#include <OffsetRadialStripTopology.h>

Inheritance diagram for OffsetRadialStripTopology:

Public Member Functions
virtual int	channel (int strip) const =0

virtual int	channel (const LocalPoint &lp) const =0

virtual LocalPoint	localPosition (float strip) const

virtual LocalPoint	localPosition (const MeasurementPoint &) const

virtual MeasurementPoint	measurementPosition (const LocalPoint &) const

	OffsetRadialStripTopology (int numberOfStrips, float stripPhiPitch, float detectorHeight, float radialDistance, float stripOffset, float yCentre)

virtual float	strip (const LocalPoint &) const

float	stripAngle (float strip) const

virtual float	stripOffset (void) const

virtual	~OffsetRadialStripTopology ()

Public Member Functions inherited from CSCRadialStripTopology
float	angularWidth () const

float	centreToIntersection () const

	CSCRadialStripTopology (int ns, float aw, float dh, float r, float yAx=1.f, float yMid=0.)

float	detHeight () const

virtual LocalError	localError (float strip, float stripErr2) const

virtual LocalError	localError (const MeasurementPoint &, const MeasurementError &) const

virtual float	localPitch (const LocalPoint &) const

virtual float	localStripLength (const LocalPoint &) const

virtual MeasurementError	measurementError (const LocalPoint &, const LocalError &) const

virtual int	nearestStrip (const LocalPoint &) const

virtual int	nstrips () const

float	originToIntersection () const

float	phiOfOneEdge () const

virtual float	phiPitch (void) const

virtual float	stripLength () const

float	xOfStrip (int strip, float y) const

float	yAxisOrientation () const

float	yCentreOfStripPlane () const

float	yDistanceToIntersection (float y) const

float	yExtentOfStripPlane () const

virtual	~CSCRadialStripTopology ()

Public Member Functions inherited from RadialStripTopology
virtual float	pitch () const final

virtual	~RadialStripTopology ()

Public Member Functions inherited from StripTopology
virtual float	coveredStrips (const LocalPoint &lp1, const LocalPoint &lp2) const

virtual LocalError	localError (float strip, float stripErr2, const Topology::LocalTrackPred &) const
	conversion taking also the angle from the predicted track state More...

virtual float	localPitch (const LocalPoint &lp, const Topology::LocalTrackAngles &) const
	conversion taking also the angle from the track state (LocalTrajectoryParameters) More...

virtual LocalPoint	localPosition (float strip, const Topology::LocalTrackPred &) const
	conversion taking also the predicted track state More...

virtual float	localStripLength (const LocalPoint &lp, const Topology::LocalTrackAngles &) const
	conversion taking also the angle from the track state (LocalTrajectoryParameters) More...

virtual float	strip (const LocalPoint &lp, const Topology::LocalTrackAngles &) const
	conversion taking also the angle from the track state (LocalTrajectoryParameters) More...

virtual	~StripTopology ()

Public Member Functions inherited from Topology
virtual int	channel (const LocalPoint &lp, const LocalTrackAngles &) const
	conversion taking also the angle from the track state More...

virtual LocalError	localError (const MeasurementPoint &mp, const MeasurementError &me, const LocalTrackPred &) const
	conversion taking also the angle from the predicted track state More...

virtual LocalPoint	localPosition (const MeasurementPoint &mp, const LocalTrackPred &) const
	conversion taking also the angle from the predicted track state More...

virtual MeasurementError	measurementError (const LocalPoint &lp, const LocalError &le, const LocalTrackAngles &) const
	conversion taking also the angle from the track state More...

virtual MeasurementPoint	measurementPosition (const LocalPoint &lp, const LocalTrackAngles &) const
	conversion taking also the angle from the track state More...

virtual	~Topology ()

Private Member Functions
LocalPoint	toLocal (float xprime, float yprime) const

LocalPoint	toPrime (const LocalPoint &) const

Private Attributes
float	theCosOff

float	theSinOff

float	theStripOffset

Friends
std::ostream &	operator<< (std::ostream &, const OffsetRadialStripTopology &)

Additional Inherited Members
Public Types inherited from Topology
typedef Point2DBase< double, LocalTag >	Local2DPoint

typedef Vector2D::MathVector	MathVector2D

typedef Basic2DVector< double >	Vector2D

Detailed Description

ABC defining RadialStripTopology with shifted offset so that it is not centred on local y (of parent chamber)

The offset is specified as a fraction of the strip angular width.

Author: Tim Cox

Definition at line 17 of file OffsetRadialStripTopology.h.

Constructor & Destructor Documentation

OffsetRadialStripTopology::OffsetRadialStripTopology	(	int	numberOfStrips,
		float	stripPhiPitch,
		float	detectorHeight,
		float	radialDistance,
		float	stripOffset,
		float	yCentre
	)

Constructor Note that yCentre is local y of symmetry centre of strip plane before the rotation shift: it is passed directly to RST base.

Definition at line 26 of file OffsetRadialStripTopology.cc.

References CSCRadialStripTopology::angularWidth(), funct::cos(), LogTrace, funct::sin(), theCosOff, and theSinOff.

                                      :
   CSCRadialStripTopology( numberOfStrips, stripPhiPitch, detectorHeight, radialDistance, +1, yCentre),
          theStripOffset( stripOffset )
 { 
   float rotate_by = stripOffset * angularWidth(); // now in angular units (radians, I hope)
   theCosOff = cos(rotate_by);
   theSinOff = sin(rotate_by);
 
   LogTrace("CSCStripTopology|CSC") << "fractional strip offset = " << stripOffset <<
     "\n angle = " << rotate_by << 
     " cos = " << theCosOff << " sin = " << theSinOff;
 }

virtual OffsetRadialStripTopology::~OffsetRadialStripTopology ( )

inlinevirtual

Definition at line 28 of file OffsetRadialStripTopology.h.

28 {};

Member Function Documentation

virtual int OffsetRadialStripTopology::channel ( int strip ) const

pure virtual

Channel number corresponding to a strip or a LocalPoint. Sometimes more than one strip is OR'ed into one channel.

Implemented in CSCUngangedStripTopology, and CSCGangedStripTopology.

virtual int OffsetRadialStripTopology::channel ( const LocalPoint & lp ) const

pure virtual

Channel number corresponding to a given LocalPoint.
This is effectively an integer version of strip(), with range 0 to nstrips-1.
LocalPoints outside the detector strip plane will be considered as contributing to the edge channels 0 or nstrips-1.

Reimplemented from CSCRadialStripTopology.

Implemented in CSCUngangedStripTopology, and CSCGangedStripTopology.

virtual LocalPoint OffsetRadialStripTopology::localPosition ( float strip ) const

inlinevirtual

LocalPoint for a given strip

Reimplemented from CSCRadialStripTopology.

Definition at line 37 of file OffsetRadialStripTopology.h.

References CSCRadialStripTopology::localPosition().

                                                       {
     // Pass through to base class since otherwise it is shadowed by the localPosition(const MP&).
     // Note that base class version is OK because it uses stripAngle() which is overridden in ORST!
     // Also note that xOfStrip from base class RST also works for ORST for the same reason.
     return CSCRadialStripTopology::localPosition( strip );
   }

LocalPoint OffsetRadialStripTopology::localPosition ( const MeasurementPoint & mp ) const

virtual

LocalPoint for a given MeasurementPoint

What's a MeasurementPoint?
A MeasurementPoint is a 2-dim object, with the 1st dim specifying the angular position in strip widths, and the 2nd dim specifying the fractional distance alone a strip.

Thus the 1st dimension measures the angular position wrt central line of symmetry of detector, in units of strip (angular) widths (range 0 to total angle subtended by a detector). The 2nd dimension measures the fractional position along the strip (range -0.5 to +0.5).

BEWARE! The components are not Cartesian.
BEWARE! Neither coordinate may correspond to either local x or local y.
BEWARE! This involves ONLY strip-related measurements, not CSC wires!

Reimplemented from CSCRadialStripTopology.

Definition at line 42 of file OffsetRadialStripTopology.cc.

References CSCRadialStripTopology::angularWidth(), CSCRadialStripTopology::detHeight(), CSCRadialStripTopology::originToIntersection(), phi, CSCRadialStripTopology::phiOfOneEdge(), funct::tan(), toLocal(), PV2DBase< T, PVType, FrameType >::x(), PV2DBase< T, PVType, FrameType >::y(), and CSCRadialStripTopology::yCentreOfStripPlane().

                                                                                      {
   // Local coordinates are (x,y). Coordinates along symmetry axes of strip
   // plane are (x',y'). These are rotated w.r.t. (x,y)
 
   // You might first think you could implement this as follows (cf. measurementPosition below):
   //  LocalPoint lpp = RST::localPosition(MP);
   //  return this->toLocal(lpp);
   // But this does not work because RST::localPosition makes use of stripAngle() - virtual - and thus
   // this is not the appropriate angle - it has the offset added, which is unwanted in this case!
   // So have to implement it directly...
 
   // 1st component of MP measures angular position within strip plane
   float phi = phiOfOneEdge() + mp.x() * angularWidth();
   // 2nd component of MP is fractional position along strip, with range +/-0.5,
   // so distance along strip, measured from mid-point of length of strip, is
   //     mp.y() * (length of strip). 
   // Distance in direction of coordinate y' is
   //    mp.y() * (length of strip) * cos(phi)
   // where phi is angle between strip and y' axis.
   // But (length of strip) = detHeight/cos(phi), so
   float yprime =  mp.y() * detHeight() + yCentreOfStripPlane();
   float xprime = ( originToIntersection() + yprime ) * tan ( phi );
   //  Rotate to (x,y)
   return toLocal(xprime, yprime);
 }

MeasurementPoint OffsetRadialStripTopology::measurementPosition ( const LocalPoint & lp ) const

virtual

MeasurementPoint corresponding to given LocalPoint

Reimplemented from CSCRadialStripTopology.

Definition at line 68 of file OffsetRadialStripTopology.cc.

References CSCRadialStripTopology::measurementPosition(), and toPrime().

                                                                                             {
   LocalPoint lpp = this->toPrime(lp); // in prime system, aligned with strip plane sym axes
   return CSCRadialStripTopology::measurementPosition(lpp); // now can use the base class method
 }

float OffsetRadialStripTopology::strip ( const LocalPoint & lp ) const

virtual

Strip in which a given LocalPoint lies. This is a float which represents the fractional strip position within the detector.
Returns zero if the LocalPoint falls at the extreme low edge of the detector or BELOW, and float(nstrips) if it falls at the extreme high edge or ABOVE.

Reimplemented from CSCRadialStripTopology.

Definition at line 73 of file OffsetRadialStripTopology.cc.

References CSCRadialStripTopology::angularWidth(), CSCRadialStripTopology::nstrips(), CSCRadialStripTopology::originToIntersection(), phi, CSCRadialStripTopology::phiOfOneEdge(), toPrime(), PV3DBase< T, PVType, FrameType >::x(), and PV3DBase< T, PVType, FrameType >::y().

Referenced by CSCGangedStripTopology::channel(), and CSCUngangedStripTopology::channel().

                                                                  {
   LocalPoint pnt = toPrime(lp);
   float phi = atan2( pnt.x(), pnt.y()+originToIntersection() );
   float fstrip = ( phi - phiOfOneEdge() ) / angularWidth();
   fstrip = ( fstrip>=0. ? fstrip : 0. );
   fstrip = ( fstrip<=nstrips() ? fstrip : nstrips() );
   return fstrip;
 }

float OffsetRadialStripTopology::stripAngle ( float strip ) const

virtual

Angle between strip and local y axis (measured clockwise from y axis)

Reimplemented from CSCRadialStripTopology.

Definition at line 82 of file OffsetRadialStripTopology.cc.

References CSCRadialStripTopology::angularWidth(), CSCRadialStripTopology::phiOfOneEdge(), and theStripOffset.

Referenced by CSCStripTopology::equationOfStrip().

                                                              {
   return ( phiOfOneEdge() + (strip+theStripOffset)*angularWidth() );
 }

virtual float OffsetRadialStripTopology::stripOffset ( void ) const

inlinevirtual

Fraction of a strip offset of layer relative to symmetry axis (local y). (This is an angular value)

Definition at line 33 of file OffsetRadialStripTopology.h.

References theStripOffset.

Referenced by operator<<().

33 { return theStripOffset; }

OffsetRadialStripTopology::theStripOffset

float theStripOffset

Definition: OffsetRadialStripTopology.h:102

LocalPoint OffsetRadialStripTopology::toLocal	(	float	xprime,
		float	yprime
	)		const

private

Transform from coordinates wrt strip plane symmetry axes to local coordinates

Definition at line 86 of file OffsetRadialStripTopology.cc.

References CSCRadialStripTopology::originToIntersection(), theCosOff, theSinOff, x, and y.

Referenced by localPosition().

                                                                               {
   float x =  theCosOff * xprime + theSinOff * yprime
              + originToIntersection() * theSinOff;
   float y = -theSinOff * xprime + theCosOff * yprime
              - originToIntersection() * (1. - theCosOff);
   return LocalPoint(x, y);
 }

LocalPoint OffsetRadialStripTopology::toPrime ( const LocalPoint & lp ) const

private

Transform from local coordinates to coordinates wrt strip plane symmetry axes

Definition at line 94 of file OffsetRadialStripTopology.cc.

References CSCRadialStripTopology::originToIntersection(), theCosOff, theSinOff, PV3DBase< T, PVType, FrameType >::x(), and PV3DBase< T, PVType, FrameType >::y().

Referenced by measurementPosition(), and strip().

                                                                         {
   float xprime = theCosOff * lp.x() - theSinOff * lp.y()
                   - originToIntersection() * theSinOff;
   float yprime = theSinOff * lp.x() + theCosOff * lp.y()
                   - originToIntersection() * (1. - theCosOff);
   return LocalPoint(xprime, yprime);
 }

Friends And Related Function Documentation

std::ostream& operator<<	(	std::ostream &	os,
		const OffsetRadialStripTopology &	orst
	)

friend

Definition at line 102 of file OffsetRadialStripTopology.cc.

 {
   os << "OffsetRadialStripTopology isa "
      <<  static_cast<const CSCRadialStripTopology&>( orst )
      << "fractional strip offset   " << orst.stripOffset()
      << "\ncos(angular offset)       " << orst.theCosOff
      << "\nsin(angular offset)       " << orst.theSinOff << std::endl;
   return os;
 }