diff --git a/src/BOPAlgo/BOPAlgo_PaveFiller_5.cxx b/src/BOPAlgo/BOPAlgo_PaveFiller_5.cxx
index ae20670cc5..6c4ab28a1a 100644
--- a/src/BOPAlgo/BOPAlgo_PaveFiller_5.cxx
+++ b/src/BOPAlgo/BOPAlgo_PaveFiller_5.cxx
@@ -424,8 +424,17 @@ void BOPAlgo_PaveFiller::PerformEF()
                 const TopoDS_Vertex& aV = TopoDS::Vertex(myDS->Shape(nV[j]));
                 const gp_Pnt aP = BRep_Tool::Pnt(aV);
                 Standard_Real aDistPP = aP.Distance(aPnew);
-                UpdateVertex(nV[j], aDistPP);
-                myVertsToAvoidExtension.Add(nV[j]);
+                Standard_Real aTol = BRep_Tool::Tolerance(aV);
+                Standard_Real aMaxDist = 1.e4 * aTol;
+                if (aTol < .01)
+                {
+                  aMaxDist = Min(aMaxDist, 0.1);
+                }
+                if (aDistPP < aMaxDist)
+                {
+                  UpdateVertex(nV[j], aDistPP);
+                  myVertsToAvoidExtension.Add(nV[j]);
+                }
               }
             }
             continue;
diff --git a/src/ElSLib/ElSLib.cxx b/src/ElSLib/ElSLib.cxx
index e2a815c2cd..86d7f591f5 100644
--- a/src/ElSLib/ElSLib.cxx
+++ b/src/ElSLib/ElSLib.cxx
@@ -1480,10 +1480,19 @@ void ElSLib::TorusParameters(const gp_Ax3& Pos,
   Standard_Real cosu = cos(U);
   Standard_Real sinu = sin(U);
   gp_Dir dx(cosu,sinu,0.);
-  gp_Dir dP(x - MajorRadius * cosu,
-	    y - MajorRadius * sinu,
-	    z);
-  V = dx.AngleWithRef(dP,dx^gp::DZ());
+  gp_XYZ dPV(x - MajorRadius * cosu,
+    y - MajorRadius * sinu,
+    z);
+  Standard_Real aMag = dPV.Modulus();
+  if (aMag <= gp::Resolution())
+  {
+    V = 0.;
+  }
+  else
+  {
+    gp_Dir dP(dPV);
+    V = dx.AngleWithRef(dP, dx^gp::DZ());
+  }
   if      (V < -1.e-16)  V += PIPI;
   else if (V < 0)        V = 0;
 }
diff --git a/src/Extrema/Extrema_ExtCS.cxx b/src/Extrema/Extrema_ExtCS.cxx
index 68cc4138d2..0f980966e2 100644
--- a/src/Extrema/Extrema_ExtCS.cxx
+++ b/src/Extrema/Extrema_ExtCS.cxx
@@ -39,6 +39,7 @@
 #include <Standard_OutOfRange.hxx>
 #include <StdFail_NotDone.hxx>
 #include <TColStd_Array1OfReal.hxx>
+#include <Extrema_ExtPS.hxx>
 
 Extrema_ExtCS::Extrema_ExtCS() 
 {
@@ -177,6 +178,27 @@ void Extrema_ExtCS::Perform(const Adaptor3d_Curve& C,
           if (myS->IsVPeriodic())
             NbV = 13;
 
+          if (clast - cfirst <= Precision::Confusion())
+          {
+            Standard_Real aCPar = (cfirst + clast) / 2.;
+            gp_Pnt aPm = C.Value(aCPar);
+            Extrema_ExtPS anExtPS(aPm, *myS, ufirst, ulast,
+              vfirst, vlast, mytolS, mytolS, Extrema_ExtFlag_MIN);
+            myDone = anExtPS.IsDone();
+            if (myDone) {
+              Standard_Integer NbExt = anExtPS.NbExt();
+              Standard_Real T = aCPar, U, V;
+              Extrema_POnCurv PC;
+              Extrema_POnSurf PS;
+              for (i = 1; i <= NbExt; i++) {
+                PS = anExtPS.Point(i);
+                PS.Parameter(U, V);
+                AddSolution(C, T, U, V, PC.Value(), PS.Value(), anExtPS.SquareDistance(i));
+              }
+            }
+            return;
+          }
+
           Extrema_GenExtCS Ext(C, *myS, NbT, NbU, NbV, cfirst, clast, ufirst, ulast,
             vfirst, vlast, mytolC, mytolS);
 
diff --git a/src/Extrema/Extrema_GenExtCS.cxx b/src/Extrema/Extrema_GenExtCS.cxx
index e83890b525..bae4a5dcde 100644
--- a/src/Extrema/Extrema_GenExtCS.cxx
+++ b/src/Extrema/Extrema_GenExtCS.cxx
@@ -15,19 +15,18 @@
 // commercial license or contractual agreement.
 
 
+#include <Extrema_GenExtCS.hxx>
 #include <Adaptor3d_Curve.hxx>
 #include <Adaptor3d_HCurve.hxx>
 #include <Adaptor3d_Surface.hxx>
-#include <Extrema_ExtCC.hxx>
-#include <Extrema_ExtPS.hxx>
-#include <Extrema_GenExtCS.hxx>
+#include <Adaptor3d_HSurface.hxx>
+#include <Geom_OffsetCurve.hxx>
 #include <Extrema_GlobOptFuncCS.hxx>
+#include <Extrema_GlobOptFuncConicS.hxx>
+#include <Extrema_GlobOptFuncCQuadric.hxx>
 #include <Extrema_POnCurv.hxx>
 #include <Extrema_POnSurf.hxx>
 #include <Geom_Hyperbola.hxx>
-#include <Geom_Line.hxx>
-#include <Geom_OffsetCurve.hxx>
-#include <GeomAdaptor_Curve.hxx>
 #include <math_FunctionSetRoot.hxx>
 #include <math_PSO.hxx>
 #include <math_PSOParticlesPool.hxx>
@@ -36,14 +35,32 @@
 #include <Standard_OutOfRange.hxx>
 #include <Standard_TypeMismatch.hxx>
 #include <StdFail_NotDone.hxx>
-#include <TColgp_HArray1OfPnt.hxx>
-#include <Adaptor3d_HSurface.hxx>
+#include <TColgp_Array1OfPnt.hxx>
 #include <Geom_TrimmedCurve.hxx>
+#include <ElCLib.hxx>
 
 const Standard_Real MaxParamVal = 1.0e+10;
 const Standard_Real aBorderDivisor = 1.0e+4;
 const Standard_Real HyperbolaLimit = 23.; //ln(MaxParamVal)
 
+static Standard_Boolean IsQuadric(const GeomAbs_SurfaceType theSType)
+{
+  if (theSType == GeomAbs_Plane) return Standard_True;
+  if (theSType == GeomAbs_Cylinder) return Standard_True;
+  if (theSType == GeomAbs_Cone) return Standard_True;
+  if (theSType == GeomAbs_Sphere) return Standard_True;
+  if (theSType == GeomAbs_Torus) return Standard_True;
+  return  Standard_False;
+}
+static Standard_Boolean IsConic(const GeomAbs_CurveType theCType)
+{
+  if (theCType == GeomAbs_Line) return Standard_True;
+  if (theCType == GeomAbs_Circle) return Standard_True;
+  if (theCType == GeomAbs_Ellipse) return Standard_True;
+  if (theCType == GeomAbs_Hyperbola) return Standard_True;
+  if (theCType == GeomAbs_Parabola) return Standard_True;
+  return  Standard_False;
+}
 // restrict maximal parameter on hyperbola to avoid FPE
 static Standard_Real GetCurvMaxParamVal (const Adaptor3d_Curve& theC)
 {
@@ -255,60 +272,106 @@ void Extrema_GenExtCS::Perform (const Adaptor3d_Curve& C,
     mytmin = -aCMaxVal;
   }
   //
-  math_Vector Tol(1, 3);
+  Standard_Integer aNbVar = 3;
+  GeomAbs_SurfaceType aSType = myS->GetType();
+  if (IsQuadric(aSType))
+  {
+    aNbVar = 1;
+  }
+  else
+  {
+    GeomAbs_CurveType aCType = C.GetType();
+    if (IsConic(aCType))
+    {
+      aNbVar = 2;
+    }
+  }
+
+  math_Vector Tol(1, 3), TUV(1, 3), TUVinf(1, 3), TUVsup(1, 3);
+  //
   Tol(1) = mytol1;
   Tol(2) = mytol2;
   Tol(3) = mytol2;
-  math_Vector TUV(1,3), TUVinf(1,3), TUVsup(1,3);
+  //
   TUVinf(1) = mytmin;
   TUVinf(2) = trimumin;
   TUVinf(3) = trimvmin;
-
+  //
   TUVsup(1) = mytsup;
   TUVsup(2) = trimusup;
   TUVsup(3) = trimvsup;
-
+  //
   // Number of particles used in PSO algorithm (particle swarm optimization).
   const Standard_Integer aNbParticles = 48;
+  //
+  if (aNbVar == 3)
+  {
+    GlobMinGenCS(C, aNbParticles, TUVinf, TUVsup, TUV);
+  }
+  else if (aNbVar == 2)
+  {
+    GlobMinConicS(C, aNbParticles, TUVinf, TUVsup, TUV);
+  }
+  else
+  {
+    GlobMinCQuadric(C, aNbParticles, TUVinf, TUVsup, TUV);
+  }
 
-  math_PSOParticlesPool aParticles(aNbParticles, 3);
+  // Find min approximation
+  math_FunctionSetRoot anA(myF, Tol);
+  anA.Perform(myF, TUV, TUVinf, TUVsup);
 
-  math_Vector aMinTUV(1,3);
-  aMinTUV = TUVinf + (TUVsup - TUVinf) / aBorderDivisor;
+  myDone = Standard_True;
+}
+//=======================================================================
+//function : GlobMinGenCS
+//purpose  : 
+//=======================================================================
+void Extrema_GenExtCS::GlobMinGenCS(const Adaptor3d_Curve& theC,
+                                    const Standard_Integer theNbParticles, 
+                                    const math_Vector& theTUVinf, 
+                                    const math_Vector& theTUVsup,
+                                    math_Vector& theTUV)
+{
+  math_PSOParticlesPool aParticles(theNbParticles, 3);
 
-  math_Vector aMaxTUV(1,3); 
-  aMaxTUV = TUVsup - (TUVsup - TUVinf) / aBorderDivisor;
+  math_Vector aMinTUV(1, 3);
+  aMinTUV = theTUVinf + (theTUVsup - theTUVinf) / aBorderDivisor;
+
+  math_Vector aMaxTUV(1, 3);
+  aMaxTUV = theTUVsup - (theTUVsup - theTUVinf) / aBorderDivisor;
 
   Standard_Real aStepCU = (aMaxTUV(1) - aMinTUV(1)) / mytsample;
   Standard_Real aStepSU = (aMaxTUV(2) - aMinTUV(2)) / myusample;
   Standard_Real aStepSV = (aMaxTUV(3) - aMinTUV(3)) / myvsample;
 
   // Correct number of curve samples in case of low resolution
+  Standard_Integer aNewCsample = mytsample;
   Standard_Real aScaleFactor = 5.0;
-  Standard_Real aResolutionCU = aStepCU / C.Resolution (1.0);
+  Standard_Real aResolutionCU = aStepCU / theC.Resolution(1.0);
 
-  Standard_Real aMinResolution = aScaleFactor * Min (aResolutionCU,
-    Min (aStepSU / myS->UResolution (1.0), aStepSV / myS->VResolution (1.0)));
+  Standard_Real aMinResolution = aScaleFactor * Min(aResolutionCU,
+    Min(aStepSU / myS->UResolution(1.0), aStepSV / myS->VResolution(1.0)));
 
-  if (aMinResolution > Epsilon (1.0))
+  if (aMinResolution > Epsilon(1.0))
   {
     if (aResolutionCU > aMinResolution)
     {
       const Standard_Integer aMaxNbNodes = 50;
 
-      mytsample = Min(aMaxNbNodes,
+      aNewCsample = Min(aMaxNbNodes,
         RealToInt(mytsample * aResolutionCU / aMinResolution));
 
-      aStepCU = (aMaxTUV(1) - aMinTUV(1)) / mytsample;
+      aStepCU = (aMaxTUV(1) - aMinTUV(1)) / aNewCsample;
     }
   }
 
   // Pre-compute curve sample points.
-  TColgp_HArray1OfPnt aCurvPnts (0, mytsample);
+  TColgp_Array1OfPnt aCurvPnts(0, aNewCsample);
 
   Standard_Real aCU1 = aMinTUV(1);
-  for (Standard_Integer aCUI = 0; aCUI <= mytsample; aCUI++, aCU1 += aStepCU)
-    aCurvPnts.SetValue (aCUI, C.Value (aCU1));
+  for (Standard_Integer aCUI = 0; aCUI <= aNewCsample; aCUI++, aCU1 += aStepCU)
+    aCurvPnts.SetValue(aCUI, theC.Value(aCU1));
 
   PSO_Particle* aParticle = aParticles.GetWorstParticle();
   // Select specified number of particles from pre-computed set of samples
@@ -319,9 +382,9 @@ void Extrema_GenExtCS::Perform (const Adaptor3d_Curve& C,
     for (Standard_Integer aSVI = 0; aSVI <= myvsample; aSVI++, aSV += aStepSV)
     {
       Standard_Real aCU2 = aMinTUV(1);
-      for (Standard_Integer aCUI = 0; aCUI <= mytsample; aCUI++, aCU2 += aStepCU)
+      for (Standard_Integer aCUI = 0; aCUI <= aNewCsample; aCUI++, aCU2 += aStepCU)
       {
-        Standard_Real aSqDist = mySurfPnts->Value(aSUI, aSVI).SquareDistance(aCurvPnts.Value(aCUI)); 
+        Standard_Real aSqDist = mySurfPnts->Value(aSUI, aSVI).SquareDistance(aCurvPnts.Value(aCUI));
 
         if (aSqDist < aParticle->Distance)
         {
@@ -333,7 +396,7 @@ void Extrema_GenExtCS::Perform (const Adaptor3d_Curve& C,
           aParticle->BestPosition[1] = aSU;
           aParticle->BestPosition[2] = aSV;
 
-          aParticle->Distance     = aSqDist;
+          aParticle->Distance = aSqDist;
           aParticle->BestDistance = aSqDist;
 
           aParticle = aParticles.GetWorstParticle();
@@ -342,21 +405,225 @@ void Extrema_GenExtCS::Perform (const Adaptor3d_Curve& C,
     }
   }
 
-  math_Vector aStep(1,3);
+  math_Vector aStep(1, 3);
   aStep(1) = aStepCU;
   aStep(2) = aStepSU;
   aStep(3) = aStepSV;
 
   // Find min approximation
   Standard_Real aValue;
-  Extrema_GlobOptFuncCS aFunc(&C, myS);
-  math_PSO aPSO(&aFunc, TUVinf, TUVsup, aStep);
-  aPSO.Perform(aParticles, aNbParticles, aValue, TUV);
+  Extrema_GlobOptFuncCS aFunc(&theC, myS);
+  math_PSO aPSO(&aFunc, theTUVinf, theTUVsup, aStep);
+  aPSO.Perform(aParticles, theNbParticles, aValue, theTUV);
 
-  math_FunctionSetRoot anA(myF, Tol);
-  anA.Perform(myF, TUV, TUVinf, TUVsup);
+}
+//=======================================================================
+//function : GlobMinConicS
+//purpose  : 
+//=======================================================================
+void Extrema_GenExtCS::GlobMinConicS(const Adaptor3d_Curve& theC,
+  const Standard_Integer theNbParticles,
+  const math_Vector& theTUVinf,
+  const math_Vector& theTUVsup,
+  math_Vector& theTUV)
+{
+  Standard_Integer aNbVar = 2;
+  math_Vector  anUVinf(1, aNbVar), anUVsup(1, aNbVar), anUV(1, aNbVar);
+  Standard_Integer i;
+  for (i = 1; i <= aNbVar; ++i)
+  {
+    anUVinf(i) = theTUVinf(i + 1);
+    anUVsup(i) = theTUVsup(i + 1);
+  }
+  //
+  math_PSOParticlesPool aParticles(theNbParticles, aNbVar);
+
+  math_Vector aMinUV(1, aNbVar);
+  aMinUV = anUVinf + (anUVsup - anUVinf) / aBorderDivisor;
+
+  math_Vector aMaxUV(1, aNbVar);
+  aMaxUV = anUVsup - (anUVsup - anUVinf) / aBorderDivisor;
+
+  //Increase numbers of UV samples to improve searching global minimum
+  Standard_Integer anAddsample = Max(mytsample / 2, 3);
+  Standard_Integer anUsample = myusample + anAddsample;
+  Standard_Integer aVsample = myvsample + anAddsample;
+  //
+  Standard_Real aStepSU = (aMaxUV(1) - aMinUV(1)) / anUsample;
+  Standard_Real aStepSV = (aMaxUV(2) - aMinUV(2)) / aVsample;
+  //
+  Extrema_GlobOptFuncConicS aFunc(myS, anUVinf(1), anUVsup(1), anUVinf(2), anUVsup(2));
+  aFunc.LoadConic(&theC, theTUVinf(1), theTUVsup(1));
+
+
+  PSO_Particle* aParticle = aParticles.GetWorstParticle();
+  // Select specified number of particles from pre-computed set of samples
+  Standard_Real aSU = aMinUV(1);
+  
+  for (Standard_Integer aSUI = 0; aSUI <= anUsample; aSUI++, aSU += aStepSU)
+  {
+    anUV(1) = aSU;
+    Standard_Real aSV = aMinUV(2);
+    for (Standard_Integer aSVI = 0; aSVI <= aVsample; aSVI++, aSV += aStepSV)
+    {
+      anUV(2) = aSV;
+      Standard_Real aSqDist;
+      if (!aFunc.Value(anUV, aSqDist))
+      {
+        aSqDist = Precision::Infinite();
+      }
+
+      if (aSqDist < aParticle->Distance)
+      {
+        aParticle->Position[0] = aSU;
+        aParticle->Position[1] = aSV;
+
+        aParticle->BestPosition[0] = aSU;
+        aParticle->BestPosition[1] = aSV;
+
+        aParticle->Distance = aSqDist;
+        aParticle->BestDistance = aSqDist;
+
+        aParticle = aParticles.GetWorstParticle();
+      }
+    }
+  }
+
+  math_Vector aStep(1, aNbVar);
+  aStep(1) = aStepSU;
+  aStep(2) = aStepSV;
+
+  // Find min approximation
+  Standard_Real aValue;
+  math_PSO aPSO(&aFunc, anUVinf, anUVsup, aStep);
+  aPSO.Perform(aParticles, theNbParticles, aValue, anUV);
+  //
+  Standard_Real aCT = aFunc.ConicParameter(anUV);
+  if (theC.IsPeriodic())
+  {
+    if (aCT <  theTUVinf(1) - Precision::PConfusion() || aCT >  theTUVsup(1) + Precision::PConfusion())
+    {
+      aCT = ElCLib::InPeriod(aCT, theTUVinf(1), theTUVinf(1) + 2. * M_PI);
+    }
+  }
+  theTUV(1) = aCT;
+  theTUV(2) = anUV(1);
+  theTUV(3) = anUV(2);
+
+}
+//=======================================================================
+//function : GlobMinCQuadric
+//purpose  : 
+//=======================================================================
+void Extrema_GenExtCS::GlobMinCQuadric(const Adaptor3d_Curve& theC,
+  const Standard_Integer theNbParticles,
+  const math_Vector& theTUVinf,
+  const math_Vector& theTUVsup,
+  math_Vector& theTUV)
+{
+  Standard_Integer aNbVar = 1;
+  math_Vector aTinf(1, aNbVar), aTsup(1, aNbVar), aT(1, aNbVar);
+  aTinf(1) = theTUVinf(1);
+  aTsup(1) = theTUVsup(1);
+  //
+  math_PSOParticlesPool aParticles(theNbParticles, aNbVar);
+
+  math_Vector aMinT(1, aNbVar);
+  aMinT = aTinf + (aTsup - aTinf) / aBorderDivisor;
+
+  math_Vector aMaxT(1, aNbVar);
+  aMaxT = aTsup - (aTsup - aTinf) / aBorderDivisor;
+  //
+
+  //Increase numbers of curve samples to improve searching global minimum
+  //because dimension of optimisation task is redused
+  const Standard_Integer aMaxNbNodes = 50;
+  Standard_Integer aNewCsample = mytsample;
+  Standard_Integer anAddsample = Max(myusample / 2, 3);
+  aNewCsample += anAddsample;
+  aNewCsample = Min(aNewCsample, aMaxNbNodes);
+  //
+  // Correct number of curve samples in case of low resolution
+  Standard_Real aStepCT = (aMaxT(1) - aMinT(1)) / aNewCsample;
+  Standard_Real aStepSU = (theTUVsup(2) - theTUVinf(2)) / myusample;
+  Standard_Real aStepSV = (theTUVsup(3) - theTUVinf(3)) / myvsample;
+  Standard_Real aScaleFactor = 5.0;
+  Standard_Real aResolutionCU = aStepCT / theC.Resolution(1.0);
+
+  Standard_Real aMinResolution = aScaleFactor * Min(aResolutionCU,
+    Min(aStepSU / myS->UResolution(1.0), aStepSV / myS->VResolution(1.0)));
+
+  if (aMinResolution > Epsilon(1.0))
+  {
+    if (aResolutionCU > aMinResolution)
+    {
+
+      aNewCsample = Min(aMaxNbNodes,
+        RealToInt(aNewCsample * aResolutionCU / aMinResolution));
+
+      aStepCT = (aMaxT(1) - aMinT(1)) / aNewCsample;
+    }
+  }
+
+  //
+  Extrema_GlobOptFuncCQuadric aFunc(&theC, aTinf(1), aTsup(1));
+  aFunc.LoadQuad(myS, theTUVinf(2), theTUVsup(2), theTUVinf(3), theTUVsup(3));
+
+  PSO_Particle* aParticle = aParticles.GetWorstParticle();
+  // Select specified number of particles from pre-computed set of samples
+  Standard_Real aCT = aMinT(1);
+  for (Standard_Integer aCUI = 0; aCUI <= aNewCsample; aCUI++, aCT += aStepCT)
+  {
+    aT(1) = aCT;
+    Standard_Real aSqDist; 
+    if (!aFunc.Value(aT, aSqDist))
+    {
+      aSqDist = Precision::Infinite();
+    }
+
+    if (aSqDist < aParticle->Distance)
+    {
+      aParticle->Position[0] = aCT;
+
+      aParticle->BestPosition[0] = aCT;
+
+      aParticle->Distance = aSqDist;
+      aParticle->BestDistance = aSqDist;
+
+      aParticle = aParticles.GetWorstParticle();
+    }
+  }
+  //
+  math_Vector aStep(1, aNbVar);
+  aStep(1) = aStepCT;
+
+  // Find min approximation
+  Standard_Real aValue;
+  math_PSO aPSO(&aFunc, aTinf, aTsup, aStep);
+  aPSO.Perform(aParticles, theNbParticles, aValue, aT);
+  //
+  math_Vector anUV(1, 2);
+  aFunc.QuadricParameters(aT, anUV);
+  if (myS->IsUPeriodic())
+  {
+    if (anUV(1) <  theTUVinf(2) - Precision::PConfusion() || anUV(1)>  theTUVsup(2) + Precision::PConfusion())
+    {
+      anUV(1) = ElCLib::InPeriod(anUV(1), theTUVinf(2), theTUVinf(2) + 2. * M_PI);
+    }
+  }
+  //
+  if (myS->IsVPeriodic())
+  {
+    if (anUV(2) <  theTUVinf(3) - Precision::PConfusion() || anUV(2)>  theTUVsup(3) + Precision::PConfusion())
+    {
+      anUV(2) = ElCLib::InPeriod(anUV(2), theTUVinf(3), theTUVinf(3) + 2. * M_PI);
+    }
+  }
+  //
+  theTUV(1) = aT(1);
+  theTUV(2) = anUV(1);
+  theTUV(3) = anUV(2);
 
-  myDone = Standard_True;
 }
 
 //=======================================================================
diff --git a/src/Extrema/Extrema_GenExtCS.hxx b/src/Extrema/Extrema_GenExtCS.hxx
index d2ca3d5432..7f64f7cffd 100644
--- a/src/Extrema/Extrema_GenExtCS.hxx
+++ b/src/Extrema/Extrema_GenExtCS.hxx
@@ -28,6 +28,7 @@
 #include <Adaptor3d_SurfacePtr.hxx>
 #include <TColgp_HArray2OfPnt.hxx>
 #include <Adaptor3d_CurvePtr.hxx>
+
 class StdFail_NotDone;
 class Standard_OutOfRange;
 class Standard_TypeMismatch;
@@ -112,6 +113,24 @@ private:
   
   Standard_EXPORT Adaptor3d_SurfacePtr BidonSurface() const;
 
+  Standard_EXPORT void GlobMinGenCS(const Adaptor3d_Curve& theC,
+    const Standard_Integer theNbParticles,
+    const math_Vector& theTUVinf,
+    const math_Vector& theTUVsup,
+    math_Vector& theTUV);
+
+  Standard_EXPORT void GlobMinConicS(const Adaptor3d_Curve& theC,
+    const Standard_Integer theNbParticles,
+    const math_Vector& theTUVinf,
+    const math_Vector& theTUVsup,
+    math_Vector& theTUV);
+
+  Standard_EXPORT void GlobMinCQuadric(const Adaptor3d_Curve& theC,
+    const Standard_Integer theNbParticles,
+    const math_Vector& theTUVinf,
+    const math_Vector& theTUVsup,
+    math_Vector& theTUV);
+
 
   Standard_Boolean myDone;
   Standard_Boolean myInit;
diff --git a/src/Extrema/Extrema_GlobOptFuncCQuadric.cxx b/src/Extrema/Extrema_GlobOptFuncCQuadric.cxx
new file mode 100644
index 0000000000..26250f8474
--- /dev/null
+++ b/src/Extrema/Extrema_GlobOptFuncCQuadric.cxx
@@ -0,0 +1,296 @@
+// Copyright (c) 2020 OPEN CASCADE SAS
+//
+// This file is part of Open CASCADE Technology software library.
+//
+// This library is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License version 2.1 as published
+// by the Free Software Foundation, with special exception defined in the file
+// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
+// distribution for complete text of the license and disclaimer of any warranty.
+//
+// Alternatively, this file may be used under the terms of Open CASCADE
+// commercial license or contractual agreement
+
+#include <Extrema_GlobOptFuncCQuadric.hxx>
+
+#include <gp_Pnt.hxx>
+#include <ElSLib.hxx>
+#include <ElCLib.hxx>
+
+
+//=======================================================================
+//function : value
+//purpose  : 
+//=======================================================================
+void Extrema_GlobOptFuncCQuadric::value(Standard_Real ct,
+                                        Standard_Real &F)
+{
+  Standard_Real u, v;
+  //
+  gp_Pnt aCP = myC->Value(ct);
+  switch (mySType)
+  {
+  case GeomAbs_Plane:
+    ElSLib::Parameters(myPln, aCP, u, v);
+    break;
+  case GeomAbs_Cylinder:
+    ElSLib::Parameters(myCylinder, aCP, u, v);
+    break;
+  case GeomAbs_Cone:
+    ElSLib::Parameters(myCone, aCP, u, v);
+    break;
+  case GeomAbs_Sphere:
+    ElSLib::Parameters(mySphere, aCP, u, v);
+    break;
+  case GeomAbs_Torus:
+    ElSLib::Parameters(myTorus, aCP, u, v);
+    break;
+  default:
+    F = Precision::Infinite();
+    return;
+  }
+  //
+  if (mySType != GeomAbs_Plane)
+  {
+    if (myUl > 2. * M_PI + Precision::PConfusion())
+    {
+      u += 2. * M_PI;
+    }
+  }
+  if (mySType == GeomAbs_Torus)
+  {
+    if (myVl > 2. * M_PI + Precision::PConfusion())
+    {
+      v += 2. * M_PI;
+    }
+  }
+
+  F = RealLast();
+  if (u >= myUf && u <= myUl && v >= myVf && v <= myVl)
+  {
+    gp_Pnt aPS = myS->Value(u, v);
+    F = Min(F, aCP.SquareDistance(aPS));
+  }
+  Standard_Integer i;
+  for (i = 0; i < 4; ++i)
+  {
+    F = Min(F, aCP.SquareDistance(myPTrim[i]));
+  }
+}
+
+
+//=======================================================================
+//function : checkInputData
+//purpose  : 
+//=======================================================================
+Standard_Boolean Extrema_GlobOptFuncCQuadric::checkInputData(const math_Vector   &X,
+                                                             Standard_Real       &ct) 
+{
+  ct = X(X.Lower());
+
+  if (ct < myTf || ct > myTl )
+  {
+    return Standard_False;
+  }
+  return Standard_True;
+}
+
+//=======================================================================
+//function : Extrema_GlobOptFuncCQuadric
+//purpose  : Constructor
+//=======================================================================
+Extrema_GlobOptFuncCQuadric::Extrema_GlobOptFuncCQuadric(const Adaptor3d_Curve   *C,
+                                                     const Adaptor3d_Surface *S)
+: myC(C)
+{
+  myTf = myC->FirstParameter();
+  myTl = myC->LastParameter();
+  Standard_Real anUf = S->FirstUParameter(), anUl = S->LastUParameter();
+  Standard_Real aVf = S->FirstVParameter(), aVl = S->LastVParameter();
+  LoadQuad(S, anUf, anUl, aVf, aVl);
+}
+//=======================================================================
+//function : Extrema_GlobOptFuncCQuadric
+//purpose  : Constructor
+//=======================================================================
+Extrema_GlobOptFuncCQuadric::Extrema_GlobOptFuncCQuadric(const Adaptor3d_Curve *C)
+  : myC(C)
+{
+  myTf = myC->FirstParameter();
+  myTl = myC->LastParameter();
+}
+//=======================================================================
+//function : Extrema_GlobOptFuncCQuadric
+//purpose  : Constructor
+//=======================================================================
+Extrema_GlobOptFuncCQuadric::Extrema_GlobOptFuncCQuadric(const Adaptor3d_Curve *C,
+  const Standard_Real theTf, const Standard_Real theTl)
+  : myC(C), myTf(theTf), myTl(theTl)
+{
+}
+
+//=======================================================================
+//function : LoadQuad
+//purpose  : 
+//=======================================================================
+void Extrema_GlobOptFuncCQuadric::LoadQuad( const Adaptor3d_Surface *S, 
+  const Standard_Real theUf, const Standard_Real theUl,
+  const Standard_Real theVf, const Standard_Real theVl)
+{
+  myS = S;
+  myUf = theUf;
+  myUl = theUl;
+  myVf = theVf;
+  myVl = theVl;
+  //
+  if (myS->IsUPeriodic())
+  {
+    Standard_Real aTMax = 2. * M_PI + Precision::PConfusion();
+    if (myUf > aTMax || myUf < -Precision::PConfusion() ||
+      Abs(myUl - myUf) > aTMax)
+    {
+      ElCLib::AdjustPeriodic(0., 2. * M_PI,
+        Min(Abs(myUl - myUf) / 2, Precision::PConfusion()),
+        myUf, myUl);
+    }
+  }
+  if (myS->IsVPeriodic())
+  {
+    Standard_Real aTMax = 2. * M_PI + Precision::PConfusion();
+    if (myVf > aTMax || myVf < -Precision::PConfusion() ||
+      Abs(myVl - myVf) > aTMax)
+    {
+      ElCLib::AdjustPeriodic(0., 2. * M_PI,
+        Min(Abs(myVl - myVf) / 2, Precision::PConfusion()),
+        myVf, myVl);
+    }
+  }
+  myPTrim[0] = myS->Value(myUf, myVf);
+  myPTrim[1] = myS->Value(myUl, myVf);
+  myPTrim[2] = myS->Value(myUl, myVl);
+  myPTrim[3] = myS->Value(myUf, myVl);
+  mySType = S->GetType();
+  switch (mySType)
+  {
+  case GeomAbs_Plane:
+    myPln = myS->Plane();
+    break;
+  case GeomAbs_Cylinder:
+     myCylinder = myS->Cylinder();
+    break;
+  case GeomAbs_Cone:
+    myCone = myS->Cone();
+    break;
+  case GeomAbs_Sphere:
+    mySphere = myS->Sphere();
+    break;
+  case GeomAbs_Torus:
+    myTorus = myS->Torus();
+    break;
+  default:
+    break;
+  }
+
+}
+
+//=======================================================================
+//function : NbVariables
+//purpose  :
+//=======================================================================
+Standard_Integer Extrema_GlobOptFuncCQuadric::NbVariables() const
+{
+  return 1;
+}
+
+//=======================================================================
+//function : Value
+//purpose  :
+//=======================================================================
+Standard_Boolean Extrema_GlobOptFuncCQuadric::Value(const math_Vector &X,
+                                                    Standard_Real     &F)
+{
+  Standard_Real ct;
+  if (!checkInputData(X, ct))
+    return Standard_False;
+
+  value(ct, F);
+  if (Precision::IsInfinite(F))
+  {
+    return Standard_False;
+  }
+  return Standard_True;
+}
+
+//=======================================================================
+//function : QuadricParameters
+//purpose  :
+//=======================================================================
+void Extrema_GlobOptFuncCQuadric::QuadricParameters(const math_Vector& theCT,
+  math_Vector& theUV ) const
+{
+  Standard_Real u, v;
+  //
+  //Arrays of extremity points parameters correspond to array of corner
+  //points  myPTrim[] 
+  Standard_Real uext[4] = { myUf, myUl, myUl, myUf };
+  Standard_Real vext[4] = { myVf, myVf, myVl, myVl };
+  gp_Pnt aCP = myC->Value(theCT(1));
+  switch (mySType)
+  {
+  case GeomAbs_Plane:
+    ElSLib::Parameters(myPln, aCP, u, v);
+    break;
+  case GeomAbs_Cylinder:
+    ElSLib::Parameters(myCylinder, aCP, u, v);
+    break;
+  case GeomAbs_Cone:
+    ElSLib::Parameters(myCone, aCP, u, v);
+    break;
+  case GeomAbs_Sphere:
+    ElSLib::Parameters(mySphere, aCP, u, v);
+    break;
+  case GeomAbs_Torus:
+    ElSLib::Parameters(myTorus, aCP, u, v);
+    break;
+  default:
+    theUV(1) = myUf;
+    theUV(2) = myUl;
+    return;
+  }
+  //
+  if (mySType != GeomAbs_Plane)
+  {
+    if (myUl > 2. * M_PI + Precision::PConfusion())
+    {
+      u += 2. * M_PI;
+    }
+  }
+  if (mySType == GeomAbs_Torus)
+  {
+    if (myVl > 2. * M_PI + Precision::PConfusion())
+    {
+      v += 2. * M_PI;
+    }
+  }
+
+  Standard_Real F = RealLast();
+  if (u >= myUf && u <= myUl && v >= myVf && v <= myVl)
+  {
+    gp_Pnt aPS = myS->Value(u, v);
+    F = aCP.SquareDistance(aPS);
+  }
+  Standard_Integer i;
+  for (i = 0; i < 4; ++i)
+  {
+    Standard_Real Fi = aCP.SquareDistance(myPTrim[i]);
+    if (Fi < F)
+    {
+      F = Fi;
+      u = uext[i];
+      v = vext[i];
+    }
+  }
+  theUV(1) = u;
+  theUV(2) = v;
+}
+
diff --git a/src/Extrema/Extrema_GlobOptFuncCQuadric.hxx b/src/Extrema/Extrema_GlobOptFuncCQuadric.hxx
new file mode 100644
index 0000000000..e4cdb8b5f7
--- /dev/null
+++ b/src/Extrema/Extrema_GlobOptFuncCQuadric.hxx
@@ -0,0 +1,88 @@
+// Copyright (c) 2020 OPEN CASCADE SAS
+//
+// This file is part of Open CASCADE Technology software library.
+//
+// This library is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License version 2.1 as published
+// by the Free Software Foundation, with special exception defined in the file
+// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
+// distribution for complete text of the license and disclaimer of any warranty.
+//
+// Alternatively, this file may be used under the terms of Open CASCADE
+// commercial license or contractual agreement
+
+#ifndef _Extrema_GlobOptFuncCQuadric_HeaderFile
+#define _Extrema_GlobOptFuncCQuadric_HeaderFile
+
+
+#include <Adaptor3d_Curve.hxx>
+#include <Adaptor3d_Surface.hxx>
+#include <math_Matrix.hxx>
+#include <math_Vector.hxx>
+#include <math_MultipleVarFunction.hxx>
+#include <GeomAbs_SurfaceType.hxx>
+#include <gp_Pln.hxx>
+#include <gp_Cylinder.hxx>
+#include <gp_Cone.hxx>
+#include <gp_Sphere.hxx>
+#include <gp_Torus.hxx>
+
+//! This class implements function which calculate square Eucluidean distance
+//! between point on surface and nearest point on Conic.
+class Extrema_GlobOptFuncCQuadric : public math_MultipleVarFunction
+{
+public:
+
+  //! Curve and surface should exist during all the lifetime of Extrema_GlobOptFuncCQuadric.
+  Standard_EXPORT  Extrema_GlobOptFuncCQuadric(const Adaptor3d_Curve *C);
+
+  Standard_EXPORT  Extrema_GlobOptFuncCQuadric(const Adaptor3d_Curve *C, 
+                                               const Standard_Real   theTf, 
+                                               const Standard_Real   theTl);
+
+  Standard_EXPORT  Extrema_GlobOptFuncCQuadric(const Adaptor3d_Curve   *C,
+                                               const Adaptor3d_Surface *S);
+
+  Standard_EXPORT void LoadQuad(const Adaptor3d_Surface *S, 
+                                const Standard_Real     theUf, 
+                                const Standard_Real     theUl,
+                                const Standard_Real     theVf, 
+                                const Standard_Real     theVl);
+
+  Standard_EXPORT virtual Standard_Integer NbVariables() const;
+
+  Standard_EXPORT virtual Standard_Boolean Value(const math_Vector &theX,
+                                                 Standard_Real     &theF);
+  //! Parameters of quadric for point on curve defined by theCT
+  Standard_EXPORT void QuadricParameters(const math_Vector& theCT,
+                                               math_Vector& theUV) const;
+
+private:
+
+  Standard_Boolean checkInputData(const math_Vector   &X,
+                                  Standard_Real       &ct);
+
+  void value(Standard_Real ct,
+             Standard_Real &F);
+
+
+  const Adaptor3d_Curve   *myC;
+  const Adaptor3d_Surface *myS;
+  GeomAbs_SurfaceType mySType;
+  gp_Pln myPln;
+  gp_Cone myCone;
+  gp_Cylinder myCylinder;
+  gp_Sphere mySphere;
+  gp_Torus myTorus;
+  gp_Pnt myPTrim[4];
+  // Boundaries
+  Standard_Real myTf;
+  Standard_Real myTl;
+  Standard_Real myUf;
+  Standard_Real myUl;
+  Standard_Real myVf;
+  Standard_Real myVl;
+
+};
+
+#endif
diff --git a/src/Extrema/Extrema_GlobOptFuncConicS.cxx b/src/Extrema/Extrema_GlobOptFuncConicS.cxx
new file mode 100644
index 0000000000..8ea81b15be
--- /dev/null
+++ b/src/Extrema/Extrema_GlobOptFuncConicS.cxx
@@ -0,0 +1,259 @@
+// Copyright (c) 2020 OPEN CASCADE SAS
+//
+// This file is part of Open CASCADE Technology software library.
+//
+// This library is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License version 2.1 as published
+// by the Free Software Foundation, with special exception defined in the file
+// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
+// distribution for complete text of the license and disclaimer of any warranty.
+//
+// Alternatively, this file may be used under the terms of Open CASCADE
+// commercial license or contractual agreement
+
+#include <Extrema_GlobOptFuncConicS.hxx>
+
+#include <gp_Pnt.hxx>
+#include <ElCLib.hxx>
+
+//F(u, v) = Conic.SquareDistance(myS(u, v))
+
+//=======================================================================
+//function : value
+//purpose  : 
+//=======================================================================
+void Extrema_GlobOptFuncConicS::value(Standard_Real su,
+                                      Standard_Real sv,
+                                      Standard_Real &F)
+{
+  Standard_Real ct;
+  gp_Pnt aPS = myS->Value(su, sv);
+  switch (myCType)
+  {
+  case GeomAbs_Line:
+    ct = ElCLib::Parameter(myLin, aPS);
+    break;
+  case GeomAbs_Circle:
+    ct = ElCLib::Parameter(myCirc, aPS);
+    break;
+  case GeomAbs_Ellipse:
+    ct = ElCLib::Parameter(myElips, aPS);
+    break;
+  case GeomAbs_Hyperbola:
+    ct = ElCLib::Parameter(myHypr, aPS);
+    break;
+  case GeomAbs_Parabola:
+    ct = ElCLib::Parameter(myParab, aPS);
+    break;
+  default:
+    F = Precision::Infinite();
+    return;
+  }
+  //
+  if (myCType == GeomAbs_Circle || myCType == GeomAbs_Ellipse)
+  {
+    if (myTl > 2. * M_PI + Precision::PConfusion())
+    {
+      ct += 2. * M_PI;
+    }
+  }
+  F = RealLast();
+  if (ct >= myTf && ct <= myTl)
+  {
+    gp_Pnt aPC = myC->Value(ct);
+    F = Min(F, aPS.SquareDistance(aPC));
+  }
+  F = Min(F, aPS.SquareDistance(myCPf));
+  F = Min(F, aPS.SquareDistance(myCPl));
+
+}
+
+
+//=======================================================================
+//function : checkInputData
+//purpose  : 
+//=======================================================================
+Standard_Boolean Extrema_GlobOptFuncConicS::checkInputData(const math_Vector   &X,
+                                                           Standard_Real       &su,
+                                                           Standard_Real       &sv)
+{
+  Standard_Integer aStartIndex = X.Lower();
+  su = X(aStartIndex);
+  sv = X(aStartIndex + 1);
+
+  if (su < myUf || su > myUl  ||
+      sv < myVf || sv > myVl)
+  {
+    return Standard_False;
+  }
+  return Standard_True;
+}
+
+//=======================================================================
+//function : Extrema_GlobOptFuncConicS
+//purpose  : Constructor
+//=======================================================================
+Extrema_GlobOptFuncConicS::Extrema_GlobOptFuncConicS(const Adaptor3d_Surface *S,
+  const Standard_Real theUf, const Standard_Real theUl,
+  const Standard_Real theVf, const Standard_Real theVl)
+:  myS(S), myUf(theUf), myUl(theUl),
+   myVf(theVf), myVl(theVl)
+{
+
+}
+
+//=======================================================================
+//function : Extrema_GlobOptFuncConicS
+//purpose  : Constructor
+//=======================================================================
+Extrema_GlobOptFuncConicS::Extrema_GlobOptFuncConicS(const Adaptor3d_Surface *S)
+  : myS(S), myUf(S->FirstUParameter()), myUl(S->LastUParameter()),
+  myVf(S->FirstVParameter()), myVl(S->LastVParameter())
+{
+
+}
+//=======================================================================
+//function : Extrema_GlobOptFuncConicS
+//purpose  : Constructor
+//=======================================================================
+Extrema_GlobOptFuncConicS::Extrema_GlobOptFuncConicS(const Adaptor3d_Curve   *C,
+  const Adaptor3d_Surface *S)
+  : myS(S), myUf(S->FirstUParameter()), myUl(S->LastUParameter()),
+  myVf(S->FirstVParameter()), myVl(S->LastVParameter())
+{
+  Standard_Real aCTf = C->FirstParameter();
+  Standard_Real aCTl = C->LastParameter();
+  LoadConic(C, aCTf, aCTl);
+}
+
+//=======================================================================
+//function : LoadConic
+//purpose  :
+//=======================================================================
+void Extrema_GlobOptFuncConicS::LoadConic(const Adaptor3d_Curve   *C,
+  const Standard_Real theTf, const Standard_Real theTl)
+{
+  myC = C;
+  myTf = theTf;
+  myTl = theTl;
+  if (myC->IsPeriodic())
+  {
+    Standard_Real aTMax = 2. * M_PI + Precision::PConfusion();
+    if (myTf > aTMax || myTf < -Precision::PConfusion() ||
+      Abs(myTl - myTf) > aTMax)
+    {
+      ElCLib::AdjustPeriodic(0., 2. * M_PI,
+        Min(Abs(myTl - myTf) / 2, Precision::PConfusion()),
+        myTf, myTl);
+    }
+  }
+  myCPf = myC->Value(myTf);
+  myCPl = myC->Value(myTl);
+  myCType = myC->GetType();
+  switch (myCType)
+  {
+  case GeomAbs_Line:
+    myLin = myC->Line();
+    break;
+  case GeomAbs_Circle:
+    myCirc = myC->Circle();
+    break;
+  case GeomAbs_Ellipse:
+    myElips = myC->Ellipse();
+    break;
+  case GeomAbs_Hyperbola:
+    myHypr = myC->Hyperbola();
+    break;
+  case GeomAbs_Parabola:
+    myParab = myC->Parabola();
+    break;
+  default:
+    break;
+  }
+}
+
+//=======================================================================
+//function : NbVariables
+//purpose  :
+//=======================================================================
+Standard_Integer Extrema_GlobOptFuncConicS::NbVariables() const
+{
+  return 2;
+}
+
+//=======================================================================
+//function : Value
+//purpose  :
+//=======================================================================
+Standard_Boolean Extrema_GlobOptFuncConicS::Value(const math_Vector &X,
+                                                  Standard_Real     &F)
+{
+  Standard_Real su, sv;
+  if (!checkInputData(X, su, sv))
+    return Standard_False;
+
+  value(su, sv, F);
+  if (Precision::IsInfinite(F))
+  {
+    return Standard_False;
+  }
+  return Standard_True;
+}
+
+//=======================================================================
+//function : ConicParameter
+//purpose  :
+//=======================================================================
+Standard_Real Extrema_GlobOptFuncConicS::ConicParameter(const math_Vector& theUV) const
+{
+  Standard_Real ct;
+  gp_Pnt aPS = myS->Value(theUV(1), theUV(2));
+  switch (myCType)
+  {
+  case GeomAbs_Line:
+    ct = ElCLib::Parameter(myLin, aPS);
+    break;
+  case GeomAbs_Circle:
+    ct = ElCLib::Parameter(myCirc, aPS);
+    break;
+  case GeomAbs_Ellipse:
+    ct = ElCLib::Parameter(myElips, aPS);
+    break;
+  case GeomAbs_Hyperbola:
+    ct = ElCLib::Parameter(myHypr, aPS);
+    break;
+  case GeomAbs_Parabola:
+    ct = ElCLib::Parameter(myParab, aPS);
+    break;
+  default:
+    ct = myTf;
+    return ct;
+  }
+  //
+  if (myCType == GeomAbs_Circle || myCType == GeomAbs_Ellipse)
+  {
+    if (myTl > 2. * M_PI + Precision::PConfusion())
+    {
+      ct += 2. * M_PI;
+    }
+  }
+  Standard_Real F = RealLast();
+  if (ct >= myTf && ct <= myTl)
+  {
+    gp_Pnt aPC = myC->Value(ct);
+    F = Min(F, aPS.SquareDistance(aPC));
+  }
+  Standard_Real Fext = aPS.SquareDistance(myCPf);
+  if (Fext < F)
+  {
+    F = Fext;
+    ct = myTf;
+  }
+  Fext = aPS.SquareDistance(myCPl);
+  if (Fext < F)
+  {
+    F = Fext;
+    ct = myTl;
+  }
+  return ct;
+}
\ No newline at end of file
diff --git a/src/Extrema/Extrema_GlobOptFuncConicS.hxx b/src/Extrema/Extrema_GlobOptFuncConicS.hxx
new file mode 100644
index 0000000000..296cb67029
--- /dev/null
+++ b/src/Extrema/Extrema_GlobOptFuncConicS.hxx
@@ -0,0 +1,90 @@
+
+// Copyright (c) 2020 OPEN CASCADE SAS
+//
+// This file is part of Open CASCADE Technology software library.
+//
+// This library is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License version 2.1 as published
+// by the Free Software Foundation, with special exception defined in the file
+// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
+// distribution for complete text of the license and disclaimer of any warranty.
+//
+// Alternatively, this file may be used under the terms of Open CASCADE
+// commercial license or contractual agreement
+
+#ifndef _Extrema_GlobOptFuncConicS_HeaderFile
+#define _Extrema_GlobOptFuncConicS_HeaderFile
+
+
+#include <Adaptor3d_Curve.hxx>
+#include <Adaptor3d_Surface.hxx>
+#include <math_Matrix.hxx>
+#include <math_Vector.hxx>
+#include <math_MultipleVarFunction.hxx>
+#include <GeomAbs_CurveType.hxx>
+#include <gp_Lin.hxx>
+#include <gp_Circ.hxx>
+#include <gp_Elips.hxx>
+#include <gp_Hypr.hxx>
+#include <gp_Parab.hxx>
+
+//! This class implements function which calculate square Eucluidean distance
+//! between point on surface and nearest point on Conic.
+class Extrema_GlobOptFuncConicS : public math_MultipleVarFunction
+{
+public:
+
+  //! Curve and surface should exist during all the lifetime of Extrema_GlobOptFuncConicS.
+  Standard_EXPORT  Extrema_GlobOptFuncConicS(const Adaptor3d_Curve   *C,
+                                             const Adaptor3d_Surface *S);
+
+  Standard_EXPORT  Extrema_GlobOptFuncConicS(const Adaptor3d_Surface *S);
+
+  Standard_EXPORT  Extrema_GlobOptFuncConicS(const Adaptor3d_Surface *S,
+                                             const Standard_Real     theUf, 
+                                             const Standard_Real     theUl,
+                                             const Standard_Real     theVf, 
+                                             const Standard_Real     theVl);
+
+  Standard_EXPORT void LoadConic(const Adaptor3d_Curve *S, const Standard_Real theTf, const Standard_Real theTl);
+
+  Standard_EXPORT virtual Standard_Integer NbVariables() const;
+
+  Standard_EXPORT virtual Standard_Boolean Value(const math_Vector &theX,
+                                                 Standard_Real     &theF);
+
+  //! Parameter of conic for point on surface defined by theUV
+  Standard_EXPORT Standard_Real ConicParameter(const math_Vector& theUV) const;
+
+private:
+
+  Standard_Boolean checkInputData(const math_Vector   &X,
+                                  Standard_Real       &su,
+                                  Standard_Real       &sv);
+
+  void value(Standard_Real su,
+             Standard_Real sv,
+             Standard_Real &F);
+
+
+  const Adaptor3d_Curve   *myC;
+  const Adaptor3d_Surface *myS;
+  GeomAbs_CurveType myCType;
+  gp_Lin myLin;
+  gp_Circ myCirc;
+  gp_Elips myElips;
+  gp_Hypr myHypr;
+  gp_Parab myParab;
+  gp_Pnt myCPf;
+  gp_Pnt myCPl;
+  //Boundaries
+  Standard_Real myTf;
+  Standard_Real myTl;
+  Standard_Real myUf;
+  Standard_Real myUl;
+  Standard_Real myVf;
+  Standard_Real myVl;
+
+};
+
+#endif
diff --git a/src/Extrema/FILES b/src/Extrema/FILES
index 34ec6a72e0..1e3d13ee43 100644
--- a/src/Extrema/FILES
+++ b/src/Extrema/FILES
@@ -99,6 +99,10 @@ Extrema_GlobOptFuncCC.cxx
 Extrema_GlobOptFuncCC.hxx
 Extrema_GlobOptFuncCS.cxx
 Extrema_GlobOptFuncCS.hxx
+Extrema_GlobOptFuncConicS.cxx
+Extrema_GlobOptFuncConicS.hxx
+Extrema_GlobOptFuncCQuadric.cxx
+Extrema_GlobOptFuncCQuadric.hxx
 Extrema_GLocateExtPC.gxx
 Extrema_HArray1OfPOnCurv.hxx
 Extrema_HArray1OfPOnCurv2d.hxx
diff --git a/src/math/math_PSOParticlesPool.cxx b/src/math/math_PSOParticlesPool.cxx
index f3b7bf6ca6..8fd5dc28cb 100644
--- a/src/math/math_PSOParticlesPool.cxx
+++ b/src/math/math_PSOParticlesPool.cxx
@@ -31,7 +31,7 @@ math_PSOParticlesPool::math_PSOParticlesPool(const Standard_Integer theParticles
 {
   myParticlesCount = theParticlesCount;
   myDimensionCount = theDimensionCount;
-
+  myMemory.Init(0.);
   // Pointers adjusting.
   Standard_Integer aParIdx, aShiftIdx;
   for(aParIdx = 1; aParIdx <= myParticlesCount; ++aParIdx)
diff --git a/tests/bugs/modalg_5/bug25232_8 b/tests/bugs/modalg_5/bug25232_8
index 49d0e7f63a..61892b8be4 100644
--- a/tests/bugs/modalg_5/bug25232_8
+++ b/tests/bugs/modalg_5/bug25232_8
@@ -27,5 +27,5 @@ mkvolume result fcon3 fp
 checkprops result -s 1706.51 
 checkshape result
 
-checknbshapes result -vertex 4 -edge 5 -wire 2 -face 2 -shell 1 -solid 1 -compsolid 0 -compound 0 -shape 15
+checknbshapes result -vertex 5 -edge 6 -wire 2 -face 2 -shell 1 -solid 1 -compsolid 0 -compound 0 -shape 17
 checkview -display result -2d -path ${imagedir}/${test_image}.png
diff --git a/tests/bugs/modalg_7/bug27928 b/tests/bugs/modalg_7/bug27928
index d48df7980e..24073c9b6c 100644
--- a/tests/bugs/modalg_7/bug27928
+++ b/tests/bugs/modalg_7/bug27928
@@ -36,7 +36,7 @@ checkprops r2 -s 2075.44 -v 1489.33
 checknbshapes r3 -wire 5 -face 5 -shell 1 -solid 1
 checkprops r3 -s 2521.83 -v 1824.69
 
-checknbshapes r4 -vertex 12 -edge 18 -t
+checknbshapes r4 -vertex 13 -edge 19 -t
 checkprops r4 -l 825.645
 
 checkview -display r0 -2d -path ${imagedir}/${test_image}.png
diff --git a/tests/bugs/modalg_7/bug29580_1 b/tests/bugs/modalg_7/bug29580_1
index 260b75ebc2..010433c134 100644
--- a/tests/bugs/modalg_7/bug29580_1
+++ b/tests/bugs/modalg_7/bug29580_1
@@ -9,6 +9,7 @@ puts ""
 restore [locate_data_file bug29580_Cylinder.brep] b1
 restore [locate_data_file bug29580_Solid.brep] b2
 
+settolerance b2 e 1.e-5
 bfuse result b1 b2
 
 foreach f [explode result f] {
@@ -21,7 +22,7 @@ foreach f [explode result f] {
 }
 
 checkshape result
-checknbshapes result -wire 11 -face 10 -shell 1 -solid 1
-checkprops result -s 865.851 -v 1622.17
+checknbshapes result -wire 14 -face 13 -shell 1 -solid 1
+checkprops result -s 866.155 -v 1622.85
 
 checkview -display result -2d -path ${imagedir}/${test_image}.png
diff --git a/tests/bugs/modalg_7/bug29839 b/tests/bugs/modalg_7/bug29839
new file mode 100644
index 0000000000..3b0d828bcb
--- /dev/null
+++ b/tests/bugs/modalg_7/bug29839
@@ -0,0 +1,22 @@
+puts "================================================================="
+puts "OCC29839: Unexpected extrema behavior"
+puts "================================================================="
+puts ""
+
+restore [locate_data_file bug29839.brep] s
+
+explode s
+distmini d s_1 s_2
+checknbshapes d -edge 0 -vertex 1
+
+set dist [dval d_val]
+
+if { ${dist} > 2.e-10} {
+   puts "Error: bad distance"
+}
+
+smallview  +X+Y
+donly s_1 s_2 d
+fit
+
+checkview -screenshot -2d -path ${imagedir}/${test_image}.png