Additiona TOF data members (S.Arcelli)
[u/mrichter/AliRoot.git] / FMD / AliFMDRing.cxx
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4347b38f 1/**************************************************************************
c4bcfd14 2 * Copyright(c) 2004, ALICE Experiment at CERN, All rights reserved. *
4347b38f 3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
15
16/* $Id$ */
17
c4bcfd14 18//__________________________________________________________________
4347b38f 19//
20// Utility class to help implement collection of FMD modules into
1a1fdef7 21// rings. This is used by AliFMDDetector and AliFMDGeometry.
4347b38f 22//
1a1fdef7 23// The AliFMDGeometry object owns the AliFMDRing objects, and the
24// AliFMDDetector objects reference these. That is, the AliFMDRing
25// objects are share amoung the AliFMDDetector objects.
4347b38f 26//
27// Latest changes by Christian Holm Christensen
28//
5edc364e 29
56b1929b 30#include <AliLog.h> // ALILOG_H
e802be3e 31#include "AliFMDRing.h" // ALIFMDRING_H
56b1929b 32#include <TMath.h> // ROOT_TMath
56b1929b 33#include <TVector2.h> // ROOT_TVector2
4347b38f 34
1a1fdef7 35//====================================================================
e6a0eb08 36ClassImp(AliFMDRing)
1a1fdef7 37#if 0
38 ; // This is here to keep Emacs for indenting the next line
39#endif
4347b38f 40
41//____________________________________________________________________
1a1fdef7 42AliFMDRing::AliFMDRing(Char_t id)
43 : TNamed(Form("FMD%c", id), "Forward multiplicity ring"),
44 fId(id),
45 fVerticies(0)
4347b38f 46{
088f8e79 47 // CTOR
1a1fdef7 48 SetBondingWidth();
49 SetWaferRadius();
50 SetSiThickness();
51 SetLegRadius();
52 SetLegLength();
53 SetLegOffset();
54 SetModuleSpacing();
55 SetPrintboardThickness();
4ac75127 56 SetCopperThickness();
57 SetChipThickness();
a1f80595 58 SetSpacing();
4347b38f 59
1a1fdef7 60 if (fId == 'I' || fId == 'i') {
61 SetLowR(4.3);
62 SetHighR(17.2);
63 SetTheta(36/2);
64 SetNStrips(512);
65 }
66 else if (fId == 'O' || fId == 'o') {
67 SetLowR(15.6);
68 SetHighR(28.0);
69 SetTheta(18/2);
70 SetNStrips(256);
4347b38f 71 }
4347b38f 72}
73
4347b38f 74//____________________________________________________________________
75void
1a1fdef7 76AliFMDRing::Init()
4347b38f 77{
088f8e79 78 // Initialize
1a1fdef7 79 Double_t tanTheta = TMath::Tan(fTheta * TMath::Pi() / 180.);
80 Double_t tanTheta2 = TMath::Power(tanTheta,2);
81 Double_t r2 = TMath::Power(fWaferRadius,2);
82 Double_t yA = tanTheta * fLowR;
83 Double_t lr2 = TMath::Power(fLowR, 2);
84 Double_t hr2 = TMath::Power(fHighR,2);
85 Double_t xD = fLowR + TMath::Sqrt(r2 - tanTheta2 * lr2);
86 Double_t xD2 = TMath::Power(xD,2);
87 Double_t yB = TMath::Sqrt(r2 - hr2 + 2 * fHighR * xD - xD2);
88 Double_t xC = ((xD + TMath::Sqrt(-tanTheta2 * xD2 + r2
89 + r2 * tanTheta2))
90 / (1 + tanTheta2));
91 Double_t yC = tanTheta * xC;
4347b38f 92
1a1fdef7 93 fVerticies.Expand(6);
94 fVerticies.AddAt(new TVector2(fLowR, -yA), 0);
95 fVerticies.AddAt(new TVector2(xC, -yC), 1);
96 fVerticies.AddAt(new TVector2(fHighR, -yB), 2);
97 fVerticies.AddAt(new TVector2(fHighR, yB), 3);
98 fVerticies.AddAt(new TVector2(xC, yC), 4);
99 fVerticies.AddAt(new TVector2(fLowR, yA), 5);
100
54e415a8 101 // A's length. Corresponds to distance from nominal beam line to the
102 // cornor of the active silicon element.
103 fMinR = GetVertex(5)->Mod();
104 // A's length. Corresponds to distance from nominal beam line to the
105 // cornor of the active silicon element.
106 fMaxR = fHighR;
107
1a1fdef7 108 fRingDepth = (fSiThickness + fPrintboardThickness
4ac75127 109 + fCopperThickness + fChipThickness
110 + fLegLength + fModuleSpacing + fSpacing);
4347b38f 111}
112
113//____________________________________________________________________
1a1fdef7 114TVector2*
115AliFMDRing::GetVertex(Int_t i) const
4347b38f 116{
088f8e79 117 // Get the i'th vertex of polygon shape
1a1fdef7 118 return static_cast<TVector2*>(fVerticies.At(i));
4347b38f 119}
120
121//____________________________________________________________________
bf000c32 122Double_t
123AliFMDRing::GetStripRadius(UShort_t strip) const
124{
125 // Return the nominal strip radius
126 Double_t rmax = GetMaxR();
127 Double_t stripoff = GetMinR();
128 Double_t dstrip = (rmax - stripoff) / GetNStrips();
129 return (strip + .5) * dstrip + stripoff; // fLowR
130}
131
132//____________________________________________________________________
1a1fdef7 133void
134AliFMDRing::Detector2XYZ(UShort_t sector,
135 UShort_t strip,
136 Double_t& x,
137 Double_t& y,
138 Double_t& z) const
4347b38f 139{
088f8e79 140 // Translate detector coordinates (this,sector,strip) to global
141 // coordinates (x,y,z)
1a1fdef7 142 if (sector >= GetNSectors()) {
143 Error("Detector2XYZ", "Invalid sector number %d (>=%d) in ring %c",
144 sector, GetNSectors(), fId);
145 return;
4347b38f 146 }
1a1fdef7 147 if (strip >= GetNStrips()) {
148 Error("Detector2XYZ", "Invalid strip number %d (>=%d)",
149 strip, GetNStrips(), fId);
150 return;
4347b38f 151 }
1a1fdef7 152 Double_t phi = Float_t(sector + .5) / GetNSectors() * 2 * TMath::Pi();
153 Double_t r = Float_t(strip + .5) / GetNStrips() * (fHighR - fLowR) + fLowR;
154 x = r * TMath::Cos(phi);
155 y = r * TMath::Sin(phi);
156 if (((sector / 2) % 2) == 1)
157 z += TMath::Sign(fModuleSpacing, z);
4347b38f 158}
159
54e415a8 160//____________________________________________________________________
161Bool_t
162AliFMDRing::XYZ2Detector(Double_t x,
163 Double_t y,
164 Double_t z,
165 UShort_t& sector,
166 UShort_t& strip) const
167{
088f8e79 168 // Translate global coordinates (x,y,z) to detector coordinates
169 // (this,sector,strip)
54e415a8 170 sector = strip = 0;
171 Double_t r = TMath::Sqrt(x * x + y * y);
172 Int_t str = Int_t((r - fMinR) / GetPitch());
173 if (str < 0 || str >= GetNStrips()) return kFALSE;
174
175 Double_t phi = TMath::ATan2(y, x) * 180. / TMath::Pi();
176 if (phi < 0) phi = 360. + phi;
177 Int_t sec = Int_t(phi / fTheta);
178 if (sec < 0 || sec >= GetNSectors()) return kFALSE;
179 if ((sec / 2) % 2 == 1) {
180 if (TMath::Abs(z - TMath::Sign(fModuleSpacing, z)) >= 0.01)
181 return kFALSE;
182 }
183 else if (TMath::Abs(z) >= 0.01) return kFALSE;
184
185 strip = str;
186 sector = sec;
187 return kTRUE;
188}
189
190
4347b38f 191//
192// EOF
193//