2 // origin: hough/AliL3HoughTrack.cxx,v 1.23 ue Mar 28 18:05:12 2006 UTC by alibrary
4 // Author: Anders Vestbo <mailto:vestbo@fi.uib.no>
5 //*-- Copyright © ALICE HLT Group
7 #include "AliHLTStandardIncludes.h"
9 #include "AliHLTLogging.h"
10 #include "AliHLTTrack.h"
11 #include "AliHLTTPCHoughTrack.h"
12 #include "AliHLTTransform.h"
13 #include "AliHLTHoughTransformerRow.h"
19 /** \class AliHLTTPCHoughTrack
21 //_____________________________________________________________
22 // AliHLTTPCHoughTrack
24 // Track class for Hough tracklets
29 ClassImp(AliHLTTPCHoughTrack)
32 AliHLTTPCHoughTrack::AliHLTTPCHoughTrack() : AliHLTTrack()
43 ComesFromMainVertex(kTRUE);
46 AliHLTTPCHoughTrack::~AliHLTTPCHoughTrack()
51 void AliHLTTPCHoughTrack::Set(AliHLTTrack *track)
53 //Basically copy constructor
54 AliHLTTPCHoughTrack *tpt = (AliHLTTPCHoughTrack*)track;
55 SetTrackParameters(tpt->GetKappa(),tpt->GetPsi(),tpt->GetWeight());
56 SetEtaIndex(tpt->GetEtaIndex());
57 SetEta(tpt->GetEta());
58 SetTgl(tpt->GetTgl());
59 SetPsi(tpt->GetPsi());
60 SetPterr(tpt->GetPterr());
61 SetTglerr(tpt->GetTglerr());
62 SetPsierr(tpt->GetPsierr());
63 SetCenterX(tpt->GetCenterX());
64 SetCenterY(tpt->GetCenterY());
65 SetFirstPoint(tpt->GetFirstPointX(),tpt->GetFirstPointY(),tpt->GetFirstPointZ());
66 SetLastPoint(tpt->GetLastPointX(),tpt->GetLastPointY(),tpt->GetLastPointZ());
67 SetCharge(tpt->GetCharge());
68 SetRowRange(tpt->GetFirstRow(),tpt->GetLastRow());
69 SetSlice(tpt->GetSlice());
70 SetHits(tpt->GetNHits(),(UInt_t *)tpt->GetHitNumbers());
71 SetMCid(tpt->GetMCid());
72 SetBinXY(tpt->GetBinX(),tpt->GetBinY(),tpt->GetSizeX(),tpt->GetSizeY());
73 SetSector(tpt->GetSector());
76 // fWeight = tpt->GetWeight();
77 // fDLine = tpt->GetDLine();
78 // fPsiLine = tpt->GetPsiLine();
79 // SetNHits(tpt->GetWeight());
80 // SetRowRange(tpt->GetFirstRow(),tpt->GetLastRow());
84 Int_t AliHLTTPCHoughTrack::Compare(const AliHLTTrack *tpt) const
86 //Compare 2 hough tracks according to their weight
87 AliHLTTPCHoughTrack *track = (AliHLTTPCHoughTrack*)tpt;
88 if(track->GetWeight() < GetWeight()) return 1;
89 if(track->GetWeight() > GetWeight()) return -1;
93 void AliHLTTPCHoughTrack::SetEta(Double_t f)
95 //Set eta, and calculate fTanl, which is the tan of dipangle
98 Double_t theta = 2*atan(exp(-1.*fEta));
99 Double_t dipangle = AliHLTTransform::PiHalf() - theta;
100 Double_t tgl = tan(dipangle);
104 void AliHLTTPCHoughTrack::UpdateToFirstRow()
106 //Update the track parameters to the point where track cross
109 //Get the crossing point with the first padrow:
111 if(!GetCrossingPoint(GetFirstRow(),xyz))
112 LOG(AliHLTLog::kWarning,"AliHLTTPCHoughTrack::UpdateToFirstRow()","Track parameters")
113 <<AliHLTLog::kDec<<"Track does not cross padrow "<<GetFirstRow()<<" centerx "
114 <<GetCenterX()<<" centery "<<GetCenterY()<<" Radius "<<GetRadius()<<" tgl "<<GetTgl()<<ENDLOG;
116 //printf("Track with eta %f tgl %f crosses at x %f y %f z %f on padrow %d\n",GetEta(),GetTgl(),xyz[0],xyz[1],xyz[2],GetFirstRow());
117 //printf("Before: first %f %f %f tgl %f center %f %f charge %d\n",GetFirstPointX(),GetFirstPointY(),GetFirstPointZ(),GetTgl(),GetCenterX(),GetCenterY(),GetCharge());
119 Double_t radius = sqrt(xyz[0]*xyz[0] + xyz[1]*xyz[1]);
121 //Get the track parameters
124 Double_t x0 = GetR0() * cos(GetPhi0()) ;
125 Double_t y0 = GetR0() * sin(GetPhi0()) ;
127 Double_t rc = GetRadius();//fabs(GetPt()) / AliHLTTransform::GetBFieldValue();
128 Double_t tPhi0 = GetPsi() + GetCharge() * AliHLTTransform::PiHalf() / abs(GetCharge()) ;
129 Double_t xc = GetCenterX();//x0 - rc * cos(tPhi0) ;
130 Double_t yc = GetCenterY();//y0 - rc * sin(tPhi0) ;
132 //Check helix and cylinder intersect
133 Double_t fac1 = xc*xc + yc*yc ;
134 Double_t sfac = sqrt( fac1 ) ;
136 if ( fabs(sfac-rc) > radius || fabs(sfac+rc) < radius ) {
137 LOG(AliHLTLog::kError,"AliHLTTPCHoughTrack::UpdateToFirstRow","Tracks")<<AliHLTLog::kDec<<
138 "Track does not intersect"<<ENDLOG;
143 Double_t fac2 = (radius*radius + fac1 - rc*rc) / (2.00 * radius * sfac ) ;
144 Double_t phi = atan2(yc,xc) + GetCharge()*acos(fac2) ;
145 Double_t td = atan2(radius*sin(phi) - yc,radius*cos(phi) - xc) ;
148 if ( td < 0 ) td = td + AliHLTTransform::TwoPi();
149 Double_t deltat = fmod((-GetCharge()*td + GetCharge()*tPhi0),AliHLTTransform::TwoPi());
150 if ( deltat < 0. ) deltat += AliHLTTransform::TwoPi();
151 else if ( deltat > AliHLTTransform::TwoPi() ) deltat -= AliHLTTransform::TwoPi();
152 Double_t z = GetZ0() + rc * GetTgl() * deltat ;
154 Double_t xExtra = radius * cos(phi) ;
155 Double_t yExtra = radius * sin(phi) ;
157 Double_t tPhi = atan2(yExtra-yc,xExtra-xc);
159 //if ( tPhi < 0 ) tPhi += 2. * M_PI ;
160 Double_t tPsi = tPhi - GetCharge() * AliHLTTransform::PiHalf() / abs(GetCharge()) ;
161 if ( tPsi > AliHLTTransform::TwoPi() ) tPsi -= AliHLTTransform::TwoPi() ;
162 else if ( tPsi < 0. ) tPsi += AliHLTTransform::TwoPi();
164 //And finally, update the track parameters
169 SetFirstPoint(xyz[0],xyz[1],z);
170 //printf("After: first %f %f %f tgl %f center %f %f charge %d\n",GetFirstPointX(),GetFirstPointY(),GetFirstPointZ(),GetTgl(),GetCenterX(),GetCenterY(),GetCharge());
172 //printf("First point set %f %f %f\n",xyz[0],xyz[1],z);
174 //Also, set the coordinates of the point where track crosses last padrow:
175 GetCrossingPoint(GetLastRow(),xyz);
176 SetLastPoint(xyz[0],xyz[1],xyz[2]);
177 //printf("last point %f %f %f\n",xyz[0],xyz[1],xyz[2]);
180 void AliHLTTPCHoughTrack::SetTrackParameters(Double_t kappa,Double_t eangle,Int_t weight)
182 //Set track parameters - sort of ctor
186 Double_t pt = fabs(AliHLTTransform::GetBFieldValue()/kappa);
188 Double_t radius = 1/fabs(kappa);
190 SetFirstPoint(0,0,0);
191 SetPsi(eangle); //Psi = emission angle when first point is vertex
192 SetPhi0(0); //not defined for vertex reference point
194 Double_t charge = -1.*kappa;
195 SetCharge((Int_t)copysign(1.,charge));
196 Double_t trackPhi0 = GetPsi() + charge*0.5*AliHLTTransform::Pi()/fabs(charge);
197 Double_t xc = GetFirstPointX() - GetRadius() * cos(trackPhi0) ;
198 Double_t yc = GetFirstPointY() - GetRadius() * sin(trackPhi0) ;
201 SetNHits(1); //just for the trackarray IO
205 void AliHLTTPCHoughTrack::SetTrackParametersRow(Double_t alpha1,Double_t alpha2,Double_t eta,Int_t weight)
207 //Set track parameters for HoughTransformerRow
208 //This includes curvature,emission angle and eta
209 Double_t psi = atan((alpha1-alpha2)/(AliHLTHoughTransformerRow::GetBeta1()-AliHLTHoughTransformerRow::GetBeta2()));
210 Double_t kappa = 2.0*(alpha1*cos(psi)-AliHLTHoughTransformerRow::GetBeta1()*sin(psi));
211 SetTrackParameters(kappa,psi,weight);
214 Double_t etaparam1 = AliHLTHoughTransformerRow::GetEtaCalcParam1();
215 Double_t etaparam2 = AliHLTHoughTransformerRow::GetEtaCalcParam2();
217 zovr = (etaparam1 - sqrt(etaparam1*etaparam1 - 4.*etaparam2*eta))/(2.*etaparam2);
219 zovr = -1.*(etaparam1 - sqrt(etaparam1*etaparam1 + 4.*etaparam2*eta))/(2.*etaparam2);
220 Double_t r = sqrt(1.+zovr*zovr);
221 Double_t exacteta = 0.5*log((1+zovr/r)/(1-zovr/r));
225 void AliHLTTPCHoughTrack::SetLineParameters(Double_t psi,Double_t D,Int_t weight,Int_t *rowrange,Int_t /*ref_row*/)
227 //Initialize a track piece, not yet a track
228 //Used in case of straight line transformation
230 //Transform line parameters to coordinate system of slice:
232 // D = D + fTransform->Row2X(ref_row)*cos(psi);
238 SetRowRange(rowrange[0],rowrange[1]);
242 void AliHLTTPCHoughTrack::SetBestMCid(Int_t mcid,Double_t mindist)
244 //Finds and set the closest mc label
245 if(mindist < fMinDist)
252 void AliHLTTPCHoughTrack::GetLineCrossingPoint(Int_t padrow,Float_t *xy)
254 //Returns the crossing point of the track with a given padrow
257 printf("AliHLTTPCHoughTrack::GetLineCrossingPoint : Track is not a line\n");
261 Float_t xhit = AliHLTTransform::Row2X(padrow) - AliHLTTransform::Row2X(GetFirstRow());
262 Float_t a = -1/tan(fPsiLine);
263 Float_t b = fDLine/sin(fPsiLine);
264 Float_t yhit = a*xhit + b;