BFieldManager.h

/**************************************************************************
 * basf2 (Belle II Analysis Software Framework)                           *
 * Author: The Belle II Collaboration                                     *
 *                                                                        *
 * See git log for contributors and copyright holders.                    *
 * This file is licensed under LGPL-3.0, see LICENSE.md.                  *
 **************************************************************************/
 
#pragma once
 
#include <vector>
#include <framework/logging/Logger.h>
#include <framework/geometry/B2Vector3.h>
#include <framework/gearbox/Unit.h>
#include <framework/database/DBObjPtr.h>
#include <framework/dbobjects/MagneticField.h>
 
namespace Belle2 {
  class BFieldManager {
  public:
    static void getField(const double* pos, double* field);
    static TVector3 getField(const TVector3& pos)
    {
      return getField(B2Vector3D(pos)).GetTVector3();
    }
 
    static B2Vector3D getField(double x, double y, double z)
    {
      return getField(B2Vector3D(x, y, z));
    }
    static B2Vector3D getField(const B2Vector3D& pos)
    {
      return BFieldManager::getInstance().calculate(pos);
    }
    static B2Vector3D getFieldInTesla(const B2Vector3D& pos)
    {
      return getField(pos) / Unit::T;
    }
    static BFieldManager& getInstance();
  private:
    BFieldManager() = default;
    BFieldManager(BFieldManager&) = delete;
    BFieldManager& operator=(const BFieldManager&) = delete;
    ~BFieldManager() = default;
    B2Vector3D calculate(const B2Vector3D& pos) const;
    DBObjPtr<MagneticField> m_magfield;
  };
 
  inline B2Vector3D BFieldManager::calculate(const B2Vector3D& pos) const
  {
    if (!m_magfield) B2FATAL("Could not load magnetic field configuration from database");
    return m_magfield->getField(pos);
  };
 
  inline void BFieldManager::getField(const double* pos, double* field)
  {
    B2Vector3D fieldvec = getField(B2Vector3D(pos));
    fieldvec.GetXYZ(field);
  }
}