13 #include <tracking/trackFindingVXD/filterMap/filterFramework/SelectionVariable.h>
14 #include <tracking/trackFindingVXD/filterMap/threeHitVariables/CircleCenterXY.h>
15 #include <tracking/trackFindingVXD/filterMap/twoHitVariables/CosDirectionXY.h>
16 #include <framework/geometry/B2Vector3.h>
19 #define HELIXPARAMETERFIT_NAME HelixParameterFit
31 template <
typename Po
intType >
39 static double value(
const PointType& outerHit,
const PointType& centerHit,
const PointType& innerHit)
42 B2Vector3D cCenter = CircleCenterXY<PointType>::value(outerHit, centerHit, innerHit);
44 B2Vector3D vecOuter2cC(outerHit.X() - cCenter.
X(), outerHit.Y() - cCenter.
Y(), outerHit.Z() - cCenter.
Z());
45 B2Vector3D vecCenter2cC(centerHit.X() - cCenter.
X(), centerHit.Y() - cCenter.
Y(), centerHit.Z() - cCenter.
Z());
46 B2Vector3D vecInner2cC(innerHit.X() - cCenter.
X(), innerHit.Y() - cCenter.
Y(), innerHit.Z() - cCenter.
Z());
48 double alfaAB = CosDirectionXY<B2Vector3D>::value(vecOuter2cC, vecCenter2cC);
49 double alfaBC = CosDirectionXY<B2Vector3D>::value(vecCenter2cC, vecInner2cC);
52 double result = (alfaAB * double(centerHit.Z() - innerHit.Z())) / (alfaBC *
double(outerHit.Z() - centerHit.Z()));
54 return (std::isnan(result) || std::isinf(result)) ?
double(0) : result;