Belle II Software development
FastRaytracer.cc
1/**************************************************************************
2 * basf2 (Belle II Analysis Software Framework) *
3 * Author: The Belle II Collaboration *
4 * *
5 * See git log for contributors and copyright holders. *
6 * This file is licensed under LGPL-3.0, see LICENSE.md. *
7 **************************************************************************/
8
9#include <top/reconstruction_cpp/FastRaytracer.h>
10#include <framework/logging/Logger.h>
11#include <cmath>
12
13namespace Belle2 {
18 namespace TOP {
19
20 void FastRaytracer::propagate(const PhotonState& photon, bool averaging) const
21 {
22 clear();
23 m_photonStates.reserve(m_bars.size() * 2 + 2);
24 m_photonStates.push_back(photon);
25
26 int nbars = m_bars.size();
27 if (photon.getKz() > 0 and photon.getZ() > m_prism.zR) {
28 for (int i = 0; i < nbars; i++) {
29 const auto& bar = m_bars[i];
30 const auto& lastState = m_photonStates.back();
31 if (lastState.getZ() >= bar.zR) continue;
32 m_photonStates.push_back(lastState);
33 auto& newState = m_photonStates.back();
34 if (i < nbars - 1) {
35 newState.propagate(bar);
36 } else if (m_optics == c_SemiLinear) {
37 newState.propagateSemiLinear(bar, m_mirror);
38 } else {
39 newState.propagateExact(bar, m_mirror);
40 }
41 if (not newState.getPropagationStatus()) return;
42
43 m_Nxm += (m_Nxm % 2 == 0) ? newState.getNx() : -newState.getNx();
44 m_Nym += (m_Nym % 2 == 0) ? newState.getNy() : -newState.getNy();
45 }
46 }
47
48 for (int i = nbars - 1; i >= 0; i--) {
49 const auto& bar = m_bars[i];
50 const auto& lastState = m_photonStates.back();
51 if (lastState.getZ() <= bar.zL) continue;
52 m_photonStates.push_back(lastState);
53 auto& newState = m_photonStates.back();
54 newState.propagate(bar);
55 if (not newState.getPropagationStatus()) return;
56
57 m_Nxb += (m_Nxb % 2 == 0) ? newState.getNx() : -newState.getNx();
58 m_Nyb += (m_Nyb % 2 == 0) ? newState.getNy() : -newState.getNy();
59 }
60
61 const auto& lastState = m_photonStates.back();
62 m_photonStates.push_back(lastState);
63 auto& newState = m_photonStates.back();
64 newState.propagate(m_prism);
65 if (not newState.getPropagationStatus()) return;
66
67 if (averaging) {
68 m_extraStates.push_back(lastState);
69 auto& flippedState = m_extraStates.back().flipKy();
70 flippedState.propagate(m_prism);
71 if (not flippedState.getPropagationStatus()) return;
72 }
73
74 m_Nxe = newState.getNx();
75 m_Nye = newState.getNy();
76
77 m_status = true;
78 }
79
80 bool FastRaytracer::getTotalReflStatus(double cosTotal) const
81 {
82 for (const auto& photonState : m_photonStates) {
83 if (not photonState.getTotalReflStatus(cosTotal)) return false;
84 }
85 return true;
86 }
87
89 {
90 if (m_photonStates.empty()) return 0;
91 if (m_extraStates.empty()) return m_photonStates.back().getPropagationLen();
92 return (m_photonStates.back().getPropagationLen() + m_extraStates.back().getPropagationLen()) / 2;
93 }
94
96 {
97 if (m_photonStates.empty() or m_extraStates.empty()) return 0;
98 return (m_photonStates.back().getPropagationLen() - m_extraStates.back().getPropagationLen());
99 }
100
101 double FastRaytracer::getXD() const
102 {
103 if (m_photonStates.empty()) return 0;
104
105 double x = m_extraStates.empty() ?
106 m_photonStates.back().getXD() : (m_photonStates.back().getXD() + m_extraStates.back().getXD()) / 2;
107
108 for (int i = m_photonStates.size() - 2; i > 0; i--) {
109 const auto& photonState = m_photonStates[i];
110 if (photonState.getSegmentType() == PhotonState::c_MirrorSegment) break;
111 x = photonState.getUnfoldedX(x);
112 }
113 return x;
114 }
115
116
117 double FastRaytracer::getYD() const
118 {
119 if (m_photonStates.empty()) return 0;
120
121 double y = m_photonStates.back().getYD();
122 for (int i = m_photonStates.size() - 2; i > 0; i--) {
123 const auto& photonState = m_photonStates[i];
124 if (photonState.getSegmentType() == PhotonState::c_MirrorSegment) break;
125 y = photonState.getUnfoldedY(y);
126 }
127 return y;
128 }
129
130
132 {
133 if (m_photonStates.empty()) return 0;
134
135 double y = m_photonStates.back().getY();
136 for (int i = m_photonStates.size() - 1; i > 0; i--) {
137 const auto& photonState = m_photonStates[i];
138 if (photonState.getSegmentType() == PhotonState::c_MirrorSegment) break;
139 y = photonState.getUnfoldedY(y);
140 }
141 return y;
142 }
143
144
145 double FastRaytracer::getZD() const
146 {
147 if (m_photonStates.empty()) return 0;
148 if (m_extraStates.empty()) return m_photonStates.back().getZD();
149 return (m_photonStates.back().getZD() + m_extraStates.back().getZD()) / 2;
150 }
151
152
153 double FastRaytracer::getYB() const
154 {
155 if (m_photonStates.size() < 2) return 0;
156
157 int i0 = m_photonStates.size() - 2;
158 double y = m_photonStates[i0].getY();
159 for (int i = i0; i > 0; i--) {
160 const auto& photonState = m_photonStates[i];
161 if (photonState.getSegmentType() == PhotonState::c_MirrorSegment) break;
162 y = photonState.getUnfoldedY(y);
163 }
164 return y;
165 }
166
167
169 {
170 int Nx = m_Nxm;
171 Nx += (Nx % 2 == 0) ? m_Nxb : -m_Nxb;
172 Nx += (Nx % 2 == 0) ? m_Nxe : -m_Nxe;
173 return Nx;
174 }
175
176
178 {
179 int Ny = m_Nym;
180 Ny += (Ny % 2 == 0) ? m_Nyb : -m_Nyb;
181 Ny += (Ny % 2 == 0) ? m_Nye : -m_Nye;
182 return Ny;
183 }
184
186 {
187 int N = (m_Nye > 0) ? m_Nye / 2 : (std::abs(m_Nye) + 1) / 2;
188 return N;
189 }
190
191 } // TOP
193} // Belle2
int m_Nym
number of reflections in y before mirror
double getZD() const
Returns unfolded position in z of virtual Detector plane.
double getPropagationLen() const
Returns total propagation length since initial position.
double getInPlaneYD() const
Returns unfolded position in y such that the prism unfolded windows are turned over into the real Det...
std::vector< PhotonState > m_photonStates
photon states at propagation steps
void propagate(const PhotonState &photon, bool averaging=false) const
Propagate photon to photo-detector plane.
int m_Nxm
number of reflections in x before mirror
int getNx() const
Returns signed number of reflections in x.
double getYB() const
Returns unfolded position in y at Bar-prism-connection plane.
double getYD() const
Returns unfolded position in y at virtual Detector plane.
bool getTotalReflStatus(double cosTotal) const
Returns total internal reflection status.
bool m_status
propagation status
int m_Nxe
number of reflections in x inside prism
int getNy() const
Returns signed number of reflections in y.
int getNys() const
Returns number of reflections on slanted prism surface.
double getPropagationLenDelta() const
Returns total propagation length difference between true and flipped prism Reliable only if propagati...
int m_Nyb
number of reflections in y after mirror and before prism
int m_Nxb
number of reflections in x after mirror and before prism
int m_Nye
number of reflections in y inside prism
void clear() const
Clear mutable variables.
std::vector< PhotonState > m_extraStates
extra storage
double getXD() const
Returns unfolded position in x at virtual Detector plane.
State of the Cerenkov photon in the quartz optics.
Definition PhotonState.h:27
double getZ() const
Returns position in z.
@ c_MirrorSegment
mirror segment
Definition PhotonState.h:37
double getKz() const
Returns direction in z.
EOptics m_optics
spherical mirror optics
@ c_SemiLinear
semi-linear approximation
Mirror m_mirror
spherical mirror geometry data
Prism m_prism
prism geometry data
std::vector< BarSegment > m_bars
geometry data of bar segments
Abstract base class for different kinds of events.