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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  *                                                                        *
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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
18
19 //-----------------------------------------------------------------------------
20 /// \class AliMUONTrackHitPattern
21 ///
22 /// This class propagates tracks to trigger chambers 
23 /// searching for matching trigger tracks and fired strips.
24 ///
25 /// To each track, a hit pattern for trigger chambers is set.
26 /// The hit pattern is a UShort_t with 8 bits used:
27 ///                                                                      <pre>
28 ///            1  1  0  1    1  1  0  1
29 ///           |           |            |
30 ///            ----------- ------------
31 /// chamber:  11 12 13 14 | 11 12 13 14
32 /// cathode:    bending   | non-bending
33 ///                                                                      </pre>
34 /// The main method is:
35 /// * ExecuteValidation
36 ///
37 ///  \author Diego Stocco
38 //-----------------------------------------------------------------------------
39
40
41 #include "AliMUONTrackHitPattern.h"
42
43 #include "AliMUONConstants.h"
44 #include "AliMUONVDigit.h"
45 #include "AliMUONDigitMaker.h"
46 #include "AliMUONDigitStoreV1.h"
47 #include "AliMUONGeometryTransformer.h"
48 #include "AliMUONLocalTrigger.h"
49 #include "AliMUONLocalTriggerBoard.h"
50 #include "AliMUONTrack.h"
51 #include "AliMUONTrackExtrap.h"
52 #include "AliMUONTrackParam.h"
53 #include "AliMUONVTrackStore.h"
54 #include "AliMUONVTriggerStore.h"
55 #include "AliMpPad.h"
56 #include "AliMpSegmentation.h"
57 #include "AliMpVSegmentation.h"
58 #include "AliMpDEManager.h"
59 #include "AliMUONReconstructor.h"
60 #include "AliMUONRecoParam.h"
61 #include "AliMUONTriggerTrack.h"
62 #include "AliMUONVTriggerTrackStore.h"
63
64 #include "AliMpConstants.h"
65
66 #include "AliMagF.h"
67 #include "AliLog.h"
68 #include "AliTracker.h"
69
70 #include <Riostream.h>
71 #include <TArrayS.h>
72 #include <TClonesArray.h>
73 #include <TMath.h>
74 #include <TMatrixD.h>
75 #include <TROOT.h>
76 #include <TDirectory.h>
77 #include <TFile.h>
78 #include <TSystem.h>
79
80 #include <cassert>
81
82 /// \cond CLASSIMP
83 ClassImp(AliMUONTrackHitPattern) // Class implementation in ROOT context
84 /// \endcond
85
86
87 //______________________________________________________________________________
88 AliMUONTrackHitPattern::AliMUONTrackHitPattern(const AliMUONGeometryTransformer& transformer,
89                                                const AliMUONDigitMaker& digitMaker)
90     : TObject(),
91       fTransformer(transformer),
92       fDigitMaker(digitMaker),
93       fDeltaZ(0.0),
94       fTrigCovariance(0x0),
95       fkMaxDistance(99999.)
96 {
97     /// Default constructor
98     InitMembers();
99
100     // Set magnetic field
101     const AliMagF* kField = AliTracker::GetFieldMap();
102     if (!kField) AliFatal("No field available");
103     AliMUONTrackExtrap::SetField(kField);
104 }
105
106
107 //______________________________________________________________________________
108 AliMUONTrackHitPattern::~AliMUONTrackHitPattern(void)
109 {
110   /// Destructor
111   delete fTrigCovariance;
112 }
113
114
115 //______________________________________________________________________________
116 void AliMUONTrackHitPattern::InitMembers()
117 {
118   //
119   /// Initialize data members
120   //
121   fDeltaZ = TMath::Abs(AliMUONConstants::DefaultChamberZ(12) - AliMUONConstants::DefaultChamberZ(10));
122
123   const Double_t kTrigNonBendReso = AliMUONConstants::TriggerNonBendingReso();
124   const Double_t kTrigBendReso = AliMUONConstants::TriggerBendingReso();
125   const Double_t kTrigSlopeBendReso = 1.414 * AliMUONConstants::TriggerBendingReso()/fDeltaZ;
126   const Double_t kTrigCovSlopeBend = - kTrigBendReso * kTrigBendReso / fDeltaZ;
127
128   // Covariance matrix 3x3 (X,Y,slopeY) for trigger tracks
129   fTrigCovariance = new TMatrixD(3,3);
130   fTrigCovariance->Zero();
131   (*fTrigCovariance)(0,0) = kTrigNonBendReso * kTrigNonBendReso;
132   (*fTrigCovariance)(1,1) = kTrigBendReso * kTrigBendReso;
133   (*fTrigCovariance)(2,2) = kTrigSlopeBendReso * kTrigSlopeBendReso;
134   (*fTrigCovariance)(1,2) = (*fTrigCovariance)(2,1) = kTrigCovSlopeBend;
135 }
136
137
138 //_____________________________________________________________________________
139 void AliMUONTrackHitPattern::CheckConstants() const
140 {
141 /// Check consistence of redefined constants 
142
143   assert(fgkNcathodes == AliMpConstants::NofCathodes());    
144   assert(fgkNchambers == AliMpConstants::NofTriggerChambers());    
145   assert(fgkNplanes == AliMpConstants::NofTriggerChambers() * fgkNcathodes);    
146 }
147
148
149 //______________________________________________________________________________
150 void AliMUONTrackHitPattern::ExecuteValidation(AliMUONVTrackStore& trackStore,
151                                                const AliMUONVTriggerTrackStore& triggerTrackStore,
152                                                const AliMUONVTriggerStore& triggerStore) const
153 {
154   //
155   /// Main method:
156   /// Loops on reco tracks, extrapolates them to trigger chambers
157   /// and searches for matching trigger tracks and digits
158   //
159
160   AliMUONDigitStoreV1 digitStore;
161   TriggerDigits(triggerStore,digitStore);
162
163
164   TIter itTrack(trackStore.CreateIterator());
165   AliMUONTrack* track;
166
167   const Int_t kFirstTrigCh = AliMUONConstants::NTrackingCh();
168
169   while ( ( track = static_cast<AliMUONTrack*>(itTrack()) ) )
170   { 
171     AliMUONTrackParam trackParam(*((AliMUONTrackParam*) (track->GetTrackParamAtCluster()->Last())));
172
173     ApplyMCSCorrections(trackParam);
174     AliMUONTrackExtrap::ExtrapToZCov(&trackParam, AliMUONConstants::DefaultChamberZ(kFirstTrigCh)); // extrap to 1st trigger chamber
175
176     AliMUONTriggerTrack *matchedTriggerTrack = MatchTriggerTrack(track, trackParam, triggerTrackStore, triggerStore);
177
178     UShort_t pattern = GetHitPattern(trackParam, matchedTriggerTrack, digitStore);
179     track->SetHitsPatternInTrigCh(pattern);
180   }
181 }
182
183
184 //______________________________________________________________________________
185 AliMUONTriggerTrack * 
186 AliMUONTrackHitPattern::MatchTriggerTrack(AliMUONTrack* track,
187                                           AliMUONTrackParam& trackParam,
188                                           const AliMUONVTriggerTrackStore& triggerTrackStore,
189                                           const AliMUONVTriggerStore& triggerStore) const
190 {
191   //
192   /// Match track with trigger track
193   //
194
195   Int_t matchTrigger = 0;
196   Int_t loTrgNum(-1);
197   Double_t distTriggerTrack[3], sigma2[3];
198   Double_t chi2;
199   Double_t chi2MatchTrigger = 0., minChi2MatchTrigger = 999.;
200   Int_t doubleMatch = -1; // Check if track matches 2 trigger tracks
201   Double_t doubleChi2 = -1.;
202   AliMUONTriggerTrack* doubleTriggerTrack = 0x0;
203   AliMUONTriggerTrack* matchedTriggerTrack = 0x0;
204     
205   const TMatrixD& kParamCov = trackParam.GetCovariances();
206     
207   Double_t xTrack = trackParam.GetNonBendingCoor();
208   Double_t yTrack = trackParam.GetBendingCoor();
209   Double_t ySlopeTrack = trackParam.GetBendingSlope();
210
211   // Covariance matrix 3x3 (X,Y,slopeY) for tracker tracks
212   TMatrixD trackCov(3,3);
213   trackCov.Zero();
214   trackCov(0,0) = kParamCov(0,0);
215   trackCov(1,1) = kParamCov(2,2);
216   trackCov(2,2) = kParamCov(3,3);
217   trackCov(1,2) = kParamCov(2,3);
218   trackCov(2,1) = kParamCov(3,2);
219
220   TMatrixD sumCov(trackCov,TMatrixD::kPlus,*fTrigCovariance);
221
222   Bool_t isCovOK = kTRUE;
223
224   if (sumCov.Determinant() != 0) {
225     sumCov.Invert();
226   } else {
227     AliWarning(" Determinant = 0");
228     isCovOK = kFALSE;
229     sigma2[0] = kParamCov(0,0);
230     sigma2[1] = kParamCov(2,2);
231     sigma2[2] = kParamCov(3,3);
232     // sigma of distributions (trigger-track) X,Y,slopeY
233     const Double_t kDistSigma[3]={AliMUONConstants::TriggerNonBendingReso(),
234                                   AliMUONConstants::TriggerBendingReso(),
235                                   1.414 * AliMUONConstants::TriggerBendingReso()/fDeltaZ};
236     for (Int_t iVar = 0; iVar < 3; iVar++) sigma2[iVar] += kDistSigma[iVar] * kDistSigma[iVar];
237   }
238
239   AliMUONTriggerTrack *triggerTrack;
240   TIter itTriggerTrack(triggerTrackStore.CreateIterator());
241   while ( ( triggerTrack = static_cast<AliMUONTriggerTrack*>(itTriggerTrack() ) ) )
242   {
243     distTriggerTrack[0] = triggerTrack->GetX11() - xTrack;
244     distTriggerTrack[1] = triggerTrack->GetY11() - yTrack;
245     distTriggerTrack[2] = TMath::Tan(triggerTrack->GetThetay()) - ySlopeTrack;
246
247     if(isCovOK){
248       TMatrixD paramDiff(3,1);
249       for(Int_t iVar = 0; iVar < 3; iVar++)
250         paramDiff(iVar,0) = distTriggerTrack[iVar];
251         
252       TMatrixD tmp(sumCov,TMatrixD::kMult,paramDiff);
253       TMatrixD chi2M(paramDiff,TMatrixD::kTransposeMult,tmp);
254       chi2 = chi2M(0,0);
255     }
256     else {
257       chi2 = 0.;
258       for (Int_t iVar = 0; iVar < 3; iVar++) chi2 += distTriggerTrack[iVar]*distTriggerTrack[iVar]/sigma2[iVar];
259     }
260
261     chi2 /= 3.; // Normalized Chi2: 3 degrees of freedom (X,Y,slopeY)
262     if (chi2 < AliMUONReconstructor::GetRecoParam()->GetMaxNormChi2MatchTrigger()) 
263     {
264       Bool_t isDoubleTrack = (TMath::Abs(chi2 - minChi2MatchTrigger)<1.);
265       if (chi2 < minChi2MatchTrigger && chi2 < AliMUONReconstructor::GetRecoParam()->GetMaxNormChi2MatchTrigger()) 
266       {
267         if(isDoubleTrack)
268         {
269           doubleMatch = loTrgNum;
270           doubleChi2 = chi2MatchTrigger;
271           doubleTriggerTrack = matchedTriggerTrack;
272         }
273         minChi2MatchTrigger = chi2;
274         chi2MatchTrigger = chi2;
275         loTrgNum = triggerTrack->GetLoTrgNum();
276         matchedTriggerTrack = triggerTrack;
277         AliMUONLocalTrigger* locTrg = triggerStore.FindLocal(loTrgNum);
278         matchTrigger = 1;
279         if(locTrg->LoLpt()>0) matchTrigger = 2;
280         if(locTrg->LoHpt()>0) matchTrigger = 3;
281       }
282       else if(isDoubleTrack) 
283       {
284         doubleMatch = triggerTrack->GetLoTrgNum();
285         doubleChi2 = chi2;
286       }
287     }
288   }
289   if(doubleMatch>=0)
290   { // If two trigger tracks match, select the one passing more trigger cuts
291     AliDebug(1, Form("Two candidates found: %i and %i",loTrgNum,doubleMatch));
292     AliMUONLocalTrigger* locTrg1 = triggerStore.FindLocal(doubleMatch);
293     if((locTrg1->LoLpt()>0 && matchTrigger<2) || (locTrg1->LoHpt() && matchTrigger<3))
294     {
295       if(locTrg1->LoHpt()>0) matchTrigger=3;
296       else matchTrigger = 2;
297       loTrgNum = doubleMatch;
298       chi2MatchTrigger = doubleChi2;
299       matchedTriggerTrack = doubleTriggerTrack;
300     }
301   }
302     
303   track->SetMatchTrigger(matchTrigger);
304   track->SetLoTrgNum(loTrgNum);
305   track->SetChi2MatchTrigger(chi2MatchTrigger);
306
307   AliMUONLocalTrigger* locTrg = static_cast<AliMUONLocalTrigger*>(triggerStore.FindLocal(loTrgNum));
308
309   if (locTrg)
310   {    
311     Int_t deviation = locTrg->GetDeviation(); 
312     track->SetLocalTrigger(locTrg->LoCircuit(),
313                            locTrg->LoStripX(),
314                            locTrg->LoStripY(),
315                            deviation,
316                            locTrg->LoLpt(),
317                            locTrg->LoHpt());
318   }
319
320   return matchedTriggerTrack;
321 }
322
323
324 //______________________________________________________________________________
325 UShort_t AliMUONTrackHitPattern::GetHitPattern(AliMUONTrackParam &trackParam,
326                                                AliMUONTriggerTrack* matchedTriggerTrack,
327                                                AliMUONVDigitStore& digitStore) const
328 {
329   //
330   /// Get hit pattern on trigger chambers for the current track
331   //
332   UShort_t pattern = 0;
333   Bool_t isMatch[2];
334   const Int_t kNTrackingCh = AliMUONConstants::NTrackingCh();
335
336   Bool_t patternFromTrigTrack = kFALSE;
337
338
339   // Calculate hit pattern from trigger track
340   if(matchedTriggerTrack){
341     patternFromTrigTrack = PerformTrigTrackMatch(pattern, matchedTriggerTrack, digitStore);
342   }
343
344   if(patternFromTrigTrack) return pattern;
345
346
347   // Calculate hit pattern from tracker track propagation
348   // if hit pattern from trigger track failed
349
350   for(Int_t ch=0; ch<4; ++ch)
351   {
352     Int_t iChamber = kNTrackingCh+ch;
353     AliMUONTrackExtrap::ExtrapToZCov(&trackParam, AliMUONConstants::DefaultChamberZ(iChamber));
354     FindPadMatchingTrack(digitStore, trackParam, isMatch, iChamber);
355     for(Int_t cath=0; cath<2; ++cath)
356     {
357       if(isMatch[cath]) SetBit(pattern, cath, ch);
358     }
359   }
360   return pattern;
361 }
362
363
364 //______________________________________________________________________________
365 void AliMUONTrackHitPattern::SetBit(UShort_t& pattern, Int_t cathode, Int_t chamber) const
366 {
367   //
368   /// Set hits pattern
369   //
370   const Int_t kMask[2][4]= {{0x80, 0x40, 0x20, 0x10},
371                             {0x08, 0x04, 0x02, 0x01}};
372   pattern |= kMask[cathode][chamber];
373 }
374
375
376 //______________________________________________________________________________
377 void AliMUONTrackHitPattern::AddEffInfo(UShort_t& pattern, Int_t slat, Int_t effType) const
378 {
379   //
380   /// Set info on efficiency calculation
381   //
382   pattern += effType << 8;
383   pattern += slat << 10;
384 }
385
386
387 //______________________________________________________________________________
388 void 
389 AliMUONTrackHitPattern::ApplyMCSCorrections(AliMUONTrackParam& trackParam) const
390 {
391   //
392   /// Returns uncertainties on extrapolated position.
393   /// Takes into account Branson plane corrections in the iron wall.
394   //
395
396   const Float_t kZFilterOut = AliMUONConstants::MuonFilterZEnd();
397   const Float_t kFilterThickness = TMath::Abs(kZFilterOut-AliMUONConstants::MuonFilterZBeg()); // cm
398
399   AliMUONTrackExtrap::ExtrapToZCov(&trackParam, kZFilterOut); // Extrap to muon filter end
400   AliMUONTrackExtrap::AddMCSEffect(&trackParam, kFilterThickness, AliMUONConstants::MuonFilterX0()); // Add MCS effects
401   return;
402 }
403
404
405 //______________________________________________________________________________
406 Bool_t 
407 AliMUONTrackHitPattern::TriggerDigits(const AliMUONVTriggerStore& triggerStore,
408                                       AliMUONVDigitStore& digitStore) const
409 {
410   //
411   /// make (S)Digit for trigger
412   //
413   
414   digitStore.Clear();
415   
416   AliMUONLocalTrigger* locTrg;
417   TIter next(triggerStore.CreateLocalIterator());
418   
419   while ( ( locTrg = static_cast<AliMUONLocalTrigger*>(next()) ) ) 
420   {
421     if (locTrg->IsNull()) continue;
422    
423     TArrayS xyPattern[2];
424     locTrg->GetXPattern(xyPattern[0]);
425     locTrg->GetYPattern(xyPattern[1]);
426
427     // do we need this ? (Ch.F.)
428 //     for(Int_t cath=0; cath<2; ++cath)
429 //     {
430 //       for(Int_t ch=0; ch<4; ++ch)
431 //       {
432 //         if(xyPattern[cath][ch]==0) continue;
433 //       }
434 //     }
435     
436     Int_t nBoard = locTrg->LoCircuit();
437     fDigitMaker.TriggerDigits(nBoard, xyPattern, digitStore);
438   }
439   return kTRUE;
440 }
441
442
443 //______________________________________________________________________________
444 void 
445 AliMUONTrackHitPattern::FindPadMatchingTrack(AliMUONVDigitStore& digitStore,
446                                              const AliMUONTrackParam& trackParam,
447                                              Bool_t isMatch[2], Int_t iChamber) const
448 {
449     //
450     /// Given the tracker track position, searches for matching digits.
451     //
452
453     Float_t minMatchDist[2];
454
455     for(Int_t cath=0; cath<2; ++cath)
456     {
457       isMatch[cath]=kFALSE;
458       minMatchDist[cath]=fkMaxDistance/10.;
459     }
460
461     TIter next(digitStore.CreateIterator());
462     AliMUONVDigit* mDigit;
463
464     while ( ( mDigit = static_cast<AliMUONVDigit*>(next()) ) )
465     {
466       Int_t currDetElemId = mDigit->DetElemId();
467       Int_t currCh = AliMpDEManager::GetChamberId(currDetElemId);
468       if(currCh!=iChamber) continue;
469       Int_t cathode = mDigit->Cathode();
470       Int_t ix = mDigit->PadX();
471       Int_t iy = mDigit->PadY();
472       Float_t xpad, ypad, zpad;
473       const AliMpVSegmentation* seg = AliMpSegmentation::Instance()
474         ->GetMpSegmentation(currDetElemId,AliMp::GetCathodType(cathode));
475       
476       AliMpPad pad = seg->PadByIndices(AliMpIntPair(ix,iy),kTRUE);
477       Float_t xlocal1 = pad.Position().X();
478       Float_t ylocal1 = pad.Position().Y();
479       Float_t dpx = pad.Dimensions().X();
480       Float_t dpy = pad.Dimensions().Y();
481       fTransformer.Local2Global(currDetElemId, xlocal1, ylocal1, 0, xpad, ypad, zpad);
482       Float_t matchDist = MinDistanceFromPad(xpad, ypad, zpad, dpx, dpy, trackParam);
483       if(matchDist>minMatchDist[cathode])continue;
484       isMatch[cathode] = kTRUE;
485       if(isMatch[0] && isMatch[1]) break;
486       minMatchDist[cathode] = matchDist;
487     }
488 }
489
490
491 //______________________________________________________________________________
492 Float_t 
493 AliMUONTrackHitPattern::MinDistanceFromPad(Float_t xPad, Float_t yPad, Float_t zPad,
494                                            Float_t dpx, Float_t dpy, 
495                                            const AliMUONTrackParam& trackParam) const
496 {
497     //
498     /// Decides if the digit belongs to the tracker track.
499     //
500
501     AliMUONTrackParam trackParamAtPadZ(trackParam);
502     AliMUONTrackExtrap::ExtrapToZCov(&trackParamAtPadZ, zPad);
503
504     Float_t xTrackAtPad = trackParamAtPadZ.GetNonBendingCoor();
505     Float_t yTrackAtPad = trackParamAtPadZ.GetBendingCoor();
506
507     const Float_t kNSigma = AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTrigger();
508
509     const TMatrixD& kCovParam = trackParamAtPadZ.GetCovariances();
510     
511     Float_t sigmaX = TMath::Sqrt(kCovParam(0,0));
512     Float_t sigmaY = TMath::Sqrt(kCovParam(2,2));
513
514     Float_t maxDistX = kNSigma * sigmaX; // in cm
515     Float_t maxDistY = kNSigma * sigmaY; // in cm
516
517     Float_t deltaX = TMath::Abs(xPad-xTrackAtPad)-dpx;
518     Float_t deltaY = TMath::Abs(yPad-yTrackAtPad)-dpy;
519
520     Float_t matchDist = fkMaxDistance;
521     if(deltaX<=maxDistX && deltaY<=maxDistY) matchDist = TMath::Max(deltaX, deltaY);
522
523     return matchDist;
524 }
525
526
527 //_____________________________________________________________________________
528 Int_t AliMUONTrackHitPattern::FindPadMatchingTrig(AliMUONVDigitStore& digitStore, Int_t &detElemId,
529                                                   Float_t coor[2], Bool_t isMatch[2],
530                                                   TArrayI nboard[2], TArrayF &zRealMatch, Float_t y11) const
531 {
532     //
533     /// Check slat and board number of digit matching trigger track
534     //
535
536     enum {kBending, kNonBending};
537
538     Float_t minMatchDist[fgkNcathodes];
539     Int_t padsInCheckArea[fgkNcathodes];
540
541     for(Int_t cath=0; cath<fgkNcathodes; cath++){
542         isMatch[cath] = kFALSE;
543         minMatchDist[cath] = fkMaxDistance/10.;
544         padsInCheckArea[cath] = 0;
545     }
546     Int_t iChamber = AliMpDEManager::GetChamberId(detElemId);
547     Int_t ch = iChamber-10;
548     Float_t oldDeltaZ = AliMUONConstants::DefaultChamberZ(iChamber) - AliMUONConstants::DefaultChamberZ(10);
549     Float_t y = coor[1];
550     Int_t iSlat = detElemId%100;
551     Int_t trigDigitBendPlane = -1;
552     Int_t foundDetElemId = detElemId;
553     Float_t foundZmatch=999.;
554     Float_t yCoorAtPadZ=999.;
555
556     TIter next(digitStore.CreateIterator());
557     AliMUONVDigit* mDigit;
558     Int_t idigit=0;
559     
560     while ( ( mDigit = static_cast<AliMUONVDigit*>(next()) ) )
561     {
562         idigit++;
563         Int_t currDetElemId = mDigit->DetElemId();
564         Int_t currCh = AliMpDEManager::GetChamberId(currDetElemId);
565         if(currCh!=iChamber) continue;
566         Int_t currSlat = currDetElemId%100;
567         Int_t slatDiff = TMath::Abs(currSlat-iSlat);
568         if(slatDiff>1 && slatDiff<17) continue; // Check neighbour slats
569         Int_t cathode = mDigit->Cathode();
570         Int_t ix = mDigit->PadX();
571         Int_t iy = mDigit->PadY();
572         Float_t xpad, ypad, zpad;
573         const AliMpVSegmentation* seg = AliMpSegmentation::Instance()
574             ->GetMpSegmentation(currDetElemId,AliMp::GetCathodType(cathode));
575
576         AliMpPad pad = seg->PadByIndices(AliMpIntPair(ix,iy),kTRUE);
577         Float_t xlocal1 = pad.Position().X();
578         Float_t ylocal1 = pad.Position().Y();
579         Float_t dpx = pad.Dimensions().X();
580         Float_t dpy = pad.Dimensions().Y();
581         fTransformer.Local2Global(currDetElemId, xlocal1, ylocal1, 0, xpad, ypad, zpad);
582         AliDebug(2, Form("\nDetElemId = %i  Cathode = %i  Pad = (%i,%i) = (%.2f,%.2f)  Dim = (%.2f,%.2f)  Track = (%.2f,%.2f)\n",currDetElemId,cathode,ix,iy,xpad,ypad,dpx,dpy,coor[0],coor[1]));
583         // searching track intersection with chambers (second approximation)
584         if(ch%2==1){
585             //if(iChamber%2==1){
586             Float_t deltaZ = zpad - zRealMatch[0];
587             y = (coor[1]-y11)*deltaZ/oldDeltaZ + y11;
588             if(TMath::Abs(y-coor[1])>0.1) AliDebug(3, Form("oldDeltaZ = %7.2f   newDeltaZ = %7.2f\toldY = %7.2f   new y = %7.2f\n",oldDeltaZ,deltaZ,coor[1],y));
589         }
590         Float_t matchDist = PadMatchTrack(xpad, ypad, dpx, dpy, coor[0], y);
591         if(matchDist<fkMaxDistance/2.) padsInCheckArea[cathode]++;
592         if(matchDist>minMatchDist[cathode])continue;
593         isMatch[cathode] = kTRUE;
594         minMatchDist[cathode] = matchDist;
595         foundDetElemId = currDetElemId;
596         foundZmatch=zpad;
597         yCoorAtPadZ=y;
598         if(cathode==kBending) trigDigitBendPlane = idigit;
599         for (Int_t loc=0; loc<pad.GetNofLocations(); loc++){
600             AliMpIntPair location = pad.GetLocation(loc);
601             nboard[cathode][loc] = location.GetFirst();
602         }
603         for(Int_t loc=pad.GetNofLocations(); loc<fgkNlocations; loc++){
604             nboard[cathode][loc]=-1;
605         }
606     }
607
608     for(Int_t cath=0; cath<fgkNcathodes; cath++){
609         if(padsInCheckArea[cath]>2) {
610           AliDebug(1, Form("padsInCheckArea[%i] = %i\n",cath,padsInCheckArea[cath]));
611             return -500;
612         }
613     }
614
615     if(isMatch[kBending] || isMatch[kNonBending]){
616         detElemId = foundDetElemId;
617         zRealMatch[ch] = foundZmatch;
618         coor[1] = yCoorAtPadZ;
619     }
620     return trigDigitBendPlane;
621 }
622
623 //_____________________________________________________________________________
624 Float_t AliMUONTrackHitPattern::PadMatchTrack(Float_t xPad, Float_t yPad,
625                                                 Float_t dpx, Float_t dpy, 
626                                                 Float_t xTrackAtPad, Float_t yTrackAtPad) const
627 {
628     //
629     /// Decides if the digit belongs to the trigger track.
630     //
631
632   Float_t maxDist = AliMUONReconstructor::GetRecoParam()->GetStripCutForTrigger() * 2. * TMath::Min(dpx,dpy); // cm
633   if(maxDist<2.) maxDist = 2.;
634   Float_t maxDistCheckArea = AliMUONReconstructor::GetRecoParam()->GetMaxStripAreaForTrigger() * 2. *  TMath::Min(dpx,dpy); // cm
635
636     Float_t matchDist = fkMaxDistance;
637
638     Float_t deltaX = TMath::Abs(xPad-xTrackAtPad)-dpx;
639     Float_t deltaY = TMath::Abs(yPad-yTrackAtPad)-dpy;
640     Float_t maxDistX = maxDist;
641     Float_t maxDistY = maxDist;
642
643     if(deltaX<=maxDistX && deltaY<=maxDistY) matchDist = TMath::Max(deltaX, deltaY);
644     else if(deltaX<=maxDistCheckArea && deltaY<=maxDistCheckArea) matchDist = fkMaxDistance/5.;
645     return matchDist;
646 }
647
648
649 //_____________________________________________________________________________
650 Int_t AliMUONTrackHitPattern::DetElemIdFromPos(Float_t x, Float_t y, 
651                                                  Int_t chamber, Int_t cathode) const
652 {
653     //
654     /// Given the (x,y) position in the chamber,
655     /// it returns the corresponding slat
656     //
657
658     Int_t resultingDetElemId = -1;
659     AliMpDEIterator it;
660     Float_t minDist = 999.;
661     for ( it.First(chamber-1); ! it.IsDone(); it.Next() ){
662         Int_t detElemId = it.CurrentDEId();
663         Int_t ich = detElemId/100-10;
664         Float_t tolerance=0.2*((Float_t)ich);
665         Float_t currDist=9999.;
666
667         const AliMpVSegmentation* seg = 
668             AliMpSegmentation::Instance()
669             ->GetMpSegmentation(detElemId,AliMp::GetCathodType(cathode));
670         if (!seg) continue;
671
672         Float_t deltax = seg->Dimensions().X();
673         Float_t deltay = seg->Dimensions().Y();
674         Float_t xlocal1 =  -deltax;
675         Float_t ylocal1 =  -deltay;
676         Float_t xlocal2 =  +deltax;
677         Float_t ylocal2 =  +deltay;
678         Float_t xg01, yg01, zg1, xg02, yg02, zg2;
679         fTransformer.Local2Global(detElemId, xlocal1, ylocal1, 0, xg01, yg01, zg1);
680         fTransformer.Local2Global(detElemId, xlocal2, ylocal2, 0, xg02, yg02, zg2);
681
682         Float_t xg1 = xg01, xg2 = xg02, yg1 = yg01, yg2 = yg02;
683
684         if(xg01>xg02){
685             xg1 = xg02;
686             xg2 = xg01;
687         }
688         if(yg01>yg02){
689             yg1 = yg02;
690             yg2 = yg01;
691         }
692
693         if(x>=xg1-tolerance && x<=xg2+tolerance && y>=yg1-tolerance && y<=yg2+tolerance){ // takes into account errors in extrapolation
694             if(y<yg1) currDist = yg1-y;
695             else if(y>yg2) currDist = y-yg2;
696             if(currDist<minDist) {
697                 resultingDetElemId = detElemId;
698                 minDist=currDist;
699                 continue;
700             }
701             resultingDetElemId = detElemId;
702             break;
703         }
704     } // loop on detElemId
705     return resultingDetElemId;
706 }
707
708
709 //_____________________________________________________________________________
710 void AliMUONTrackHitPattern::LocalBoardFromPos(Float_t x, Float_t y,
711                                                  Int_t detElemId, Int_t cathode,
712                                                  Int_t localBoard[4]) const
713 {
714     //
715     /// Given the (x,y) position in the chamber,
716     /// it returns the corresponding local board
717     //
718
719     for(Int_t loc=0; loc<fgkNlocations; loc++){
720         localBoard[loc]=-1;
721     }
722     Float_t xl, yl, zl;
723     fTransformer.Global2Local(detElemId, x, y, 0, xl, yl, zl);
724     TVector2 pos(xl,yl);
725     const AliMpVSegmentation* seg = 
726         AliMpSegmentation::Instance()
727           ->GetMpSegmentation(detElemId,AliMp::GetCathodType(cathode));
728     if (seg){
729         AliMpPad pad = seg->PadByPosition(pos,kFALSE);
730         for (Int_t loc=0; loc<pad.GetNofLocations(); loc++){
731             AliMpIntPair location = pad.GetLocation(loc);
732             localBoard[loc] = location.GetFirst();
733         }
734     }
735 }
736
737
738 //_____________________________________________________________________________
739 Bool_t AliMUONTrackHitPattern::PerformTrigTrackMatch(UShort_t &pattern,
740                                                      AliMUONTriggerTrack *matchedTrigTrack,
741                                                      AliMUONVDigitStore& digitStore) const
742 {
743   //
744   /// It searches for matching digits around the trigger track.
745   //
746
747   enum {kBending, kNonBending};
748
749   Int_t chOrder[fgkNchambers] = {0,2,1,3};
750
751   TArrayF zRealMatch(fgkNchambers);
752   TArrayF correctFactor(fgkNcathodes);
753
754   Bool_t isMatch[fgkNcathodes];
755   for(Int_t cath=0; cath<fgkNcathodes; cath++){
756     isMatch[cath] = kFALSE;
757   }
758
759   TArrayF zMeanChamber(fgkNchambers);
760   for(Int_t ch=0; ch<fgkNchambers; ch++){
761     zMeanChamber[ch] = AliMUONConstants::DefaultChamberZ(10+ch);
762   }
763
764   TArrayI digitPerTrack(fgkNcathodes);
765
766   Float_t trackIntersectCh[fgkNchambers][fgkNcathodes];
767
768   TArrayI triggeredDigits;
769   triggeredDigits.Set(fgkNchambers);
770   triggeredDigits.Reset(-1);
771
772   TArrayI trigScheme[fgkNcathodes];
773   TArrayI slatThatTriggered[fgkNcathodes];
774   for(Int_t cath=0; cath<fgkNcathodes; cath++){
775     trigScheme[cath].Set(fgkNchambers);
776     slatThatTriggered[cath].Set(fgkNchambers);
777   }
778
779   Int_t boardThatTriggered[fgkNchambers][fgkNcathodes][fgkNlocations];
780   TArrayI nboard[fgkNcathodes];
781   for(Int_t cath=0; cath<fgkNcathodes; cath++){
782     nboard[cath].Set(fgkNlocations);
783   }
784   Int_t ineffBoard[fgkNlocations];
785   for(Int_t loc=0; loc<fgkNlocations; loc++){
786     ineffBoard[loc] = -1;
787   }
788
789   digitPerTrack.Reset();
790   for(Int_t ch=0; ch<fgkNchambers; ch++){
791     zRealMatch[ch] = zMeanChamber[ch];
792     for(Int_t cath=0; cath<fgkNcathodes; cath++){
793       for(Int_t loc=0; loc<fgkNlocations; loc++){
794         boardThatTriggered[ch][cath][loc]=-1;
795       }
796     }
797   }
798
799   for(Int_t cath=0; cath<fgkNcathodes; cath++){
800     slatThatTriggered[cath].Reset(-1);
801     trigScheme[cath].Reset();
802   }
803
804   Bool_t isClearEvent = kTRUE;
805
806   //Float_t x11 = matchedTrigTrack->GetX11();// x position (info from non-bending plane)
807   Float_t y11 = matchedTrigTrack->GetY11();// y position (info from bending plane)
808   Float_t thetaX = matchedTrigTrack->GetThetax();
809   Float_t thetaY = matchedTrigTrack->GetThetay();
810
811   for(Int_t ch=0; ch<fgkNchambers; ch++) { // chamber loop
812     Int_t currCh = chOrder[ch];
813     AliDebug(3, Form("zMeanChamber[%i] = %.2f\tzRealMatch[0] = %.2f\n",currCh,zMeanChamber[currCh],zRealMatch[0]));
814
815     for(Int_t cath=0; cath<fgkNcathodes; cath++){
816       correctFactor[cath]=1.;
817     }
818     // calculate corrections to trigger track theta
819     if(ch>=1) correctFactor[kNonBending] = zMeanChamber[0]/zRealMatch[0];// corrects x position
820     if(ch>=2) correctFactor[kBending] = (zMeanChamber[2] - zMeanChamber[0]) / (zRealMatch[2] - zRealMatch[0]);// corrects y position
821
822     // searching track intersection with chambers (first approximation)
823     Float_t deltaZ = zMeanChamber[currCh] - zMeanChamber[0];
824     trackIntersectCh[currCh][0] = zMeanChamber[currCh] * TMath::Tan(thetaX) * correctFactor[kNonBending];// x position (info from non-bending plane) 
825     trackIntersectCh[currCh][1] = y11 + deltaZ * TMath::Tan(thetaY) * correctFactor[kBending];// y position (info from bending plane)
826     Int_t detElemIdFromTrack = DetElemIdFromPos(trackIntersectCh[currCh][0], trackIntersectCh[currCh][1], 11+currCh, 0);
827     if(detElemIdFromTrack<0) {
828       AliDebug(1, "Warning: trigger track outside trigger chamber\n");
829       continue;
830     }
831                 
832     triggeredDigits[currCh] = FindPadMatchingTrig(digitStore, detElemIdFromTrack, trackIntersectCh[currCh], isMatch, nboard, zRealMatch, y11);
833
834     // if FindPadMatchingTrig = -500 => too many digits matching pad =>
835     //                               => Event not clear => Reject track
836     if(triggeredDigits[currCh]<-100){
837       isClearEvent = kFALSE;
838       AliDebug(1, Form("Warning: track = %p (%i) matches many pads. Rejected!\n",(void *)matchedTrigTrack, detElemIdFromTrack));
839       break;
840     }
841
842     for(Int_t cath=0; cath<fgkNcathodes; cath++){
843       if(!isMatch[cath]) continue;
844       SetBit(pattern, cath, currCh);
845       digitPerTrack[cath]++;
846       trigScheme[cath][currCh]++;
847       slatThatTriggered[cath][currCh] = detElemIdFromTrack;
848       for(Int_t loc=0; loc<fgkNlocations; loc++){
849         boardThatTriggered[currCh][cath][loc] = nboard[cath][loc];
850       }
851     }
852   } // end chamber loop
853
854   for(Int_t cath=0; cath<fgkNcathodes; cath++){
855     if(digitPerTrack[cath]<3) isClearEvent = kFALSE;
856     if(!isClearEvent) AliDebug(1, Form("Warning: found %i digits for trigger track cathode %i.\nRejecting event\n", digitPerTrack[cath],cath));
857   }
858
859   if(!isClearEvent) return kFALSE;
860
861   Int_t goodForEff = kBoardEff;
862
863   Int_t ineffSlat = -1;
864   Int_t ineffDetElId = -1;
865   Int_t firstSlat = slatThatTriggered[kBending][0]%100;
866   if(firstSlat<0) firstSlat = slatThatTriggered[kBending][1]%100;
867   Int_t firstBoard = boardThatTriggered[0][kBending][0];
868   if(firstBoard<0) firstBoard = boardThatTriggered[1][kBending][0];
869   for(Int_t ch=0; ch<fgkNchambers; ch++){
870     Bool_t isCurrChIneff = kFALSE;
871     Int_t currSlat = slatThatTriggered[kBending][ch]%100;
872     if(currSlat<0){
873       ineffDetElId = DetElemIdFromPos(trackIntersectCh[ch][0], trackIntersectCh[ch][1], 11+ch, kBending);
874       currSlat = ineffDetElId%100;
875       ineffSlat = currSlat;
876       isCurrChIneff = kTRUE;
877     }
878     if(currSlat!=firstSlat) {
879       AddEffInfo(pattern, 20, kChEff);
880       return kTRUE;
881     }
882     Bool_t atLeastOneLoc=kFALSE;
883     if(isCurrChIneff) LocalBoardFromPos(trackIntersectCh[ch][0], trackIntersectCh[ch][1], ineffDetElId, kBending, ineffBoard);
884     for(Int_t loc=0; loc<fgkNlocations; loc++){
885       Int_t currBoard = boardThatTriggered[ch][kBending][loc];
886       if(isCurrChIneff) currBoard = ineffBoard[loc];
887       if(currBoard==firstBoard){
888         atLeastOneLoc=kTRUE;
889         break;
890       }
891     }
892     if(!atLeastOneLoc) goodForEff = kSlatEff;
893   } // end chamber loop
894   
895   AddEffInfo(pattern, firstSlat, goodForEff);
896   return kTRUE;
897 }