SetNHits, in order to make the IO work in memhandler class.
[u/mrichter/AliRoot.git] / HLT / hough / AliL3HoughTrack.cxx
CommitLineData
b1886074 1//$Id$
2
3// Author: Anders Vestbo <mailto:vestbo@fi.uib.no>
4//*-- Copyright &copy ASV
d712b5b8 5
6#include <math.h>
7
8#include "AliL3Logging.h"
9#include "AliL3Transform.h"
10#include "AliL3Defs.h"
11#include "AliL3HoughTrack.h"
12
b1886074 13//_____________________________________________________________
14// AliL3HoughTrack
15//
16// Track class for Hough tracklets
17
d712b5b8 18ClassImp(AliL3HoughTrack)
19
20
21AliL3HoughTrack::AliL3HoughTrack()
22{
23 //Constructor
24
25 fWeight = 0;
26 fMinDist=0;
27 fTransform = new AliL3Transform();
28 fDLine = 0;
29 fPsiLine = 0;
30 fIsHelix = true;
31 fEtaIndex = -1;
32}
33
34
35AliL3HoughTrack::~AliL3HoughTrack()
36{
37 //Destructor
38 if(fTransform)
39 delete fTransform;
40}
41
42void AliL3HoughTrack::Set(AliL3Track *track)
43{
44
45 AliL3HoughTrack *tpt = (AliL3HoughTrack*)track;
46 SetTrackParameters(tpt->GetKappa(),tpt->GetPhi0(),tpt->GetWeight());
47 SetEtaIndex(tpt->GetEtaIndex());
48 SetEta(tpt->GetEta());
ae4d5136 49 SetTgl(tpt->GetTgl());
d712b5b8 50 SetPsi(tpt->GetPsi());
51 SetCenterX(tpt->GetCenterX());
52 SetCenterY(tpt->GetCenterY());
53 SetFirstPoint(tpt->GetFirstPointX(),tpt->GetFirstPointY(),tpt->GetFirstPointZ());
54 SetLastPoint(tpt->GetLastPointX(),tpt->GetLastPointY(),tpt->GetLastPointZ());
55 SetCharge(tpt->GetCharge());
56 SetRowRange(tpt->GetFirstRow(),tpt->GetLastRow());
b1886074 57 SetSlice(tpt->GetSlice());
242c143e 58 SetNHits(1);
d712b5b8 59 return;
60
61 fWeight = tpt->GetWeight();
62 fDLine = tpt->GetDLine();
63 fPsiLine = tpt->GetPsiLine();
64 SetNHits(tpt->GetWeight());
65 SetRowRange(tpt->GetFirstRow(),tpt->GetLastRow());
66 fIsHelix = false;
67
68
69}
70
71Int_t AliL3HoughTrack::Compare(const AliL3Track *tpt) const
72{
73 AliL3HoughTrack *track = (AliL3HoughTrack*)tpt;
74 if(track->GetWeight() < GetWeight()) return 1;
75 if(track->GetWeight() > GetWeight()) return -1;
76 return 0;
77}
78
79void AliL3HoughTrack::SetEta(Double_t f)
80{
b1886074 81 //Set eta, and calculate fTanl, which is the tan of dipangle
82
d712b5b8 83 fEta = f;
84 Double_t theta = 2*atan(exp(-1.*fEta));
8b007a2d 85 Double_t dipangle = Pi/2 - theta;
86 Double_t tgl = tan(dipangle);
d712b5b8 87 SetTgl(tgl);
88}
89
90void AliL3HoughTrack::CalculateHelix()
91{
92 return;
93}
94
95void AliL3HoughTrack::UpdateToFirstRow()
96{
97 //Update the track parameters to the point where track cross
98 //its first padrow.
99
100 //Get the crossing point with the first padrow:
101 Float_t xyz[3];
102 if(!GetCrossingPoint(GetFirstRow(),xyz))
103 LOG(AliL3Log::kWarning,"AliL3HoughTrack::UpdateToFirstRow()","Track parameters")
104 <<AliL3Log::kDec<<"Track does not cross padrow "<<GetFirstRow()<<" centerx "
105 <<GetCenterX()<<" centery "<<GetCenterY()<<" Radius "<<GetRadius()<<" tgl "<<GetTgl()<<ENDLOG;
106
8b007a2d 107 //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());
108 //printf("Before: first %f %f %f tgl %f center %f %f charge %d\n",GetFirstPointX(),GetFirstPointY(),GetFirstPointZ(),GetTgl(),GetCenterX(),GetCenterY(),GetCharge());
109
d712b5b8 110 Double_t radius = sqrt(xyz[0]*xyz[0] + xyz[1]*xyz[1]);
111
112 //Get the track parameters
b1886074 113
114 /*
115 Double_t x0 = GetR0() * cos(GetPhi0()) ;
116 Double_t y0 = GetR0() * sin(GetPhi0()) ;
117 */
118 Double_t rc = GetRadius();//fabs(GetPt()) / ( BFACT * BField ) ;
d712b5b8 119 Double_t tPhi0 = GetPsi() + GetCharge() * 0.5 * pi / fabs(GetCharge()) ;
b1886074 120 Double_t xc = GetCenterX();//x0 - rc * cos(tPhi0) ;
121 Double_t yc = GetCenterY();//y0 - rc * sin(tPhi0) ;
d712b5b8 122
123 //Check helix and cylinder intersect
124 Double_t fac1 = xc*xc + yc*yc ;
125 Double_t sfac = sqrt( fac1 ) ;
b1886074 126
d712b5b8 127 if ( fabs(sfac-rc) > radius || fabs(sfac+rc) < radius ) {
128 LOG(AliL3Log::kError,"AliL3HoughTrack::UpdateToFirstRow","Tracks")<<AliL3Log::kDec<<
129 "Track does not intersect"<<ENDLOG;
130 return;
131 }
132
133 //Find intersection
134 Double_t fac2 = ( radius*radius + fac1 - rc*rc) / (2.00 * radius * sfac ) ;
135 Double_t phi = atan2(yc,xc) + GetCharge()*acos(fac2) ;
136 Double_t td = atan2(radius*sin(phi) - yc,radius*cos(phi) - xc) ;
137
138 //Intersection in z
139 if ( td < 0 ) td = td + 2. * pi ;
140 Double_t deltat = fmod((-GetCharge()*td + GetCharge()*tPhi0),2*pi) ;
141 if ( deltat < 0. ) deltat += 2. * pi ;
142 if ( deltat > 2.*pi ) deltat -= 2. * pi ;
143 Double_t z = GetZ0() + rc * GetTgl() * deltat ;
8b007a2d 144
d712b5b8 145
146 Double_t xExtra = radius * cos(phi) ;
147 Double_t yExtra = radius * sin(phi) ;
148
149 Double_t tPhi = atan2(yExtra-yc,xExtra-xc);
150
151 //if ( tPhi < 0 ) tPhi += 2. * M_PI ;
152
153 Double_t tPsi = tPhi - GetCharge() * 0.5 * pi / fabs(GetCharge()) ;
154 if ( tPsi > 2. * pi ) tPsi -= 2. * pi ;
155 if ( tPsi < 0. ) tPsi += 2. * pi ;
156
157 //And finally, update the track parameters
d712b5b8 158 SetR0(radius);
159 SetPhi0(phi);
160 SetZ0(z);
161 SetPsi(tPsi);
162 SetFirstPoint(xyz[0],xyz[1],z);
8b007a2d 163 //printf("After: first %f %f %f tgl %f center %f %f charge %d\n",GetFirstPointX(),GetFirstPointY(),GetFirstPointZ(),GetTgl(),GetCenterX(),GetCenterY(),GetCharge());
164
165 //printf("First point set %f %f %f\n",xyz[0],xyz[1],z);
d712b5b8 166
167 //Also, set the coordinates of the point where track crosses last padrow:
168 GetCrossingPoint(GetLastRow(),xyz);
169 SetLastPoint(xyz[0],xyz[1],xyz[2]);
8b007a2d 170 //printf("last point %f %f %f\n",xyz[0],xyz[1],xyz[2]);
d712b5b8 171}
172
173void AliL3HoughTrack::SetTrackParameters(Double_t kappa,Double_t phi,Int_t weight)
174{
175
176 fWeight = weight;
177 fMinDist = 100000;
178 SetKappa(kappa);
179 SetPhi0(phi);
b1886074 180 Double_t pt = fabs(BFACT*BField/kappa);
d712b5b8 181 SetPt(pt);
182 Double_t radius = 1/fabs(kappa);
183 SetRadius(radius);
184 SetFirstPoint(0,0,0);
8b007a2d 185 SetPsi(phi); //Psi = Phi when first point is vertex
186 SetR0(0);
d712b5b8 187 Double_t charge = -1.*kappa;
8b007a2d 188 SetCharge((Int_t)copysign(1.,charge));
189
190 Double_t trackPhi0 = GetPsi() + charge*0.5*Pi/fabs(charge);
191 Double_t xc = GetFirstPointX() - GetRadius() * cos(trackPhi0) ;
192 Double_t yc = GetFirstPointY() - GetRadius() * sin(trackPhi0) ;
d712b5b8 193 SetCenterX(xc);
194 SetCenterY(yc);
242c143e 195 SetNHits(1); //just for the trackarray IO
d712b5b8 196 fIsHelix = true;
8b007a2d 197
242c143e 198
d712b5b8 199}
200
201void AliL3HoughTrack::SetLineParameters(Double_t psi,Double_t D,Int_t weight,Int_t *rowrange,Int_t ref_row)
202{
203 //Initialize a track piece, not yet a track
204 //Used in case of straight line transformation
205
206 //Transform line parameters to coordinate system of slice:
207
208 D = D + fTransform->Row2X(ref_row)*cos(psi);
209
210 fDLine = D;
211 fPsiLine = psi;
212 fWeight = weight;
213 SetNHits(weight);
214 SetRowRange(rowrange[0],rowrange[1]);
215 fIsHelix = false;
216
217}
218
219void AliL3HoughTrack::SetBestMCid(Int_t mcid,Double_t min_dist)
220{
221
222 if(min_dist < fMinDist)
223 {
224 fMinDist = min_dist;
225 SetMCid(mcid);
226 }
227
228}
229
230void AliL3HoughTrack::GetLineCrossingPoint(Int_t padrow,Double_t *xy)
231{
232
233
234 if(fIsHelix)
235 {
236 printf("AliL3HoughTrack::GetLineCrossingPoint : Track is not a line\n");
237 return;
238 }
239
240 Double_t xhit = fTransform->Row2X(padrow);
241 Double_t a = -1/tan(fPsiLine);
242 Double_t b = fDLine/sin(fPsiLine);
243
244 Double_t yhit = a*xhit + b;
245 xy[0] = xhit;
246 xy[1] = yhit;
247
248}
249
250/*
251Double_t AliL3HoughTrack::GetCrossingAngle(Int_t padrow)
252{
253 //Calculate the crossing angle between track and given padrow.
254
255 if(!fIsHelix)
256 {
257 printf("AliL3HoughTrack::GetCrossingAngle : Track is not a helix\n");
258 return 0;
259 }
260
261 if(!IsLocal())
262 {
263 printf("Track is not given in local coordinates\n");
264 return 0;
265 }
266
267 Float_t xyz[3];
268 if(!GetCrossingPoint(padrow,xyz))
269 printf("AliL3HoughTrack::GetCrossingPoint : Track does not cross line!!\n");
270
271
272 //Convert center of curvature to local coordinates:
273 //Float_t xyz_coc[3] = {GetCenterX(),GetCenterY(),0};
274 //fTransform->Global2Local(xyz_coc,slice);
275
276 //Take the dot product of the tangent vector of the track, and
277 //vector perpendicular to the padrow.
278
279 Double_t tangent[2];
280 //tangent[1] = (xyz[0] - xyz_coc[0])/GetRadius();
281 //tangent[0] = -1.*(xyz[1] - xyz_coc[1])/GetRadius();
282 tangent[1] = (xyz[0] - GetCenterX())/GetRadius();
283 tangent[0] = -1.*(xyz[1] - GetCenterY())/GetRadius();
284
285 Double_t perp_padrow[2] = {1,0}; //locally in slice
286
287 Double_t cos_beta = fabs(tangent[0]*perp_padrow[0] + tangent[1]*perp_padrow[1]);
288 return acos(cos_beta);
289
290}
291
292Bool_t AliL3HoughTrack::GetCrossingPoint(Int_t padrow,Float_t *xyz)
293{
294 //Assumes the track is given in local coordinates
295
296 if(!fIsHelix)
297 {
298 printf("AliL3HoughTrack::GetCrossingPoint : Track is not a helix\n");
299 return 0;
300 }
301
302
303 if(!IsLocal())
304 {
305 printf("GetCrossingPoint: Track is given on global coordinates\n");
306 return false;
307 }
308
309 Double_t xHit = fTransform->Row2X(padrow);
310
311 //xyz[0] = fTransform->Row2X(padrow);
312 xyz[0] = xHit;
313 Double_t aa = (xHit - GetCenterX())*(xHit - GetCenterX());
314 Double_t r2 = GetRadius()*GetRadius();
315 if(aa > r2)
316 return false;
317
318 Double_t aa2 = sqrt(r2 - aa);
319 Double_t y1 = GetCenterY() + aa2;
320 Double_t y2 = GetCenterY() - aa2;
321 xyz[1] = y1;
322 if(fabs(y2) < fabs(y1)) xyz[1] = y2;
323 xyz[2] = 0; //only consider transverse plane
324
325 return true;
326}
327
328
329Bool_t AliL3HoughTrack::GetCrossingPoint(Int_t slice,Int_t padrow,Float_t *xyz)
330{
331 //Calculate the crossing point in transverse plane of this track and given
332 //padrow (y = a*x + b). Point is given in local coordinates in slice.
333 //Assumes the track is given in global coordinates.
334
335 if(!fIsHelix)
336 {
337 printf("AliL3HoughTrack::GetCrossingPoint : Track is not a helix\n");
338 return 0;
339 }
340
341
342 if(IsLocal())
343 {
344 printf("GetCrossingPoint: Track is given in local coordintes!!!\n");
345 return false;
346 }
347
348 Double_t padrowradii = fTransform->Row2X(padrow);
349
350
351 Float_t rotation_angle = (slice*20)*ToRad;
352
353 Float_t cs,sn;
354 cs = cos(rotation_angle);
355 sn = sin(rotation_angle);
356
357 Double_t a = -1.*cs/sn;
358 Double_t b = padrowradii/sn;
359
360 Double_t ycPrime = GetCenterY() - b ;
361 Double_t aa = ( 1. + a * a ) ;
362 Double_t bb = -2. * ( GetCenterX() + a * ycPrime ) ;
363 Double_t cc = ( GetCenterX() * GetCenterX() + ycPrime * ycPrime - GetRadius() * GetRadius() ) ;
364
365 Double_t racine = bb * bb - 4. * aa * cc ;
366 if ( racine < 0 ) return false ;
367 Double_t rootRacine = sqrt(racine) ;
368
369 Double_t oneOverA = 1./aa;
370//
371// First solution
372//
373 Double_t x1 = 0.5 * oneOverA * ( -1. * bb + rootRacine ) ;
374 Double_t y1 = a * x1 + b ;
375 Double_t r1 = sqrt(x1*x1+y1*y1);
376//
377// Second solution
378//
379 Double_t x2 = 0.5 * oneOverA * ( -1. * bb - rootRacine ) ;
380 Double_t y2 = a * x2 + b ;
381 Double_t r2 = sqrt(x2*x2+y2*y2);
382//
383// Choose close to (0,0)
384//
385 Double_t xHit ;
386 Double_t yHit ;
387 if ( r1 < r2 ) {
388 xHit = x1 ;
389 yHit = y1 ;
390 }
391 else {
392 xHit = x2 ;
393 yHit = y2 ;
394 }
395
396 xyz[0] = xHit;
397 xyz[1] = yHit;
398 xyz[2] = 0;
399
400 fTransform->Global2Local(xyz,slice);
401
402 return true;
403}
404*/