Implementation of search for the elements by point and of classification of point in 2D mesh. More...
Inheritance diagram for SMESH_ElementSearcherImpl:
Data Structures | |
| struct | TFaceLink |
| < link and faces sharing it (used in findOuterBoundary()) More... | |
| struct | TInters |
| < data of intersection of the line and the mesh face (used in GetPointState()) More... | |
Public Member Functions | |
| SMESH_ElementSearcherImpl (SMESHDS_Mesh &mesh, SMDS_ElemIteratorPtr elemIt=SMDS_ElemIteratorPtr()) | |
| ~SMESH_ElementSearcherImpl () | |
| virtual int | FindElementsByPoint (const gp_Pnt &point, SMDSAbs_ElementType type, vector< const SMDS_MeshElement * > &foundElements) |
| Find elements of given type where the given point is IN or ON. | |
| virtual TopAbs_State | GetPointState (const gp_Pnt &point) |
| Classify the given point in the closed 2D mesh. | |
| void | GetElementsNearLine (const gp_Ax1 &line, SMDSAbs_ElementType type, vector< const SMDS_MeshElement * > &foundElems) |
| Return elements possibly intersecting the line. | |
| double | getTolerance () |
| define tolerance for search | |
| bool | getIntersParamOnLine (const gp_Lin &line, const SMDS_MeshElement *face, const double tolerance, double ¶m) |
| Find intersection of the line and an edge of face and return parameter on line. | |
| void | findOuterBoundary (const SMDS_MeshElement *anyOuterFace) |
| Find all faces belonging to the outer boundary of mesh. | |
| bool | isOuterBoundary (const SMDS_MeshElement *face) const |
Data Fields | |
| SMESHDS_Mesh * | _mesh |
| SMDS_ElemIteratorPtr | _meshPartIt |
| ElementBndBoxTree * | _ebbTree |
| SMESH_NodeSearcherImpl * | _nodeSearcher |
| SMDSAbs_ElementType | _elementType |
| double | _tolerance |
| bool | _outerFacesFound |
| set< const SMDS_MeshElement * > | _outerFaces |
Detailed Description
Implementation of search for the elements by point and of classification of point in 2D mesh.
Definition at line 6477 of file SMESH_MeshEditor.cxx.
Constructor & Destructor Documentation
| SMESH_ElementSearcherImpl.SMESH_ElementSearcherImpl | ( | SMESHDS_Mesh & | mesh, |
| SMDS_ElemIteratorPtr | elemIt = SMDS_ElemIteratorPtr() |
||
| ) |
Definition at line 6488 of file SMESH_MeshEditor.cxx.
: _mesh(&mesh),_meshPartIt(elemIt),_ebbTree(0),_nodeSearcher(0),_tolerance(-1),_outerFacesFound(false) {}
| SMESH_ElementSearcherImpl.~SMESH_ElementSearcherImpl | ( | ) |
Definition at line 6490 of file SMESH_MeshEditor.cxx.
References _ebbTree, and _nodeSearcher.
{
if ( _ebbTree ) delete _ebbTree; _ebbTree = 0;
if ( _nodeSearcher ) delete _nodeSearcher; _nodeSearcher = 0;
}
Member Function Documentation
| int SMESH_ElementSearcherImpl::FindElementsByPoint | ( | const gp_Pnt & | point, |
| SMDSAbs_ElementType | type, | ||
| vector< const SMDS_MeshElement * > & | foundElements | ||
| ) | [virtual] |
Find elements of given type where the given point is IN or ON.
Returns nb of found elements and elements them-selves.
'ALL' type means elements of any type excluding nodes and 0D elements
Implements SMESH_ElementSearcher.
Definition at line 6741 of file SMESH_MeshEditor.cxx.
References _ebbTree, _elementType, _mesh, _meshPartIt, _nodeSearcher, SMESH_NodeSearcherImpl.FindClosestTo(), SMDS_MeshNode.GetInverseElementIterator(), getTolerance(), SMESH_MeshEditor.isOut(), SMDSAbs_0DElement, and SMDSAbs_Node.
{
foundElements.clear();
double tolerance = getTolerance();
// =================================================================================
if ( type == SMDSAbs_Node || type == SMDSAbs_0DElement )
{
if ( !_nodeSearcher )
_nodeSearcher = new SMESH_NodeSearcherImpl( _mesh );
const SMDS_MeshNode* closeNode = _nodeSearcher->FindClosestTo( point );
if ( !closeNode ) return foundElements.size();
if ( point.Distance( SMESH_TNodeXYZ( closeNode )) > tolerance )
return foundElements.size(); // to far from any node
if ( type == SMDSAbs_Node )
{
foundElements.push_back( closeNode );
}
else
{
SMDS_ElemIteratorPtr elemIt = closeNode->GetInverseElementIterator( SMDSAbs_0DElement );
while ( elemIt->more() )
foundElements.push_back( elemIt->next() );
}
}
// =================================================================================
else // elements more complex than 0D
{
if ( !_ebbTree || _elementType != type )
{
if ( _ebbTree ) delete _ebbTree;
_ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt, tolerance );
}
TIDSortedElemSet suspectElems;
_ebbTree->getElementsNearPoint( point, suspectElems );
TIDSortedElemSet::iterator elem = suspectElems.begin();
for ( ; elem != suspectElems.end(); ++elem )
if ( !SMESH_MeshEditor::isOut( *elem, point, tolerance ))
foundElements.push_back( *elem );
}
return foundElements.size();
}
| void SMESH_ElementSearcherImpl::findOuterBoundary | ( | const SMDS_MeshElement * | anyOuterFace | ) |
Find all faces belonging to the outer boundary of mesh.
Definition at line 6634 of file SMESH_MeshEditor.cxx.
References _outerFaces, _outerFacesFound, SMESH_demo_hexa2_upd.angle, PAL_MESH_043_3D.face, SMESH_Algo.FaceNormal(), ex21_lamp.faces, SMESH_MeshEditor.FindFaceInSet(), SMDS_MeshElement.GetNode(), SMDS_MeshElement.GetNodeIndex(), SMESH_test.i1, SMDS_MeshElement.IsQuadratic(), SMDS_MeshElement.NbNodes(), SMESH_TLink.node1(), SMESH_TLink.node2(), and PI.
Referenced by GetPointState().
{
if ( _outerFacesFound ) return;
// Collect all outer faces by passing from one outer face to another via their links
// and BTW find out if there are internal faces at all.
// checked links and links where outer boundary meets internal one
set< SMESH_TLink > visitedLinks, seamLinks;
// links to treat with already visited faces sharing them
list < TFaceLink > startLinks;
// load startLinks with the first outerFace
startLinks.push_back( TFaceLink( outerFace->GetNode(0), outerFace->GetNode(1), outerFace));
_outerFaces.insert( outerFace );
TIDSortedElemSet emptySet;
while ( !startLinks.empty() )
{
const SMESH_TLink& link = startLinks.front()._link;
TIDSortedElemSet& faces = startLinks.front()._faces;
outerFace = *faces.begin();
// find other faces sharing the link
const SMDS_MeshElement* f;
while (( f = SMESH_MeshEditor::FindFaceInSet(link.node1(), link.node2(), emptySet, faces )))
faces.insert( f );
// select another outer face among the found
const SMDS_MeshElement* outerFace2 = 0;
if ( faces.size() == 2 )
{
outerFace2 = (outerFace == *faces.begin() ? *faces.rbegin() : *faces.begin());
}
else if ( faces.size() > 2 )
{
seamLinks.insert( link );
// link direction within the outerFace
gp_Vec n1n2( SMESH_TNodeXYZ( link.node1()),
SMESH_TNodeXYZ( link.node2()));
int i1 = outerFace->GetNodeIndex( link.node1() );
int i2 = outerFace->GetNodeIndex( link.node2() );
bool rev = ( abs(i2-i1) == 1 ? i1 > i2 : i2 > i1 );
if ( rev ) n1n2.Reverse();
// outerFace normal
gp_XYZ ofNorm, fNorm;
if ( SMESH_Algo::FaceNormal( outerFace, ofNorm, /*normalized=*/false ))
{
// direction from the link inside outerFace
gp_Vec dirInOF = gp_Vec( ofNorm ) ^ n1n2;
// sort all other faces by angle with the dirInOF
map< double, const SMDS_MeshElement* > angle2Face;
set< const SMDS_MeshElement*, TIDCompare >::const_iterator face = faces.begin();
for ( ; face != faces.end(); ++face )
{
if ( !SMESH_Algo::FaceNormal( *face, fNorm, /*normalized=*/false ))
continue;
gp_Vec dirInF = gp_Vec( fNorm ) ^ n1n2;
double angle = dirInOF.AngleWithRef( dirInF, n1n2 );
if ( angle < 0 ) angle += 2*PI;
angle2Face.insert( make_pair( angle, *face ));
}
if ( !angle2Face.empty() )
outerFace2 = angle2Face.begin()->second;
}
}
// store the found outer face and add its links to continue seaching from
if ( outerFace2 )
{
_outerFaces.insert( outerFace );
int nbNodes = outerFace2->NbNodes()/( outerFace2->IsQuadratic() ? 2 : 1 );
for ( int i = 0; i < nbNodes; ++i )
{
SMESH_TLink link2( outerFace2->GetNode(i), outerFace2->GetNode((i+1)%nbNodes));
if ( visitedLinks.insert( link2 ).second )
startLinks.push_back( TFaceLink( link2.node1(), link2.node2(), outerFace2 ));
}
}
startLinks.pop_front();
}
_outerFacesFound = true;
if ( !seamLinks.empty() )
{
// There are internal boundaries touching the outher one,
// find all faces of internal boundaries in order to find
// faces of boundaries of holes, if any.
}
else
{
_outerFaces.clear();
}
}
| void SMESH_ElementSearcherImpl::GetElementsNearLine | ( | const gp_Ax1 & | line, |
| SMDSAbs_ElementType | type, | ||
| vector< const SMDS_MeshElement * > & | foundElems | ||
| ) | [virtual] |
Return elements possibly intersecting the line.
Implements SMESH_ElementSearcher.
Definition at line 7019 of file SMESH_MeshEditor.cxx.
References _ebbTree, _elementType, _mesh, and _meshPartIt.
{
if ( !_ebbTree || _elementType != type )
{
if ( _ebbTree ) delete _ebbTree;
_ebbTree = new ElementBndBoxTree( *_mesh, _elementType = type, _meshPartIt );
}
TIDSortedElemSet suspectFaces; // elements possibly intersecting the line
_ebbTree->getElementsNearLine( line, suspectFaces );
foundElems.assign( suspectFaces.begin(), suspectFaces.end());
}
| bool SMESH_ElementSearcherImpl::getIntersParamOnLine | ( | const gp_Lin & | line, |
| const SMDS_MeshElement * | face, | ||
| const double | tolerance, | ||
| double & | param | ||
| ) |
Find intersection of the line and an edge of face and return parameter on line.
Definition at line 6599 of file SMESH_MeshEditor.cxx.
References SMESH_test.edge, SMDS_MeshElement.GetNode(), Handle(), SMDS_MeshElement.IsQuadratic(), SMDS_MeshElement.NbNodes(), and SMESH_AdvancedEditor.tol.
Referenced by GetPointState().
{
int nbInts = 0;
param = 0;
GeomAPI_ExtremaCurveCurve anExtCC;
Handle(Geom_Curve) lineCurve = new Geom_Line( line );
int nbNodes = face->IsQuadratic() ? face->NbNodes()/2 : face->NbNodes();
for ( int i = 0; i < nbNodes && nbInts < 2; ++i )
{
GC_MakeSegment edge( SMESH_TNodeXYZ( face->GetNode( i )),
SMESH_TNodeXYZ( face->GetNode( (i+1)%nbNodes) ));
anExtCC.Init( lineCurve, edge);
if ( anExtCC.NbExtrema() > 0 && anExtCC.LowerDistance() <= tol)
{
Quantity_Parameter pl, pe;
anExtCC.LowerDistanceParameters( pl, pe );
param += pl;
if ( ++nbInts == 2 )
break;
}
}
if ( nbInts > 0 ) param /= nbInts;
return nbInts > 0;
}
| TopAbs_State SMESH_ElementSearcherImpl::GetPointState | ( | const gp_Pnt & | point | ) | [virtual] |
Classify the given point in the closed 2D mesh.
Implements SMESH_ElementSearcher.
Definition at line 6796 of file SMESH_MeshEditor.cxx.
References _ebbTree, _elementType, _mesh, _meshPartIt, _outerFacesFound, PAL_MESH_043_3D.face, SMESH_Algo.FaceNormal(), findOuterBoundary(), SMESH_Algo.GetCommonNodes(), getIntersParamOnLine(), getTolerance(), SMESH_MeshEditor.isOut(), isOuterBoundary(), and SMDSAbs_Face.
{
double tolerance = getTolerance();
if ( !_ebbTree || _elementType != SMDSAbs_Face )
{
if ( _ebbTree ) delete _ebbTree;
_ebbTree = new ElementBndBoxTree( *_mesh, _elementType = SMDSAbs_Face, _meshPartIt );
}
// Algo: analyse transition of a line starting at the point through mesh boundary;
// try three lines parallel to axis of the coordinate system and perform rough
// analysis. If solution is not clear perform thorough analysis.
const int nbAxes = 3;
gp_Dir axisDir[ nbAxes ] = { gp::DX(), gp::DY(), gp::DZ() };
map< double, TInters > paramOnLine2TInters[ nbAxes ];
list< TInters > tangentInters[ nbAxes ]; // of faces whose plane includes the line
multimap< int, int > nbInt2Axis; // to find the simplest case
for ( int axis = 0; axis < nbAxes; ++axis )
{
gp_Ax1 lineAxis( point, axisDir[axis]);
gp_Lin line ( lineAxis );
TIDSortedElemSet suspectFaces; // faces possibly intersecting the line
_ebbTree->getElementsNearLine( lineAxis, suspectFaces );
// Intersect faces with the line
map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
TIDSortedElemSet::iterator face = suspectFaces.begin();
for ( ; face != suspectFaces.end(); ++face )
{
// get face plane
gp_XYZ fNorm;
if ( !SMESH_Algo::FaceNormal( *face, fNorm, /*normalized=*/false)) continue;
gp_Pln facePlane( SMESH_TNodeXYZ( (*face)->GetNode(0)), fNorm );
// perform intersection
IntAna_IntConicQuad intersection( line, IntAna_Quadric( facePlane ));
if ( !intersection.IsDone() )
continue;
if ( intersection.IsInQuadric() )
{
tangentInters[ axis ].push_back( TInters( *face, fNorm, true ));
}
else if ( ! intersection.IsParallel() && intersection.NbPoints() > 0 )
{
gp_Pnt intersectionPoint = intersection.Point(1);
if ( !SMESH_MeshEditor::isOut( *face, intersectionPoint, tolerance ))
u2inters.insert(make_pair( intersection.ParamOnConic(1), TInters( *face, fNorm )));
}
}
// Analyse intersections roughly
int nbInter = u2inters.size();
if ( nbInter == 0 )
return TopAbs_OUT;
double f = u2inters.begin()->first, l = u2inters.rbegin()->first;
if ( nbInter == 1 ) // not closed mesh
return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
return TopAbs_ON;
if ( (f<0) == (l<0) )
return TopAbs_OUT;
int nbIntBeforePoint = std::distance( u2inters.begin(), u2inters.lower_bound(0));
int nbIntAfterPoint = nbInter - nbIntBeforePoint;
if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
return TopAbs_IN;
nbInt2Axis.insert( make_pair( min( nbIntBeforePoint, nbIntAfterPoint ), axis ));
if ( _outerFacesFound ) break; // pass to thorough analysis
} // three attempts - loop on CS axes
// Analyse intersections thoroughly.
// We make two loops maximum, on the first one we only exclude touching intersections,
// on the second, if situation is still unclear, we gather and use information on
// position of faces (internal or outer). If faces position is already gathered,
// we make the second loop right away.
for ( int hasPositionInfo = _outerFacesFound; hasPositionInfo < 2; ++hasPositionInfo )
{
multimap< int, int >::const_iterator nb_axis = nbInt2Axis.begin();
for ( ; nb_axis != nbInt2Axis.end(); ++nb_axis )
{
int axis = nb_axis->second;
map< double, TInters > & u2inters = paramOnLine2TInters[ axis ];
gp_Ax1 lineAxis( point, axisDir[axis]);
gp_Lin line ( lineAxis );
// add tangent intersections to u2inters
double param;
list< TInters >::const_iterator tgtInt = tangentInters[ axis ].begin();
for ( ; tgtInt != tangentInters[ axis ].end(); ++tgtInt )
if ( getIntersParamOnLine( line, tgtInt->_face, tolerance, param ))
u2inters.insert(make_pair( param, *tgtInt ));
tangentInters[ axis ].clear();
// Count intersections before and after the point excluding touching ones.
// If hasPositionInfo we count intersections of outer boundary only
int nbIntBeforePoint = 0, nbIntAfterPoint = 0;
double f = numeric_limits<double>::max(), l = -numeric_limits<double>::max();
map< double, TInters >::iterator u_int1 = u2inters.begin(), u_int2 = u_int1;
bool ok = ! u_int1->second._coincides;
while ( ok && u_int1 != u2inters.end() )
{
double u = u_int1->first;
bool touchingInt = false;
if ( ++u_int2 != u2inters.end() )
{
// skip intersections at the same point (if the line passes through edge or node)
int nbSamePnt = 0;
while ( u_int2 != u2inters.end() && fabs( u_int2->first - u ) < tolerance )
{
++nbSamePnt;
++u_int2;
}
// skip tangent intersections
int nbTgt = 0;
const SMDS_MeshElement* prevFace = u_int1->second._face;
while ( ok && u_int2->second._coincides )
{
if ( SMESH_Algo::GetCommonNodes(prevFace , u_int2->second._face).empty() )
ok = false;
else
{
nbTgt++;
u_int2++;
ok = ( u_int2 != u2inters.end() );
}
}
if ( !ok ) break;
// skip intersections at the same point after tangent intersections
if ( nbTgt > 0 )
{
double u2 = u_int2->first;
++u_int2;
while ( u_int2 != u2inters.end() && fabs( u_int2->first - u2 ) < tolerance )
{
++nbSamePnt;
++u_int2;
}
}
// decide if we skipped a touching intersection
if ( nbSamePnt + nbTgt > 0 )
{
double minDot = numeric_limits<double>::max(), maxDot = -numeric_limits<double>::max();
map< double, TInters >::iterator u_int = u_int1;
for ( ; u_int != u_int2; ++u_int )
{
if ( u_int->second._coincides ) continue;
double dot = u_int->second._faceNorm * line.Direction();
if ( dot > maxDot ) maxDot = dot;
if ( dot < minDot ) minDot = dot;
}
touchingInt = ( minDot*maxDot < 0 );
}
}
if ( !touchingInt )
{
if ( !hasPositionInfo || isOuterBoundary( u_int1->second._face ))
{
if ( u < 0 )
++nbIntBeforePoint;
else
++nbIntAfterPoint;
}
if ( u < f ) f = u;
if ( u > l ) l = u;
}
u_int1 = u_int2; // to next intersection
} // loop on intersections with one line
if ( ok )
{
if ( fabs( f ) < tolerance || fabs( l ) < tolerance )
return TopAbs_ON;
if ( nbIntBeforePoint == 0 || nbIntAfterPoint == 0)
return TopAbs_OUT;
if ( nbIntBeforePoint + nbIntAfterPoint == 1 ) // not closed mesh
return fabs( f ) < tolerance ? TopAbs_ON : TopAbs_UNKNOWN;
if ( nbIntBeforePoint == 1 || nbIntAfterPoint == 1 )
return TopAbs_IN;
if ( (f<0) == (l<0) )
return TopAbs_OUT;
if ( hasPositionInfo )
return nbIntBeforePoint % 2 ? TopAbs_IN : TopAbs_OUT;
}
} // loop on intersections of the tree lines - thorough analysis
if ( !hasPositionInfo )
{
// gather info on faces position - is face in the outer boundary or not
map< double, TInters > & u2inters = paramOnLine2TInters[ 0 ];
findOuterBoundary( u2inters.begin()->second._face );
}
} // two attempts - with and w/o faces position info in the mesh
return TopAbs_UNKNOWN;
}
| double SMESH_ElementSearcherImpl::getTolerance | ( | ) |
define tolerance for search
Definition at line 6540 of file SMESH_MeshEditor.cxx.
References _ebbTree, _mesh, _nodeSearcher, _tolerance, cast2Node, SMESH_TNodeXYZ.Distance(), SMDS_Mesh.elementsIterator(), SMDS_Mesh.GetMeshInfo(), SMESH_NodeSearcherImpl.getTree(), SMESH_Octree.maxSize(), SMESH_AdvancedEditor.n1, SMDS_MeshInfo.NbElements(), SMDS_MeshInfo.NbNodes(), SMDS_MeshElement.nodesIterator(), SMDS_Mesh.nodesIterator(), SMDSAbs_All, SMDSAbs_Node, and SMDSAbs_Volume.
Referenced by FindElementsByPoint(), and GetPointState().
{
if ( _tolerance < 0 )
{
const SMDS_MeshInfo& meshInfo = _mesh->GetMeshInfo();
_tolerance = 0;
if ( _nodeSearcher && meshInfo.NbNodes() > 1 )
{
double boxSize = _nodeSearcher->getTree()->maxSize();
_tolerance = 1e-8 * boxSize/* / meshInfo.NbNodes()*/;
}
else if ( _ebbTree && meshInfo.NbElements() > 0 )
{
double boxSize = _ebbTree->maxSize();
_tolerance = 1e-8 * boxSize/* / meshInfo.NbElements()*/;
}
if ( _tolerance == 0 )
{
// define tolerance by size of a most complex element
int complexType = SMDSAbs_Volume;
while ( complexType > SMDSAbs_All &&
meshInfo.NbElements( SMDSAbs_ElementType( complexType )) < 1 )
--complexType;
if ( complexType == SMDSAbs_All ) return 0; // empty mesh
double elemSize;
if ( complexType == int( SMDSAbs_Node ))
{
SMDS_NodeIteratorPtr nodeIt = _mesh->nodesIterator();
elemSize = 1;
if ( meshInfo.NbNodes() > 2 )
elemSize = SMESH_TNodeXYZ( nodeIt->next() ).Distance( nodeIt->next() );
}
else
{
SMDS_ElemIteratorPtr elemIt =
_mesh->elementsIterator( SMDSAbs_ElementType( complexType ));
const SMDS_MeshElement* elem = elemIt->next();
SMDS_ElemIteratorPtr nodeIt = elem->nodesIterator();
SMESH_TNodeXYZ n1( cast2Node( nodeIt->next() ));
elemSize = 0;
while ( nodeIt->more() )
{
double dist = n1.Distance( cast2Node( nodeIt->next() ));
elemSize = max( dist, elemSize );
}
}
_tolerance = 1e-4 * elemSize;
}
}
return _tolerance;
}
| bool SMESH_ElementSearcherImpl.isOuterBoundary | ( | const SMDS_MeshElement * | face | ) | const |
Definition at line 6507 of file SMESH_MeshEditor.cxx.
References _outerFaces.
Referenced by GetPointState().
{
return _outerFaces.empty() || _outerFaces.count(face);
}
Field Documentation
| ElementBndBoxTree* SMESH_ElementSearcherImpl._ebbTree |
Definition at line 6481 of file SMESH_MeshEditor.cxx.
Referenced by FindElementsByPoint(), GetElementsNearLine(), GetPointState(), getTolerance(), and ~SMESH_ElementSearcherImpl().
Definition at line 6483 of file SMESH_MeshEditor.cxx.
Referenced by FindElementsByPoint(), GetElementsNearLine(), and GetPointState().
Definition at line 6479 of file SMESH_MeshEditor.cxx.
Referenced by FindElementsByPoint(), GetElementsNearLine(), GetPointState(), and getTolerance().
Definition at line 6480 of file SMESH_MeshEditor.cxx.
Referenced by FindElementsByPoint(), GetElementsNearLine(), and GetPointState().
Definition at line 6482 of file SMESH_MeshEditor.cxx.
Referenced by FindElementsByPoint(), getTolerance(), and ~SMESH_ElementSearcherImpl().
Definition at line 6486 of file SMESH_MeshEditor.cxx.
Referenced by findOuterBoundary(), and isOuterBoundary().
Definition at line 6485 of file SMESH_MeshEditor.cxx.
Referenced by findOuterBoundary(), and GetPointState().
Definition at line 6484 of file SMESH_MeshEditor.cxx.
Referenced by getTolerance().