OCCT

// Created on: 1996-03-12
// Created by: Bruno DUMORTIER
// Copyright (c) 1995-1999 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 <Geom2d_BezierCurve.hxx>
#include <Geom2d_BSplineCurve.hxx>
#include <Geom2dConvert_BSplineCurveToBezierCurve.hxx>
#include <Standard_DomainError.hxx>
#include <Standard_OutOfRange.hxx>
#include <gp_Pnt2d.hxx>
#include <NCollection_Array1.hxx>

//=================================================================================================

Geom2dConvert_BSplineCurveToBezierCurve::Geom2dConvert_BSplineCurveToBezierCurve(
  const occ::handle<Geom2d_BSplineCurve>& BasisCurve)
{
  myCurve = occ::down_cast<Geom2d_BSplineCurve>(BasisCurve->Copy());
  // periodic curve can't be converted correctly by two main reasons:
  // last pole (equal to first one) is missing;
  // poles recomputation using default boor scheme is fails.
  if (myCurve->IsPeriodic())
  {
    myCurve->SetNotPeriodic();
  }
  double Uf = myCurve->FirstParameter();
  double Ul = myCurve->LastParameter();
  myCurve->Segment(Uf, Ul);
  myCurve->IncreaseMultiplicity(myCurve->FirstUKnotIndex(),
                                myCurve->LastUKnotIndex(),
                                myCurve->Degree());
}

//=================================================================================================

Geom2dConvert_BSplineCurveToBezierCurve::Geom2dConvert_BSplineCurveToBezierCurve(
  const occ::handle<Geom2d_BSplineCurve>& BasisCurve,
  const double                            U1,
  const double                            U2,
  const double                            ParametricTolerance)
{
  if (U2 - U1 < ParametricTolerance)
  {
    throw Standard_DomainError("GeomConvert_BSplineCurveToBezierSurface");
  }

  double Uf = U1, Ul = U2;
  double PTol = ParametricTolerance / 2;

  int I1, I2;
  myCurve = occ::down_cast<Geom2d_BSplineCurve>(BasisCurve->Copy());
  if (myCurve->IsPeriodic())
  {
    myCurve->SetNotPeriodic();
  }

  myCurve->LocateU(U1, PTol, I1, I2);
  if (I1 == I2)
  { // We are on the knot
    if (myCurve->Knot(I1) > U1)
    {
      Uf = myCurve->Knot(I1);
    }
  }

  myCurve->LocateU(U2, PTol, I1, I2);
  if (I1 == I2)
  { // We are on the knot
    if (myCurve->Knot(I1) < U2)
    {
      Ul = myCurve->Knot(I1);
    }
  }

  myCurve->Segment(Uf, Ul);
  myCurve->IncreaseMultiplicity(myCurve->FirstUKnotIndex(),
                                myCurve->LastUKnotIndex(),
                                myCurve->Degree());
}

//=================================================================================================

occ::handle<Geom2d_BezierCurve> Geom2dConvert_BSplineCurveToBezierCurve::Arc(const int Index)
{
  if (Index < 1 || Index > myCurve->NbKnots() - 1)
  {
    throw Standard_OutOfRange("Geom2dConvert_BSplineCurveToBezierCurve");
  }
  int Deg = myCurve->Degree();

  NCollection_Array1<gp_Pnt2d> Poles(1, Deg + 1);

  occ::handle<Geom2d_BezierCurve> C;
  if (myCurve->IsRational())
  {
    NCollection_Array1<double> Weights(1, Deg + 1);
    for (int i = 1; i <= Deg + 1; i++)
    {
      Poles(i)   = myCurve->Pole(i + Deg * (Index - 1));
      Weights(i) = myCurve->Weight(i + Deg * (Index - 1));
    }
    C = new Geom2d_BezierCurve(Poles, Weights);
  }
  else
  {
    for (int i = 1; i <= Deg + 1; i++)
    {
      Poles(i) = myCurve->Pole(i + Deg * (Index - 1));
    }
    C = new Geom2d_BezierCurve(Poles);
  }
  return C;
}

//=================================================================================================

void Geom2dConvert_BSplineCurveToBezierCurve::Arcs(
  NCollection_Array1<occ::handle<Geom2d_BezierCurve>>& Curves)
{
  int n = NbArcs();
  for (int i = 1; i <= n; i++)
  {
    Curves(i) = Arc(i);
  }
}

//=================================================================================================

void Geom2dConvert_BSplineCurveToBezierCurve::Knots(NCollection_Array1<double>& TKnots) const
{
  int ii, kk;
  for (ii = 1, kk = TKnots.Lower(); ii <= myCurve->NbKnots(); ii++, kk++)
  {
    TKnots(kk) = myCurve->Knot(ii);
  }
}

//=================================================================================================

int Geom2dConvert_BSplineCurveToBezierCurve::NbArcs() const
{
  return (myCurve->NbKnots() - 1);
}