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.

#ifndef _GeomHash_SurfaceOfRevolutionHasher_HeaderFile
#define _GeomHash_SurfaceOfRevolutionHasher_HeaderFile

#include <Standard_HashUtils.hxx>
#include <Geom_SurfaceOfRevolution.hxx>
#include <GeomHash_PointHasher.pxx>
#include <GeomHash_DirectionHasher.pxx>
#include <GeomHash_CurveHasher.hxx>
#include <Precision.hxx>

//! OCCT-style hasher for Geom_SurfaceOfRevolution.
//! Used for geometry deduplication.
struct GeomHash_SurfaceOfRevolutionHasher
{
  double CompTolerance;
  double HashTolerance;

  GeomHash_SurfaceOfRevolutionHasher(double theCompTolerance = Precision::Angular(),
                                     double theHashTolerance = Precision::Confusion())
      : CompTolerance(theCompTolerance),
        HashTolerance(theHashTolerance)
  {
  }

  // Hashes the revolution surface by its axis and basis curve.
  std::size_t operator()(const occ::handle<Geom_SurfaceOfRevolution>& theSurface) const noexcept
  {
    const GeomHash_PointHasher     aPointHasher(CompTolerance, HashTolerance);
    const GeomHash_DirectionHasher aDirHasher(CompTolerance, HashTolerance);
    const GeomHash_CurveHasher     aCurveHasher{CompTolerance, HashTolerance};

    const gp_Ax1&     anAxis     = theSurface->Axis();
    const std::size_t aHashes[3] = {aCurveHasher(theSurface->BasisCurve()),
                                    aPointHasher(anAxis.Location()),
                                    aDirHasher(anAxis.Direction())};
    return opencascade::hashBytes(aHashes, sizeof(aHashes));
  }

  // Compares two revolution surfaces.
  bool operator()(const occ::handle<Geom_SurfaceOfRevolution>& theSurface1,
                  const occ::handle<Geom_SurfaceOfRevolution>& theSurface2) const noexcept
  {
    const GeomHash_PointHasher     aPointHasher(CompTolerance, HashTolerance);
    const GeomHash_DirectionHasher aDirHasher(CompTolerance, HashTolerance);
    const GeomHash_CurveHasher     aCurveHasher{CompTolerance, HashTolerance};

    const gp_Ax1& anAxis1 = theSurface1->Axis();
    const gp_Ax1& anAxis2 = theSurface2->Axis();

    return aCurveHasher(theSurface1->BasisCurve(), theSurface2->BasisCurve())
           && aPointHasher(anAxis1.Location(), anAxis2.Location())
           && aDirHasher(anAxis1.Direction(), anAxis2.Direction());
  }
};

#endif // _GeomHash_SurfaceOfRevolutionHasher_HeaderFile