Belle II Software  release-08-01-10
Public Types | Public Member Functions | Private Attributes | List of all members
InPhi0CurvTanLBox Class Reference

Checker if a position is contained in a family of curves over phi0 and tan lambda. More...

#include <InPhi0CurvTanLBox.h>

Public Types

using HoughBox = Box< DiscretePhi0, DiscreteCurvWithArcLength2DCache, ContinuousTanL >
 The box to which this object correspondes.
 

Public Member Functions

 InPhi0CurvTanLBox (float curlCurv)
 Create a new box with the given curler curvature.
 
ESign getDistanceSign (const HoughBox &houghBox, float x, float y, float l, float dxdz, float dydz, ILayer iCLayer=-1) const
 Function that gives the sign of the distance from an observed drift circle to the sweeped object. More...
 

Private Attributes

float m_curlCurv
 Curler curvature - set to value greater zero to activate one arm exclusive finding.
 

Detailed Description

Checker if a position is contained in a family of curves over phi0 and tan lambda.

Definition at line 22 of file InPhi0CurvTanLBox.h.

Member Function Documentation

◆ getDistanceSign()

ESign getDistanceSign ( const HoughBox &  houghBox,
float  x,
float  y,
float  l,
float  dxdz,
float  dydz,
ILayer  iCLayer = -1 
) const
inline

Function that gives the sign of the distance from an observed drift circle to the sweeped object.

Two dimensional arc length

Definition at line 36 of file InPhi0CurvTanLBox.h.

43  {
44  const std::array<DiscretePhi0, 2>& phi0Vec = houghBox.getBounds<DiscretePhi0>();
45  const std::array<DiscreteCurvWithArcLength2DCache, 2>& curv =
46  houghBox.getBounds<DiscreteCurvWithArcLength2DCache>();
47  const std::array<ContinuousTanL, 2>& tanL = houghBox.getBounds<ContinuousTanL>();
48 
49  float r2 = x * x + y * y;
50 
51  std::array<float, 2> xRot;
52  xRot[0] = x * phi0Vec[0]->x() + y * phi0Vec[0]->y();
53  xRot[1] = x * phi0Vec[1]->x() + y * phi0Vec[1]->y();
54 
55  std::array<float, 2> yRotPlusL;
56  yRotPlusL[0] = -x * phi0Vec[0]->y() + y * phi0Vec[0]->x() + l;
57  yRotPlusL[1] = -x * phi0Vec[1]->y() + y * phi0Vec[1]->x() + l;
58 
59  // std::array<float, 2> dxdzRot;
60  // dxdzRot[0] = dxdz * phi0Vec[0]->x() + dydz * phi0Vec[0]->y();
61  // dxdzRot[1] = dxdz * phi0Vec[1]->x() + dydz * phi0Vec[1]->y();
62 
63  std::array<float, 2> dydzRot;
64  dydzRot[0] = -dxdz * phi0Vec[0]->y() + dydz * phi0Vec[0]->x();
65  dydzRot[1] = -dxdz * phi0Vec[1]->y() + dydz * phi0Vec[1]->x();
66 
67  const bool onlyPositiveArm = 0 < m_curlCurv;
68  if (onlyPositiveArm) {
69  // Reject hit if it is on the inward going branch but the curvature suggest it is no curler
70  if ((xRot[0] < 0) and (xRot[1] < 0)) return ESign::c_Invalid;
71  }
72 
74  std::array<float, 2> s;
75  s[0] = curv[0]->getArcLength2D(iCLayer, (xRot[0] < 0) and (xRot[1] < 0));
76  s[1] = curv[1]->getArcLength2D(iCLayer, (xRot[0] < 0) and (xRot[1] < 0));
77 
78  std::array<float, 2> r2TimesHalfCurv;
79  r2 -= l * l;
80  r2TimesHalfCurv[0] = r2 * (static_cast<float>(*(curv[0])) / 2.0);
81  r2TimesHalfCurv[1] = r2 * (static_cast<float>(*(curv[1])) / 2.0);
82 
83  // std::array<float, 4> xRotCor;
84  // xRotCor[0b00] = xRot[0] + dxdzRot[0] * s[0] * static_cast<float>(tanL[0]);
85  // xRotCor[0b01] = xRot[0] + dxdzRot[0] * s[0] * static_cast<float>(tanL[1]);
86  // xRotCor[0b10] = xRot[1] + dxdzRot[1] * s[1] * static_cast<float>(tanL[0]);
87  // xRotCor[0b11] = xRot[1] + dxdzRot[1] * s[1] * static_cast<float>(tanL[1]);
88 
89  // const std::array<float, 4>& sCor = xRotCor;
90 
91  std::array<float, 4> z;
92  z[0b00] = s[0] * static_cast<float>(tanL[0]);
93  z[0b01] = s[1] * static_cast<float>(tanL[0]);
94  z[0b10] = s[0] * static_cast<float>(tanL[1]);
95  z[0b11] = s[1] * static_cast<float>(tanL[1]);
96 
97  // Using binary notation encoding lower and upper box bounds to fill the flat array.
98  std::array<float, 8> dist;
99  dist[0b000] = r2TimesHalfCurv[0] - yRotPlusL[0] - dydzRot[0] * z[0b00];
100  dist[0b001] = r2TimesHalfCurv[0] - yRotPlusL[1] - dydzRot[1] * z[0b00];
101  dist[0b010] = r2TimesHalfCurv[1] - yRotPlusL[0] - dydzRot[0] * z[0b01];
102  dist[0b011] = r2TimesHalfCurv[1] - yRotPlusL[1] - dydzRot[1] * z[0b01];
103 
104  dist[0b100] = r2TimesHalfCurv[0] - yRotPlusL[0] - dydzRot[0] * z[0b10];
105  dist[0b101] = r2TimesHalfCurv[0] - yRotPlusL[1] - dydzRot[1] * z[0b10];
106  dist[0b110] = r2TimesHalfCurv[1] - yRotPlusL[0] - dydzRot[0] * z[0b11];
107  dist[0b111] = r2TimesHalfCurv[1] - yRotPlusL[1] - dydzRot[1] * z[0b11];
108 
109  return ESignUtil::common(dist);
110  }
Belle2::TrackFindingCDC::InPhi0CurvTanLBox::m_curlCurv
float m_curlCurv
Curler curvature - set to value greater zero to activate one arm exclusive finding.
Definition: InPhi0CurvTanLBox.h:114
Belle2::TrackFindingCDC::ESignUtil::common
static ESign common(ESign n1, ESign n2)
Check if two values have a common sign.
Definition: ESign.h:57
The documentation for this class was generated from the following file: