// Created on: 1994-04-05
// Created by: Yves FRICAUD
// Copyright (c) 1994-1999 Matra Datavision
// Copyright (c) 1999-2014 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 <Bisector_FunctionH.hxx>
#include <Geom2d_Curve.hxx>
#include <gp_Pnt2d.hxx>
#include <gp_Vec2d.hxx>

//=============================================================================
//function :
// purpose :
//=============================================================================
Bisector_FunctionH::Bisector_FunctionH (const Handle(Geom2d_Curve)& C2,
					const gp_Pnt2d&             P1,
					const gp_Vec2d&             T1)
     :p1(P1),t1(T1)
{
  t1.Normalize();
  curve2 = C2;
}

//=============================================================================
//function : Value
// purpose :
//                F = P1P2.(||T2||T1 + T2)
//=============================================================================
Standard_Boolean Bisector_FunctionH::Value (const Standard_Real  X,
					          Standard_Real& F)
{
  gp_Pnt2d P2  ;      // point sur C2. 
  gp_Vec2d T2  ;      // tangente a C2 en V.
  curve2->D1(X,P2,T2);  

  Standard_Real NormT2 = T2.Magnitude();
  Standard_Real Ax     = NormT2*t1.X() - T2.X();
  Standard_Real Ay     = NormT2*t1.Y() - T2.Y();

  F = (p1.X() - P2.X())*Ax + (p1.Y() - P2.Y())*Ay;

  return Standard_True;
}

//=============================================================================
//function : Derivative
// purpose :
//=============================================================================
Standard_Boolean Bisector_FunctionH::Derivative(const Standard_Real  X,
						      Standard_Real& D)
{
  Standard_Real F;
  return Values (X,F,D);
}

//=============================================================================
//function : Values
// purpose :
//=============================================================================
Standard_Boolean Bisector_FunctionH::Values (const Standard_Real  X,
					           Standard_Real& F,
					           Standard_Real& D)
{
  gp_Pnt2d P2  ;      // point sur C2. 
  gp_Vec2d T2  ;      // tangente a C2 en V.
  gp_Vec2d T2v ;      // derivee seconde a C2 en V.

  curve2->D2(X,P2,T2,T2v); 
 
  Standard_Real NormT2 = T2.Magnitude();
  Standard_Real Ax     = NormT2*t1.X() - T2.X();
  Standard_Real Ay     = NormT2*t1.Y() - T2.Y();

  F = (p1.X() - P2.X())*Ax + (p1.Y() - P2.Y())*Ay;

  Standard_Real Scal = T2.Dot(T2v)/NormT2;
  Standard_Real dAx  = Scal*t1.X() - T2v.X();
  Standard_Real dAy  = Scal*t1.Y() - T2v.Y();
  
  D = - T2.X()*Ax - T2.Y()*Ay + (p1.X() - P2.X())*dAx + (p1.Y() - P2.Y())*dAy;
  

  return Standard_True;

}