/data/refman/pasoursint/CMSSW_6_1_2_SLHC2/src/RecoTracker/MeasurementDet/plugins/RecHitPropagator.h File Reference

#include "TrackingTools/TrajectoryState/interface/TrajectoryStateOnSurface.h"
#include "Geometry/CommonDetUnit/interface/GeomDet.h"

Go to the source code of this file.

Classes
class	RecHitPropagator
Functions
TrajectoryStateOnSurface	fastProp (const TrajectoryStateOnSurface &ts, const Plane &oPlane, const Plane &tPlane)

---

Function Documentation

TrajectoryStateOnSurface fastProp	(	const TrajectoryStateOnSurface &	ts,
		const Plane &	oPlane,
		const Plane &	tPlane
	)		[inline]

Definition at line 23 of file RecHitPropagator.h.

References TrajectoryStateOnSurface::charge(), TrajectoryStateOnSurface::curvilinearError(), delta, TrajectoryStateOnSurface::globalMomentum(), TrajectoryStateOnSurface::globalParameters(), TrajectoryStateOnSurface::globalPosition(), TrajectoryStateOnSurface::hasError(), Plane::localZ(), GlobalTrajectoryParameters::magneticField(), GloballyPositioned< T >::position(), Surface::toGlobal(), GloballyPositioned< T >::toLocal(), and PV3DBase< T, PVType, FrameType >::z().

                                                                                                                {
  GlobalVector gdir = ts.globalMomentum();
   
  double delta = tPlane.localZ(oPlane.position());
  LocalVector ldir = tPlane.toLocal(gdir);  // fast prop!
  LocalPoint lPos = tPlane.toLocal( ts.globalPosition());
  LocalPoint projectedPos = lPos - ldir * delta/ldir.z();
  // we can also patch it up as only the position-errors are used...
  GlobalTrajectoryParameters gp(tPlane.toGlobal(projectedPos),gdir,ts.charge(), &ts.globalParameters().magneticField());
  if (ts.hasError())
    return TrajectoryStateOnSurface(gp,ts.curvilinearError(),tPlane);
  else
    return TrajectoryStateOnSurface(gp,tPlane);


}