OCCT

// Copyright (c) 2025 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 <GeomBndLib_Cone.hxx>

#include <ElSLib.hxx>
#include <GeomBndLib_Circle.hxx>
#include <GeomBndLib_InfiniteHelpers.pxx>
#include <gp_Circ.hxx>
#include <gp_Cone.hxx>
#include <Precision.hxx>
#include <Standard_Failure.hxx>

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

//! Compute bounding box for a finite cone patch.
static void computeCone(const gp_Cone& theCone,
                        const double   theUMin,
                        const double   theUMax,
                        const double   theVMin,
                        const double   theVMax,
                        Bnd_Box&       theBox)
{
  const gp_Ax3& aPos  = theCone.Position();
  const double  aR    = theCone.RefRadius();
  const double  aSAng = theCone.SemiAngle();

  // Add circle at VMin.
  gp_Circ aC = ElSLib::ConeVIso(aPos, aR, aSAng, theVMin);
  if (aC.Radius() > Precision::Confusion())
  {
    theBox.Add(GeomBndLib_Circle::Box(aC, theUMin, theUMax, 0.));
  }
  else
  {
    theBox.Add(aC.Location());
  }

  // Add circle at VMax.
  aC = ElSLib::ConeVIso(aPos, aR, aSAng, theVMax);
  if (aC.Radius() > Precision::Confusion())
  {
    theBox.Add(GeomBndLib_Circle::Box(aC, theUMin, theUMax, 0.));
  }
  else
  {
    theBox.Add(aC.Location());
  }
}

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

Bnd_Box GeomBndLib_Cone::Box(double theTol) const
{
  double aU1, aU2, aV1, aV2;
  myGeom->Bounds(aU1, aU2, aV1, aV2);
  return Box(aU1, aU2, aV1, aV2, theTol);
}

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

Bnd_Box GeomBndLib_Cone::Box(double theUMin,
                             double theUMax,
                             double theVMin,
                             double theVMax,
                             double theTol) const
{
  Bnd_Box       aBox;
  const gp_Cone aCone = myGeom->Cone();
  const gp_Dir& aDir  = aCone.Axis().Direction();

  if (Precision::IsNegativeInfinite(theVMin))
  {
    if (Precision::IsNegativeInfinite(theVMax))
    {
      throw Standard_Failure("GeomBndLib_Cone::Box - bad parameter");
    }
    else if (Precision::IsPositiveInfinite(theVMax))
    {
      // Fully infinite V: add the circle at V=0 to give the box finite radial extent.
      const gp_Circ aC =
        ElSLib::ConeVIso(aCone.Position(), aCone.RefRadius(), aCone.SemiAngle(), 0.);
      if (aC.Radius() > Precision::Confusion())
      {
        aBox.Add(GeomBndLib_Circle::Box(aC, theUMin, theUMax, 0.));
      }
      else
      {
        aBox.Add(aC.Location());
      }
      GeomBndLib_InfiniteHelpers::OpenMinMax(aDir, aBox);
    }
    else
    {
      computeCone(aCone, theUMin, theUMax, 0., theVMax, aBox);
      GeomBndLib_InfiniteHelpers::OpenMin(aDir, aBox);
    }
  }
  else if (Precision::IsPositiveInfinite(theVMin))
  {
    if (Precision::IsNegativeInfinite(theVMax))
    {
      // Reversed infinite V: add the circle at V=0 to give the box finite radial extent.
      const gp_Circ aC =
        ElSLib::ConeVIso(aCone.Position(), aCone.RefRadius(), aCone.SemiAngle(), 0.);
      if (aC.Radius() > Precision::Confusion())
      {
        aBox.Add(GeomBndLib_Circle::Box(aC, theUMin, theUMax, 0.));
      }
      else
      {
        aBox.Add(aC.Location());
      }
      GeomBndLib_InfiniteHelpers::OpenMinMax(aDir, aBox);
    }
    else if (Precision::IsPositiveInfinite(theVMax))
    {
      throw Standard_Failure("GeomBndLib_Cone::Box - bad parameter");
    }
    else
    {
      computeCone(aCone, theUMin, theUMax, 0., theVMax, aBox);
      GeomBndLib_InfiniteHelpers::OpenMax(aDir, aBox);
    }
  }
  else
  {
    if (Precision::IsNegativeInfinite(theVMax))
    {
      computeCone(aCone, theUMin, theUMax, theVMin, 0., aBox);
      GeomBndLib_InfiniteHelpers::OpenMin(aDir, aBox);
    }
    else if (Precision::IsPositiveInfinite(theVMax))
    {
      computeCone(aCone, theUMin, theUMax, theVMin, 0., aBox);
      GeomBndLib_InfiniteHelpers::OpenMax(aDir, aBox);
    }
    else
    {
      computeCone(aCone, theUMin, theUMax, theVMin, theVMax, aBox);
    }
  }

  aBox.Enlarge(theTol);
  return aBox;
}