CSCWireGeometry Class Reference

#include <CSCWireGeometry.h>

Inheritance diagram for CSCWireGeometry:

Public Member Functions
virtual CSCWireGeometry *	clone () const =0
	CSCWireGeometry (double wireSpacing, double yOfFirstWire, double narrowWidthOfPlane, double wideWidthOfPlane, double lengthOfPlane)
std::pair< float, float >	equationOfWire (float wire) const
LocalPoint	intersection (float m1, float c1, float m2, float c2) const
double	lengthOfPlane () const
double	narrowWidthOfPlane () const
virtual int	nearestWire (const LocalPoint &lp) const =0
double	wideWidthOfPlane () const
virtual float	wireAngle () const =0
std::pair< LocalPoint, LocalPoint >	wireEnds (float wire) const
double	wireSpacing () const
std::vector< float >	wireValues (float wire) const
std::pair< float, float >	yLimitsOfWirePlane () const
double	yOfFirstWire () const
virtual float	yOfWire (float wire, float x=0.) const =0
virtual	~CSCWireGeometry ()

Private Attributes
double	theLengthOfPlane
double	theNarrowWidthOfPlane
double	theWideWidthOfPlane
double	theWireSpacing
double	theYOfFirstWire

Detailed Description

An ABC defining interface for geometry related to angle which wires of a detector modelled by a WireTopology make with the local x axis.

Author

Tim Cox

Definition at line 17 of file CSCWireGeometry.h.

Constructor & Destructor Documentation

virtual CSCWireGeometry::~CSCWireGeometry ( )

inlinevirtual

Definition at line 19 of file CSCWireGeometry.h.

{}

CSCWireGeometry::CSCWireGeometry ( double  wireSpacing, double  yOfFirstWire, double  narrowWidthOfPlane, double  wideWidthOfPlane, double  lengthOfPlane  )

inline

Constructor from wire spacing (in cm)

Definition at line 24 of file CSCWireGeometry.h.

      : theWireSpacing(wireSpacing),
        theYOfFirstWire(yOfFirstWire),
        theNarrowWidthOfPlane(narrowWidthOfPlane),
        theWideWidthOfPlane(wideWidthOfPlane),
        theLengthOfPlane(lengthOfPlane) {}

Member Function Documentation

virtual CSCWireGeometry* CSCWireGeometry::clone ( ) const

pure virtual

Allow proper copying of derived classes via base pointer

Implemented in CSCNonslantedWireGeometry, and CSCSlantedWireGeometry.

Referenced by CSCWireTopology::CSCWireTopology(), and CSCWireTopology::operator=().

std::pair< float, float > CSCWireGeometry::equationOfWire

(

float

wire

)

const

Return slope and intercept of straight line representing a wire in 2-dim local coordinates.

The return value is a pair p with p.first = m, p.second = c, where y=mx+c.

Definition at line 166 of file CSCWireGeometry.cc.

References LogTrace, funct::tan(), wireAngle(), and yOfWire().

Referenced by CSCWireTopology::equationOfWire().

                                                                      {
  const float fprec = 1.E-06;

  // slope of wire
  float wangle = wireAngle();
  float mw = 0;
  if (fabs(wangle) > fprec)
    mw = tan(wangle);

  // intercept of wire
  float cw = yOfWire(wire);

  LogTrace("CSCWireGeometry|CSC") << "CSCWireGeometry: wire=" << wire << ", wire angle = " << wangle
                                  << ", intercept on y axis=" << cw;

  return std::pair<float, float>(mw, cw);
}

LocalPoint CSCWireGeometry::intersection	(	float	m1,
		float	c1,
		float	m2,
		float	c2
	)		const

2D point of intersection of two straight lines defined by
y = m1*x + c1 and y = m2*x + c2
(in local coordinates x, y)

Definition at line 7 of file CSCWireGeometry.cc.

References alignmentValidation::c1, x, and y.

Referenced by wireEnds().

                                                                                     {
  // Calculate the point of intersection of two straight lines (in 2-dim)
  // BEWARE! Do not call with m1 = m2 ! No trapping !

  float x = (c2 - c1) / (m1 - m2);
  float y = (m1 * c2 - m2 * c1) / (m1 - m2);
  return LocalPoint(x, y);
}

double CSCWireGeometry::lengthOfPlane ( ) const

inline

Extent of wire plane along long axis of trapezoid

Definition at line 55 of file CSCWireGeometry.h.

References theLengthOfPlane.

Referenced by CSCWireTopology::lengthOfPlane(), wireEnds(), and yLimitsOfWirePlane().

{ return theLengthOfPlane; }

double CSCWireGeometry::narrowWidthOfPlane ( ) const

inline

Extent of wire plane at narrow end of trapezoid

Definition at line 45 of file CSCWireGeometry.h.

References theNarrowWidthOfPlane.

Referenced by CSCWireTopology::narrowWidthOfPlane(), wireEnds(), and yLimitsOfWirePlane().

{ return theNarrowWidthOfPlane; }

virtual int CSCWireGeometry::nearestWire ( const LocalPoint &  lp ) const

pure virtual

The nearest (virtual) wire to a given LocalPoint. Beware that this wire might not exist or be read out!

Implemented in CSCNonslantedWireGeometry, and CSCSlantedWireGeometry.

Referenced by CSCWireTopology::channel(), and CSCWireTopology::nearestWire().

double CSCWireGeometry::wideWidthOfPlane ( ) const

inline

Extent of wire plane at wide end of trapezoid

Definition at line 50 of file CSCWireGeometry.h.

References theWideWidthOfPlane.

Referenced by CSCWireTopology::wideWidthOfPlane(), and wireEnds().

{ return theWideWidthOfPlane; }

virtual float CSCWireGeometry::wireAngle ( ) const

pure virtual

The angle of the wires w.r.t local x axis (in radians)

Implemented in CSCNonslantedWireGeometry, and CSCSlantedWireGeometry.

Referenced by equationOfWire(), CSCWireTopology::wireAngle(), wireEnds(), and yLimitsOfWirePlane().

std::pair< LocalPoint, LocalPoint > CSCWireGeometry::wireEnds

(

float

wire

)

const

Return 2-dim local coords of the two ends of a wire

The returned value is a pair of LocalPoints.

Definition at line 32 of file CSCWireGeometry.cc.

References alignmentValidation::c1, hcalSimParameters_cfi::hb, mps_fire::i, intersection(), dqmiolumiharvest::j, lengthOfPlane(), LogTrace, callgraph::m2, narrowWidthOfPlane(), funct::tan(), wideWidthOfPlane(), wireAngle(), PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), yOfFirstWire(), and yOfWire().

Referenced by CSCWireTopology::wireEnds(), and wireValues().

                                                                          {
  // return local (x, y) of each end of wire.
  // If wire does not intersect active area set all values to 0.

  const float fprec = 1.E-06;

  // slope of wire
  float wangle = wireAngle();
  float mw = 0;
  if (fabs(wangle) > fprec)
    mw = tan(wireAngle());

  // intercept of wire
  float cw = yOfWire(wire);

  LogTrace("CSCWireGeometry|CSC") << "CSCWireGeometry: wire=" << wire << ", wire angle = " << wangle
                                  << ", intercept on y axis=" << cw;

  // Find extent of wire plane
  double ww = wideWidthOfPlane();
  double nw = narrowWidthOfPlane();
  double len = lengthOfPlane();

  // slope & intercept of line defining one non-parallel edge of wire-plane trapezoid
  float m1 = 2. * len / (ww - nw);
  float c1 = 0.;
  if (fabs(wangle) < fprec) {
    c1 = yOfFirstWire() - nw * len / (ww - nw);  // non-ME11
  } else {
    c1 = -len / 2. - nw * len / (ww - nw);  // ME11
  }

  // slope & intercept of other non-parallel edge of wire-plane trapezoid
  float m2 = -m1;
  float c2 = c1;

  // wire intersects edge 1 at
  LocalPoint pw1 = intersection(mw, cw, m1, c1);
  // wire intersects edge 2 at
  LocalPoint pw2 = intersection(mw, cw, m2, c2);

  float x1 = pw1.x();
  float y1 = pw1.y();

  float x2 = pw2.x();
  float y2 = pw2.y();

  LogTrace("CSCWireGeometry|CSC") << "CSCWireGeometry: wire intersects edges of plane at "
                                  << "\n  x1=" << x1 << " y1=" << y1 << " x2=" << x2 << " y2=" << y2;

  // WIRES ARE NOT TILTED?

  if (fabs(wangle) < fprec) {
    LogTrace("CSCWireGeometry|CSC") << "CSCWireGeometry: wires are not tilted ";
    return std::pair<LocalPoint, LocalPoint>(LocalPoint(x1, y1), LocalPoint(x2, y2));
  }

  // WIRES ARE TILTED

  // ht and hb will be used to check where wire intersects edges of wire plane
  float ht = ww / 2.;
  float hb = nw / 2.;
  float mt = 0.;         // slope of top edge
  float mb = 0.;         //slope of bottom edge
  float cb = -len / 2.;  // intercept bottom edge of wire plane
  float ct = len / 2.;   // intercept top edge of wire plane

  LogTrace("CSCWireGeometry|CSC") << "CSCWireGeometry: slopes & intercepts "
                                  << "\n  mt=" << mt << " ct=" << ct << " mb=" << mb << " cb=" << cb << "\n  m1=" << m1
                                  << " c1=" << c1 << " m2=" << m2 << " c2=" << c2 << "\n  mw=" << mw << " cw=" << cw;

  // wire intersects top edge at
  LocalPoint pwt = intersection(mw, cw, mt, ct);
  // wire intersects bottom edge at
  LocalPoint pwb = intersection(mw, cw, mb, cb);

  // get the local coordinates
  float xt = pwt.x();
  float yt = pwt.y();

  float xb = pwb.x();
  float yb = pwb.y();

  LogTrace("CSCWireGeometry|CSC") << "CSCWireGeometry: wire intersects top & bottom of wire plane at "
                                  << "\n  xt=" << xt << " yt=" << yt << " xb=" << xb << " yb=" << yb;

  float xWireEnd[4], yWireEnd[4];

  int i = 0;
  if (fabs(x1) >= hb && fabs(x1) <= ht) {
    // wire does intersect side edge 1 of wire plane
    xWireEnd[i] = x1;
    yWireEnd[i] = y1;
    i++;
  }
  if (fabs(xb) <= hb) {
    // wire does intersect bottom edge of wire plane
    xWireEnd[i] = xb;
    yWireEnd[i] = yb;
    i++;
  }
  if (fabs(x2) >= hb && fabs(x2) <= ht) {
    // wire does intersect side edge 2 of wire plane
    xWireEnd[i] = x2;
    yWireEnd[i] = y2;
    i++;
  }
  if (fabs(xt) <= ht) {
    // wire does intersect top edge of wire plane
    xWireEnd[i] = xt;
    yWireEnd[i] = yt;
    i++;
  }

  if (i != 2) {
    // the wire does not intersect the wire plane (!)

    LogTrace("CSCWireGeometry|CSC") << "CSCWireGeometry: wire does not intersect wire plane!!";
    //     throw cms::Exception("BadCSCGeometry") << "the wire has " << i <<
    //       " ends!" << "\n";

    return std::pair<LocalPoint, LocalPoint>(LocalPoint(0., 0.), LocalPoint(0., 0.));
  }

  LogTrace("CSCWireGeometry|CSC") << "CSCWireGeometry: ME11 wire ends ";
  for (int j = 0; j < i; j++) {
    LogTrace("CSCWireGeometry|CSC") << "  x = " << xWireEnd[j] << " y = " << yWireEnd[j];
  }

  return std::pair<LocalPoint, LocalPoint>(LocalPoint(xWireEnd[0], yWireEnd[0]), LocalPoint(xWireEnd[1], yWireEnd[1]));
}

double CSCWireGeometry::wireSpacing ( ) const

inline

The spacing between wires (cm)

Definition at line 35 of file CSCWireGeometry.h.

References theWireSpacing.

Referenced by CSCSlantedWireGeometry::nearestWire(), CSCNonslantedWireGeometry::nearestWire(), CSCWireTopology::wireSpacing(), CSCSlantedWireGeometry::yOfWire(), and CSCNonslantedWireGeometry::yOfWire().

{ return theWireSpacing; }

std::vector< float > CSCWireGeometry::wireValues

(

float

wire

)

const

Return mid-point of a wire in local coordinates, and its length across the chamber volume, in a vector as x, y, length

Definition at line 16 of file CSCWireGeometry.cc.

References visDQMUpload::buf, mathSSE::sqrt(), and wireEnds().

Referenced by CSCWireTopology::wireValues().

                                                             {
  // return x and y of mid-point of wire, and length of wire, as 3-dim vector.
  // If wire does not intersect active area the returned vector is filled with 0's.

  std::pair<LocalPoint, LocalPoint> ends = wireEnds(wire);

  std::vector<float> buf(3);  // note all elem init to 0

  buf[0] = (ends.first.x() + ends.second.x()) / 2.;  // x is first elem of first & second pairs
  buf[1] = (ends.first.y() + ends.second.y()) / 2.;  // y is second elem of first & second pairs
  float d2 = (ends.first.x() - ends.second.x()) * (ends.first.x() - ends.second.x()) +
             (ends.first.y() - ends.second.y()) * (ends.first.y() - ends.second.y());
  buf[2] = sqrt(d2);
  return buf;
}

std::pair< float, float > CSCWireGeometry::yLimitsOfWirePlane

(

)

const

Return pair containing y extremes of wire-plane: p.first = low y, p.second= high y

This is supposed to approximate the 'sensitive' region covered by wires (and strips) but there is no sophisticated handling of edge effects, or attempt to estimate a precise region overlapped by both wires and strips.

Definition at line 186 of file CSCWireGeometry.cc.

References funct::abs(), lengthOfPlane(), narrowWidthOfPlane(), funct::tan(), wireAngle(), and yOfFirstWire().

Referenced by CSCWireTopology::insideYOfWirePlane(), and CSCWireTopology::restrictToYOfWirePlane().

                                                                {
  const float fprec = 0.1;      // wire angle is either 0 or 29 degrees = 0.506 rads
  float ylow = yOfFirstWire();  // non-ME11 chambers
  float wangle = wireAngle();
  if (fabs(wangle) > fprec) {
    ylow += tan(std::abs(wangle)) * narrowWidthOfPlane() / 2.;  // correction for ME11
  }
  float yhigh = ylow + lengthOfPlane();  // add extent of wire plane in y

  return std::pair<float, float>(ylow, yhigh);
}

double CSCWireGeometry::yOfFirstWire ( ) const

inline

The local y of the first wire

Definition at line 40 of file CSCWireGeometry.h.

References theYOfFirstWire.

Referenced by CSCNonslantedWireGeometry::nearestWire(), wireEnds(), yLimitsOfWirePlane(), and CSCNonslantedWireGeometry::yOfWire().

{ return theYOfFirstWire; }

virtual float CSCWireGeometry::yOfWire ( float  wire, float  x = 0.  ) const

pure virtual

Local y of a given wire 'number' (float) at given x

Implemented in CSCNonslantedWireGeometry, and CSCSlantedWireGeometry.

Referenced by equationOfWire(), wireEnds(), CSCWireTopology::yOfWire(), and CSCWireTopology::yOfWireGroup().

Member Data Documentation

double CSCWireGeometry::theLengthOfPlane

private

Definition at line 116 of file CSCWireGeometry.h.

Referenced by lengthOfPlane().

double CSCWireGeometry::theNarrowWidthOfPlane

private

Definition at line 114 of file CSCWireGeometry.h.

Referenced by narrowWidthOfPlane().

double CSCWireGeometry::theWideWidthOfPlane

private

Definition at line 115 of file CSCWireGeometry.h.

Referenced by wideWidthOfPlane().

double CSCWireGeometry::theWireSpacing

private

Definition at line 112 of file CSCWireGeometry.h.

Referenced by wireSpacing().

double CSCWireGeometry::theYOfFirstWire

private

Definition at line 113 of file CSCWireGeometry.h.

Referenced by yOfFirstWire().