MdcSagTraj.cxx

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//--------------------------------------------------------------------------
// File and Version Information:
//  $Id: MdcSagTraj.cxx,v 1.3 2009/12/17 00:38:40 zhangy Exp $
//
// Description:
//  Class MdcSagTraj
//
//
//
// Environment:
//  Software developed for the BaBar Detector at the SLAC B-Factory.
//
// Author List:
//  R. Stroili      originator
//
//
// Copyright Information:
//  Copyright (C) 1998  INFN & Padova University
//
// History:
//  Migration for BESIII MDC
//
//------------------------------------------------------------------------
 
//-----------------------
// This Class's Header --
//-----------------------
#include "MdcGeom/MdcSagTraj.h"
 
//-------------
// C Headers --
//-------------
extern "C" {}
 
//---------------
// C++ Headers --
//---------------
#include <assert.h>
 
//-------------------------------
// Collaborating Class Headers --
//-------------------------------
#include "MdcGeom/Trajectory.h"
 
//-----------------------------------------------------------------------
// Local Macros, Typedefs, Structures, Unions and Forward Declarations --
//-----------------------------------------------------------------------
 
//      ----------------------------------------
//      -- Public Function Member Definitions --
//      ----------------------------------------
 
//----------------
// Constructors --
//----------------
MdcSagTraj::MdcSagTraj( const double sag, const HepPoint3D& start, const HepPoint3D& stop )
    : TrkGeomTraj( 0.0, start.distance( stop ) ), _sag( sag ), _start( start ), _stop( stop ) {
  //_direction = stop - start;
  _direction = ( (CLHEP::Hep3Vector)stop ) - ( (CLHEP::Hep3Vector)start );
  _length    = _direction.mag();
  assert( _length != 0 );
 
  _direction.setMag( 1.0 );
  _a = _sag * 4. / ( _length * _length );
  _b = -_a * _length;
}
 
MdcSagTraj::MdcSagTraj( const MdcSagTraj& other )
    : TrkGeomTraj( 0.0, other._start.distance( other._stop ) )
    , _sag( other._sag )
    , _a( other._a )
    , _b( other._b )
    , _length( other._length )
    , _start( other._start )
    , _stop( other._stop )
    , _direction( other._direction ) {}
 
MdcSagTraj::~MdcSagTraj() { ; }
//-------------
// Methods   --
//-------------
MdcSagTraj* MdcSagTraj::clone() const { return new MdcSagTraj( *this ); }
 
//-------------
// Operators --
//-------------
//-----------------------------------------------------------------------------
MdcSagTraj& MdcSagTraj::operator=( const MdcSagTraj& other ) {
  if ( &other != this )
  {
    for ( int iend = 0; iend < 2; iend++ ) flightrange[iend] = other.flightrange[iend];
    _start     = other._start;
    _stop      = other._stop;
    _sag       = other._sag;
    _a         = other._a;
    _b         = other._b;
    _length    = other._length;
    _direction = other._direction;
  }
  return *this;
}
 
Hep3Vector MdcSagTraj::deviation( double flightlen ) const {
  // only correction in y
  //   Hep3Vector deviation(0., (_a*flightlen+_b)*flightlen, 0.);
  //   Hep3Vector deviaH(0.,cosh((flightlen-_length/2.)/_a_H)+_b_H,0.);
  //   return deviation;
  return Hep3Vector( 0., ( _a * flightlen + _b ) * flightlen, 0. );
}
 
HepPoint3D MdcSagTraj::position( double flightlen ) const {
  static HepPoint3D tmppos;
  tmppos = _start;
  // CHANGE   tmppos += _direction*flightlen;
  tmppos += (HepPoint3D)_direction * flightlen; // yzhang TEMP
  tmppos.setY( tmppos.y() + ( _a * flightlen + _b ) * flightlen );
  return tmppos;
}
 
Hep3Vector MdcSagTraj::direction( double flightlen ) const {
  if ( flightlen <= 0. ) return _direction;
  //    Hep3Vector dir =  _direction*flightlen + delDirect(flightlen);
  static Hep3Vector tmpdir;
  tmpdir = _direction * flightlen;
  //   register double newy = tmpdir.y() + 2.*_a*flightlen+_b;
  //   tmpdir.setY(newy);
  tmpdir.setY( tmpdir.y() + 2. * _a * flightlen + _b );
  //   tmpdir += delDirect(flightlen);
  tmpdir.setMag( 1.0 );
  return tmpdir;
}
 
Hep3Vector MdcSagTraj::delDirect( double /*flightlen*/ ) const {
  return Hep3Vector( 0., 2. * _a, 0. );
}
 
void MdcSagTraj::getInfo( double flightlen, HepPoint3D& pos, Hep3Vector& dir ) const {
  // std::cout<<"Dyz*"<<"MdcSagTraj01 "<<std::endl;//yzhang DEBUG
  // Written using +=, etc to avoid temporaries
  pos = _start;
  // CHANGE   pos += _direction*flightlen;
  pos += (HepPoint3D)_direction * flightlen;
 
  dir = _direction;
  if ( flightlen > 0. )
  {
    pos.setY( pos.y() + deltaY( flightlen ) );
    dir.setY( dir.y() + 2. * _a * flightlen + _b );
    dir.setMag( 1.0 );
  }
}
 
void MdcSagTraj::getInfo( double flightlen, HepPoint3D& pos, Hep3Vector& dir,
                          Hep3Vector& delDir ) const {
  //     std::cout<<"Dyz*"<<"MdcSagTraj011 "<<std::endl;//yzhang DEBUG
 
  pos = _start;
  // CHANGE   pos += _direction*flightlen ;
  pos += (HepPoint3D)_direction * flightlen;
 
  pos.setY( pos.y() + ( _a * flightlen + _b ) * flightlen );
 
  dir = _direction;
  dir.setY( dir.y() + 2 * _a * flightlen + _b );
  // Note: `dir' is on purpose not normalized (WDH, Jan 2003)
 
  delDir.setX( 0. );
  delDir.setY( 2. * _a );
  delDir.setZ( 0. );
}
 
double MdcSagTraj::curvature( double /*f*/ ) const { return _sag; }
 
double MdcSagTraj::distTo1stError( double flightlen, double tol, int pathDir ) const {
  double dtmp = pathDir * 2. * _a * flightlen + _b;
 
  return dtmp == 0. ? 9999.e4 : fabs( tol / dtmp );
}
 
double MdcSagTraj::distTo2ndError( double /*s*/, double /*tol*/, int /*pathDir*/ ) const {
  return 999.e4;
  // return _a==0. ? 999.e4 : tol/(2.*_a);
}
 
// Support Visitor pattern (see TrkGeomTraj.h)
void MdcSagTraj::accept( TrkGeomTrajVisitor& /*visitor*/ ) const {
  std::cout << "ErrMsg(error)"
            << "accept visitor NOT implemented yet" << std::endl;
}