Blend_CSWalking::Blend_CSWalking(const TheCurve& Curv,
				 const TheSurface& Surf,
				 const Handle(TheTopolTool)& Domain):
       done(Standard_False),surf(Surf),
       curv(Curv)
{
  domain = Domain;
}



void Blend_CSWalking::Perform(Blend_CSFunction& Func,
//			      Blend_CSFuncInv& FuncInv,
			      const Standard_Real Pdep,   
			      const Standard_Real Pmax,
			      const Standard_Real MaxStep,
			      const Standard_Real TolGuide,
			      const math_Vector& ParDep,
			      const Standard_Real Tolesp,
			      const Standard_Real Fleche,
			      const Standard_Boolean Appro)
{

  done = Standard_False;
  iscomplete = Standard_False;
  comptra = Standard_False;
  line = new TheLine ();
  Standard_Integer Nbvar = Func.NbVariables();
  tolesp = Abs(Tolesp);
  tolgui = Abs(TolGuide);
  fleche = Abs(Fleche);
  rebrou = Standard_False;
  pasmax = Abs(MaxStep);
  math_Vector sol(1,Nbvar);

  firstsol = new TColStd_HArray1OfReal(1,Nbvar);

  if (Pmax-Pdep >= 0.) {
    sens = 1.;
  }
  else {
    sens = -1.;
  }

  Blend_Status State;
  TheExtremity ptf1,ptf2;

  param = Pdep;
  firstparam = Pdep;
  Func.Set(param);

  if (Appro) {

    TopAbs_State situ;
//    math_Vector tolerance(1,3),infbound(1,3),supbound(1,3);
    math_Vector tolerance(1,Nbvar),infbound(1,Nbvar),supbound(1,Nbvar);
    Func.GetTolerance(tolerance,tolesp);
    Func.GetBounds(infbound,supbound);
    math_FunctionSetRoot rsnld(Func,tolerance,30);

    rsnld.Perform(Func,ParDep,infbound,supbound);
    
    if (!rsnld.IsDone()) {
      return;
    }
    rsnld.Root(sol);

//    situ1 = TheTopolTool::Classify(surf1,gp_Pnt2d(sol(1),sol(2)),
//				   Max(tolerance(1),tolerance(2)));
//    situ2 = TheTopolTool::Classify(surf2,gp_Pnt2d(sol(3),sol(4)),
//				   Max(tolerance(3),tolerance(4)));
/*
    situ = domain->Classify(gp_Pnt2d(sol(1),sol(2)),
			      Min(tolerance(1),tolerance(2)));
*/
    situ = domain->Classify(Func.Pnt2d(),
			    Min(tolerance(1),tolerance(2)));

    if (situ != TopAbs_IN ) {
      return;
    }
  }
  else {
    sol = ParDep;
  }

  for (Standard_Integer i=1; i<= Nbvar; i++) {
    firstsol->ChangeValue(i) = sol(i);
  }
  State = TestArret(Func,sol,Standard_False,Blend_OK);
  if (State!=Blend_OK) {
    return;
  }
#ifdef DEB
  if (Blend_GettraceDRAWSECT()){
    Drawsect(surf,curv,param,Func);
  }
#endif
  // Mettre a jour la ligne.
  line->Append(previousP);
  Standard_Real U,V,W;
  previousP.ParametersOnS(U,V);
  W = previousP.ParameterOnC();
  TheExtremity P1(previousP.PointOnS(),U,V,previousP.Parameter(),tolesp);
  TheExtremity P2(previousP.PointOnC(),W,previousP.Parameter(),tolesp);
  if (sens>0.) {
    line->SetStartPoints(P1,P2);
  }
  else {
    line->SetEndPoints(P1,P2);
  }

//  InternalPerform(Func,FuncInv,Pmax);
  InternalPerform(Func,sol,Pmax);

  done = Standard_True;
}



Standard_Boolean Blend_CSWalking::Complete(Blend_CSFunction& Func,
//					   Blend_CSFuncInv& FuncInv,
					   const Standard_Real Pmin)
{
  if (!done) {StdFail_NotDone::Raise();}
  if (iscomplete) {return Standard_True;}

/*
  if (sens >0.) {
    previousP = line->Point(1);
  }
  else {
    previousP = line->Point(line->NbPoints());
  }
*/

  sens = -sens;
/*
  param = previousP.Parameter();
  previousP.ParametersOnS(sol(1),sol(2));
  sol(3) = previousP.ParameterOnC();
*/
  Standard_Integer Nbvar = Func.NbVariables();
  math_Vector sol(1,Nbvar);
  for (Standard_Integer i =1; i<= Nbvar; i++) {
    sol(i) = firstsol->Value(i);
  }

  param = firstparam;

//  InternalPerform(Func,FuncInv,Pmin);
  InternalPerform(Func,sol,Pmin);

  sens = -sens;
  iscomplete = Standard_True;
  return Standard_True;
}