OffsetRadialStripTopology Class Reference

#include <OffsetRadialStripTopology.h>

Inheritance diagram for OffsetRadialStripTopology:

Public Member Functions
virtual int	channel (int strip) const =0
int	channel (const LocalPoint &lp) const override=0
LocalPoint	localPosition (float strip) const override
LocalPoint	localPosition (const MeasurementPoint &) const override
MeasurementPoint	measurementPosition (const LocalPoint &) const override
	OffsetRadialStripTopology (int numberOfStrips, float stripPhiPitch, float detectorHeight, float radialDistance, float stripOffset, float yCentre)
float	strip (const LocalPoint &) const override
float	stripAngle (float strip) const override
virtual float	stripOffset (void) const
	~OffsetRadialStripTopology () override
Public Member Functions inherited from CSCRadialStripTopology
float	angularWidth () const override
float	centreToIntersection () const override
	CSCRadialStripTopology (int ns, float aw, float dh, float r, float yAx=1.f, float yMid=0.)
float	detHeight () const override
LocalError	localError (float strip, float stripErr2) const override
LocalError	localError (const MeasurementPoint &, const MeasurementError &) const override
float	localPitch (const LocalPoint &) const override
float	localStripLength (const LocalPoint &) const override
MeasurementError	measurementError (const LocalPoint &, const LocalError &) const override
int	nearestStrip (const LocalPoint &) const override
int	nstrips () const override
float	originToIntersection () const override
float	phiOfOneEdge () const override
float	phiPitch (void) const override
float	stripLength () const override
float	xOfStrip (int strip, float y) const override
float	yAxisOrientation () const override
float	yCentreOfStripPlane () const override
float	yDistanceToIntersection (float y) const override
float	yExtentOfStripPlane () const override
	~CSCRadialStripTopology () override
Public Member Functions inherited from RadialStripTopology
virtual LocalError	localError (float strip, float stripErr2) const=0
virtual LocalError	localError (float strip, float stripErr2, const Topology::LocalTrackPred &) const
	conversion taking also the angle from the predicted track state More...
virtual LocalPoint	localPosition (float strip) const=0
virtual LocalPoint	localPosition (float strip, const Topology::LocalTrackPred &) const
	conversion taking also the predicted track state More...
float	pitch () const final
	~RadialStripTopology () override
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 LocalError	localError (const MeasurementPoint &, const MeasurementError &) const=0
virtual LocalError	localError (const MeasurementPoint &mp, const MeasurementError &me, const 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 (const MeasurementPoint &) const=0
virtual LocalPoint	localPosition (const MeasurementPoint &mp, const LocalTrackPred &) const
	conversion taking also the angle from the predicted track state 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...
	~StripTopology () override
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::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(), stripOffset(), 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;
}

~OffsetRadialStripTopology()

OffsetRadialStripTopology::~OffsetRadialStripTopology ( )

inlineoverride

Definition at line 30 of file OffsetRadialStripTopology.h.

{};

Member Function Documentation

channel() [1/2]

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.

Referenced by CSCLayerGeometry::channel().

channel() [2/2]

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

overridepure 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.

localPosition() [1/2]

LocalPoint OffsetRadialStripTopology::localPosition ( float  strip ) const

inlineoverridevirtual

LocalPoint for a given strip

Reimplemented from CSCRadialStripTopology.

Definition at line 39 of file OffsetRadialStripTopology.h.

References CSCRadialStripTopology::localPosition(), and strip().

                                                       {
    // 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);
  }

localPosition() [2/2]

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

overridevirtual

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);
}

measurementPosition()

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

overridevirtual

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
}

strip()

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

overridevirtual

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(), CSCUngangedStripTopology::channel(), CSCStripTopology::equationOfStrip(), CSCLayerGeometry::inside(), localPosition(), CSCLayerGeometry::strip(), and stripAngle().

                                                                 {
  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;
}

stripAngle()

float OffsetRadialStripTopology::stripAngle ( float  strip ) const

overridevirtual

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(), strip(), and theStripOffset.

Referenced by CSCStripTopology::equationOfStrip(), CSCLayerGeometry::intersectionOfStripAndWire(), and CSCLayerGeometry::stripAngle().

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

stripOffset()

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 35 of file OffsetRadialStripTopology.h.

References theStripOffset.

Referenced by FWRecoGeometryESProducer::addCSCGeometry(), OffsetRadialStripTopology(), operator<<(), and CSCLayerGeometry::stripOffset().

{ return theStripOffset; }

toLocal()

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);
}

toPrime()

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

private

Transform from local coordinates to coordinates wrt strip plane symmetry axes

Definition at line 92 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

operator<<

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

friend

Definition at line 98 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;
}

Member Data Documentation

theCosOff

float OffsetRadialStripTopology::theCosOff

private

Definition at line 105 of file OffsetRadialStripTopology.h.

Referenced by OffsetRadialStripTopology(), operator<<(), toLocal(), and toPrime().

theSinOff

float OffsetRadialStripTopology::theSinOff

private

Definition at line 106 of file OffsetRadialStripTopology.h.

Referenced by OffsetRadialStripTopology(), operator<<(), toLocal(), and toPrime().

theStripOffset

float OffsetRadialStripTopology::theStripOffset

private

Definition at line 104 of file OffsetRadialStripTopology.h.

Referenced by stripAngle(), and stripOffset().