HelixClass.h

#ifndef HELIXAR_H
#define HELIXAR_H 1
#include <vector>
#include "LineClass.h"
class HelixClass;

class HelixClass {
 public:

    HelixClass();
    ~HelixClass();
    void Initialize_VP(float * pos, float * mom, float q, float B);

    void Initialize_BZ(float xCentre, float yCentre, float radius, 
                                   float bZ, float phi0, float B, float signPz,
                                   float zBegin);
    void Initialize_Canonical(float phi0, float d0, float z0, float omega, 
                              float tanlambda, float B);
    const float * getMomentum();

    const float * getReferencePoint();

    float getPhi0();

    float getD0();

    float getZ0();

    float getOmega();

    float getTanLambda();

    float getPXY();


    float getXC();

    float getYC();


    float getRadius();   


    float getPointInXY(float x0, float y0, float ax, float ay, 
                              float * ref , float * point);

    float getPointInZ(float zLine, float * ref, float * point);

    float getDistanceToPoint(float * xPoint, float * Distance);

    float getDistanceToPoint(const float* xPoint, float distCut);
    float getDistanceToPoint(const std::vector<float>& xPoint, float distCut);

    float getPointOnCircle(float Radius, float * ref, float * point);

    float getDistanceToHelix(HelixClass * helix, float * pos, float * mom);

    void setHelixEdges(float * xStart, float * xEnd);

    float * getStartingPoint() {return _xStart;}

    float * getEndPoint() {return _xEnd;}
    
    float getBz();

    float getPhiZ();

    void getExtrapolatedMomentum(float * pos, float * momentum);

    float getCharge();

 private:    
    float _momentum[3]; // momentum @ ref point 
    float _referencePoint[3]; // coordinates @ ref point
    float _phi0; // phi0 in canonical parameterization 
    float _d0;   // d0 in canonical parameterisation
    float _z0;   // z0 in canonical parameterisation
    float _omega; // signed curvuture in canonical parameterisation
    float _tanLambda; // TanLambda 
    float _pxy; // Transverse momentum
    float _charge; // Particle Charge
    float _bField; // Magnetic field (assumed to point to Z>0)
    float _radius; // radius of circle in XY plane
    float _xCentre; // X of circle centre
    float _yCentre; // Y of circle centre
    float _phiRefPoint; // Phi w.r.t. (X0,Y0) of circle @ ref point
    float _phiAtPCA; // Phi w.r.t. (X0,Y0) of circle @ PCA 
    float _xAtPCA; // X @ PCA
    float _yAtPCA; // Y @ PCA
    float _pxAtPCA; // PX @ PCA
    float _pyAtPCA; // PY @ PCA
    float _phiMomRefPoint; // Phi of Momentum vector @ ref point
    float _const_pi; // PI
    float _const_2pi; // 2*PI
    float _const_pi2; // PI/2    
    float _FCT; // 2.99792458E-4
    float _xStart[3]; // Starting point of track segment
    float _xEnd[3]; // Ending point of track segment

    float _bZ;
    float _phiZ;

};


#endif