Gabriele Cosmo
103 lines
4.3 KiB
C++
103 lines
4.3 KiB
C++
//
|
|
// ********************************************************************
|
|
// * DISCLAIMER *
|
|
// * *
|
|
// * The following disclaimer summarizes all the specific disclaimers *
|
|
// * of contributors to this software. The specific disclaimers,which *
|
|
// * govern, are listed with their locations in: *
|
|
// * http://cern.ch/geant4/license *
|
|
// * *
|
|
// * Neither the authors of this software system, nor their employing *
|
|
// * institutes,nor the agencies providing financial support for this *
|
|
// * work make any representation or warranty, express or implied, *
|
|
// * regarding this software system or assume any liability for its *
|
|
// * use. *
|
|
// * *
|
|
// * This code implementation is the intellectual property of the *
|
|
// * GEANT4 collaboration. *
|
|
// * By copying, distributing or modifying the Program (or any work *
|
|
// * based on the Program) you indicate your acceptance of this *
|
|
// * statement, and all its terms. *
|
|
// ********************************************************************
|
|
//
|
|
//
|
|
// $Id: G4Field.hh,v 1.9 2004/09/01 09:59:06 japost Exp $
|
|
// GEANT4 tag $Name: geant4-07-00-cand-03 $
|
|
//
|
|
//
|
|
// class G4Field
|
|
//
|
|
// Class description:
|
|
//
|
|
// Abstract class for any kind of Field.
|
|
// It allows any kind of field (vector, scalar, tensor and any set of them)
|
|
// to be defined by implementing the inquiry function interface.
|
|
//
|
|
// The key method is GetFieldValue( const double Point[4],
|
|
// ************* double *fieldArr )
|
|
// Given an input position/time vector 'Point',
|
|
// this method must return the value of the field in "fieldArr".
|
|
//
|
|
// A field must also specify whether it changes a track's energy:
|
|
// DoesFieldChangeEnergy()
|
|
// *********************
|
|
// A field must co-work with a corresponding Equation of Motion, to
|
|
// enable the integration of a particle's position, momentum and, optionally,
|
|
// spin. For this a field and its equation of motion must follow the
|
|
// same convention for the order of field components in the array "fieldArr"
|
|
// -------------------------------------------------------------------
|
|
// History:
|
|
// - Created: John Apostolakis, 10.03.1997
|
|
// - Modified:
|
|
// V. Grichine 8 Nov 2001: Extended "Point" arg to [4] array to add time
|
|
// J. Apostolakis 5 Nov 2003: Added virtual method DoesFieldChangeEnergy()
|
|
// J. Apostolakis 31 Aug 2004: Information on convention for components
|
|
// -------------------------------------------------------------------
|
|
|
|
#ifndef G4FIELD_HH
|
|
#define G4FIELD_HH
|
|
|
|
#include "G4Types.hh"
|
|
|
|
class G4Field
|
|
{
|
|
public: // with description
|
|
|
|
virtual void GetFieldValue( const double Point[4],
|
|
double *fieldArr ) const = 0;
|
|
// Given the position time vector 'Point',
|
|
// return the value of the field in the array fieldArr.
|
|
// Notes:
|
|
// 1) The 'Point' vector has the following structure:
|
|
// Point[0] is x ( position, in Geant4 units )
|
|
// Point[1] is y
|
|
// Point[2] is z
|
|
// Point[3] is t ( time, in Geant4 units )
|
|
// 2) The convention for the components of the field
|
|
// array 'fieldArr' are determined by the type of field.
|
|
// See for example the class G4ElectroMagneticField.
|
|
|
|
G4Field(){;}
|
|
virtual ~G4Field(){;}
|
|
inline G4Field& operator = (const G4Field &p);
|
|
|
|
// A field signature function that can be used to insure
|
|
// that the Equation of motion object and the G4Field object
|
|
// have the same "field signature"?
|
|
|
|
virtual G4bool DoesFieldChangeEnergy() const= 0 ;
|
|
// Each type/class of field should respond this accordingly
|
|
// For example:
|
|
// - an electric field should return "true"
|
|
// - a pure magnetic field should return "false"
|
|
|
|
};
|
|
|
|
inline G4Field& G4Field::operator = (const G4Field &p)
|
|
{
|
|
if (&p != this) { *this = p; }
|
|
return *this;
|
|
}
|
|
|
|
#endif /* G4FIELD_HH */
|