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.
//
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// commercial license or contractual agreement.

#ifndef _GeomHash_AxisPlacement_HeaderFile
#define _GeomHash_AxisPlacement_HeaderFile

#include <Standard_HashUtils.hxx>
#include <gp_Ax2.hxx>
#include <GeomHash_PointHasher.pxx>
#include <GeomHash_DirectionHasher.pxx>
#include <Precision.hxx>

//! OCCT-style hasher for gp_Ax2 (axis placement).
//! Used for geometry deduplication.
//! Compositional hasher using PointHasher and DirectionHasher.
struct GeomHash_AxisPlacement
{
  double CompTolerance;
  double HashTolerance;

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

  // Hashes the axis placement by location, axis direction, and X direction.
  std::size_t operator()(const gp_Ax2& theAxisPlacement) const noexcept
  {
    const GeomHash_PointHasher     aPointHasher(CompTolerance, HashTolerance);
    const GeomHash_DirectionHasher aDirectionHasher(CompTolerance, HashTolerance);

    const std::size_t aHashes[3] = {aPointHasher(theAxisPlacement.Location()),
                                    aDirectionHasher(theAxisPlacement.Direction()),
                                    aDirectionHasher(theAxisPlacement.XDirection())};

    return opencascade::hashBytes(aHashes, sizeof(aHashes));
  }

  // Compares two axis placements.
  bool operator()(const gp_Ax2& theAxisPlacement1, const gp_Ax2& theAxisPlacement2) const noexcept
  {
    const GeomHash_PointHasher     aPointHasher(CompTolerance, HashTolerance);
    const GeomHash_DirectionHasher aDirectionHasher(CompTolerance, HashTolerance);

    return aPointHasher(theAxisPlacement1.Location(), theAxisPlacement2.Location())
           && aDirectionHasher(theAxisPlacement1.Direction(), theAxisPlacement2.Direction())
           && aDirectionHasher(theAxisPlacement1.XDirection(), theAxisPlacement2.XDirection());
  }
};

#endif // _GeomHash_AxisPlacement_HeaderFile