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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 | **************************************************************************/ | |
4ae5bbc4 | 15 | |
88cb7938 | 16 | /* $Id$ */ |
b0f5e3fc | 17 | |
4ae5bbc4 | 18 | #include <Riostream.h> |
55d2c544 | 19 | #include <TMath.h> |
b0f5e3fc | 20 | #include "AliITSsegmentationSSD.h" |
55d2c544 | 21 | |
22 | ////////////////////////////////////////////////////// | |
23 | // Segmentation class for // | |
24 | // silicon strips // | |
25 | // // | |
26 | ////////////////////////////////////////////////////// | |
27 | const Float_t AliITSsegmentationSSD::fgkDxDefault = 72960.; | |
28 | const Float_t AliITSsegmentationSSD::fgkDzDefault = 40000.; | |
29 | const Float_t AliITSsegmentationSSD::fgkDyDefault = 300.; | |
30 | const Float_t AliITSsegmentationSSD::fgkPitchDefault = 95.; | |
31 | const Int_t AliITSsegmentationSSD::fgkNstripsDefault = 768; | |
fd61217e | 32 | |
b0f5e3fc | 33 | ClassImp(AliITSsegmentationSSD) |
55d2c544 | 34 | AliITSsegmentationSSD::AliITSsegmentationSSD(): AliITSsegmentation(){ |
179578b2 | 35 | // default constructor |
b0f5e3fc | 36 | } |
179578b2 | 37 | //---------------------------------------------------------------------- |
b0f5e3fc | 38 | AliITSsegmentationSSD::AliITSsegmentationSSD(AliITSgeom *geom){ |
179578b2 | 39 | // constuctor |
40 | fGeom = geom; | |
41 | fCorr = 0; | |
55d2c544 | 42 | SetDetSize(fgkDxDefault,fgkDzDefault,fgkDyDefault); |
43 | SetPadSize(fgkPitchDefault,0.); | |
44 | SetNPads(fgkNstripsDefault,0); | |
179578b2 | 45 | SetAngles(); |
46 | fLayer = 0; | |
b0f5e3fc | 47 | } |
55d2c544 | 48 | |
49 | //______________________________________________________________________ | |
50 | void AliITSsegmentationSSD::Copy(TObject &obj) const { | |
51 | // protected method. copy this to obj | |
52 | AliITSsegmentation::Copy(obj); | |
53 | ((AliITSsegmentationSSD& ) obj).Clear(); | |
54 | ((AliITSsegmentationSSD& ) obj).fNstrips = fNstrips; | |
55 | ((AliITSsegmentationSSD& ) obj).fStereoP = fStereoP; | |
56 | ((AliITSsegmentationSSD& ) obj).fStereoN = fStereoN; | |
57 | ((AliITSsegmentationSSD& ) obj).fStereoPl5 = fStereoPl5; | |
58 | ((AliITSsegmentationSSD& ) obj).fStereoNl5 = fStereoNl5; | |
59 | ((AliITSsegmentationSSD& ) obj).fStereoPl6 = fStereoPl6; | |
60 | ((AliITSsegmentationSSD& ) obj).fStereoNl6 = fStereoNl6; | |
61 | ((AliITSsegmentationSSD& ) obj).fLayer = fLayer; | |
62 | ((AliITSsegmentationSSD& ) obj).fPitch = fPitch; | |
63 | ((AliITSsegmentationSSD& ) obj).fLayer = fLayer; | |
64 | ||
65 | } | |
66 | ||
179578b2 | 67 | //______________________________________________________________________ |
68 | AliITSsegmentationSSD& AliITSsegmentationSSD::operator=( | |
55d2c544 | 69 | const AliITSsegmentationSSD &source){ |
0315d466 | 70 | // Operator = |
55d2c544 | 71 | if(this != &source){ |
72 | source.Copy(*this); | |
73 | } | |
74 | return *this; | |
b0f5e3fc | 75 | } |
179578b2 | 76 | //______________________________________________________________________ |
55d2c544 | 77 | AliITSsegmentationSSD::AliITSsegmentationSSD(const AliITSsegmentationSSD &source): |
ac74f489 | 78 | AliITSsegmentation(source){ |
179578b2 | 79 | // copy constructor |
55d2c544 | 80 | source.Copy(*this); |
b0f5e3fc | 81 | } |
179578b2 | 82 | //---------------------------------------------------------------------- |
b0f5e3fc | 83 | void AliITSsegmentationSSD::Init(){ |
179578b2 | 84 | // standard initalizer |
b0f5e3fc | 85 | |
55d2c544 | 86 | SetPadSize(fgkPitchDefault,0.); |
87 | SetNPads(fgkNstripsDefault,0); | |
b0f5e3fc | 88 | SetAngles(); |
179578b2 | 89 | } |
90 | //---------------------------------------------------------------------- | |
55d2c544 | 91 | void AliITSsegmentationSSD::Angles(Float_t &aP,Float_t &aN) const{ |
92 | // P and N side stereo angles | |
179578b2 | 93 | if (fLayer == 5){ |
94 | aP = fStereoPl5; | |
95 | aN = fStereoNl5; | |
96 | } // end if | |
97 | if (fLayer == 6){ | |
98 | aP = fStereoPl6; | |
99 | aN = fStereoNl6; | |
100 | } // end if | |
0315d466 | 101 | } |
179578b2 | 102 | //---------------------------------------------------------------------- |
103 | void AliITSsegmentationSSD::SetLayer(Int_t l){ | |
55d2c544 | 104 | //set fLayer data member (only 5 or 6 are allowed) |
179578b2 | 105 | if (l==5) fLayer =5; |
106 | if (l==6) fLayer =6; | |
55d2c544 | 107 | if((l!=5) && (l!=6))Error("SetLayer","Layer can be 5 or 6, not %d",l); |
179578b2 | 108 | } |
109 | //---------------------------------------------------------------------- | |
55d2c544 | 110 | void AliITSsegmentationSSD::GetPadTxz(Float_t &x,Float_t &z) const{ |
179578b2 | 111 | // returns P and N sided strip numbers for a given location. |
112 | // Transformation from microns detector center local coordinates | |
113 | // to detector P and N side strip numbers.. | |
114 | /* _- Z | |
115 | + angle / ^ | |
116 | fNstrips v | N-Side ...0 | |
117 | \-------/------------|-----------\--------\ | |
118 | |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\| | |
119 | |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\| | |
120 | |00\\/////////////...|..\\\\\\\\\\\\\\\\\\| | |
121 | X <--|000/////////////... |...\\\\\\\\\\\\\\\\\| | |
122 | |00/////////////... | ...\\\\\\\\\\\\\\\\| | |
123 | |0/////////////... | ...\\\\\\\\\\\\\\\| | |
124 | |//////////////... | ...\\\\\\\\\\\\\\\| | |
125 | /-----\--------------|--------------------/ | |
126 | fNstrips-1 P-Side ...0 | |
127 | |0\ | |
128 | |00\ | |
129 | Dead region: |000/ | |
130 | |00/ | |
131 | |0/ | |
132 | // expects x, z in microns | |
133 | */ | |
55d2c544 | 134 | Float_t stereoP, stereoN; |
135 | Angles(stereoP,stereoN); | |
136 | Float_t tanP = TMath::Tan(stereoP); | |
137 | Float_t tanN = TMath::Tan(-stereoN); | |
179578b2 | 138 | Float_t x1 = x; |
139 | Float_t z1 = z; | |
140 | x1 += fDx/2; | |
141 | z1 += fDz/2; | |
142 | x = (x1 - z1*tanP)/fPitch; | |
143 | z = (x1 - tanN*(z1 - fDz))/fPitch; | |
144 | } | |
145 | //---------------------------------------------------------------------- | |
55d2c544 | 146 | void AliITSsegmentationSSD::GetPadIxz(Float_t x,Float_t z,Int_t &iP,Int_t &iN) const { |
0315d466 | 147 | // returns P and N sided strip numbers for a given location. |
179578b2 | 148 | /* _- Z |
149 | + angle / ^ | |
150 | fNstrips v | N-Side ...0 | |
151 | \-------/------------|-----------\--------\ | |
152 | |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\| | |
153 | |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\| | |
154 | |00\\/////////////...|..\\\\\\\\\\\\\\\\\\| | |
155 | X <--|000/////////////... |...\\\\\\\\\\\\\\\\\| | |
156 | |00/////////////... | ...\\\\\\\\\\\\\\\\| | |
157 | |0/////////////... | ...\\\\\\\\\\\\\\\| | |
158 | |//////////////... | ...\\\\\\\\\\\\\\\| | |
159 | /-----\--------------|--------------------/ | |
160 | fNstrips-1 P-Side ...0 | |
161 | |0\ | |
162 | |00\ | |
163 | Dead region: |000/ | |
164 | |00/ | |
165 | |0/ | |
b0f5e3fc | 166 | |
167 | // expects x, z in microns | |
179578b2 | 168 | */ |
c1c63494 | 169 | |
55d2c544 | 170 | Float_t stereoP, stereoN; |
171 | Angles(stereoP,stereoN); | |
172 | Float_t tanP=TMath::Tan(stereoP); | |
173 | Float_t tanN=TMath::Tan(stereoN); | |
0315d466 | 174 | Float_t x1=x,z1=z; |
175 | x1 += fDx/2; | |
176 | z1 += fDz/2; | |
177 | Float_t ldX = x1 - z1*tanP; // distance from left-down edge | |
178 | iP = (Int_t)(ldX/fPitch); | |
b0f5e3fc | 179 | iP = (iP<0)? -1: iP; |
180 | iP = (iP>fNstrips)? -1: iP; | |
0315d466 | 181 | |
182 | ldX = x1 - tanN*(fDz - z1); | |
183 | iN = (Int_t)(ldX/fPitch); | |
b0f5e3fc | 184 | iN = (iN<0)? -1: iN; |
185 | iN = (iN>fNstrips)? -1: iN; | |
0315d466 | 186 | |
b0f5e3fc | 187 | } |
0315d466 | 188 | //------------------------------------------------------- |
55d2c544 | 189 | void AliITSsegmentationSSD::GetPadCxz(Int_t iP,Int_t iN,Float_t &x,Float_t &z) const { |
179578b2 | 190 | // actually this is the GetCrossing(Float_t &,Float_t &) |
0315d466 | 191 | // returns local x, z in microns ! |
b0f5e3fc | 192 | |
55d2c544 | 193 | Float_t lDx = fDx; // detector size in x direction, microns |
194 | Float_t lDz = fDz; // detector size in z direction, microns | |
179578b2 | 195 | Float_t xP; // x coordinate in the P side from the first P strip |
196 | Float_t xN; // x coordinate in the N side from the first N strip | |
55d2c544 | 197 | Float_t stereoP, stereoN; |
198 | Angles(stereoP,stereoN); | |
199 | Float_t kP=TMath::Tan(stereoP); | |
200 | Float_t kN=TMath::Tan(stereoN); | |
b0f5e3fc | 201 | |
0315d466 | 202 | xP=iP*fPitch; |
203 | xN=iN*fPitch; | |
55d2c544 | 204 | x = xP + kP*(lDz*kN-xP+xN)/(kP+kN); |
205 | z = (lDz*kN-xP+xN)/(kP+kN); | |
206 | x -= lDx/2; | |
207 | z -= lDz/2; | |
66da7685 | 208 | //if(TMath::Abs(z) > Dz/2) cout<<"Warning, wrong z local ="<<z<<endl; |
0315d466 | 209 | // Check that zL is inside the detector for the |
210 | // correspondent xP and xN coordinates | |
b0f5e3fc | 211 | |
212 | return; | |
213 | } | |
179578b2 | 214 | //______________________________________________________________________ |
215 | void AliITSsegmentationSSD::LocalToDet(Float_t x,Float_t z, | |
55d2c544 | 216 | Int_t &iP,Int_t &iN) const { |
179578b2 | 217 | // Transformation from Geant cm detector center local coordinates |
218 | // to detector P and N side strip numbers.. | |
219 | /* _- Z | |
220 | + angle / ^ | |
221 | fNstrips v | N-Side ...0 | |
222 | \-------/------------|-----------\--------\ | |
223 | |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\| | |
224 | |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\| | |
225 | |00\\/////////////...|..\\\\\\\\\\\\\\\\\\| | |
226 | X <--|000/////////////... |...\\\\\\\\\\\\\\\\\| | |
227 | |00/////////////... | ...\\\\\\\\\\\\\\\\| | |
228 | |0/////////////... | ...\\\\\\\\\\\\\\\| | |
229 | |//////////////... | ...\\\\\\\\\\\\\\\| | |
230 | /-----\--------------|--------------------/ | |
231 | fNstrips-1 P-Side ...0 | |
232 | |0\ | |
233 | |00\ | |
234 | Dead region: |000/ | |
235 | |00/ | |
236 | |0/ | |
237 | */ | |
238 | const Double_t kconst = 1.0E-04; // convert microns to cm. | |
239 | ||
240 | x /= kconst; // convert to microns | |
241 | z /= kconst; // convert to microns | |
242 | this->GetPadTxz(x,z); | |
5752a110 | 243 | |
179578b2 | 244 | // first for P side |
245 | iP = (Int_t) x; | |
246 | if(iP<0 || iP>=fNstrips) iP=-1; // strip number must be in range. | |
247 | // Now for N side) | |
248 | iN = (Int_t) z; | |
249 | if(iN<0 || iN>=fNstrips) iN=-1; // strip number must be in range. | |
250 | return; | |
251 | } | |
252 | //---------------------------------------------------------------------- | |
253 | void AliITSsegmentationSSD::DetToLocal(Int_t ix,Int_t iPN, | |
55d2c544 | 254 | Float_t &x,Float_t &z) const{ |
179578b2 | 255 | // Transformation from detector segmentation/cell coordiantes starting |
256 | // from 0. iPN=0 for P side and 1 for N side strip. Returned is z=0.0 | |
257 | // and the corresponding x value.. | |
258 | /* _- Z | |
259 | + angle / ^ | |
260 | fNstrips v | N-Side ...0 | |
261 | \-------/------------|-----------\--------\ | |
262 | |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\| | |
263 | |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\| | |
264 | |00\\/////////////...|..\\\\\\\\\\\\\\\\\\| | |
265 | X <--|000/////////////... |...\\\\\\\\\\\\\\\\\| | |
266 | |00/////////////... | ...\\\\\\\\\\\\\\\\| | |
267 | |0/////////////... | ...\\\\\\\\\\\\\\\| | |
268 | |//////////////... | ...\\\\\\\\\\\\\\\| | |
269 | /-----\--------------|--------------------/ | |
270 | fNstrips-1 P-Side ...0 | |
271 | |0\ | |
272 | |00\ | |
273 | Dead region: |000/ | |
274 | |00/ | |
275 | |0/ | |
276 | */ | |
277 | // for strips p-side | |
278 | // x = a + b + z*tan(fStereoP); a = Dpx(iP)*(iP+0.5)-dx; b = dz*th; | |
279 | // for strips n-side | |
280 | // x = a + b + z*tan(fStereoP); a = Dpx(iN)*(iN+0.5)-dx; b = -dz*th; | |
281 | const Double_t kconst = 1.0E-04; // convert microns to cm. | |
282 | Float_t flag=kconst*Dx(); // error value | |
283 | Double_t th=0.0,dx,dz,i,a,b=0.0,xb[4],zb[4]; | |
55d2c544 | 284 | Float_t stereoP, stereoN; |
285 | Angles(stereoP,stereoN); | |
5752a110 | 286 | |
179578b2 | 287 | z = 0.0; // Strip center in z. |
288 | if(iPN<0 || iPN>1){// if error return full detector size in x. | |
289 | x = z = flag; | |
290 | return; | |
291 | } // end if | |
292 | if(ix<0 || ix>=fNstrips) { // if error return full detector size in x. | |
293 | x = z = flag; | |
294 | return; | |
295 | } // end if | |
296 | i = (Double_t) ix; // convert to double | |
297 | dx = 0.5*kconst*Dx(); // half distance in x in cm | |
298 | dz = 0.5*kconst*Dz(); // half distance in z in cm | |
299 | a = kconst*Dpx(ix)*(i+0.5)-dx; // Min x value. | |
300 | if(iPN==0){ //P-side angle defined backwards. | |
55d2c544 | 301 | th = TMath::Tan(stereoP); |
179578b2 | 302 | b = dz*th; |
303 | }else if(iPN==1){ // N-side | |
55d2c544 | 304 | th = TMath::Tan(-stereoN); |
179578b2 | 305 | b = -dz*th; |
306 | } // end if | |
307 | // compute average/center position of the strip. | |
308 | xb[0] = +dx; if(th!=0.0) zb[0] = (+dx-a-b)/th; else zb[0] = 0.0; | |
309 | xb[1] = -dx; if(th!=0.0) zb[1] = (-dx-a-b)/th; else zb[1] = 0.0; | |
310 | xb[2] = a+b+dz*th; zb[2] = +dz; | |
311 | xb[3] = a+b-dz*th; zb[3] = -dz; | |
312 | x = 0.0; z = 0.0; | |
313 | for(Int_t j=0;j<4;j++){ | |
314 | if(xb[j]>=-dx && xb[j]<=dx && zb[j]>=-dz && zb[j]<=dz){ | |
315 | x += xb[j]; | |
316 | z += zb[j]; | |
317 | } // end if | |
318 | } // end for | |
319 | x *= 0.5; | |
320 | z *= 0.5; | |
321 | return; | |
322 | } | |
323 | //---------------------------------------------------------------------- | |
324 | Bool_t AliITSsegmentationSSD::GetCrossing(Int_t iP,Int_t iN, | |
325 | Float_t &x,Float_t &z, | |
326 | Float_t c[2][2]){ | |
327 | // Given one P side strip and one N side strip, Returns kTRUE if they | |
328 | // cross each other and the location of the two crossing strips and | |
329 | // their correxlation matrix c[2][2]. | |
330 | /* _- Z | |
331 | + angle / ^ | |
332 | fNstrips v | N-Side ...0 | |
333 | \-------/------------|-----------\--------\ | |
334 | |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\| | |
335 | |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\| | |
336 | |00\\/////////////...|..\\\\\\\\\\\\\\\\\\| | |
337 | X <--|000/////////////... |...\\\\\\\\\\\\\\\\\| | |
338 | |00/////////////... | ...\\\\\\\\\\\\\\\\| | |
339 | |0/////////////... | ...\\\\\\\\\\\\\\\| | |
340 | |//////////////... | ...\\\\\\\\\\\\\\\| | |
341 | /-----\--------------|--------------------/ | |
342 | fNstrips-1 P-Side ...0 | |
343 | |0\ | |
344 | |00\ | |
345 | Dead region: |000/ | |
346 | |00/ | |
347 | |0/ | |
348 | c[2][2] is defined as follows | |
349 | /c[0][0] c[0][1]\ /delta iP\ = /delta x\ | |
350 | \c[1][0] c[1][1]/ \delta iN/ = \delta z/ | |
351 | */ | |
352 | const Double_t kconst = 1.0E-04; // convert microns to cm. | |
353 | Double_t thp,thn,th,dx,dz,p,ip,in; | |
55d2c544 | 354 | Float_t stereoP, stereoN; |
355 | Angles(stereoP,stereoN); | |
179578b2 | 356 | |
55d2c544 | 357 | thp = TMath::Tan(stereoP); |
358 | thn = TMath::Tan(-stereoN); | |
179578b2 | 359 | th = thp-thn; |
360 | if(th==0.0) { // parall strips then never cross. | |
361 | x = 0.0; | |
362 | z = 0.0; | |
363 | c[0][0] = c[1][0] = c[0][1] = c[1][1] = 0.0; | |
364 | return kFALSE; | |
365 | } // end if | |
366 | // The strips must cross some place in space. | |
367 | ip = (Double_t) iP; // convert to double now for speed | |
368 | in = (Double_t) iN; // convert to double now for speed | |
369 | dx = 0.5*kconst*Dx(); // half distance in x in cm | |
370 | dz = 0.5*kconst*Dz(); // half distance in z in cm | |
371 | p = kconst*Dpx(iP); // Get strip spacing/pitch now | |
372 | x = 0.5*p+dx + (p*(in*thp-ip*thn)-2.0*dz*thp*thn)/th; | |
373 | z =(p*(in-ip)-dz*(thp+thn))/th; | |
374 | // compute correlations. | |
375 | c[0][0] = -thn*p/th; // dx/diP | |
376 | c[1][1] = p/th; // dz/diN | |
377 | c[0][1] = p*thp/th; // dx/diN | |
378 | c[1][0] = -p/th; // dz/diP | |
379 | if(x<-dx || x>dx || z<-dz || z>dz) return kFALSE; // crossing is outside | |
380 | // of the detector so | |
381 | // these strips don't | |
382 | // cross. | |
383 | return kTRUE; | |
384 | } | |
55d2c544 | 385 | |
386 | //---------------------------------------------------------------------- | |
387 | void AliITSsegmentationSSD::PrintDefaultParameters() const { | |
388 | // Print default values for parameters. | |
389 | // Values specified as static const data members are shown | |
390 | ||
391 | cout<<"fgkDxDefault = "<<fgkDxDefault<<endl; | |
392 | cout<<"fgkDzDefault = "<<fgkDzDefault<<endl; | |
393 | cout<<"fgkDyDefault = "<<fgkDyDefault<<endl; | |
394 | cout<<"fgkPitchDefault = "<<fgkPitchDefault<<endl; | |
395 | cout<<"fgkNstripsDefault = "<<fgkNstripsDefault<<endl; | |
396 | } |