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#ifndef ConeDefinition_h
#define ConeDefinition_h
#include "DataFormats/GeometryVector/interface/GlobalPoint.h"
#include "DataFormats/GeometryVector/interface/GlobalVector.h"
#include "CommonTools/UtilAlgos/interface/DeltaR.h"
inline double getDistInPlaneSimple(const GlobalPoint caloPoint, const GlobalPoint rechitPoint) {
// Simplified version of getDistInPlane
// Assume track direction is origin -> point of hcal intersection
const GlobalVector caloIntersectVector(caloPoint.x(), caloPoint.y(), caloPoint.z());
const GlobalVector caloIntersectUnitVector = caloIntersectVector.unit();
const GlobalVector rechitVector(rechitPoint.x(), rechitPoint.y(), rechitPoint.z());
const GlobalVector rechitUnitVector = rechitVector.unit();
double dotprod = caloIntersectUnitVector.dot(rechitUnitVector);
double rechitdist = caloIntersectVector.mag() / dotprod;
const GlobalVector effectiveRechitVector = rechitdist * rechitUnitVector;
const GlobalPoint effectiveRechitPoint(
effectiveRechitVector.x(), effectiveRechitVector.y(), effectiveRechitVector.z());
GlobalVector distance_vector = effectiveRechitPoint - caloPoint;
if (dotprod > 0.) {
return distance_vector.mag();
} else {
return 999999.;
}
}
inline double getDistInPlaneTrackDir(const GlobalPoint caloPoint,
const GlobalVector caloVector,
const GlobalPoint rechitPoint) {
// Simplified version of getDistInPlane : no cone "within" Hcal, but
// don't assume track direction is origin -> point of hcal
// intersection.
const GlobalVector caloIntersectVector(caloPoint.x(), caloPoint.y(),
caloPoint.z()); //p
const GlobalVector caloUnitVector = caloVector.unit();
const GlobalVector rechitVector(rechitPoint.x(), rechitPoint.y(), rechitPoint.z());
const GlobalVector rechitUnitVector = rechitVector.unit();
double dotprod_denominator = caloUnitVector.dot(rechitUnitVector);
double dotprod_numerator = caloUnitVector.dot(caloIntersectVector);
double rechitdist = dotprod_numerator / dotprod_denominator;
// double rechitdist=caloIntersectVector.dot(rechitUnitVector);
const GlobalVector effectiveRechitVector = rechitdist * rechitUnitVector;
const GlobalPoint effectiveRechitPoint(
effectiveRechitVector.x(), effectiveRechitVector.y(), effectiveRechitVector.z());
GlobalVector distance_vector = effectiveRechitPoint - caloPoint;
if (dotprod_denominator > 0. && dotprod_numerator > 0.) {
return distance_vector.mag();
} else {
return 999999.;
}
}
inline double getDistInPlane(const GlobalVector trackDirection,
const GlobalPoint caloPoint,
const GlobalPoint rechitPoint,
double coneHeight) {
// The iso track candidate hits the Calo (Ecal or Hcal) at "caloPoint"
// with direction "trackDirection".
// "rechitPoint" is the position of the rechit. We only care about
// the direction of the rechit.
// Consider the rechitPoint as characterized by angles theta and phi
// wrt the origin which points at the calo cell of the rechit. In
// some sense the distance along the line theta/phi is arbitrary. A
// simplified choice might be to put the rechit at the surface of
// the Hcal. Our approach is to see whether/where this line
// intersects a cone of height "coneHeight" with vertex at caloPoint
// aligned with trackDirection.
// To that end, this function returns the distance between the
// center of the base of the cone and the intersection of the rechit
// line and the plane that contains the base of the cone. This
// distance is compared with the radius of the cone outside this
// function.
// Make vector of length cone height along track direction
const GlobalVector heightVector = trackDirection * coneHeight;
// Make vector from origin to point where iso track intersects the
// calorimeter.
const GlobalVector caloIntersectVector(caloPoint.x(), caloPoint.y(), caloPoint.z());
// Make vector from origin to point in center of base of cone
const GlobalVector coneBaseVector = heightVector + caloIntersectVector;
// Make point in center of base of cone
const GlobalPoint coneBasePoint(coneBaseVector.x(), coneBaseVector.y(), coneBaseVector.z());
// Make unit vector pointing at rechit.
const GlobalVector rechitVector(rechitPoint.x(), rechitPoint.y(), rechitPoint.z());
const GlobalVector rechitDirection = rechitVector.unit();
// Find distance "r" along "rechit line" (with angles theta2 and
// phi2) where line intersects plane defined by base of cone.
// Definition plane of that contains base of cone:
// trackDirection.x() (x - coneBaseVector.x()) +
// trackDirection.y() (y - coneBaseVector.y()) +
// trackDirection.z() (z - coneBaseVector.z()) = 0
// Point P_{rh} where rechit line intersects plane:
// (rechitdist sin(theta2) cos(phi2),
// rechitdist sin(theta2) cos(phi2),
// rechitdist cos(theta2))
// Substitute P_{rh} into equation for plane and solve for rechitdist.
// rechitDist turns out to be the ratio of dot products:
double rechitdist = trackDirection.dot(coneBaseVector) / trackDirection.dot(rechitDirection);
// Now find distance between point at center of cone base and point
// where the "rechit line" intersects the plane defined by the base
// of the cone; i.e. the effectiveRecHitPoint.
const GlobalVector effectiveRechitVector = rechitdist * rechitDirection;
const GlobalPoint effectiveRechitPoint(
effectiveRechitVector.x(), effectiveRechitVector.y(), effectiveRechitVector.z());
GlobalVector distance_vector = effectiveRechitPoint - coneBasePoint;
return distance_vector.mag();
}
#endif
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