MagneticField.h

/**************************************************************************
 * BASF2 (Belle Analysis Framework 2)                                     *
 * Copyright(C) 2017 - Belle II Collaboration                             *
 *                                                                        *
 * Author: The Belle II Collaboration                                     *
 * Contributors: Martin Ritter                                            *
 *                                                                        *
 * This software is provided "as is" without any warranty.                *
 **************************************************************************/
 
#pragma once
#include <framework/geometry/B2Vector3.h>
#include <framework/dbobjects/MagneticFieldComponent.h>
#include <framework/gearbox/Unit.h>
 
namespace Belle2 {
  class MagneticField: public TObject {
  public:
    MagneticField(): TObject() {}
    ~MagneticField()
    {
      for (auto c : m_components) delete c;
      m_components.clear();
    }
    MagneticField(const MagneticField&) = delete;
    MagneticField(MagneticField&& other) noexcept: m_components(std::move(other.m_components)) {}
    B2Vector3D getField(const B2Vector3D& pos) const;
    B2Vector3D getFieldInTesla(const B2Vector3D& pos) const { return getField(pos) / Unit::T; }
    void addComponent(MagneticFieldComponent* component) { m_components.emplace_back(component); }
  private:
    std::vector<MagneticFieldComponent*> m_components;
    ClassDef(MagneticField, 1);
  };
 
  inline B2Vector3D MagneticField::getField(const B2Vector3D& pos) const
  {
    B2Vector3D field;
    for (auto c : m_components) {
      if (c->inside(pos)) {
        // is it an exclusive component? If so return the field
        if (c->isExclusive()) return c->getField(pos);
        // else add it to what we already have
        field += c->getField(pos);
      }
    }
    return field;
  }
} //Belle2 namespace