SeedFromConsecutiveHitsStraightLineCreator.cc

Go to the documentation of this file.

#include "SeedFromConsecutiveHitsStraightLineCreator.h"
#include "RecoTracker/TkTrackingRegions/interface/TrackingRegion.h"



bool SeedFromConsecutiveHitsStraightLineCreator::initialKinematic(GlobalTrajectoryParameters & kine,
                                  const SeedingHitSet & hits) const {

  const TransientTrackingRecHit::ConstRecHitPointer& tth1 = hits[0];
  const TransientTrackingRecHit::ConstRecHitPointer& tth2 = hits[1];

  const GlobalPoint& vertexPos = region->origin();

  // Assume initial state is straight line passing through beam spot
  // with direction given by innermost two seed hits (with big uncertainty)
  GlobalVector initMomentum(tth2->globalPosition() - tth1->globalPosition());
  double rescale = 1000./initMomentum.perp();
  initMomentum *= rescale; // set to approximately infinite momentum
  TrackCharge q = 1; // irrelevant, since infinite momentum
  kine = GlobalTrajectoryParameters(vertexPos, initMomentum, q, &*bfield);

  return (filter ? filter->compatible(hits, kine, *region) : true); 

}