GField Class Reference

Abstract base class representing a magnetic field. More...

#include <gfield.h>

Public Member Functions
	GField (const std::shared_ptr< GOptions > &gopt)
	Construct the field base with the provided options (for logging and configuration access).
virtual void	GetFieldValue (const double x[3], double *bfield) const =0
	Compute the magnetic field vector at a given position.
G4FieldManager *	create_FieldManager ()
	Create a G4FieldManager configured for this field.
virtual void	load_field_definitions (GFieldDefinition gfd)
	Store the field definition used to configure this field instance.
int	get_field_parameter_int (const std::string &key)
	Convenience accessor for integer-valued parameters stored in field_parameters.
double	get_field_parameter_double (const std::string &key)
	Convenience accessor for floating-point parameters stored in field_parameters.
void	set_loggers (const std::shared_ptr< GOptions > &g)
	Hook for configuring module loggers from options.
Public Member Functions inherited from GBase< GField >
	GBase (const std::shared_ptr< GOptions > &gopt, std::string logger_name="")
	GBase (const std::shared_ptr< GLogger > &logger)
	GBase (const GBase &)=default
	GBase (GBase &&) noexcept=default
virtual	~GBase ()
GBase &	operator= (const GBase &)=default
GBase &	operator= (GBase &&) noexcept=default

Static Public Member Functions
static GField *	instantiate (const dlhandle h, const std::shared_ptr< GOptions > g)
	Instantiate a field object from a plugin handle.

Protected Attributes
GFieldDefinition	gfield_definitions
	Stored field definition used for configuration and logging.
Protected Attributes inherited from GBase< GField >
std::shared_ptr< GLogger >	log

Detailed Description

A concrete field implementation must provide GetFieldValue() and may override load_field_definitions() to parse/cache configuration from a GFieldDefinition.

Integration:

• The field is also a G4MagneticField and is used by Geant4 stepping infrastructure.
• The helper create_FieldManager() constructs a G4FieldManager and its chord finder using a supported stepper name.

Definition at line 99 of file gfield.h.

Constructor & Destructor Documentation

GField()

GField::GField ( const std::shared_ptr< GOptions > & gopt )

inlineexplicit

Parameters

gopt	Shared options object.

Definition at line 106 of file gfield.h.

Member Function Documentation

create_FieldManager()

G4FieldManager * GField::create_FieldManager

(

)

Returns

Newly allocated G4FieldManager pointer.

The manager is created using:

• G4Mag_UsualEqRhs as the equation of motion,
• one of the supported integration steppers (selected by name),
• a G4ChordFinder constructed with the configured minimum step.

Ownership:

• The returned object is heap-allocated. In this module it is owned by GMagneto.

Definition at line 24 of file gfield.cc.

get_field_parameter_double()

double GField::get_field_parameter_double ( const std::string & key )

inline

Parameters

key	Map key to retrieve.

Returns

Parsed floating-point value.

Definition at line 151 of file gfield.h.

get_field_parameter_int()

int GField::get_field_parameter_int ( const std::string & key )

inline

Parameters

key	Map key to retrieve.

Returns

Parsed integer value.

Definition at line 144 of file gfield.h.

GetFieldValue()

virtual void GField::GetFieldValue ( const double x[3], double * bfield ) const

pure virtual

Parameters

x	Position in the lab frame as {x,y,z}.
bfield	Output array filled with {Bx,By,Bz}.

This method is the key interface used by Geant4 when transporting tracks in a field.

instantiate()

static GField * GField::instantiate ( const dlhandle h, const std::shared_ptr< GOptions > g )

inlinestatic

Parameters

h	Dynamic library handle.
g	Shared options passed to the plugin factory.

Returns

Newly allocated field pointer, or nullptr on failure.

The plugin must export a C symbol named "GFieldFactory" with a compatible signature. This method looks up that symbol and calls it to construct the concrete GField instance.

Definition at line 197 of file gfield.h.

load_field_definitions()

virtual void GField::load_field_definitions ( GFieldDefinition gfd )

inlinevirtual

Parameters

gfd	Field definition to copy into internal storage.

Concrete implementations typically override this method to parse and cache frequently used parameters.

Reimplemented in GField_MultipolesFactory.

Definition at line 137 of file gfield.h.

set_loggers()

void GField::set_loggers ( const std::shared_ptr< GOptions > & g )

inline

Parameters

g	Shared options object.

This module currently does not add additional logger wiring here.

Definition at line 159 of file gfield.h.

Field Documentation

gfield_definitions

GFieldDefinition GField::gfield_definitions

protected

Definition at line 185 of file gfield.h.

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The documentation for this class was generated from the following files:

• gfield.h
• gfield.cc