da/de1/BFieldCache_8h_source.html

/*

  Copyright (C) 2002-2024 CERN for the benefit of the ATLAS collaboration

*/


#ifndef BFIELDCACHE_H

#define BFIELDCACHE_H


#include "CxxUtils/restrict.h"

#include "CxxUtils/vec.h"

#include "MagFieldElements/BFieldVector.h"


class BFieldCache

{

public:

  // default constructor sets unphysical boundaries, so that inside() will fail

  BFieldCache() = default;

  // make this cache invalid, so that inside() will fail

  void invalidate();


  // set the z, r, phi range that defines the bin

  void setRange(double zmin,

                double zmax,

                double rmin,

                double rmax,

                double phimin,

                double phimax);


  // set the 3x8 field array.

  void setField(const CxxUtils::vec<double, 8>& field1,

                const CxxUtils::vec<double, 8>& field2,

                const CxxUtils::vec<double, 8>& field3);


  // set the multiplicative factor for the field vectors

  void setBscale(double bscale);

  float bscale() const;


  // test if (z, r, phi) is inside this bin

  bool inside(double z, double r, double phi) const;

  // interpolate the field and return B[3].

  // also compute field derivatives if deriv[9] is given.

  void getB(const double* ATH_RESTRICT xyz,

            double r,

            double phi,

            double* ATH_RESTRICT B,

            double* ATH_RESTRICT deriv = nullptr) const;


private:

  // bin range in z

  double m_zmin = 0.0;

  double m_zmax = 0.0;

  // bin range in r

  double m_rmin = 0.0;

  double m_rmax = 0.0;

  // bin range in phi

  double m_phimin = 0.0;

  double m_phimax = -1.0;

  // 1/(bin size) in z, r, phi

  double m_invz;

  double m_invr;

  double m_invphi;

  double m_scale;                   // unit of m_field in kT

  alignas(16) double m_field[3][8]; // (Bz,Br,Bphi) at 8 corners of the bin

};


#include "MagFieldElements/BFieldCache.icc"

#endif