// File:	IntCurveSurface_Polygon.gxx
// Created:	Mon Oct 12 17:17:30 1992
// Author:	Laurent BUCHARD
//		<lbr@sdsun2>



#include <Standard_ConstructionError.hxx>
#include <Bnd_Box.hxx>
#include <TColgp_Array1OfPnt.hxx>
#include <gp_Lin.hxx>
#include <gp_Vec.hxx>
#include <gp_Dir.hxx>


//======================================================================
//== On echantillonne sur le Domain de la Curve  NbPts Points 
//== a parametres constants.
//== 
//== On estime la fleche maximum en prenant la distance maxi entre la 
//== droite Curve.Value(X(i))-->Curve.Value(X(i+1)) 
//== et le point Curve.Value(X(i+1/2))
//======================================================================
IntCurveSurface_Polygon::IntCurveSurface_Polygon(const TheCurve&        C,
						 const Standard_Integer tNbPts):
       ThePnts(1,(tNbPts<5)? 5 : tNbPts) 
{ 
  Standard_Integer NbPts = (tNbPts<5)? 5 : tNbPts;
  NbPntIn = NbPts;
  Binf = TheCurveTool::FirstParameter(C);
  Bsup = TheCurveTool::LastParameter(C);
  Init(C); 
}



IntCurveSurface_Polygon::IntCurveSurface_Polygon(const TheCurve&        C,
						 const Standard_Real    U1,
						 const Standard_Real    U2,
						 const Standard_Integer tNbPts):
       ThePnts(1,(tNbPts<5)? 5 : tNbPts) , Binf(U1) , Bsup(U2)
{ 
  
  
  Standard_Integer NbPts = (tNbPts<5)? 5 : tNbPts;
  NbPntIn = NbPts;
  Init(C);
}

//=======================================================================
//function : IntCurveSurface_Polygon
//purpose  : 
//=======================================================================

IntCurveSurface_Polygon::IntCurveSurface_Polygon(const TheCurve&        C,
						 const TColStd_Array1OfReal& Upars):
       ThePnts(1,Upars.Length()) , Binf(Upars(Upars.Lower())) , Bsup(Upars(Upars.Upper()))
{ 
  
  //ddout << "IntCurveSurface_Polygon::IntCurveSurface_Polygon" << endl;
  Standard_Integer NbPts = Upars.Length();
  //ddout << "NbPts :" << NbPts << endl;
  NbPntIn = NbPts;
  Init(C, Upars);
}


void IntCurveSurface_Polygon::Init(const TheCurve&        C) { 
  
  Standard_Real u=Binf; 
  Standard_Real u1=Bsup;
  Standard_Real du=(u1-u)/(Standard_Real)(NbPntIn-1);
  Standard_Integer i=1;
  gp_Pnt P;
  do {
    TheCurveTool::D0(C,u,P);
    TheBnd.Add(P);
    ThePnts.SetValue(i,P);             
    u+=du;
    i++;
  }
  while(i<=NbPntIn);


  //-----------------------------------------------------
  //--- Calcul d un majorant de fleche approche
  //---
  TheDeflection = 0.0;

  if(NbPntIn>3) { 
    
    i=1;
    u=Binf;
    u+=du * 0.5;
    
    do {
      gp_Pnt Pm=TheCurveTool::Value(C,u);
      gp_Pnt P1=ThePnts.Value(i);
      gp_Pnt P2=ThePnts.Value(i+1);
      gp_Lin L(P1,gp_Dir(gp_Vec(P1,P2)));
      Standard_Real t=L.Distance(Pm);
      
      if(t>TheDeflection) {
	TheDeflection = t;
      }
      u+=du;
      i++;
    }
    while(i<NbPntIn);
    
    TheBnd.Enlarge(1.5*TheDeflection);
  }
  else { 
    TheBnd.Enlarge(1e-10);
  }
  ClosedPolygon = Standard_False;
}

//=======================================================================
//function : Init
//purpose  : 
//=======================================================================

void IntCurveSurface_Polygon::Init(const TheCurve&        C,
				   const TColStd_Array1OfReal& Upars) { 

  //ddout << "IntCurveSurface_Polygon::Init" << endl;
  Standard_Real u=Binf; 
  Standard_Real u1=Bsup;
  Standard_Integer i=1, i0 = Upars.Lower()-1;
  gp_Pnt P;

  myParams = new TColStd_HArray1OfReal(1, Upars.Length());
  do {
    //ddout << "-------------Parameter : " << i << " " << Upars(i+i0) << endl;
    myParams->SetValue(i, Upars(i+i0));
    TheCurveTool::D0(C,Upars(i+i0),P);
    //ddout << "P : " << P.X() << " " << P.Y() << " " << P.Z() << endl;
    TheBnd.Add(P);
    ThePnts.SetValue(i,P);             
    i++;
  }
  while(i<=NbPntIn);


  //-----------------------------------------------------
  //--- Calcul d un majorant de fleche approche
  //---
  TheDeflection = 0.0;

  if(NbPntIn>3) { 
    
    i=1;
    //ddout << "Deflection estimation" << endl;
    do {
      u = 0.5*(Upars(i0+i)+Upars(i0+i+1));
      //ddout << "===========Parameter : " << i << " " << u << endl;
      gp_Pnt Pm=TheCurveTool::Value(C,u);
      //ddout << "Pm : " << Pm.X() << " " << Pm.Y() << " " << Pm.Z() << endl;
      gp_Pnt P1=ThePnts.Value(i);
      //ddout << "P1 : " << P1.X() << " " << P1.Y() << " " << P1.Z() << endl;
      gp_Pnt P2=ThePnts.Value(i+1);
      //ddout << "P2 : " << P2.X() << " " << P2.Y() << " " << P2.Z() << endl;
      gp_Lin L(P1,gp_Dir(gp_Vec(P1,P2)));
      Standard_Real t=L.Distance(Pm);
      //ddout << "Distance " << t << endl;
      if(t>TheDeflection) {
	TheDeflection = t;
      }
      i++;
    }
    while(i<NbPntIn);
    //ddout << " TheDeflection = " << TheDeflection << endl;
    TheBnd.Enlarge(1.5*TheDeflection);
  }
  else { 
    TheBnd.Enlarge(1e-10);
  }
  ClosedPolygon = Standard_False;
}


//======================================================================
Standard_Real IntCurveSurface_Polygon::ApproxParamOnCurve(const Standard_Integer TheIndex,
							  const Standard_Real    TheParamOnLine) const
{
  //ddout << "IntCurveSurface_Polygon::ApproxParamOnCurve" << endl;
  if(TheParamOnLine < 0.0 || TheParamOnLine >1.0) { 
    cout<<" ParamOnLine  =  "<<TheParamOnLine<<"  avec Index = "
      <<TheIndex<<"  dans IntCurveSurface_Polygon::ApproxParamOnCurve"<<endl;
    return(Binf+(TheParamOnLine*(Bsup-Binf))/(Standard_Real)(NbPntIn-1));
  }

  Standard_Integer Index = TheIndex;
  Standard_Real    ParamOnLine = TheParamOnLine;
  if (Index > NbPntIn) {
    cout << "OutOfRange Polygon::ApproxParamOnCurve " <<endl;
  }
  if((Index == NbPntIn) && (ParamOnLine == 0.0)) { 
    Index--; ParamOnLine=1.0;
  }

  Standard_Real du, u;
  if (myParams.IsNull())
    {
      du = (Bsup-Binf)/(Standard_Real)(NbPntIn-1);
      u  = Binf + du * (Standard_Real)(Index-1);
    }
  else
    {
      du = myParams->Value(Index+1) - myParams->Value(Index);
      u  = myParams->Value(Index);
    }

  u += du * ParamOnLine;
  return (u);
}
 

//======================================================================
void IntCurveSurface_Polygon::Dump(void) const {
#if 0  
  static Standard_Integer Compteur=0;
  char tamp[100];
  Compteur++;
  sprintf(tamp,"Poly%d",Compteur);
  cout<<"  @@@@@@@@@@@ F i c h i e r   :   "<<tamp<<" @@@@@@@@@@"<<endl;
  FILE *fp;
  fp=fopen(tamp,"w");
  if(fp==NULL) {
    cout<<"PolyGonGen::Erreur en Ouverture Fichier"<<tamp<<endl;
    return;
  }
  fprintf(fp,"\n#Discretisation de : %f ---> %f \n",Binf,Bsup);
  fprintf(fp,"\npol %d %d %f",Compteur,NbPntIn,TheDeflection);
  gp_Pnt p1,p2;
  for (Standard_Integer iObje=1; iObje<=NbSegments(); iObje++) {
    p1=BeginOfSeg(iObje);
    fprintf(fp,"\npnt %d %f %f",Compteur,p1.X(),p1.Y());
  }
  p1=EndOfSeg(NbSegments());
  fprintf(fp,"\npnt %d %f %f",Compteur,p1.X(),p1.Y());
  fprintf(fp,"\ndispol %d\n#\n",Compteur);
  fclose(fp);
#endif
}
//======================================================================
//======================================================================