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netgen/libsrc/occ/Partition_Inter2d.cxx
Joachim Schoeberl 3d10410665 opencascade support
2009-01-13 21:14:02 +00:00

679 lines
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#ifdef OCCGEOMETRY
// GEOM PARTITION : partition algorithm
//
// Copyright (C) 2003 OPEN CASCADE, EADS/CCR, LIP6, CEA/DEN,
// CEDRAT, EDF R& D, LEG, PRINCIPIA R& D, BUREAU VERITAS
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
// See http://www.opencascade.org/SALOME/ or email : webmaster.salome@opencascade.org
//
//
//
// File : Partition_Inter2d.cxx
// Author : Benedicte MARTIN
// Module : GEOM
// $Header: /cvs/netgen/netgen/libsrc/occ/Partition_Inter2d.cxx,v 1.5 2008/03/31 14:20:28 wabro Exp $
//using namespace std;
#include "Partition_Inter2d.ixx"
#include "utilities.h"
#include <BRepAdaptor_Curve.hxx>
#include <BRepAlgo_AsDes.hxx>
#include <BRepLib_MakeVertex.hxx>
#include <BRep_Builder.hxx>
#include <BRep_Tool.hxx>
#include <Geom_Surface.hxx>
#include <Precision.hxx>
#include <TopExp.hxx>
#include <TopExp_Explorer.hxx>
#include <TopOpeBRepDS_Transition.hxx>
#include <TopOpeBRep_EdgesIntersector.hxx>
#include <TopOpeBRep_Point2d.hxx>
#include <TopTools_ListIteratorOfListOfShape.hxx>
#include <TopTools_ListOfShape.hxx>
#include <TopTools_MapIteratorOfMapOfShape.hxx>
#include <TopTools_MapOfShape.hxx>
#include <TopoDS.hxx>
#include <TopoDS_Edge.hxx>
#include <TopoDS_Vertex.hxx>
#include <gp_Pnt.hxx>
#ifdef DEB
static Standard_Boolean TestEdges = 0;
static Standard_Integer NbF2d = 0;
static Standard_Integer NbE2d = 0;
#endif
//=======================================================================
//function : getOtherShape
//purpose :
//=======================================================================
static TopoDS_Shape getOtherShape(const TopoDS_Shape& theS,
const TopTools_ListOfShape& theSList)
{
TopTools_ListIteratorOfListOfShape anIt( theSList );
for ( ; anIt.More(); anIt.Next() )
if (!theS.IsSame( anIt.Value() ))
return anIt.Value();
return TopoDS_Shape();
}
//=======================================================================
//function : findVOnE
//purpose : on theE, find a vertex close to theV, such that an edge
// passing through it is an itersection of theF1 and theF2.
// theE intersects theE2 at theV
//=======================================================================
static Standard_Boolean findVOnE(const TopoDS_Vertex & theV,
const TopoDS_Edge& theE,
const TopoDS_Edge& theE2,
const TopoDS_Shape& theF1,
const TopoDS_Shape& theF2,
const Handle(BRepAlgo_AsDes)& theAsDes,
TopoDS_Vertex & theFoundV)
{
Standard_Real MinDist2 = ::RealLast();
gp_Pnt P;
// check all vertices on theE
const TopTools_ListOfShape& aVList = theAsDes->Descendant( theE );
TopTools_ListIteratorOfListOfShape anIt( aVList );
if (anIt.More())
P = BRep_Tool::Pnt( theV );
for ( ; anIt.More(); anIt.Next() )
{
// check by distance
TopoDS_Vertex & V = TopoDS::Vertex( anIt.Value() );
Standard_Real dist2 = P.SquareDistance( BRep_Tool::Pnt( V ));
if (dist2 < MinDist2)
MinDist2 = dist2;
else
continue;
// V is a candidate if among edges passing through V there is one
// which is an intersection of theF1 and theF2
TopTools_ListIteratorOfListOfShape anEIt( theAsDes->Ascendant( V ));
Standard_Boolean isOk = Standard_False;
for ( ; !isOk && anEIt.More(); anEIt.Next() )
{
const TopoDS_Shape & E2 = anEIt.Value();
if ( theE2.IsSame( E2 ))
continue;
const TopTools_ListOfShape & aFList = theAsDes->Ascendant( E2 );
if (aFList.IsEmpty())
continue;
if ( theF1.IsSame( aFList.First() ))
isOk = theF2.IsSame( aFList.Last() );
else
isOk = theF2.IsSame( aFList.First() ) && theF1.IsSame( aFList.Last() );
}
if (isOk)
theFoundV = V;
}
if (theFoundV.IsNull())
return Standard_False;
// check that MinDist2 is not too large
Standard_Real f, l;
TopLoc_Location L;
Handle(Geom_Curve) aCurve = BRep_Tool::Curve( theE, L, f, l );
gp_Pnt P1 = aCurve->Value( f );
gp_Pnt P2 = aCurve->Value( 0.3 * f + 0.7 * l );
//gp_Pnt P2 = aCurve->Value( 0.5 * ( f + l ));
if (MinDist2 > P1.SquareDistance( P2 ))
return Standard_False;
#ifdef DEB
MESSAGE("findVOnE: found MinDist = " << sqrt (MinDist2));
#endif
return Standard_True;
}
//=======================================================================
//function : AddVonE
//purpose : Put V in AsDes as intersection of E1 and E2.
// Check that vertex equal to V already exists on one
// of edges, in such a case, V is not added but
// existing vertex is updated to be on E1 and E2 and
// is returned insead of V.
//=======================================================================
TopoDS_Vertex Partition_Inter2d::AddVonE(const TopoDS_Vertex& theV,
const TopoDS_Edge& E1,
const TopoDS_Edge& E2,
const Handle(BRepAlgo_AsDes)& AsDes,
const TopoDS_Face& theF)
{
//-------------------------------------------------------------
// test if the points of intersection already exist. If not,
// add as descendants of the edges.
// nb: theses points are only vertices of intersection.
//-------------------------------------------------------------
const TopTools_ListOfShape& VOnE1 = AsDes->Descendant(E1);
const TopTools_ListOfShape& VOnE2 = AsDes->Descendant(E2);
gp_Pnt P1,P2;
TopoDS_Vertex V1,V2;
TopTools_ListIteratorOfListOfShape it;
BRep_Builder B;
TopAbs_Orientation O1,O2;
Standard_Real U1,U2;
Standard_Real Tol,Tol1,Tol2;
Standard_Boolean OnE1,OnE2;
TopoDS_Vertex V = theV;
U1 = BRep_Tool::Parameter(V,E1);
U2 = BRep_Tool::Parameter(V,E2);
O1 = V.Orientation();
O2 = O1;
P1 = BRep_Tool::Pnt(V);
Tol = BRep_Tool::Tolerance( V );
OnE1 = OnE2 = Standard_False;
//-----------------------------------------------------------------
// Search if the point of intersection is a vertex of E1.
//-----------------------------------------------------------------
for (it.Initialize(VOnE1); it.More(); it.Next()) {
const TopoDS_Vertex& CV = TopoDS::Vertex( it.Value() );
if (V.IsSame( CV )) {
V1 = V;
OnE1 = Standard_True;
break;
}
P2 = BRep_Tool::Pnt( CV );
Tol1 = 1.1*(Tol + BRep_Tool::Tolerance( CV ));
if (P1.SquareDistance(P2) <= Tol1*Tol1) {
V = CV;
V1 = V;
OnE1 = Standard_True;
break;
}
}
if (OnE1) {
//-----------------------------------------------------------------
// Search if the vertex found is still on E2.
//-----------------------------------------------------------------
for (it.Initialize(VOnE2); it.More(); it.Next()) {
if (V.IsSame( it.Value() )) {
OnE2 = Standard_True;
V2 = V;
break;
}
}
}
if (!OnE2) {
for (it.Initialize(VOnE2); it.More(); it.Next()) {
//-----------------------------------------------------------------
// Search if the point of intersection is a vertex of E2.
//-----------------------------------------------------------------
const TopoDS_Vertex& CV = TopoDS::Vertex( it.Value() );
P2 = BRep_Tool::Pnt( CV );
Tol2 = 1.1*(Tol + BRep_Tool::Tolerance( CV ));
if (P1.SquareDistance(P2) <= Tol2*Tol2) {
V = CV;
V2 = V;
OnE2 = Standard_True;
break;
}
}
}
if (!OnE1 && !OnE2 && !theF.IsNull())
{
// if 3 faces intersects each others, 3 new edges on them must pass
// through one vertex but real intersection points of each
// pair of edges are sometimes more far than a tolerance.
// Try to analitically find vertices that E1 and E2 must pass trough
TopoDS_Shape F1 = getOtherShape( theF, AsDes->Ascendant( E1 ));
TopoDS_Shape F2 = getOtherShape( theF, AsDes->Ascendant( E2 ));
if (!F1.IsNull() && !F2.IsNull() && !F1.IsSame( F2 ))
{
OnE1 = findVOnE ( theV, E1, E2, F1, F2, AsDes, V1 );
OnE2 = findVOnE ( theV, E2, E1, F1, F2, AsDes, V2 );
if (OnE2) V = V2;
if (OnE1) V = V1;
}
}
if (OnE1 && OnE2) {
if (!V1.IsSame(V2)) {
// replace V1 with V2 on all edges V1 is on
Standard_Real UV1;
TopoDS_Edge EWE1;
TopoDS_Vertex VI;
const TopTools_ListOfShape& EdgeWithV1 = AsDes->Ascendant(V1);
for (it.Initialize(EdgeWithV1); it.More(); it.Next()) {
EWE1 = TopoDS::Edge(it.Value());
VI = V1;
VI.Orientation(TopAbs_INTERNAL);
UV1 = BRep_Tool::Parameter(VI,EWE1);
VI = V2;
VI.Orientation(TopAbs_INTERNAL);
B.UpdateVertex( VI, UV1, EWE1, GetTolerance( VI, UV1, EWE1, AsDes));
}
AsDes->Replace(V1,V2);
V = V2;
}
}
// add existing vertices instead of new ones
if (!OnE1) {
if (OnE2) {
V.Orientation(TopAbs_INTERNAL);
B.UpdateVertex (V, U1, E1, GetTolerance( V, U1, E1, AsDes));
}
V.Orientation(O1);
AsDes->Add(E1,V);
}
if (!OnE2) {
if (OnE1) {
V.Orientation(TopAbs_INTERNAL);
B.UpdateVertex (V, U2, E2, GetTolerance( V, U2, E2, AsDes ));
}
V.Orientation(O2);
AsDes->Add(E2,V);
}
return V;
}
//=======================================================================
//function : FindEndVertex
//purpose : Returns a vertex from <VertList> having parameter on
// <E> closest to <f> or <l>. <isFirst> is True if
// found vertex is closer to <f>. <DU> returns parameter
// difference.
//=======================================================================
TopoDS_Vertex Partition_Inter2d::FindEndVertex(const TopTools_ListOfShape& LV,
const Standard_Real f,
const Standard_Real l,
const TopoDS_Edge& E,
Standard_Boolean& isFirst,
Standard_Real& minDU)
{
TopoDS_Vertex endV;
Standard_Real U, endU, min;
minDU = 1.e10;
TopTools_ListIteratorOfListOfShape it;
it.Initialize(LV);
for (; it.More(); it.Next()) {
const TopoDS_Vertex& v = TopoDS::Vertex(it.Value());
U = BRep_Tool::Parameter(v, E);
min = Min( Abs(U-f), Abs(U-l) );
if (min < minDU) {
endV = v;
endU = U;
minDU = min;
}
}
if (Abs(endU-f) < Abs(endU-l))
isFirst = Standard_True;
else
isFirst = Standard_False;
return endV;
}
//=======================================================================
//function : treatClosed
//purpose : add second vertex to closed edge. Vertex is one of <LV1>
//=======================================================================
static void treatClosed (const TopoDS_Edge& E1,
const Standard_Real f,
const Standard_Real l,
TopTools_ListOfShape& LV1,
TopTools_ListOfShape& /*LV2*/)
{
Standard_Boolean isFirst=0;
Standard_Real minDU = 1.e10;
TopoDS_Vertex endV;
endV = Partition_Inter2d::FindEndVertex(LV1, f,l, E1, isFirst,minDU);
if (minDU > Precision::PConfusion())
return; // not end point
Standard_Real newU;
if (isFirst)
newU = f + (l - f);
else
newU = l - (l - f);
// update end parameter
BRep_Builder B;
endV.Orientation(TopAbs_INTERNAL);
B.UpdateVertex(endV,newU,E1,BRep_Tool::Tolerance(endV));
}
//=======================================================================
//function : EdgesPartition
//purpose :
//=======================================================================
static void EdgesPartition(const TopoDS_Face& F,
const TopoDS_Edge& E1,
const TopoDS_Edge& E2,
const Handle(BRepAlgo_AsDes)& AsDes,
const TopTools_MapOfShape& NewEdges,
const Standard_Boolean WithOri)
{
Standard_Real f[3],l[3];
Standard_Real MilTol2;
Standard_Real Tol = Max (BRep_Tool::Tolerance(E1),
BRep_Tool::Tolerance(E2));
MilTol2 = Tol * Tol * 10;
BRep_Tool::Range(E1, f[1], l[1]);
BRep_Tool::Range(E2, f[2], l[2]);
BRepAdaptor_Curve CE1(E1,F);
BRepAdaptor_Curve CE2(E2,F);
TopoDS_Edge EI[3]; EI[1] = E1; EI[2] = E2;
TopTools_ListOfShape LV1; // new vertices at intersections on E1
TopTools_ListOfShape LV2; // ... on E2
BRep_Builder B;
// if E1 and E2 are results of intersection of F and two connex faces then
// no need to intersect edges, they can contact by vertices only
// (encounted an exception in TopOpeBRep_EdgesIntersector in such a case)
Standard_Boolean intersect = Standard_True;
TopTools_IndexedMapOfShape ME;
TopExp::MapShapes(F, TopAbs_EDGE, ME);
if (!ME.Contains(E1) && ! ME.Contains(E2)) { // if E1 and E2 are new on F
TopoDS_Shape F1, F2;
const TopTools_ListOfShape& LF1 = AsDes->Ascendant( E1 );
F1 = F.IsSame( LF1.First() ) ? LF1.Last() : LF1.First();
const TopTools_ListOfShape& LF2 = AsDes->Ascendant( E2 );
F2 = F.IsSame( LF2.First() ) ? LF2.Last() : LF2.First();
if (!F.IsSame(F2) && !F.IsSame(F1) ) {
TopExp_Explorer exp(F2, TopAbs_EDGE);
TopExp::MapShapes(F1, TopAbs_EDGE, ME);
for (; exp.More(); exp.Next()) {
if (ME.Contains( exp.Current())) {
intersect = Standard_False;
break;
}
}
}
}
if (intersect) {
//------------------------------------------------------
// compute the points of Intersection in 2D
//-----------------------------------------------------
// i.e. fill LV1 and LV2
TopOpeBRep_EdgesIntersector EInter;
EInter.SetFaces(F,F);
Standard_Real TolDub = 1.e-7;
EInter.ForceTolerances(TolDub,TolDub);
Standard_Boolean reducesegments = Standard_False;
EInter.Perform (E1,E2,reducesegments);
Standard_Boolean rejectreducedsegmentpoints = Standard_False;
EInter.InitPoint(rejectreducedsegmentpoints);
for ( ; EInter.MorePoint(); EInter.NextPoint() )
{
const TopOpeBRep_Point2d& P2D = EInter.Point();
const gp_Pnt& P = P2D.Value();
TopoDS_Vertex V = BRepLib_MakeVertex(P);
//-------------------------
// control the point found.
//-------------------------
gp_Pnt P1 = CE1.Value(P2D.Parameter(1));
gp_Pnt P2 = CE2.Value(P2D.Parameter(2));
Standard_Real sqd1 = P1.SquareDistance(P);
Standard_Real sqd2 = P2.SquareDistance(P);
if (sqd1 > MilTol2 || sqd2 > MilTol2 )
continue;
// add a new vertex to the both edges
Standard_Real toler = Max( Tol, sqrt( Max( sqd1, sqd2 )));
Standard_Integer i;
for (i = 1; i <= 2; i++) {
Standard_Real U = P2D.Parameter(i);
V.Orientation(TopAbs_INTERNAL);
B.UpdateVertex( V,U,EI[i], toler);
TopAbs_Orientation OO = TopAbs_REVERSED;
if (WithOri) {
if (P2D.IsVertex(i))
OO = P2D.Vertex(i).Orientation();
else if (P2D.Transition(i).Before() == TopAbs_OUT) {
OO = TopAbs_FORWARD;
}
V.Orientation(OO);
if (i == 1) LV1.Append(V);
else LV2.Append(V);
}
}
}
} // if (intersect)
//----------------------------------
// Test the extremities of the edges.
//----------------------------------
// add to LV* vertices for vertex-vertex closeness
Standard_Real U1,U2;
Standard_Real TolConf2, TolConf;
TopoDS_Vertex V1[2],V2[2];
TopExp::Vertices(E1,V1[0],V1[1]);
TopExp::Vertices(E2,V2[0],V2[1]);
Standard_Integer i,j,k;
for (j = 0; j < 2; j++) {
if (V1[j].IsNull()) continue;
for ( k = 0; k < 2; k++) {
if (V2[k].IsNull()) continue;
gp_Pnt P1 = BRep_Tool::Pnt(V1[j]);
gp_Pnt P2 = BRep_Tool::Pnt(V2[k]);
TolConf = BRep_Tool::Tolerance(V1[j]) + BRep_Tool::Tolerance(V2[k]);
TolConf = Max (Tol, TolConf);
TolConf2 = TolConf * TolConf;
if (!intersect)
TolConf2 *= 100;
Standard_Real SqDist = P1.SquareDistance(P2);
if (SqDist <= TolConf2) {
TopoDS_Vertex V = BRepLib_MakeVertex(P1);
V.Orientation(TopAbs_INTERNAL);
U1 = (j == 0) ? f[1] : l[1];
U2 = (k == 0) ? f[2] : l[2];
B.UpdateVertex(V,U1,E1,TolConf);
B.UpdateVertex(V,U2,E2,TolConf);
LV1.Prepend(V.Oriented(V1[j].Orientation()));
LV2.Prepend(V.Oriented(V2[k].Orientation()));
}
}
}
Standard_Boolean AffichPurge = Standard_False;
if ( LV1.IsEmpty()) return;
//----------------------------------
// Purge of all the vertices.
//----------------------------------
// remove one of close vertices
TopTools_ListIteratorOfListOfShape it1LV1,it1LV2,it2LV1;
gp_Pnt P1,P2;
Standard_Boolean Purge = Standard_True;
while (Purge) {
i = 1;
Purge = Standard_False;
for (it1LV1.Initialize(LV1),it1LV2.Initialize(LV2);
it1LV1.More();
it1LV1.Next(),it1LV2.Next()) {
j = 1;
it2LV1.Initialize(LV1);
while (j < i) {
const TopoDS_Vertex& VE1 = TopoDS::Vertex(it1LV1.Value());
const TopoDS_Vertex& VE2 = TopoDS::Vertex(it2LV1.Value());
Standard_Real Tol1 = BRep_Tool::Tolerance( VE1 );
Standard_Real Tol2 = BRep_Tool::Tolerance( VE2 );
P1 = BRep_Tool::Pnt( VE1 );
P2 = BRep_Tool::Pnt( VE2 );
if (P1.IsEqual(P2, Tol1 + Tol2)) {
LV1.Remove(it1LV1);
LV2.Remove(it1LV2);
Purge = Standard_True;
break;
}
j++;
it2LV1.Next();
}
if (Purge) break;
i++;
}
}
// care of new closed edges, they always intersect with seam at end
if (V1[0].IsSame( V1[1] ) && NewEdges.Contains(E1) )
treatClosed (E1, f[1], l[1], LV1, LV2);
if (V2[0].IsSame( V2[1] ) && NewEdges.Contains(E2) )
treatClosed (E2, f[2], l[2], LV2, LV1);
//----------------
// Stocking vertex
//----------------
for ( it1LV1.Initialize( LV1 ); it1LV1.More(); it1LV1.Next())
Partition_Inter2d::AddVonE (TopoDS::Vertex( it1LV1.Value()),
E1, E2, AsDes, F);
}
//=======================================================================
//function : CompletPart2d
//purpose : Computes the intersections between the edges stored
// is AsDes as descendants of <F> . Intersections is computed
// between two edges if one of them is bound in NewEdges.
//=======================================================================
void Partition_Inter2d::CompletPart2d (const Handle(BRepAlgo_AsDes)& AsDes,
const TopoDS_Face& F,
const TopTools_MapOfShape& NewEdges)
{
#ifdef DEB
NbF2d++;
NbE2d = 0;
#endif
//Do not intersect the edges of a face
TopTools_IndexedMapOfShape EdgesOfFace;
TopExp::MapShapes( F, TopAbs_EDGE , EdgesOfFace);
//-------------------------------------------------------------------
// compute the intersection2D on the faces touched by the intersection3D
//-------------------------------------------------------------------
TopTools_ListIteratorOfListOfShape it1LE ;
TopTools_ListIteratorOfListOfShape it2LE ;
//-----------------------------------------------
// Intersection edge-edge.
//-----------------------------------------------
const TopTools_ListOfShape& LE = AsDes->Descendant(F);
TopoDS_Vertex V1,V2;
Standard_Integer j, i = 1;
TopoDS_Face FF = F;
FF.Orientation(TopAbs_FORWARD);
for ( it1LE.Initialize(LE) ; it1LE.More(); it1LE.Next()) {
const TopoDS_Edge& E1 = TopoDS::Edge(it1LE.Value());
j = 1;
it2LE.Initialize(LE);
while (j < i && it2LE.More()) {
const TopoDS_Edge& E2 = TopoDS::Edge(it2LE.Value());
//----------------------------------------------------------
// Intersections of the new edges obtained by intersection
// between them and with the restrictions edges
//----------------------------------------------------------
if ( (!EdgesOfFace.Contains(E1) || !EdgesOfFace.Contains(E2)) &&
(NewEdges.Contains(E1) || NewEdges.Contains(E2)) ) {
EdgesPartition(FF,E1,E2,AsDes,NewEdges,Standard_True);
}
it2LE.Next();
j++;
}
i++;
}
}
//=======================================================================
//function : GetTolerance
//purpose : Returns tolerance theV must have atfer its
// addition to theE with theU parameter. theAsDes is
// used to find pcurves of theE
//=======================================================================
Standard_Real Partition_Inter2d::GetTolerance
(const TopoDS_Vertex & theV,
const Standard_Real theU,
const TopoDS_Edge & theE,
const Handle(BRepAlgo_AsDes)& theAsDes)
{
Standard_Real aTol = BRep_Tool::Tolerance( theV );
gp_Pnt aPnt = BRep_Tool::Pnt( theV );
// check point on 3D curve
Standard_Real f,l;
Handle(Geom_Curve) C = BRep_Tool::Curve( theE, f, l );
if (!C.IsNull())
aTol = Max ( aTol, aPnt.Distance( C->Value( theU )));
// check points on pcurves
const TopTools_ListOfShape& aFList = theAsDes->Ascendant( theE );
TopTools_ListIteratorOfListOfShape aFIt( aFList );
for ( ; aFIt.More(); aFIt.Next() )
{
const TopoDS_Face& F = TopoDS::Face( aFIt.Value() );
Handle(Geom2d_Curve) pcurve = BRep_Tool::CurveOnSurface( theE, F, f, l );
if (!pcurve.IsNull())
{
gp_Pnt2d aPnt2d = pcurve->Value( theU );
TopLoc_Location L;
Handle(Geom_Surface) S = BRep_Tool::Surface( F, L );
gp_Pnt aPntOnS = S->Value( aPnt2d.X(), aPnt2d.Y() );
if (!L.IsIdentity())
aPntOnS.Transform( L.Transformation() );
aTol = Max ( aTol, aPnt.Distance( aPntOnS ));
}
}
return aTol;
}
#endif
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