tracking::reco::TrackingGeometryUser Class Reference

a helper base class providing some methods to shorten access to common conditions used within the tracking reconstruction More...

#include <TrackingGeometryUser.h>

Public Member Functions
	TrackingGeometryUser (const std::string &name, framework::Process &p)
Public Member Functions inherited from framework::Producer
	Producer (const std::string &name, Process &process)
	Class constructor.
virtual void	process (Event &event) final
	Processing an event for a Producer is calling produce.
virtual void	produce (Event &event)=0
	Process the event and put new data products into it.
Public Member Functions inherited from framework::EventProcessor
	DECLARE_FACTORY (EventProcessor, EventProcessor *, const std::string &, Process &)
	declare that we have a factory for this class
	EventProcessor (const std::string &name, Process &process)
	Class constructor.
virtual	~EventProcessor ()=default
	Class destructor.
virtual void	configure (framework::config::Parameters &parameters)
	Callback for the EventProcessor to configure itself from the given set of parameters.
virtual void	beforeNewRun (ldmx::RunHeader &run_header)
	Callback for Producers to add parameters to the run header before conditions are initialized.
virtual void	onNewRun (const ldmx::RunHeader &run_header)
	Callback for the EventProcessor to take any necessary action when the run being processed changes.
virtual void	onFileOpen (EventFile &event_file)
	Callback for the EventProcessor to take any necessary action when a new event input ROOT file is opened.
virtual void	onFileClose (EventFile &event_file)
	Callback for the EventProcessor to take any necessary action when a event input ROOT file is closed.
virtual void	onProcessStart ()
	Callback for the EventProcessor to take any necessary action when the processing of events starts, such as creating histograms.
virtual void	onProcessEnd ()
	Callback for the EventProcessor to take any necessary action when the processing of events finishes, such as calculating job-summary quantities.
template<class T >
const T &	getCondition (const std::string &condition_name)
	Access a conditions object for the current event.
TDirectory *	getHistoDirectory ()
	Access/create a directory in the histogram file for this event processor to create histograms and analysis tuples.
void	setStorageHint (framework::StorageControl::Hint hint)
	Mark the current event as having the given storage control hint from this module_.
void	setStorageHint (framework::StorageControl::Hint hint, const std::string &purposeString)
	Mark the current event as having the given storage control hint from this module and the given purpose string.
int	getLogFrequency () const
	Get the current logging frequency from the process.
int	getRunNumber () const
	Get the run number from the process.
std::string	getName () const
	Get the processor name.
void	createHistograms (const std::vector< framework::config::Parameters > &histos)
	Internal function which is used to create histograms passed from the python configuration @parma histos vector of Parameters that configure histograms to create.

Protected Member Functions
const Acts::GeometryContext &	geometryContext ()
const Acts::MagneticFieldContext &	magneticFieldContext ()
const Acts::CalibrationContext &	calibrationContext ()
const geo::TrackersTrackingGeometry &	geometry ()
void	loadBField (const std::string &path, const BFieldDistortion &distortion={})
	Load the interpolated B-field map from path and cache it.
void	loadBField (const BFieldDistortion &distortion={})
	Load B-field from the path recorded in the detector GDML.
std::shared_ptr< Acts::MagneticFieldProvider >	bField () const
	Return the loaded B-field provider.
Protected Member Functions inherited from framework::EventProcessor
void	abortEvent ()
	Abort the event immediately.

Static Protected Member Functions
static BFieldDistortion	bFieldDistortion (const framework::config::Parameters &parameters)
	Build a BFieldDistortion from processor configuration.

Private Member Functions
template<typename ConditionType >
const ConditionType &	getNamedCondition ()
	Templated condition access code for our conditions with static names.

Private Attributes
std::shared_ptr< Acts::MagneticFieldProvider >	b_field_ {nullptr}

Additional Inherited Members
Protected Attributes inherited from framework::EventProcessor
HistogramPool	histograms_
	helper object for making and filling histograms
NtupleManager &	ntuple_ {NtupleManager::getInstance()}
	Manager for any ntuples.
logging::logger	the_log_
	The logger for this EventProcessor.

Detailed Description

a helper base class providing some methods to shorten access to common conditions used within the tracking reconstruction

Definition at line 22 of file TrackingGeometryUser.h.

Constructor & Destructor Documentation

TrackingGeometryUser()

tracking::reco::TrackingGeometryUser::TrackingGeometryUser	(	const std::string &	name,
		framework::Process &	p )

Definition at line 7 of file TrackingGeometryUser.cxx.

    : framework::Producer(name, p) {}

Member Function Documentation

bField()

std::shared_ptr< Acts::MagneticFieldProvider > tracking::reco::TrackingGeometryUser::bField ( ) const

inlineprotected

Return the loaded B-field provider.

Null until loadBField() is called.

Definition at line 67 of file TrackingGeometryUser.h.

                                                          {
    return b_field_;
  }

Referenced by tracking::reco::CKFProcessor::onNewRun(), and tracking::reco::GSFProcessor::onNewRun().

bFieldDistortion()

BFieldDistortion tracking::reco::TrackingGeometryUser::bFieldDistortion ( const framework::config::Parameters & parameters )

staticprotected

Build a BFieldDistortion from processor configuration.

Config is in the LDMX global frame (x bend, y vertical, z beam); this permutes it into the ACTS frame the lookup works in. Parameters:

• bfield_translation {dx, dy, dz} [mm], default {0, 0, 0}
• bfield_rotation {ax, ay, az} [rad], default {0, 0, 0}
• bfield_pivot {x, y, z} [mm], default {0, 0, -400}, the map origin
• bfield_scale field scaling, default 1

A positive translation moves the magnet, so the field at a fixed point becomes the nominal field from further upstream.

Definition at line 71 of file TrackingGeometryUser.cxx.

                                                 {
  const auto translation{
      parameters.get<std::vector<double>>("bfield_translation", {0., 0., 0.})};
  const auto rotation{
      parameters.get<std::vector<double>>("bfield_rotation", {0., 0., 0.})};
  const auto pivot{parameters.get<std::vector<double>>(
      "bfield_pivot", {0., 0., -DIPOLE_OFFSET})};
 
  auto require_three = [](const std::string& name,
                          const std::vector<double>& v) {
    if (v.size() != 3)
      EXCEPTION_RAISE("BadConf", name + " must have three entries");
  };
  require_three("bfield_translation", translation);
  require_three("bfield_rotation", rotation);
  require_three("bfield_pivot", pivot);
 
  // LDMX (x, y, z) -> ACTS (z, x, y); a cyclic permutation, so the rotation
  // angles reorder the same way as the positions
  BFieldDistortion distortion;
  distortion.translation_ =
      Acts::Vector3(translation[2], translation[0], translation[1]);
  distortion.rotation_ = Acts::Vector3(rotation[2], rotation[0], rotation[1]);
  distortion.pivot_ = Acts::Vector3(pivot[2], pivot[0], pivot[1]);
  distortion.scale_ = parameters.get<double>("bfield_scale", 1.);
  return distortion;
}

References framework::config::Parameters::get(), BFieldDistortion::pivot_, BFieldDistortion::rotation_, BFieldDistortion::scale_, and BFieldDistortion::translation_.

Referenced by tracking::reco::CKFProcessor::configure(), and tracking::reco::GSFProcessor::configure().

calibrationContext()

const Acts::CalibrationContext & tracking::reco::TrackingGeometryUser::calibrationContext ( )

protected

Definition at line 17 of file TrackingGeometryUser.cxx.

                                                                       {
  return getNamedCondition<geo::CalibrationContext>().get();
}

geometry()

const geo::TrackersTrackingGeometry & tracking::reco::TrackingGeometryUser::geometry ( )

protected

Definition at line 20 of file TrackingGeometryUser.cxx.

                                                                  {
  return getNamedCondition<geo::TrackersTrackingGeometry>();
}

geometryContext()

const Acts::GeometryContext & tracking::reco::TrackingGeometryUser::geometryContext ( )

protected

Definition at line 11 of file TrackingGeometryUser.cxx.

                                                                 {
  return getNamedCondition<geo::GeometryContext>().get();
}

getNamedCondition()

template<typename ConditionType >

const ConditionType & tracking::reco::TrackingGeometryUser::getNamedCondition ( )

inlineprivate

Templated condition access code for our conditions with static names.

We assume that the condition has a constant name stored in ConditionType::NAME

Template Parameters

ConditionType

type of condition we are retrieving

Returns

condition object

Definition at line 84 of file TrackingGeometryUser.h.

                                           {
    return getCondition<ConditionType>(ConditionType::NAME);
  }

References framework::EventProcessor::getCondition().

loadBField() [1/2]

void tracking::reco::TrackingGeometryUser::loadBField ( const BFieldDistortion & distortion = {} )

protected

Load B-field from the path recorded in the detector GDML.

Definition at line 24 of file TrackingGeometryUser.cxx.

                                                                        {
  loadBField(geometry().fieldMapFile(), distortion);
}

loadBField() [2/2]

void tracking::reco::TrackingGeometryUser::loadBField ( const std::string & path, const BFieldDistortion & distortion = {} )

protected

Load the interpolated B-field map from path and cache it.

Uses the standard LDMX→ACTS coordinate transform plus DIPOLE_OFFSET. An optional distortion can be supplied to deliberately mis-place the reconstruction field for systematic studies; the default leaves the field bit-for-bit nominal.

Parameters

path	Path to the field map text file.
distortion	Optional mis-placement of the reconstruction field.

Definition at line 28 of file TrackingGeometryUser.cxx.

                                                                          {
  if (path.empty()) {
    ldmx_log(warn) << "No B-field map path provided — using zero B-field";
    b_field_ =
        std::make_shared<Acts::ConstantBField>(Acts::Vector3(0., 0., 0.));
    return;
  }
 
  if (distortion.isNominal()) {
    b_field_ = std::make_shared<InterpolatedMagneticField3>(
        loadDefaultBField(path, defaultTransformPos, defaultTransformBField));
    return;
  }
 
  const Acts::RotationMatrix3 rot{distortion.rotationMatrix()};
  const Acts::RotationMatrix3 rot_inv{rot.transpose()};
  const Acts::Vector3 translation{distortion.translation_};
  const Acts::Vector3 pivot{distortion.pivot_};
  const double scale{distortion.scale_};
 
  // undo the distortion, then the nominal ACTS -> map transform
  auto transform_pos = [rot_inv, translation, pivot](const Acts::Vector3& pos) {
    return defaultTransformPos(rot_inv * (pos - translation - pivot) + pivot);
  };
  // nominal map -> ACTS transform, then redo the distortion
  auto transform_b = [rot, scale](const Acts::Vector3& field,
                                  const Acts::Vector3& pos) {
    return Acts::Vector3(scale * (rot * defaultTransformBField(field, pos)));
  };
 
  ldmx_log(info) << "B-field distortion active (LDMX frame): translation ("
                 << translation(1) << ", " << translation(2) << ", "
                 << translation(0) << ") mm, rotation ("
                 << distortion.rotation_(1) << ", " << distortion.rotation_(2)
                 << ", " << distortion.rotation_(0) << ") rad about ("
                 << pivot(1) << ", " << pivot(2) << ", " << pivot(0)
                 << ") mm, scale " << scale;
 
  b_field_ = std::make_shared<InterpolatedMagneticField3>(
      loadDefaultBField(path, transform_pos, transform_b));
}

References BFieldDistortion::isNominal(), BFieldDistortion::pivot_, BFieldDistortion::rotation_, BFieldDistortion::rotationMatrix(), BFieldDistortion::scale_, and BFieldDistortion::translation_.

Referenced by tracking::reco::CKFProcessor::onNewRun(), and tracking::reco::GSFProcessor::onNewRun().

magneticFieldContext()

const Acts::MagneticFieldContext & tracking::reco::TrackingGeometryUser::magneticFieldContext ( )

protected

Definition at line 14 of file TrackingGeometryUser.cxx.

                                                                           {
  return getNamedCondition<geo::MagneticFieldContext>().get();
}

Member Data Documentation

b_field_

std::shared_ptr<Acts::MagneticFieldProvider> tracking::reco::TrackingGeometryUser::b_field_ {nullptr}

private

Definition at line 72 of file TrackingGeometryUser.h.

{nullptr};

---

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

• Tracking/include/Tracking/Reco/TrackingGeometryUser.h
• Tracking/src/Tracking/Reco/TrackingGeometryUser.cxx