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Added EDEFINE with the flags from Geant4
[u/mrichter/AliRoot.git] / ITS / AliITSsegmentationSSD.cxx
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b0f5e3fc 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
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 **************************************************************************/
179578b2 15/*
16$Log$
9e1a0ddb 17Revision 1.14 2001/05/14 06:21:49 barbera
18Some unuseful printout commented
19
66da7685 20Revision 1.13 2001/05/14 05:44:11 barbera
21Version 1.11 reput in place to avoid problem with reconstruction
22
179578b2 23Revision 1.11 2001/05/03 16:12:37 nilsen
24Fixed up LocalToDet, DetToLocal, GetCrossing, GetPadTxz to work with different
25angles in layer 5 and 6.
26
27Revision 1.10 2001/05/01 22:42:22 nilsen
28Update of SSD simulation and reconstruction code by Boris and Enrico.
29
30Revision 1.9 2001/04/27 14:16:50 nilsen
31Remove dead and/or unused code and printout lines. i.e. cleaned it up a bit.
32
33*/
b0f5e3fc 34
35#include <TMath.h>
1ca7869b 36#include <TF1.h>
fd61217e 37#include <iostream.h>
b0f5e3fc 38#include "AliITSsegmentationSSD.h"
39#include "AliITSgeom.h"
9e1a0ddb 40#include "AliRun.h"
41#include "AliModule.h"
fd61217e 42
b0f5e3fc 43ClassImp(AliITSsegmentationSSD)
44AliITSsegmentationSSD::AliITSsegmentationSSD(){
179578b2 45 // default constructor
46 fGeom = 0;
47 fCorr = 0;
48 fLayer = 0;
b0f5e3fc 49}
179578b2 50//----------------------------------------------------------------------
b0f5e3fc 51AliITSsegmentationSSD::AliITSsegmentationSSD(AliITSgeom *geom){
179578b2 52 // constuctor
53 fGeom = geom;
54 fCorr = 0;
55 SetDetSize();
56 SetPadSize();
57 SetNPads();
58 SetAngles();
59 fLayer = 0;
b0f5e3fc 60}
179578b2 61//______________________________________________________________________
62AliITSsegmentationSSD& AliITSsegmentationSSD::operator=(
63 AliITSsegmentationSSD &source){
0315d466 64// Operator =
179578b2 65 if(this==&source) return *this;
66 this->fNstrips = source.fNstrips;
67 this->fStereoP = source.fStereoP;
68 this->fStereoN = source.fStereoN;
69 this->fStereoPl5 = source.fStereoPl5;
70 this->fStereoNl5 = source.fStereoNl5;
71 this->fStereoPl6 = source.fStereoPl6;
72 this->fStereoNl6 = source.fStereoNl6;
73 this->fLayer = source.fLayer;
74 this->fPitch = source.fPitch;
75 this->fDz = source.fDz;
76 this->fDx = source.fDx;
77 this->fDy = source.fDy;
78 this->fLayer = source.fLayer;
79 this->fGeom = source.fGeom; // copy only the pointer
80 this->fCorr = new TF1(*(source.fCorr)); // make a proper copy
81 return *this;
b0f5e3fc 82}
179578b2 83//______________________________________________________________________
b0f5e3fc 84AliITSsegmentationSSD::AliITSsegmentationSSD(AliITSsegmentationSSD &source){
179578b2 85 // copy constructor
86 *this = source;
b0f5e3fc 87}
179578b2 88//----------------------------------------------------------------------
b0f5e3fc 89void AliITSsegmentationSSD::Init(){
179578b2 90 // standard initalizer
b0f5e3fc 91
e8189707 92 SetPadSize();
93 SetNPads();
b0f5e3fc 94 SetAngles();
179578b2 95}
96//----------------------------------------------------------------------
97void AliITSsegmentationSSD::Angles(Float_t &aP,Float_t &aN){
0315d466 98
179578b2 99 if (fLayer == 5){
100 aP = fStereoPl5;
101 aN = fStereoNl5;
102 } // end if
103 if (fLayer == 6){
104 aP = fStereoPl6;
105 aN = fStereoNl6;
106 } // end if
0315d466 107}
179578b2 108//----------------------------------------------------------------------
109void AliITSsegmentationSSD::SetLayer(Int_t l){
0315d466 110
179578b2 111 if (l==5) fLayer =5;
112 if (l==6) fLayer =6;
113}
114//----------------------------------------------------------------------
115void AliITSsegmentationSSD::GetPadTxz(Float_t &x,Float_t &z){
116 // returns P and N sided strip numbers for a given location.
117 // Transformation from microns detector center local coordinates
118 // to detector P and N side strip numbers..
119 /* _- Z
120 + angle / ^
121 fNstrips v | N-Side ...0
122 \-------/------------|-----------\--------\
123 |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\|
124 |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\|
125 |00\\/////////////...|..\\\\\\\\\\\\\\\\\\|
126 X <--|000/////////////... |...\\\\\\\\\\\\\\\\\|
127 |00/////////////... | ...\\\\\\\\\\\\\\\\|
128 |0/////////////... | ...\\\\\\\\\\\\\\\|
129 |//////////////... | ...\\\\\\\\\\\\\\\|
130 /-----\--------------|--------------------/
131 fNstrips-1 P-Side ...0
132 |0\
133 |00\
134 Dead region: |000/
135 |00/
136 |0/
137 // expects x, z in microns
138 */
139 Float_t StereoP, StereoN;
140 Angles(StereoP,StereoN);
141 Float_t tanP = TMath::Tan(StereoP);
142 Float_t tanN = TMath::Tan(-StereoN);
143 Float_t x1 = x;
144 Float_t z1 = z;
145 x1 += fDx/2;
146 z1 += fDz/2;
147 x = (x1 - z1*tanP)/fPitch;
148 z = (x1 - tanN*(z1 - fDz))/fPitch;
149}
150//----------------------------------------------------------------------
151void AliITSsegmentationSSD::GetPadIxz(Float_t x,Float_t z,Int_t &iP,Int_t &iN){
0315d466 152 // returns P and N sided strip numbers for a given location.
179578b2 153 /* _- Z
154 + angle / ^
155 fNstrips v | N-Side ...0
156 \-------/------------|-----------\--------\
157 |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\|
158 |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\|
159 |00\\/////////////...|..\\\\\\\\\\\\\\\\\\|
160 X <--|000/////////////... |...\\\\\\\\\\\\\\\\\|
161 |00/////////////... | ...\\\\\\\\\\\\\\\\|
162 |0/////////////... | ...\\\\\\\\\\\\\\\|
163 |//////////////... | ...\\\\\\\\\\\\\\\|
164 /-----\--------------|--------------------/
165 fNstrips-1 P-Side ...0
166 |0\
167 |00\
168 Dead region: |000/
169 |00/
170 |0/
b0f5e3fc 171
172 // expects x, z in microns
179578b2 173 */
c1c63494 174
0315d466 175 Float_t StereoP, StereoN;
176 Angles(StereoP,StereoN);
177 Float_t tanP=TMath::Tan(StereoP);
178 Float_t tanN=TMath::Tan(StereoN);
179 Float_t x1=x,z1=z;
180 x1 += fDx/2;
181 z1 += fDz/2;
182 Float_t ldX = x1 - z1*tanP; // distance from left-down edge
183 iP = (Int_t)(ldX/fPitch);
b0f5e3fc 184 iP = (iP<0)? -1: iP;
185 iP = (iP>fNstrips)? -1: iP;
0315d466 186
187 ldX = x1 - tanN*(fDz - z1);
188 iN = (Int_t)(ldX/fPitch);
b0f5e3fc 189 iN = (iN<0)? -1: iN;
190 iN = (iN>fNstrips)? -1: iN;
0315d466 191
b0f5e3fc 192}
0315d466 193//-------------------------------------------------------
179578b2 194void AliITSsegmentationSSD::GetPadCxz(Int_t iP,Int_t iN,Float_t &x,Float_t &z){
195 // actually this is the GetCrossing(Float_t &,Float_t &)
0315d466 196 // returns local x, z in microns !
b0f5e3fc 197
179578b2 198 Float_t Dx = fDx; // detector size in x direction, microns
199 Float_t Dz = fDz; // detector size in z direction, microns
200 Float_t xP; // x coordinate in the P side from the first P strip
201 Float_t xN; // x coordinate in the N side from the first N strip
202 Float_t StereoP, StereoN;
203 Angles(StereoP,StereoN);
204 Float_t kP=TMath::Tan(StereoP);
205 Float_t kN=TMath::Tan(StereoN);
b0f5e3fc 206
0315d466 207 xP=iP*fPitch;
208 xN=iN*fPitch;
209 x = xP + kP*(Dz*kN-xP+xN)/(kP+kN);
210 z = (Dz*kN-xP+xN)/(kP+kN);
211 x -= Dx/2;
212 z -= Dz/2;
66da7685 213 //if(TMath::Abs(z) > Dz/2) cout<<"Warning, wrong z local ="<<z<<endl;
0315d466 214 // Check that zL is inside the detector for the
215 // correspondent xP and xN coordinates
b0f5e3fc 216
217 return;
218}
179578b2 219//______________________________________________________________________
220void AliITSsegmentationSSD::LocalToDet(Float_t x,Float_t z,
221 Int_t &iP,Int_t &iN){
222 // Transformation from Geant cm detector center local coordinates
223 // to detector P and N side strip numbers..
224 /* _- Z
225 + angle / ^
226 fNstrips v | N-Side ...0
227 \-------/------------|-----------\--------\
228 |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\|
229 |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\|
230 |00\\/////////////...|..\\\\\\\\\\\\\\\\\\|
231 X <--|000/////////////... |...\\\\\\\\\\\\\\\\\|
232 |00/////////////... | ...\\\\\\\\\\\\\\\\|
233 |0/////////////... | ...\\\\\\\\\\\\\\\|
234 |//////////////... | ...\\\\\\\\\\\\\\\|
235 /-----\--------------|--------------------/
236 fNstrips-1 P-Side ...0
237 |0\
238 |00\
239 Dead region: |000/
240 |00/
241 |0/
242 */
243 const Double_t kconst = 1.0E-04; // convert microns to cm.
244
245 x /= kconst; // convert to microns
246 z /= kconst; // convert to microns
247 this->GetPadTxz(x,z);
5752a110 248
179578b2 249 // first for P side
250 iP = (Int_t) x;
251 if(iP<0 || iP>=fNstrips) iP=-1; // strip number must be in range.
252 // Now for N side)
253 iN = (Int_t) z;
254 if(iN<0 || iN>=fNstrips) iN=-1; // strip number must be in range.
255 return;
256}
257//----------------------------------------------------------------------
258void AliITSsegmentationSSD::DetToLocal(Int_t ix,Int_t iPN,
259 Float_t &x,Float_t &z){
260 // Transformation from detector segmentation/cell coordiantes starting
261 // from 0. iPN=0 for P side and 1 for N side strip. Returned is z=0.0
262 // and the corresponding x value..
263 /* _- Z
264 + angle / ^
265 fNstrips v | N-Side ...0
266 \-------/------------|-----------\--------\
267 |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\|
268 |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\|
269 |00\\/////////////...|..\\\\\\\\\\\\\\\\\\|
270 X <--|000/////////////... |...\\\\\\\\\\\\\\\\\|
271 |00/////////////... | ...\\\\\\\\\\\\\\\\|
272 |0/////////////... | ...\\\\\\\\\\\\\\\|
273 |//////////////... | ...\\\\\\\\\\\\\\\|
274 /-----\--------------|--------------------/
275 fNstrips-1 P-Side ...0
276 |0\
277 |00\
278 Dead region: |000/
279 |00/
280 |0/
281 */
282 // for strips p-side
283 // x = a + b + z*tan(fStereoP); a = Dpx(iP)*(iP+0.5)-dx; b = dz*th;
284 // for strips n-side
285 // x = a + b + z*tan(fStereoP); a = Dpx(iN)*(iN+0.5)-dx; b = -dz*th;
286 const Double_t kconst = 1.0E-04; // convert microns to cm.
287 Float_t flag=kconst*Dx(); // error value
288 Double_t th=0.0,dx,dz,i,a,b=0.0,xb[4],zb[4];
289 Float_t StereoP, StereoN;
290 Angles(StereoP,StereoN);
5752a110 291
179578b2 292 z = 0.0; // Strip center in z.
293 if(iPN<0 || iPN>1){// if error return full detector size in x.
294 x = z = flag;
295 return;
296 } // end if
297 if(ix<0 || ix>=fNstrips) { // if error return full detector size in x.
298 x = z = flag;
299 return;
300 } // end if
301 i = (Double_t) ix; // convert to double
302 dx = 0.5*kconst*Dx(); // half distance in x in cm
303 dz = 0.5*kconst*Dz(); // half distance in z in cm
304 a = kconst*Dpx(ix)*(i+0.5)-dx; // Min x value.
305 if(iPN==0){ //P-side angle defined backwards.
306 th = TMath::Tan(StereoP);
307 b = dz*th;
308 }else if(iPN==1){ // N-side
309 th = TMath::Tan(-StereoN);
310 b = -dz*th;
311 } // end if
312 // compute average/center position of the strip.
313 xb[0] = +dx; if(th!=0.0) zb[0] = (+dx-a-b)/th; else zb[0] = 0.0;
314 xb[1] = -dx; if(th!=0.0) zb[1] = (-dx-a-b)/th; else zb[1] = 0.0;
315 xb[2] = a+b+dz*th; zb[2] = +dz;
316 xb[3] = a+b-dz*th; zb[3] = -dz;
317 x = 0.0; z = 0.0;
318 for(Int_t j=0;j<4;j++){
319 if(xb[j]>=-dx && xb[j]<=dx && zb[j]>=-dz && zb[j]<=dz){
320 x += xb[j];
321 z += zb[j];
322 } // end if
323 } // end for
324 x *= 0.5;
325 z *= 0.5;
326 return;
327}
328//----------------------------------------------------------------------
329Bool_t AliITSsegmentationSSD::GetCrossing(Int_t iP,Int_t iN,
330 Float_t &x,Float_t &z,
331 Float_t c[2][2]){
332 // Given one P side strip and one N side strip, Returns kTRUE if they
333 // cross each other and the location of the two crossing strips and
334 // their correxlation matrix c[2][2].
335 /* _- Z
336 + angle / ^
337 fNstrips v | N-Side ...0
338 \-------/------------|-----------\--------\
339 |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\|
340 |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\|
341 |00\\/////////////...|..\\\\\\\\\\\\\\\\\\|
342 X <--|000/////////////... |...\\\\\\\\\\\\\\\\\|
343 |00/////////////... | ...\\\\\\\\\\\\\\\\|
344 |0/////////////... | ...\\\\\\\\\\\\\\\|
345 |//////////////... | ...\\\\\\\\\\\\\\\|
346 /-----\--------------|--------------------/
347 fNstrips-1 P-Side ...0
348 |0\
349 |00\
350 Dead region: |000/
351 |00/
352 |0/
353 c[2][2] is defined as follows
354 /c[0][0] c[0][1]\ /delta iP\ = /delta x\
355 \c[1][0] c[1][1]/ \delta iN/ = \delta z/
356 */
357 const Double_t kconst = 1.0E-04; // convert microns to cm.
358 Double_t thp,thn,th,dx,dz,p,ip,in;
359 Float_t StereoP, StereoN;
360 Angles(StereoP,StereoN);
361
362 thp = TMath::Tan(StereoP);
363 thn = TMath::Tan(-StereoN);
364 th = thp-thn;
365 if(th==0.0) { // parall strips then never cross.
366 x = 0.0;
367 z = 0.0;
368 c[0][0] = c[1][0] = c[0][1] = c[1][1] = 0.0;
369 return kFALSE;
370 } // end if
371 // The strips must cross some place in space.
372 ip = (Double_t) iP; // convert to double now for speed
373 in = (Double_t) iN; // convert to double now for speed
374 dx = 0.5*kconst*Dx(); // half distance in x in cm
375 dz = 0.5*kconst*Dz(); // half distance in z in cm
376 p = kconst*Dpx(iP); // Get strip spacing/pitch now
377 x = 0.5*p+dx + (p*(in*thp-ip*thn)-2.0*dz*thp*thn)/th;
378 z =(p*(in-ip)-dz*(thp+thn))/th;
379 // compute correlations.
380 c[0][0] = -thn*p/th; // dx/diP
381 c[1][1] = p/th; // dz/diN
382 c[0][1] = p*thp/th; // dx/diN
383 c[1][0] = -p/th; // dz/diP
384 if(x<-dx || x>dx || z<-dz || z>dz) return kFALSE; // crossing is outside
385 // of the detector so
386 // these strips don't
387 // cross.
388 return kTRUE;
389}