#include <StraightLineIntersector.h>

Inheritance diagram for Trk::StraightLineIntersector:

Collaboration diagram for Trk::StraightLineIntersector:

Public Member Functions
	StraightLineIntersector (const std::string &type, const std::string &name, const IInterface *parent)

virtual StatusCode	finalize () override

virtual std::optional< TrackSurfaceIntersection >	intersectSurface (const Surface &surface, const TrackSurfaceIntersection &trackTrackSurfaceIntersection, const double qOverP) const override
	IIntersector interface method for general Surface type. More...

virtual std::optional< TrackSurfaceIntersection >	approachPerigeeSurface (const PerigeeSurface &surface, const TrackSurfaceIntersection &trackTrackSurfaceIntersection, const double) const override
	IIntersector interface method for specific Surface type : PerigeeSurface. More...

virtual std::optional< TrackSurfaceIntersection >	approachStraightLineSurface (const StraightLineSurface &surface, const TrackSurfaceIntersection &trackTrackSurfaceIntersection, const double) const override
	IIntersector interface method for specific Surface type : StraightLineSurface. More...

virtual std::optional< TrackSurfaceIntersection >	intersectCylinderSurface (const CylinderSurface &surface, const TrackSurfaceIntersection &trackTrackSurfaceIntersection, const double) const override
	IIntersector interface method for specific Surface type : CylinderSurface. More...

virtual std::optional< TrackSurfaceIntersection >	intersectDiscSurface (const DiscSurface &surface, const TrackSurfaceIntersection &trackTrackSurfaceIntersection, const double) const override
	IIntersector interface method for specific Surface type : DiscSurface. More...

virtual std::optional< TrackSurfaceIntersection >	intersectPlaneSurface (const PlaneSurface &surface, const TrackSurfaceIntersection &trackTrackSurfaceIntersection, const double) const override
	IIntersector interface method for specific Surface type : PlaneSurface. More...

virtual bool	isValid (Amg::Vector3D, Amg::Vector3D) const override
	IIntersector interface method for validity check over a particular extrapolation range. More...

Private Member Functions
double	distanceToCylinder (const TrackSurfaceIntersection &isect, const double cylinderRadius) const

double	distanceToDisc (const TrackSurfaceIntersection &isect, const double discZ) const

double	distanceToLine (const TrackSurfaceIntersection &isect, const Amg::Vector3D &linePosition, const Amg::Vector3D &lineDirection) const

double	distanceToPlane (const TrackSurfaceIntersection &isect, const Amg::Vector3D &planePosition, const Amg::Vector3D &planeNormal) const

void	step (TrackSurfaceIntersection &isect, double stepLength) const

Private Attributes
std::atomic< unsigned long long >	m_countExtrapolations

Detailed Description

Definition at line 22 of file StraightLineIntersector.h.

Constructor & Destructor Documentation

◆ StraightLineIntersector()

Trk::StraightLineIntersector::StraightLineIntersector	(	const std::string &	type,
		const std::string &	name,
		const IInterface *	parent
	)

Definition at line 26 of file StraightLineIntersector.cxx.

     :   base_class      (type, name, parent),
     m_countExtrapolations   (0)
 {
 }

Member Function Documentation

◆ approachPerigeeSurface()

std::optional< Trk::TrackSurfaceIntersection > Trk::StraightLineIntersector::approachPerigeeSurface	(	const PerigeeSurface &	surface,
		const TrackSurfaceIntersection &	trackTrackSurfaceIntersection,
		const double
	)		const

overridevirtual

IIntersector interface method for specific Surface type : PerigeeSurface.

Definition at line 78 of file StraightLineIntersector.cxx.

 {
   TrackSurfaceIntersection isect = trackIntersection;
   ++m_countExtrapolations;
  
   // straight line distance along track to closest approach to line
   const Amg::Vector3D&  lineDirection = surface.transform().rotation().col(2);
   double stepLength = distanceToLine (isect, surface.center(),lineDirection);
   step(isect, stepLength);
     
   return isect;
 }

◆ approachStraightLineSurface()

std::optional< Trk::TrackSurfaceIntersection > Trk::StraightLineIntersector::approachStraightLineSurface	(	const StraightLineSurface &	surface,
		const TrackSurfaceIntersection &	trackTrackSurfaceIntersection,
		const double
	)		const

overridevirtual

IIntersector interface method for specific Surface type : StraightLineSurface.

Definition at line 95 of file StraightLineIntersector.cxx.

 {
   TrackSurfaceIntersection isect = trackIntersection;
   ++m_countExtrapolations;
  
   // straight line distance along track to closest approach to line
   const Amg::Vector3D&  lineDirection = surface.transform().rotation().col(2);
   double stepLength = distanceToLine (isect, surface.center(),lineDirection);
   step(isect, stepLength);
  
   return isect;
 }

◆ distanceToCylinder()

double Trk::StraightLineIntersector::distanceToCylinder	(	const TrackSurfaceIntersection &	isect,
		const double	cylinderRadius
	)		const

inlineprivate

Definition at line 95 of file StraightLineIntersector.h.

                                                                               {
   const Amg::Vector3D& pos = isect.position();
   const Amg::Vector3D& dir = isect.direction();
   double sinThsqinv = 1. / dir.perp2();
   double stepLength = (-pos.x() * dir.x() - pos.y() * dir.y()) * sinThsqinv;
   double deltaRSq =
       (cylinderRadius * cylinderRadius - pos.perp2()) * sinThsqinv +
       stepLength * stepLength;
   if (deltaRSq > 0.)
     stepLength += sqrt(deltaRSq);
   return stepLength;
 }

◆ distanceToDisc()

double Trk::StraightLineIntersector::distanceToDisc	(	const TrackSurfaceIntersection &	isect,
		const double	discZ
	)		const

inlineprivate

Definition at line 109 of file StraightLineIntersector.h.

                                                                      {
   const Amg::Vector3D& pos = isect.position();
   const Amg::Vector3D& dir = isect.direction();
   return (discZ - pos.z()) / dir.z();
 }

◆ distanceToLine()

double Trk::StraightLineIntersector::distanceToLine	(	const TrackSurfaceIntersection &	isect,
		const Amg::Vector3D &	linePosition,
		const Amg::Vector3D &	lineDirection
	)		const

inlineprivate

Definition at line 116 of file StraightLineIntersector.h.

                                             {
   // offset joining track to line is given by
   //   offset = linePosition + a*lineDirection - trackPosition -
   //   b*trackDirection
   //
   // offset is perpendicular to both line and track at solution i.e.
   //   lineDirection.dot(offset) = 0
   //   trackDirection.dot(offset) = 0
   const Amg::Vector3D& pos = isect.position();
   const Amg::Vector3D& dir = isect.direction();
   double cosAngle = lineDirection.dot(dir);
   return (linePosition - pos).dot(dir - lineDirection * cosAngle) /
          (1. - cosAngle * cosAngle);
 }

◆ distanceToPlane()

double Trk::StraightLineIntersector::distanceToPlane	(	const TrackSurfaceIntersection &	isect,
		const Amg::Vector3D &	planePosition,
		const Amg::Vector3D &	planeNormal
	)		const

inlineprivate

Definition at line 133 of file StraightLineIntersector.h.

                                           {
   // take the normal component of the offset from track position to plane
   // position this is equal to the normal component of the required distance
   // along the track direction
   const Amg::Vector3D& pos = isect.position();
   const Amg::Vector3D& dir = isect.direction();
   return planeNormal.dot(planePosition - pos) / planeNormal.dot(dir);
 }

◆ finalize()

StatusCode Trk::StraightLineIntersector::finalize ( )

overridevirtual

Definition at line 35 of file StraightLineIntersector.cxx.

 {
     ATH_MSG_DEBUG( "finalized after " << m_countExtrapolations << " extrapolations" );
     return StatusCode::SUCCESS;
 }

◆ intersectCylinderSurface()

std::optional< Trk::TrackSurfaceIntersection > Trk::StraightLineIntersector::intersectCylinderSurface	(	const CylinderSurface &	surface,
		const TrackSurfaceIntersection &	trackTrackSurfaceIntersection,
		const double
	)		const

overridevirtual

IIntersector interface method for specific Surface type : CylinderSurface.

Definition at line 112 of file StraightLineIntersector.cxx.

 {
   TrackSurfaceIntersection isect = trackIntersection;
   ++m_countExtrapolations;
   
   // calculate straight line distance along track to intersect with cylinder radius
   double cylinderRadius = surface.globalReferencePoint().perp();
   double stepLength = distanceToCylinder(isect, cylinderRadius);
   step(isect, stepLength);
  
   return isect;
 }

◆ intersectDiscSurface()

std::optional< Trk::TrackSurfaceIntersection > Trk::StraightLineIntersector::intersectDiscSurface	(	const DiscSurface &	surface,
		const TrackSurfaceIntersection &	trackTrackSurfaceIntersection,
		const double
	)		const

overridevirtual

IIntersector interface method for specific Surface type : DiscSurface.

Definition at line 129 of file StraightLineIntersector.cxx.

 {
   TrackSurfaceIntersection isect = trackIntersection;
   ++m_countExtrapolations;
  
   // straight line distance along track to intersect with disc
   double stepLength = distanceToDisc(isect, surface.center().z());
   step(isect, stepLength);
   
   return isect;
 }

◆ intersectPlaneSurface()

std::optional< Trk::TrackSurfaceIntersection > Trk::StraightLineIntersector::intersectPlaneSurface	(	const PlaneSurface &	surface,
		const TrackSurfaceIntersection &	trackTrackSurfaceIntersection,
		const double
	)		const

overridevirtual

IIntersector interface method for specific Surface type : PlaneSurface.

Definition at line 145 of file StraightLineIntersector.cxx.

 {
   TrackSurfaceIntersection isect = trackIntersection;
   ++m_countExtrapolations;
  
   // straight line distance along track to intersect with plane
   double stepLength = distanceToPlane (isect, surface.center(),surface.normal());
   step(isect, stepLength);
   stepLength = distanceToPlane (isect, surface.center(),surface.normal());
  
   return isect;
 }

◆ intersectSurface()

std::optional< Trk::TrackSurfaceIntersection > Trk::StraightLineIntersector::intersectSurface	(	const Surface &	surface,
		const TrackSurfaceIntersection &	trackTrackSurfaceIntersection,
		const double	qOverP
	)		const

overridevirtual

IIntersector interface method for general Surface type.

Definition at line 43 of file StraightLineIntersector.cxx.

 {
  
     const auto surfaceType = surface.type();
     if (surfaceType == Trk::SurfaceType::Plane) {
       return intersectPlaneSurface(static_cast<const PlaneSurface&>(surface),
                                    trackIntersection, qOverP);
     }
     if (surfaceType == Trk::SurfaceType::Line) {
       return approachStraightLineSurface(
           static_cast<const StraightLineSurface&>(surface), trackIntersection,
           qOverP);
     }
     if (surfaceType == Trk::SurfaceType::Cylinder) {
       return intersectCylinderSurface(
           static_cast<const CylinderSurface&>(surface), trackIntersection,
           qOverP);
     }
     if (surfaceType == Trk::SurfaceType::Disc) {
       return intersectDiscSurface(static_cast<const DiscSurface&>(surface),
                                   trackIntersection, qOverP);
     }
     if (surfaceType == Trk::SurfaceType::Perigee) {
       return approachPerigeeSurface(static_cast<const PerigeeSurface&>(surface),
                                     trackIntersection, qOverP);
     }
  
     ATH_MSG_WARNING( " unrecognized Surface" );
     return std::nullopt;
 }

◆ isValid()

virtual bool Trk::StraightLineIntersector::isValid	(	Amg::Vector3D	,
		Amg::Vector3D
	)		const

inlineoverridevirtual

IIntersector interface method for validity check over a particular extrapolation range.

Definition at line 70 of file StraightLineIntersector.h.

                                                      {
     return true;
   }

◆ step()

void Trk::StraightLineIntersector::step	(	TrackSurfaceIntersection &	isect,
		double	stepLength
	)		const

inlineprivate

Definition at line 144 of file StraightLineIntersector.h.

                                                                    {
   isect.position() += stepLength * isect.direction();
   isect.pathlength() += stepLength;
 }

Member Data Documentation

◆ m_countExtrapolations

std::atomic<unsigned long long> Trk::StraightLineIntersector::m_countExtrapolations

mutableprivate

Definition at line 90 of file StraightLineIntersector.h.

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

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ StraightLineIntersector()

Member Function Documentation

◆ approachPerigeeSurface()

◆ approachStraightLineSurface()

◆ distanceToCylinder()

◆ distanceToDisc()

◆ distanceToLine()

◆ distanceToPlane()

◆ finalize()

◆ intersectCylinderSurface()

◆ intersectDiscSurface()

◆ intersectPlaneSurface()

◆ intersectSurface()

◆ isValid()

◆ step()

Member Data Documentation

◆ m_countExtrapolations