 int FindNearPoint(const gp_Pnt& point,
176 const double tolerance,
177 std::vector< const SMDS_MeshNode* >& foundNodes)
179 myOctreeNode->NodesAround( point.Coord(), foundNodes, tolerance );
180 return foundNodes.size();
183 //---------------------------------------------------------------------
187 ~SMESH_NodeSearcherImpl() { delete myOctreeNode; }
189 //---------------------------------------------------------------------
191 * \brief Return the node tree
193 const SMESH_OctreeNode* getTree() const { return myOctreeNode; }
196 SMESH_OctreeNode* myOctreeNode;
198 double myHalfLeafSize; // max size of a leaf box
201 // ========================================================================
202 namespace // Utils used in SMESH_ElementSearcherImpl::FindElementsByPoint()
204 const int MaxNbElemsInLeaf = 10; // maximal number of elements in a leaf of tree
205 const int MaxLevel = 7; // maximal tree height -> nb terminal boxes: 8^7 = 2097152
206 const double NodeRadius = 1e-9; // to enlarge bnd box of element
208 //=======================================================================
210 * \brief Octal tree of bounding boxes of elements
212 //=======================================================================
214 class ElementBndBoxTree : public SMESH_Octree
218 ElementBndBoxTree(const SMDS_Mesh& mesh,
219 SMDSAbs_ElementType elemType,
220 SMDS_ElemIteratorPtr theElemIt = SMDS_ElemIteratorPtr(),
221 double tolerance = NodeRadius );
222 void getElementsNearPoint( const gp_Pnt& point, TIDSortedElemSet& foundElems );
223 void getElementsNearLine ( const gp_Ax1& line, TIDSortedElemSet& foundElems);
224 void getElementsInSphere ( const gp_XYZ& center,
225 const double radius, TIDSortedElemSet& foundElems);
226 size_t getSize() { return std::max( _size, _elements.size() ); }
227 virtual ~ElementBndBoxTree();
230 ElementBndBoxTree():_size(0) {}
231 SMESH_Octree* newChild() const { return new ElementBndBoxTree; }
232 void buildChildrenData();
233 Bnd_B3d* buildRootBox();
235 //!< Bounding box of element
236 struct ElementBox : public Bnd_B3d
238 const SMDS_MeshElement* _element;
239 int _refCount; // an ElementBox can be included in several tree branches
240 ElementBox(const SMDS_MeshElement* elem, double tolerance);
242 vector< ElementBox* > _elements;
246 //================================================================================
248 * \brief ElementBndBoxTree creation
250 //================================================================================
252 ElementBndBoxTree::ElementBndBoxTree(const SMDS_Mesh& mesh, SMDSAbs_ElementType elemType, SMDS_ElemIteratorPtr theElemIt, double tolerance)
253 :SMESH_Octree( new SMESH_TreeLimit( MaxLevel, /*minSize=*/0. ))
255 int nbElems = mesh.GetMeshInfo().NbElements( elemType );
256 _elements.reserve( nbElems );
258 SMDS_ElemIteratorPtr elemIt = theElemIt ? theElemIt : mesh.elementsIterator( elemType );
259 while ( elemIt->more() )
260 _elements.push_back( new ElementBox( elemIt->next(),tolerance ));
265 //================================================================================
269 //================================================================================
271 ElementBndBoxTree::~ElementBndBoxTree()
273 for ( size_t i = 0; i < _elements.size(); ++i )
274 if ( --_elements[i]->_refCount <= 0 )
278 //================================================================================
280 * \brief Return the maximal box
282 //================================================================================
284 Bnd_B3d* ElementBndBoxTree::buildRootBox()
286 Bnd_B3d* box = new Bnd_B3d;
287 for ( size_t i = 0; i < _elements.size(); ++i )
288 box->Add( *_elements[i] );
292 //================================================================================
294 * \brief Redistrubute element boxes among children
296 //================================================================================
298 void ElementBndBoxTree::buildChildrenData()
300 for ( size_t i = 0; i < _elements.size(); ++i )
302 for (int j = 0; j < 8; j++)
304 if ( !_elements[i]->IsOut( *myChildren[j]->getBox() ))
306 _elements[i]->_refCount++;
307 ((ElementBndBoxTree*)myChildren[j])->_elements.push_back( _elements[i]);
310 _elements[i]->_refCount--;
312 _size = _elements.size();
313 SMESHUtils::FreeVector( _elements ); // = _elements.clear() + free memory
315 for (int j = 0; j < 8; j++)
317 ElementBndBoxTree* child = static_cast<ElementBndBoxTree*>( myChildren[j]);
318 if ((int) child->_elements.size() <= MaxNbElemsInLeaf )
319 child->myIsLeaf = true;
321 if ( child->_elements.capacity() - child->_elements.size() > 1000 )
322 SMESHUtils::CompactVector( child->_elements );
326 //================================================================================
328 * \brief Return elements which can include the point
330 //================================================================================
332 void ElementBndBoxTree::getElementsNearPoint( const gp_Pnt& point,
333 TIDSortedElemSet& foundElems)
335 if ( getBox()->IsOut( point.XYZ() ))
340 for ( size_t i = 0; i < _elements.size(); ++i )
341 if ( !_elements[i]->IsOut( point.XYZ() ))
342 foundElems.insert( _elements[i]->_element );
346 for (int i = 0; i < 8; i++)
347 ((ElementBndBoxTree*) myChildren[i])->getElementsNearPoint( point, foundElems );
351 //================================================================================
353 * \brief Return elements which can be intersected by the line
355 //================================================================================
357 void ElementBndBoxTree::getElementsNearLine( const gp_Ax1& line,
358 TIDSortedElemSet& foundElems)
360 if ( getBox()->IsOut( line ))
365 for ( size_t i = 0; i < _elements.size(); ++i )
366 if ( !_elements[i]->IsOut( line ))
367 foundElems.insert( _elements[i]->_element );
371 for (int i = 0; i < 8; i++)
372 ((ElementBndBoxTree*) myChildren[i])->getElementsNearLine( line, foundElems );
376 //================================================================================
378 * \brief Return elements from leaves intersecting the sphere
380 //================================================================================
382 void ElementBndBoxTree::getElementsInSphere ( const gp_XYZ& center,
384 TIDSortedElemSet& foundElems)
386 if ( getBox()->IsOut( center, radius ))
391 for ( size_t i = 0; i < _elements.size(); ++i )
392 if ( !_elements[i]->IsOut( center, radius ))
393 foundElems.insert( _elements[i]->_element );
397 for (int i = 0; i < 8; i++)
398 ((ElementBndBoxTree*) myChildren[i])->getElementsInSphere( center, radius, foundElems );
402 //================================================================================
404 * \brief Construct the element box
406 //================================================================================
408 ElementBndBoxTree::ElementBox::ElementBox(const SMDS_MeshElement* elem, double tolerance)
412 SMDS_ElemIteratorPtr nIt = elem->nodesIterator();
413 while ( nIt->more() )
414 Add( SMESH_TNodeXYZ( nIt->next() ));
415 Enlarge( tolerance );
420 //=======================================================================
422 * \brief Implementation of search for the elements by point and
423 * of classification of point in 2D mesh
425 //=======================================================================
427 SMESH_ElementSearcher::~SMESH_ElementSearcher()
431 struct SMESH_ElementSearcherImpl: public SMESH_ElementSearcher
434 SMDS_ElemIteratorPtr _meshPartIt;
435 ElementBndBoxTree* _ebbTree;
436 SMESH_NodeSearcherImpl* _nodeSearcher;
437 SMDSAbs_ElementType _elementType;
439 bool _outerFacesFound;
440 set<const SMDS_MeshElement*> _outerFaces; // empty means "no internal faces at all"
442 SMESH_ElementSearcherImpl( SMDS_Mesh& mesh,
444 SMDS_ElemIteratorPtr elemIt=SMDS_ElemIteratorPtr())
445 : _mesh(&mesh),_meshPartIt(elemIt),_ebbTree(0),_nodeSearcher(0),_tolerance(tol),_outerFacesFound(false) {}
446 virtual ~SMESH_ElementSearcherImpl()
448 if ( _ebbTree ) delete _ebbTree; _ebbTree = 0;
449 if ( _nodeSearcher ) delete _nodeSearcher; _nodeSearcher = 0;
451 virtual int FindElementsByPoint(const gp_Pnt& point,
452 SMDSAbs_ElementType type,
453 vector< const SMDS_MeshElement* >& foundElements);
454 virtual TopAbs_State GetPointState(const gp_Pnt& point);
455 virtual const SMDS_MeshElement* FindClosestTo( const gp_Pnt& point,
456 SMDSAbs_ElementType type );
458 void GetElementsNearLine( const gp_Ax1& line,
459 SMDSAbs_ElementType type,
460 vector< const SMDS_MeshElement* >& foundElems);
461 void GetElementsInSphere( const gp_XYZ& center,
463 SMDSAbs_ElementType type,
464 vector< const SMDS_MeshElement* >& foundElems);
465 double getTolerance();
466 bool getIntersParamOnLine(const gp_Lin& line, const SMDS_MeshElement* face,
467 const double tolerance, double & param);
468 void findOuterBoundary(const SMDS_MeshElement* anyOuterFace);
469 bool isOuterBoundary(const SMDS_MeshElement* face) const
471 return _outerFaces.empty() || _outerFaces.count(face);
474 struct TInters //!< data of intersection of the line and the mesh face (used in GetPointState())
476 const SMDS_MeshElement* _face;
478 bool _coincides; //!< the line lays in face plane
479 TInters(const SMDS_MeshElement* face, const gp_Vec& faceNorm, bool coinc=false)
480 : _face(face), _faceNorm( faceNorm ), _coincides( coinc ) {}
482 struct TFaceLink //!< link and faces sharing it (used in findOuterBoundary())
485 TIDSortedElemSet _faces;
486 TFaceLink( const SMDS_MeshNode* n1, const SMDS_MeshNode* n2, const SMDS_MeshElement* face)
487 : _link( n1, n2 ), _faces( &face, &face + 1) {}
491 ostream& operator<< (ostream& out, const SMESH_ElementSearcherImpl::TInters& i)
493 return out << "TInters(face=" << ( i._face ? i._face->GetID() : 0)
494 << ", _coincides="<<i._coincides << ")";
497 //=======================================================================
499 * \brief define tolerance for search
501 //=======================================================================
503 double SMESH_ElementSearcherImpl::getTolerance()
505 if ( _tolerance < 0 )
507 const SMDS_MeshInfo& meshInfo = _mesh->GetMeshInfo();
510 if ( _nodeSearcher && meshInfo.NbNodes() > 1 )
512 double boxSize = _nodeSearcher->getTree()->maxSize();
513 _tolerance = 1e-8 * boxSize/* / meshInfo.NbNodes()*/;
515 else if ( _ebbTree && meshInfo.NbElements() > 0 )
517 double boxSize = _ebbTree->maxSize();
518 _tolerance = 1e-8 * boxSize/* / meshInfo.NbElements()*/;
520 if ( _tolerance == 0 )
522 // define tolerance by size of a most complex element
523 int complexType = SMDSAbs_Volume;
524 while ( complexType > SMDSAbs_All &&
525 meshInfo.NbElements( SMDSAbs_ElementType( complexType )) < 1 )
527 if ( complexType == SMDSAbs_All ) return 0; // empty mesh
529 if ( complexType == int( SMDSAbs_Node ))
531 SMDS_NodeIteratorPtr nodeIt = _mesh->nodesIterator();
533 if ( meshInfo.NbNodes() > 2 )
534 elemSize = SMESH_TNodeXYZ( nodeIt->next() ).Distance( nodeIt->next() );
538 SMDS_ElemIteratorPtr elemIt =
539 _mesh->elementsIterator( SMDSAbs_ElementType( complexType ));
540 const SMDS_MeshElement* elem = elemIt->next();
541 SMDS_ElemIteratorPtr nodeIt = elem->nodesIterator();
542 SMESH_TNodeXYZ n1( nodeIt->next() );
544 while ( nodeIt->more() )
546 double dist = n1.Distance( static_cast<const SMDS_MeshNode*>( nodeIt->next() ));
547 elemSize = max( dist, elemSize );
550 _tolerance = 1e-4 * elemSize;
556 //================================================================================
558 * \brief Find intersection of the line and an edge of face and return parameter on line
560 //================================================================================
562 bool SMESH_ElementSearcherImpl::getIntersParamOnLine(const gp_Lin& line,
563 const SMDS_MeshElement* face,
570 GeomAPI_ExtremaCurveCurve anExtCC;
571 Handle(Geom_Curve) lineCurve = new Geom_Line( line );
573 int nbNodes = face->IsQuadratic() ? face->NbNodes()/2 : face->NbNodes();
574 for ( int i = 0; i < nbNodes && nbInts < 2; ++i )
576 GC_MakeSegment edge( SMESH_TNodeXYZ( face->GetNode( i )),
577 SMESH_TNodeXYZ( face->GetNode( (i+1)%nbNodes) ));
578 anExtCC.Init( lineCurve, edge);
579 if ( anExtCC.NbExtrema() > 0 && anExtCC.LowerDistance() <= tol)
581 Quantity_Parameter pl, pe;
582 anExtCC.LowerDistanceParameters( pl, pe );
588 if ( nbInts > 0 ) param /= nbInts;
591 //================================================================================
593 * \brief Find all faces belonging to the outer boundary of mesh
595 //================================================================================
597 void SMESH_ElementSearcherImpl::findOuterBoundary(const SMDS_MeshElement* outerFace)
599 if ( _outerFacesFound ) return;
601 // Collect all outer faces by passing from one outer face to another via their links
602 // and BTW find out if there are internal faces at all.
604 // checked links and links where outer boundary meets internal one
605 set< SMESH_TLink > visitedLinks, seamLinks;
607 // links to treat with already visited faces sharing them
608 list < TFaceLink > startLinks;
610 // load startLinks with the first outerFace
611 startLinks.push_back( TFaceLink( outerFace->GetNode(0), outerFace->GetNode(1), outerFace));
612 _outerFaces.insert( outerFace );
614 TIDSortedElemSet emptySet;
615 while ( !startLinks.empty() )
617 const SMESH_TLink& link = startLinks.front()._link;
618 TIDSortedElemSet& faces = startLinks.front()._faces;
620 outerFace = *faces.begin();
621 // find other faces sharing the link
622 const SMDS_MeshElement* f;
623 while (( f = SMESH_MeshAlgos::FindFaceInSet(link.node1(), link.node2(), emptySet, faces )))
626 // select another outer face among the found
627 const SMDS_MeshElement* outerFace2 = 0;
628 if ( faces.size() == 2 )
630 outerFace2 = (outerFace == *faces.begin() ? *faces.rbegin() : *faces.begin());
632 else if ( faces.size() > 2 )
634 seamLinks.insert( link );
636 // link direction within the outerFace
637 gp_Vec n1n2( SMESH_TNodeXYZ( link.node1()),
638 SMESH_TNodeXYZ( link.node2()));
639 int i1 = outerFace->GetNodeIndex( link.node1() );
640 int i2 = outerFace->GetNodeIndex( link.node2() );
641 bool rev = ( abs(i2-i1) == 1 ? i1 > i2 : i2 > i1 );
642 if ( rev ) n1n2.Reverse();
644 gp_XYZ ofNorm, fNorm;
645 if ( SMESH_MeshAlgos::FaceNormal( outerFace, ofNorm, /*normalized=*/false ))
647 // direction from the link inside outerFace
648 gp_Vec dirInOF = gp_Vec( ofNorm ) ^ n1n2;
649 // sort all other faces by angle with the dirInOF
650 map< double, const SMDS_MeshElement* > angle2Face;
651 set< const SMDS_MeshElement*, TIDCompare >::const_iterator face = faces.begin();
652 for ( ; face != faces.end(); ++face )
654 if ( *face == outerFace ) continue;
655 if ( !SMESH_MeshAlgos::FaceNormal( *face, fNorm, /*normalized=*/false ))
657 gp_Vec dirInF = gp_Vec( fNorm ) ^ n1n2;
658 double angle = dirInOF.AngleWithRef( dirInF, n1n2 );
659 if ( angle < 0 ) angle += 2. * M_PI;
660 angle2Face.insert( make_pair( angle, *face ));
662 if ( !angle2Face.empty() )
663 outerFace2 = angle2Face.begin()->second;
666 // store the found outer face and add its links to continue seaching from
669 _outerFaces.insert( outerFace2 );
670 int nbNodes = outerFace2->NbCornerNodes();
671 for ( int i = 0; i < nbNodes; ++i )
673 SMESH_TLink link2( outerFace2->GetNode(i), outerFace2->GetNode((i+1)%nbNodes));
674 if ( visitedLinks.insert( link2 ).second )
675 startLinks.push_back( TFaceLink( link2.node1(), link2.node2(), outerFace2 ));
678 startLinks.pop_front();
680 _outerFacesFound = true;
682 if ( !seamLinks.empty() )
684 // There are internal boundaries touching the outher one,
685 // find all faces of internal boundaries in order to find
686 // faces of boundaries of holes, if any.
695 //=======================================================================
697 * \brief Find elements of given type where the given point is IN or ON.
698 * Returns nb of found elements and elements them-selves.
700 * 'ALL' type means elements of any type excluding nodes, balls and 0D elements
702 //=======================================================================
704 int SMESH_ElementSearcherImpl::
705 FindElementsByPoint(const gp_Pnt& point,
706 SMDSAbs_ElementType type,
707 vector< const SMDS_MeshElement* >& foundElements)
709 foundElements.clear();
711 double tolerance = getTolerance();
713 // =================================================================================
714 if ( type == SMDSAbs_Node || type == SMDSAbs_0DElement || type == SMDSAbs_Ball)
716 if ( !_nodeSearcher )
717 _nodeSearcher = new SMESH_NodeSearcherImpl( _mesh );
719 std::vector< const SMDS_MeshNode* > foundNodes;
720 _nodeSearcher->FindNearPoint( point, tolerance, foundNodes );
722 if ( type == SMDSAbs_Node )
724 foundElements.assign( foundNodes.begin(), foundNodes.end() );
728 for ( size_t i = 0; i < foundNodes.size(); ++i )
730 SMDS_ElemIteratorPtr elemIt = foundNodes[i]->GetInverseElementIterator( type );
731 while ( elemIt->more() )
732 foundElements.push_back( elemIt->next() );
736 // =================================================================================
737 else // elements more complex than 0D
739 if ( !_ebbTree || _elementType != type )
741 if ( _ebbTree ) delete _ebbTree;
742 _ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt, tolerance );
744 TIDSortedElemSet suspectElems;
745 _ebbTree->getElementsNearPoint( point, suspectElems );
746 TIDSortedElemSet::iterator elem = suspectElems.begin();
747 for ( ; elem != suspectElems.end(); ++elem )
748 if ( !SMESH_MeshAlgos::IsOut( *elem, point, tolerance ))
749 foundElements.push_back( *elem );
751 return foundElements.size();
754 //=======================================================================
756 * \brief Find an element of given type most close to the given point
758 * WARNING: Only face search is implemeneted so far
760 //=======================================================================
762 const SMDS_MeshElement*
763 SMESH_ElementSearcherImpl::FindClosestTo( const gp_Pnt& point,
764 SMDSAbs_ElementType type )
766 const SMDS_MeshElement* closestElem = 0;
768 if ( type == SMDSAbs_Face || type == SMDSAbs_Volume )
770 if ( !_ebbTree || _elementType != type )
772 if ( _ebbTree ) delete _ebbTree;
773 _ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt );
775 TIDSortedElemSet suspectElems;
776 _ebbTree->getElementsNearPoint( point, suspectElems );
778 if ( suspectElems.empty() && _ebbTree->maxSize() > 0 )
780 gp_Pnt boxCenter = 0.5 * ( _ebbTree->getBox()->CornerMin() +
781 _ebbTree->getBox()->CornerMax() );
783 if ( _ebbTree->getBox()->IsOut( point.XYZ() ))
784 radius = point.Distance( boxCenter ) - 0.5 * _ebbTree->maxSize();
786 radius = _ebbTree->maxSize() / pow( 2., _ebbTree->getHeight()) / 2;
787 while ( suspectElems.empty() )
789 _ebbTree->getElementsInSphere( point.XYZ(), radius, suspectElems );
793 double minDist = std::numeric_limits<double>::max();
794 multimap< double, const SMDS_MeshElement* > dist2face;
795 TIDSortedElemSet::iterator elem = suspectElems.begin();
796 for ( ; elem != suspectElems.end(); ++elem )
798 double dist = SMESH_MeshAlgos::GetDistance( *elem, point );
799 if ( dist < minDist + 1e-10)
802 dist2face.insert( dist2face.begin(), make_pair( dist, *elem ));
805 if ( !dist2face.empty() )
807 multimap< double, const SMDS_MeshElement* >::iterator d2f = dist2face.begin();
808 closestElem = d2f->second;
809 // if there are several elements at the same distance, select one
810 // with GC closest to the point
811 typedef SMDS_StdIterator< SMESH_TNodeXYZ, SMDS_ElemIteratorPtr > TXyzIterator;
812 double minDistToGC = 0;
813 for ( ++d2f; d2f != dist2face.end() && fabs( d2f->first - minDist ) < 1e-10; ++d2f )
815 if ( minDistToGC == 0 )
818 gc = accumulate( TXyzIterator(closestElem->nodesIterator()),
819 TXyzIterator(), gc ) / closestElem->NbNodes();
820 minDistToGC = point.SquareDistance( gc );
823 gc = accumulate( TXyzIterator( d2f->second->nodesIterator()),
824 TXyzIterator(), gc ) / d2f->second->NbNodes();
825 double d = point.SquareDistance( gc );
826 if ( d < minDistToGC )
829 closestElem = d2f->second;
832 // cout << "FindClosestTo( " <<point.X()<<", "<<point.Y()<<", "<<point.Z()<<" ) FACE "
833 // <<closestElem->GetID() << " DIST " << minDist << endl;
838 // NOT IMPLEMENTED SO FAR
844 //================================================================================
846 * \brief Classify the given point in the closed 2D mesh
848 //================================================================================
850 TopAbs_State SMESH_ElementSearcherImpl::GetPointState(const gp_Pnt& point)
852 double tolerance = getTolerance();
853 if ( !_ebbTree || _elementType != SMDSAbs_Face )
855 if ( _ebbTree ) delete _ebbTree;
856 _ebbTree = new ElementBndBoxTree( *_mesh, _elementType = SMDSAbs_Face, _meshPartIt );
858 // Algo: analyse transition of a line starting at the point through mesh boundary;
859 // try three lines parallel to axis of the coordinate system and perform rough
860 // analysis. If solution is not clear perform thorough analysis.
862 const int nbAxes = 3;
863 gp_Dir axisDir[ nbAxes ] = { gp::DX(), gp::DY(), gp::DZ() };
864 map< double, TInters > paramOnLine2TInters[ nbAxes ];
865 list< TInters > tangentInters[ nbAxes ]; // of faces whose plane includes the line
866 multimap< int, int > nbInt2Axis; // to find the simplest case
867 for ( int axis = 0; axis < nbAxes; ++axis )
869 gp_Ax1 lineAxis( point, axisDir[axis]);
870 gp_Lin line ( lineAxis );
872 TIDSortedElemSet suspectFaces; // faces possibly intersecting the line
873 _ebbTree->getElementsNearLine( lineAxis, suspectFaces );
875 // Intersect faces with the line
877 map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
878 TIDSortedElemSet::iterator face = suspectFaces.begin();
879 for ( ; face != suspectFaces.end(); ++face )
883 if ( !SMESH_MeshAlgos::FaceNormal( *face, fNorm, /*normalized=*/false)) continue;
884 gp_Pln facePlane( SMESH_TNodeXYZ( (*face)->GetNode(0)), fNorm );
886 // perform intersection
887 IntAna_IntConicQuad intersection( line, IntAna_Quadric( facePlane ));
888 if ( !intersection.IsDone() )
890 if ( intersection.IsInQuadric() )
892 tangentInters[ axis ].push_back( TInters( *face, fNorm, true ));
894 else if ( ! intersection.IsParallel() && intersection.NbPoints() > 0 )
896 gp_Pnt intersectionPoint = intersection.Point(1);
897 if ( !SMESH_MeshAlgos::IsOut( *face, intersectionPoint, tolerance ))
898 u2inters.insert(make_pair( intersection.ParamOnConic(1), TInters( *face, fNorm )));
901 // Analyse intersections roughly
903 int nbInter = u2inters.size();
907 double f = u2inters.begin()->first, l = u2inters.rbegin()->first;
908 if ( nbInter == 1 ) // not closed mesh
909 return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
911 if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
914 if ( (f<0) == (l<0) )
917 int nbIntBeforePoint = std::distance( u2inters.begin(), u2inters.lower_bound(0));
918 int nbIntAfterPoint = nbInter - nbIntBeforePoint;
919 if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
922 nbInt2Axis.insert( make_pair( min( nbIntBeforePoint, nbIntAfterPoint ), axis ));
924 if ( _outerFacesFound ) break; // pass to thorough analysis
926 } // three attempts - loop on CS axes
928 // Analyse intersections thoroughly.
929 // We make two loops maximum, on the first one we only exclude touching intersections,
930 // on the second, if situation is still unclear, we gather and use information on
931 // position of faces (internal or outer). If faces position is already gathered,
932 // we make the second loop right away.
934 for ( int hasPositionInfo = _outerFacesFound; hasPositionInfo < 2; ++hasPositionInfo )
936 multimap< int, int >::const_iterator nb_axis = nbInt2Axis.begin();
937 for ( ; nb_axis != nbInt2Axis.end(); ++nb_axis )
939 int axis = nb_axis->second;
940 map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
942 gp_Ax1 lineAxis( point, axisDir[axis]);
943 gp_Lin line ( lineAxis );
945 // add tangent intersections to u2inters
947 list< TInters >::const_iterator tgtInt = tangentInters[ axis ].begin();
948 for ( ; tgtInt != tangentInters[ axis ].end(); ++tgtInt )
949 if ( getIntersParamOnLine( line, tgtInt->_face, tolerance, param ))
950 u2inters.insert(make_pair( param, *tgtInt ));
951 tangentInters[ axis ].clear();
953 // Count intersections before and after the point excluding touching ones.
954 // If hasPositionInfo we count intersections of outer boundary only
956 int nbIntBeforePoint = 0, nbIntAfterPoint = 0;
957 double f = numeric_limits<double>::max(), l = -numeric_limits<double>::max();
958 map< double, TInters >::iterator u_int1 = u2inters.begin(), u_int2 = u_int1;
959 bool ok = ! u_int1->second._coincides;
960 while ( ok && u_int1 != u2inters.end() )
962 double u = u_int1->first;
963 bool touchingInt = false;
964 if ( ++u_int2 != u2inters.end() )
966 // skip intersections at the same point (if the line passes through edge or node)
968 while ( u_int2 != u2inters.end() && fabs( u_int2->first - u ) < tolerance )
974 // skip tangent intersections
976 const SMDS_MeshElement* prevFace = u_int1->second._face;
977 while ( ok && u_int2->second._coincides )
979 if ( SMESH_MeshAlgos::GetCommonNodes(prevFace , u_int2->second._face).empty() )
985 ok = ( u_int2 != u2inters.end() );
990 // skip intersections at the same point after tangent intersections
993 double u2 = u_int2->first;
995 while ( u_int2 != u2inters.end() && fabs( u_int2->first - u2 ) < tolerance )
1001 // decide if we skipped a touching intersection
1002 if ( nbSamePnt + nbTgt > 0 )
1004 double minDot = numeric_limits<double>::max(), maxDot = -numeric_limits<double>::max();
1005 map< double, TInters >::iterator u_int = u_int1;
1006 for ( ; u_int != u_int2; ++u_int )
1008 if ( u_int->second._coincides ) continue;
1009 double dot = u_int->second._faceNorm * line.Direction();
1010 if ( dot > maxDot ) maxDot = dot;
1011 if ( dot < minDot ) minDot = dot;
1013 touchingInt = ( minDot*maxDot < 0 );
1018 if ( !hasPositionInfo || isOuterBoundary( u_int1->second._face ))
1029 u_int1 = u_int2; // to next intersection
1031 } // loop on intersections with one line
1035 if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
1038 if ( nbIntBeforePoint == 0 || nbIntAfterPoint == 0)
1041 if ( nbIntBeforePoint + nbIntAfterPoint == 1 ) // not closed mesh
1042 return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
1044 if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
1047 if ( (f<0) == (l<0) )
1050 if ( hasPositionInfo )
1051 return nbIntBeforePoint % 2 ? TopAbs_IN : TopAbs_OUT;
1053 } // loop on intersections of the tree lines - thorough analysis
1055 if ( !hasPositionInfo )
1057 // gather info on faces position - is face in the outer boundary or not
1058 map< double, TInters > & u2inters = paramOnLine2TInters[ 0 ];
1059 findOuterBoundary( u2inters.begin()->second._face );
1062 } // two attempts - with and w/o faces position info in the mesh
1064 return TopAbs_UNKNOWN;
1067 //=======================================================================
1069 * \brief Return elements possibly intersecting the line
1071 //=======================================================================
1073 void SMESH_ElementSearcherImpl::GetElementsNearLine( const gp_Ax1& line,
1074 SMDSAbs_ElementType type,
1075 vector< const SMDS_MeshElement* >& foundElems)
1077 if ( !_ebbTree || _elementType != type )
1079 if ( _ebbTree ) delete _ebbTree;
1080 _ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt );
1082 TIDSortedElemSet suspectFaces; // elements possibly intersecting the line
1083 _ebbTree->getElementsNearLine( line, suspectFaces );
1084 foundElems.assign( suspectFaces.begin(), suspectFaces.end());
1087 //=======================================================================
1089 * Return elements whose bounding box intersects a sphere
1091 //=======================================================================
1093 void SMESH_ElementSearcherImpl::GetElementsInSphere( const gp_XYZ& center,
1094 const double radius,
1095 SMDSAbs_ElementType type,
1096 vector< const SMDS_MeshElement* >& foundElems)
1098 if ( !_ebbTree || _elementType != type )
1100 if ( _ebbTree ) delete _ebbTree;
1101 _ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt );
1103 TIDSortedElemSet suspectFaces; // elements possibly intersecting the line
1104 _ebbTree->getElementsInSphere( center, radius, suspectFaces );
1105 foundElems.assign( suspectFaces.begin(), suspectFaces.end() );
1108 //=======================================================================
1110 * \brief Return true if the point is IN or ON of the element
1112 //=======================================================================
1114 bool SMESH_MeshAlgos::IsOut( const SMDS_MeshElement* element, const gp_Pnt& point, double tol )
1116 if ( element->GetType() == SMDSAbs_Volume)
1118 return SMDS_VolumeTool( element ).IsOut( point.X(), point.Y(), point.Z(), tol );
1121 // get ordered nodes
1123 vector< SMESH_TNodeXYZ > xyz;
1125 SMDS_ElemIteratorPtr nodeIt = element->interlacedNodesElemIterator();
1126 while ( nodeIt->more() )
1128 SMESH_TNodeXYZ node = nodeIt->next();
1129 xyz.push_back( node );
1132 int i, nbNodes = (int) xyz.size(); // central node of biquadratic is missing
1134 if ( element->GetType() == SMDSAbs_Face ) // --------------------------------------------------
1136 // compute face normal
1137 gp_Vec faceNorm(0,0,0);
1138 xyz.push_back( xyz.front() );
1139 for ( i = 0; i < nbNodes; ++i )
1141 gp_Vec edge1( xyz[i+1], xyz[i]);
1142 gp_Vec edge2( xyz[i+1], xyz[(i+2)%nbNodes] );
1143 faceNorm += edge1 ^ edge2;
1145 double normSize = faceNorm.Magnitude();
1146 if ( normSize <= tol )
1148 // degenerated face: point is out if it is out of all face edges
1149 for ( i = 0; i < nbNodes; ++i )
1151 SMDS_LinearEdge edge( xyz[i]._node, xyz[i+1]._node );
1152 if ( !IsOut( &edge, point, tol ))
1157 faceNorm /= normSize;
1159 // check if the point lays on face plane
1160 gp_Vec n2p( xyz[0], point );
1161 if ( fabs( n2p * faceNorm ) > tol )
1162 return true; // not on face plane
1164 // check if point is out of face boundary:
1165 // define it by closest transition of a ray point->infinity through face boundary
1166 // on the face plane.
1167 // First, find normal of a plane perpendicular to face plane, to be used as a cutting tool
1168 // to find intersections of the ray with the boundary.
1170 gp_Vec plnNorm = ray ^ faceNorm;
1171 normSize = plnNorm.Magnitude();
1172 if ( normSize <= tol ) return false; // point coincides with the first node
1173 plnNorm /= normSize;
1174 // for each node of the face, compute its signed distance to the plane
1175 vector<double> dist( nbNodes + 1);
1176 for ( i = 0; i < nbNodes; ++i )
1178 gp_Vec n2p( xyz[i], point );
1179 dist[i] = n2p * plnNorm;
1181 dist.back() = dist.front();
1182 // find the closest intersection
1184 double rClosest, distClosest = 1e100;;
1186 for ( i = 0; i < nbNodes; ++i )
1189 if ( fabs( dist[i]) < tol )
1191 else if ( fabs( dist[i+1]) < tol )
1193 else if ( dist[i] * dist[i+1] < 0 )
1194 r = dist[i] / ( dist[i] - dist[i+1] );
1196 continue; // no intersection
1197 gp_Pnt pInt = xyz[i] * (1.-r) + xyz[i+1] * r;
1198 gp_Vec p2int ( point, pInt);
1199 if ( p2int * ray > -tol ) // right half-space
1201 double intDist = p2int.SquareMagnitude();
1202 if ( intDist < distClosest )
1207 distClosest = intDist;
1212 return true; // no intesections - out
1214 // analyse transition
1215 gp_Vec edge( xyz[iClosest], xyz[iClosest+1] );
1216 gp_Vec edgeNorm = -( edge ^ faceNorm ); // normal to intersected edge pointing out of face
1217 gp_Vec p2int ( point, pClosest );
1218 bool out = (edgeNorm * p2int) < -tol;
1219 if ( rClosest > 0. && rClosest < 1. ) // not node intersection
1222 // ray pass through a face node; analyze transition through an adjacent edge
1223 gp_Pnt p1 = xyz[ (rClosest == 0.) ? ((iClosest+nbNodes-1) % nbNodes) : (iClosest+1) ];
1224 gp_Pnt p2 = xyz[ (rClosest == 0.) ? iClosest : ((iClosest+2) % nbNodes) ];
1225 gp_Vec edgeAdjacent( p1, p2 );
1226 gp_Vec edgeNorm2 = -( edgeAdjacent ^ faceNorm );
1227 bool out2 = (edgeNorm2 * p2int) < -tol;
1229 bool covexCorner = ( edgeNorm * edgeAdjacent * (rClosest==1. ? 1. : -1.)) < 0;
1230 return covexCorner ? (out || out2) : (out && out2);
1232 if ( element->GetType() == SMDSAbs_Edge ) // --------------------------------------------------
1234 // point is out of edge if it is NOT ON any straight part of edge
1235 // (we consider quadratic edge as being composed of two straight parts)
1236 for ( i = 1; i < nbNodes; ++i )
1238 gp_Vec edge( xyz[i-1], xyz[i] );
1239 gp_Vec n1p ( xyz[i-1], point );
1240 double u = ( edge * n1p ) / edge.SquareMagnitude(); // param [0,1] on the edge
1242 if ( n1p.SquareMagnitude() < tol * tol )
1247 if ( point.SquareDistance( xyz[i] ) < tol * tol )
1251 gp_XYZ proj = ( 1. - u ) * xyz[i-1] + u * xyz[i]; // projection of the point on the edge
1252 double dist2 = point.SquareDistance( proj );
1253 if ( dist2 > tol * tol )
1255 return false; // point is ON this part
1259 // Node or 0D element -------------------------------------------------------------------------
1261 gp_Vec n2p ( xyz[0], point );
1262 return n2p.SquareMagnitude() <= tol * tol;
1267 //=======================================================================
1270 // Position of a point relative to a segment
1274 // VERTEX 1 o----ON-----> VERTEX 2
1278 enum PositionName { POS_LEFT = 1, POS_VERTEX = 2, POS_RIGHT = 4, //POS_ON = 8,
1279 POS_ALL = POS_LEFT | POS_RIGHT | POS_VERTEX };
1283 int _index; // index of vertex or segment
1285 PointPos( PositionName n, int i=-1 ): _name(n), _index(i) {}
1286 bool operator < (const PointPos& other ) const
1288 if ( _name == other._name )
1289 return ( _index < 0 || other._index < 0 ) ? false : _index < other._index;
1290 return _name < other._name;
1294 //================================================================================
1296 * \brief Return of a point relative to a segment
1297 * \param point2D - the point to analyze position of
1298 * \param xyVec - end points of segments
1299 * \param index0 - 0-based index of the first point of segment
1300 * \param posToFindOut - flags of positions to detect
1301 * \retval PointPos - point position
1303 //================================================================================
1305 PointPos getPointPosition( const gp_XY& point2D,
1306 const gp_XY* segEnds,
1307 const int index0 = 0,
1308 const int posToFindOut = POS_ALL)
1310 const gp_XY& p1 = segEnds[ index0 ];
1311 const gp_XY& p2 = segEnds[ index0+1 ];
1312 const gp_XY grad = p2 - p1;
1314 if ( posToFindOut & POS_VERTEX )
1316 // check if the point2D is at "vertex 1" zone
1317 gp_XY pp1[2] = { p1, gp_XY( p1.X() - grad.Y(),
1318 p1.Y() + grad.X() ) };
1319 if ( getPointPosition( point2D, pp1, 0, POS_LEFT|POS_RIGHT )._name == POS_LEFT )
1320 return PointPos( POS_VERTEX, index0 );
1322 // check if the point2D is at "vertex 2" zone
1323 gp_XY pp2[2] = { p2, gp_XY( p2.X() - grad.Y(),
1324 p2.Y() + grad.X() ) };
1325 if ( getPointPosition( point2D, pp2, 0, POS_LEFT|POS_RIGHT )._name == POS_RIGHT )
1326 return PointPos( POS_VERTEX, index0 + 1);
1328 double edgeEquation =
1329 ( point2D.X() - p1.X() ) * grad.Y() - ( point2D.Y() - p1.Y() ) * grad.X();
1330 return PointPos( edgeEquation < 0 ? POS_LEFT : POS_RIGHT, index0 );
1334 //=======================================================================
1336 * \brief Return minimal distance from a point to an element
1338 * Currently we ignore non-planarity and 2nd order of face
1340 //=======================================================================
1342 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshElement* elem,
1343 const gp_Pnt& point )
1345 switch ( elem->GetType() )
1347 case SMDSAbs_Volume:
1348 return GetDistance( dynamic_cast<const SMDS_MeshVolume*>( elem ), point);
1350 return GetDistance( dynamic_cast<const SMDS_MeshFace*>( elem ), point);
1352 return GetDistance( dynamic_cast<const SMDS_MeshEdge*>( elem ), point);
1354 return point.Distance( SMESH_TNodeXYZ( elem ));
1360 //=======================================================================
1362 * \brief Return minimal distance from a point to a face
1364 * Currently we ignore non-planarity and 2nd order of face
1366 //=======================================================================
1368 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshFace* face,
1369 const gp_Pnt& point )
1371 double badDistance = -1;
1372 if ( !face ) return badDistance;
1374 // coordinates of nodes (medium nodes, if any, ignored)
1375 typedef SMDS_StdIterator< SMESH_TNodeXYZ, SMDS_ElemIteratorPtr > TXyzIterator;
1376 vector<gp_XYZ> xyz( TXyzIterator( face->nodesIterator()), TXyzIterator() );
1377 xyz.resize( face->NbCornerNodes()+1 );
1379 // transformation to get xyz[0] lies on the origin, xyz[1] lies on the Z axis,
1380 // and xyz[2] lies in the XZ plane. This is to pass to 2D space on XZ plane.
1382 gp_Vec OZ ( xyz[0], xyz[1] );
1383 gp_Vec OX ( xyz[0], xyz[2] );
1384 if ( OZ.Magnitude() < std::numeric_limits<double>::min() )
1386 if ( xyz.size() < 4 ) return badDistance;
1387 OZ = gp_Vec ( xyz[0], xyz[2] );
1388 OX = gp_Vec ( xyz[0], xyz[3] );
1392 tgtCS = gp_Ax3( xyz[0], OZ, OX );
1394 catch ( Standard_Failure ) {
1397 trsf.SetTransformation( tgtCS );
1399 // move all the nodes to 2D
1400 vector<gp_XY> xy( xyz.size() );
1401 for ( size_t i = 0;i < xyz.size()-1; ++i )
1403 gp_XYZ p3d = xyz[i];
1404 trsf.Transforms( p3d );
1405 xy[i].SetCoord( p3d.X(), p3d.Z() );
1407 xyz.back() = xyz.front();
1408 xy.back() = xy.front();
1410 // // move the point in 2D
1411 gp_XYZ tmpPnt = point.XYZ();
1412 trsf.Transforms( tmpPnt );
1413 gp_XY point2D( tmpPnt.X(), tmpPnt.Z() );
1415 // loop on segments of the face to analyze point position ralative to the face
1416 set< PointPos > pntPosSet;
1417 for ( size_t i = 1; i < xy.size(); ++i )
1419 PointPos pos = getPointPosition( point2D, &xy[0], i-1 );
1420 pntPosSet.insert( pos );
1424 PointPos pos = *pntPosSet.begin();
1425 // cout << "Face " << face->GetID() << " DIST: ";
1426 switch ( pos._name )
1429 // point is most close to a segment
1430 gp_Vec p0p1( point, xyz[ pos._index ] );
1431 gp_Vec p1p2( xyz[ pos._index ], xyz[ pos._index+1 ]); // segment vector
1433 double projDist = p0p1 * p1p2; // distance projected to the segment
1434 gp_Vec projVec = p1p2 * projDist;
1435 gp_Vec distVec = p0p1 - projVec;
1436 // cout << distVec.Magnitude() << ", SEG " << face->GetNode(pos._index)->GetID()
1437 // << " - " << face->GetNodeWrap(pos._index+1)->GetID() << endl;
1438 return distVec.Magnitude();
1441 // point is inside the face
1442 double distToFacePlane = tmpPnt.Y();
1443 // cout << distToFacePlane << ", INSIDE " << endl;
1444 return Abs( distToFacePlane );
1447 // point is most close to a node
1448 gp_Vec distVec( point, xyz[ pos._index ]);
1449 // cout << distVec.Magnitude() << " VERTEX " << face->GetNode(pos._index)->GetID() << endl;
1450 return distVec.Magnitude();
1457 //=======================================================================
1459 * \brief Return minimal distance from a point to an edge
1461 //=======================================================================
1463 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshEdge* seg, const gp_Pnt& point )
1465 double dist = Precision::Infinite();
1466 if ( !seg ) return dist;
1468 int i = 0, nbNodes = seg->NbNodes();
1470 vector< SMESH_TNodeXYZ > xyz( nbNodes );
1471 SMDS_ElemIteratorPtr nodeIt = seg->interlacedNodesElemIterator();
1472 while ( nodeIt->more() )
1473 xyz[ i++ ].Set( nodeIt->next() );
1475 for ( i = 1; i < nbNodes; ++i )
1477 gp_Vec edge( xyz[i-1], xyz[i] );
1478 gp_Vec n1p ( xyz[i-1], point );
1479 double u = ( edge * n1p ) / edge.SquareMagnitude(); // param [0,1] on the edge
1481 dist = Min( dist, n1p.SquareMagnitude() );
1483 else if ( u >= 1. ) {
1484 dist = Min( dist, point.SquareDistance( xyz[i] ));
1487 gp_XYZ proj = ( 1. - u ) * xyz[i-1] + u * xyz[i]; // projection of the point on the edge
1488 dist = Min( dist, point.SquareDistance( proj ));
1491 return Sqrt( dist );
1494 //=======================================================================
1496 * \brief Return minimal distance from a point to a volume
1498 * Currently we ignore non-planarity and 2nd order
1500 //=======================================================================
1502 double SMESH_MeshAlgos::GetDistance( const SMDS_MeshVolume* volume, const gp_Pnt& point )
1504 SMDS_VolumeTool vTool( volume );
1505 vTool.SetExternalNormal();
1506 const int iQ = volume->IsQuadratic() ? 2 : 1;
1509 double minDist = 1e100, dist;
1510 for ( int iF = 0; iF < vTool.NbFaces(); ++iF )
1512 // skip a facet with normal not "looking at" the point
1513 if ( !vTool.GetFaceNormal( iF, n[0], n[1], n[2] ) ||
1514 !vTool.GetFaceBaryCenter( iF, bc[0], bc[1], bc[2] ))
1516 gp_XYZ bcp = point.XYZ() - gp_XYZ( bc[0], bc[1], bc[2] );
1517 if ( gp_XYZ( n[0], n[1], n[2] ) * bcp < 1e-6 )
1520 // find distance to a facet
1521 const SMDS_MeshNode** nodes = vTool.GetFaceNodes( iF );
1522 switch ( vTool.NbFaceNodes( iF ) / iQ ) {
1525 SMDS_FaceOfNodes tmpFace( nodes[0], nodes[ 1*iQ ], nodes[ 2*iQ ] );
1526 dist = GetDistance( &tmpFace, point );
1531 SMDS_FaceOfNodes tmpFace( nodes[0], nodes[ 1*iQ ], nodes[ 2*iQ ], nodes[ 3*iQ ]);
1532 dist = GetDistance( &tmpFace, point );
1536 vector<const SMDS_MeshNode *> nvec( nodes, nodes + vTool.NbFaceNodes( iF ));
1537 SMDS_PolygonalFaceOfNodes tmpFace( nvec );
1538 dist = GetDistance( &tmpFace, point );
1540 minDist = Min( minDist, dist );
1545 //================================================================================
1547 * \brief Returns barycentric coordinates of a point within a triangle.
1548 * A not returned bc2 = 1. - bc0 - bc1.
1549 * The point lies within the triangle if ( bc0 >= 0 && bc1 >= 0 && bc0+bc1 <= 1 )
1551 //================================================================================
1553 void SMESH_MeshAlgos::GetBarycentricCoords( const gp_XY& p,
1560 const double // matrix 2x2
1561 T11 = t0.X()-t2.X(), T12 = t1.X()-t2.X(),
1562 T21 = t0.Y()-t2.Y(), T22 = t1.Y()-t2.Y();
1563 const double Tdet = T11*T22 - T12*T21; // matrix determinant
1564 if ( Abs( Tdet ) < std::numeric_limits<double>::min() )
1570 const double t11 = T22, t12 = -T12, t21 = -T21, t22 = T11;
1572 const double r11 = p.X()-t2.X(), r12 = p.Y()-t2.Y();
1573 // barycentric coordinates: mutiply matrix by vector
1574 bc0 = (t11 * r11 + t12 * r12)/Tdet;
1575 bc1 = (t21 * r11 + t22 * r12)/Tdet;
1578 //=======================================================================
1579 //function : FindFaceInSet
1580 //purpose : Return a face having linked nodes n1 and n2 and which is
1581 // - not in avoidSet,
1582 // - in elemSet provided that !elemSet.empty()
1583 // i1 and i2 optionally returns indices of n1 and n2
1584 //=======================================================================
1586 const SMDS_MeshElement*
1587 SMESH_MeshAlgos::FindFaceInSet(const SMDS_MeshNode* n1,
1588 const SMDS_MeshNode* n2,
1589 const TIDSortedElemSet& elemSet,
1590 const TIDSortedElemSet& avoidSet,
1596 const SMDS_MeshElement* face = 0;
1598 SMDS_ElemIteratorPtr invElemIt = n1->GetInverseElementIterator(SMDSAbs_Face);
1599 while ( invElemIt->more() && !face ) // loop on inverse faces of n1
1601 const SMDS_MeshElement* elem = invElemIt->next();
1602 if (avoidSet.count( elem ))
1604 if ( !elemSet.empty() && !elemSet.count( elem ))
1607 i1 = elem->GetNodeIndex( n1 );
1608 // find a n2 linked to n1
1609 int nbN = elem->IsQuadratic() ? elem->NbNodes()/2 : elem->NbNodes();
1610 for ( int di = -1; di < 2 && !face; di += 2 )
1612 i2 = (i1+di+nbN) % nbN;
1613 if ( elem->GetNode( i2 ) == n2 )
1616 if ( !face && elem->IsQuadratic())
1618 // analysis for quadratic elements using all nodes
1619 SMDS_ElemIteratorPtr anIter = elem->interlacedNodesElemIterator();
1620 const SMDS_MeshNode* prevN = static_cast<const SMDS_MeshNode*>( anIter->next() );
1621 for ( i1 = -1, i2 = 0; anIter->more() && !face; i1++, i2++ )
1623 const SMDS_MeshNode* n = static_cast<const SMDS_MeshNode*>( anIter->next() );
1624 if ( n1 == prevN && n2 == n )
1628 else if ( n2 == prevN && n1 == n )
1630 face = elem; swap( i1, i2 );
1636 if ( n1ind ) *n1ind = i1;
1637 if ( n2ind ) *n2ind = i2;
1641 //================================================================================
1643 * \brief Calculate normal of a mesh face
1645 //================================================================================
1647 bool SMESH_MeshAlgos::FaceNormal(const SMDS_MeshElement* F, gp_XYZ& normal, bool normalized)
1649 if ( !F || F->GetType() != SMDSAbs_Face )
1652 normal.SetCoord(0,0,0);
1653 int nbNodes = F->NbCornerNodes();
1654 for ( int i = 0; i < nbNodes-2; ++i )
1657 for ( int n = 0; n < 3; ++n )
1659 const SMDS_MeshNode* node = F->GetNode( i + n );
1660 p[n].SetCoord( node->X(), node->Y(), node->Z() );
1662 normal += ( p[2] - p[1] ) ^ ( p[0] - p[1] );
1664 double size2 = normal.SquareModulus();
1665 bool ok = ( size2 > numeric_limits<double>::min() * numeric_limits<double>::min());
1666 if ( normalized && ok )
1667 normal /= sqrt( size2 );
1672 //=======================================================================
1673 //function : GetCommonNodes
1674 //purpose : Return nodes common to two elements
1675 //=======================================================================
1677 vector< const SMDS_MeshNode*> SMESH_MeshAlgos::GetCommonNodes(const SMDS_MeshElement* e1,
1678 const SMDS_MeshElement* e2)
1680 vector< const SMDS_MeshNode*> common;
1681 for ( int i = 0 ; i < e1->NbNodes(); ++i )
1682 if ( e2->GetNodeIndex( e1->GetNode( i )) >= 0 )
1683 common.push_back( e1->GetNode( i ));
1687 //=======================================================================
1689 * \brief Return SMESH_NodeSearcher
1691 //=======================================================================
1693 SMESH_NodeSearcher* SMESH_MeshAlgos::GetNodeSearcher(SMDS_Mesh& mesh)
1695 return new SMESH_NodeSearcherImpl( &mesh );
1698 //=======================================================================
1700 * \brief Return SMESH_ElementSearcher
1702 //=======================================================================
1704 SMESH_ElementSearcher* SMESH_MeshAlgos::GetElementSearcher(SMDS_Mesh& mesh,
1707 return new SMESH_ElementSearcherImpl( mesh, tolerance );
1710 //=======================================================================
1712 * \brief Return SMESH_ElementSearcher acting on a sub-set of elements
1714 //=======================================================================
1716 SMESH_ElementSearcher* SMESH_MeshAlgos::GetElementSearcher(SMDS_Mesh& mesh,
1717 SMDS_ElemIteratorPtr elemIt,
1720 return new SMESH_ElementSearcherImpl( mesh, tolerance, elemIt );