1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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 **************************************************************************/
18 ///////////////////////////////////////////////////////////////////////////////
20 // Time Projection Chamber track hits object //
22 // Origin: Marian Ivanov , GSI Darmstadt
24 // Class for storing simulated AliTPCHits for given track //
25 // -average compression comparing to classical ClonesArray is //
26 // around 5-7 (depending on the required hit precision) //
30 <img src="gif/AliTPCTrackHits.gif">
35 ///////////////////////////////////////////////////////////////////////////////
40 #include "AliTPCTrackHits.h"
42 #include "AliTPCTrackHitsInterfaces.h"
44 ClassImp(AliTPCTrackHits)
45 LClassImp(AliTrackHitsInfo)
46 LClassImp(AliTrackHitsParam)
49 Int_t AliTrackHitsInfo::fgCounter1 =0;
50 Int_t AliTrackHitsInfo::fgCounter2 =0;
51 Int_t AliTrackHitsParam::fgCounter1 =0;
52 Int_t AliTrackHitsParam::fgCounter2 =0;
53 Int_t AliHitInfo::fgCounter1 =0;
54 Int_t AliHitInfo::fgCounter2 =0;
55 Int_t AliTPCTrackHits::fgCounter1 =0;
56 Int_t AliTPCTrackHits::fgCounter2 =0;
57 const Double_t AliTPCTrackHits::fgkPrecision=1e-6; //precision
58 const Double_t AliTPCTrackHits::fgkPrecision2=1e-20; //precision
61 class AliTPCCurrentHit {
62 friend class AliTPCTrackHits;
64 AliTPChit fHit; // - hit in "standard" representation
65 UInt_t fInfoIndex;// - current info pointer
66 UInt_t fParamIndex;// - current param pointer
67 UInt_t fStackIndex; // - current hit stack index
68 Double_t fR; //current Radius
69 Bool_t fStatus; //current status
73 class AliTPCTempHitInfo {
74 friend class AliTPCTrackHits;
76 enum { kStackSize = 100};
78 AliTPCTempHitInfo(const AliTPCTempHitInfo &)
79 {::Fatal("copy ctor","Not implemented\n");}
80 AliTPCTempHitInfo & operator = (const AliTPCTempHitInfo &)
81 {::Fatal("= operator","Not implemented\n");return *this;}
83 void NewParam(Double_t r, Double_t z, Double_t fi, Int_t q);
84 void SetHit(Double_t r, Double_t z, Double_t fi, Int_t q);
85 Double_t * GetPosition(Int_t index){return &fPositionStack[index*3];}
86 void UpdateParam(Double_t maxdelta); //recal
87 void Fit2(Double_t fSumY, Double_t fSumYX, Double_t fSumYX2,
88 Double_t fSumX, Double_t fSumX2, Double_t fSumX3,
89 Double_t fSumX4, Int_t n,
90 Double_t &a, Double_t &b, Double_t &c);
91 void Fit(AliTrackHitsParam * param);
92 Double_t fSumDr; //fSumDr
93 Double_t fSumDr2; //fSumDr2
94 Double_t fSumDr3; // fSumDr3
95 Double_t fSumDr4; //fSumDr4
96 Double_t fSumDFi; //fSumDFi
97 Double_t fSumDFiDr; // fSumDFiDr
98 Double_t fSumDFiDr2;//fSumDFiDr2
99 Double_t fSumDZ; //fSumDZ
100 Double_t fSumDZDr; //fSumDZDr
101 Double_t fSumDZDr2; //fSumDZDr2
102 Double_t fOldR; //previos r
103 Double_t fPositionStack[3*kStackSize]; //position stack
104 UInt_t fQStack[kStackSize]; //Q stack
105 UInt_t fStackIndex; //current stack index
106 UInt_t fInfoIndex; //current track info index
107 UInt_t fParamIndex; //current track parameters index
108 AliTrackHitsInfo * fInfo; //current track info
109 AliTrackHitsParam * fParam; //current track param
113 AliTPCTempHitInfo::AliTPCTempHitInfo()
116 //set to default value
117 fSumDr=fSumDr2=fSumDr3=fSumDr4=
118 fSumDFi=fSumDFiDr=fSumDFiDr2=
119 fSumDZ=fSumDZDr=fSumDZDr2=0;
126 void AliTPCTempHitInfo::NewParam(Double_t r, Double_t z, Double_t fi, Int_t q)
129 //reset stack and sum parameters
130 //store line initial point
131 fSumDr=fSumDr2=fSumDr3=fSumDr4=
132 fSumDFi=fSumDFiDr=fSumDFiDr2=
133 fSumDZ=fSumDZDr=fSumDZDr2=0;
146 void AliTPCTempHitInfo::SetHit(Double_t r, Double_t z, Double_t fi, Int_t q)
149 //add hit to the stack
150 //recalculate new estimete of line parameters
151 Double_t *f = GetPosition(fStackIndex);
155 fQStack[fStackIndex]=q;
156 if (fStackIndex==0) return;
157 Double_t dr = (r-fParam->fR);
158 if (TMath::Abs(dr)<AliTPCTrackHits::fgkPrecision) dr =AliTPCTrackHits::fgkPrecision;
159 Double_t dfi = fi-fParam->fFi;
160 Double_t dz = z -fParam->fZ;
162 Double_t dr3 =dr2*dr;
163 Double_t dr4 =dr3*dr;
175 //update fit parameters
177 Double_t det = fSumDr2*fSumDr4-fSumDr3*fSumDr3;
178 if (TMath::Abs(det)<AliTPCTrackHits::fgkPrecision2) return;
179 if ( ( fStackIndex>1 ) ){
180 fParam->fAn = (fSumDr4*fSumDFiDr-fSumDr3*fSumDFiDr2)/det;
181 fParam->fAd = (fSumDr2*fSumDFiDr2-fSumDr3*fSumDFiDr)/det;
184 fParam->fAn = fSumDFiDr/fSumDr2;
185 if ( ( fStackIndex>1 ) ){
186 fParam->fTheta = (fSumDr4*fSumDZDr-fSumDr3*fSumDZDr2)/det;
187 fParam->fThetaD= (fSumDr2*fSumDZDr2-fSumDr3*fSumDZDr)/det;
190 fParam->fTheta = fSumDZDr/fSumDr2;
194 void AliTPCTempHitInfo::UpdateParam(Double_t maxdelta)
196 //recalc parameters not fixing origin point
200 Fit2(fSumDFi, fSumDFiDr, fSumDFiDr2, fSumDr,fSumDr2,fSumDr3,fSumDr4,
202 if (TMath::Abs(a)<maxdelta){
203 fParam->fFi +=a/fParam->fR;
207 Fit2(fSumDZ, fSumDZDr, fSumDZDr2, fSumDr,fSumDr2,fSumDr3,fSumDr4,
208 fStackIndex, a,b,c) ;
209 if (TMath::Abs(a)<maxdelta){
217 void AliTPCTempHitInfo::Fit2(Double_t fSumY, Double_t fSumYX, Double_t fSumYX2,
218 Double_t fSumX, Double_t fSumX2, Double_t fSumX3,
219 Double_t fSumX4, Int_t n,
220 Double_t &a, Double_t &b, Double_t &c)
222 //fit of second order
224 n* (fSumX2*fSumX4-fSumX3*fSumX3) -
225 fSumX* (fSumX*fSumX4-fSumX3*fSumX2)+
226 fSumX2* (fSumX*fSumX3-fSumX2*fSumX2);
228 if (TMath::Abs(det)> AliTPCTrackHits::fgkPrecision) {
230 (fSumY * (fSumX2*fSumX4-fSumX3*fSumX3)-
231 fSumX *(fSumYX*fSumX4-fSumYX2*fSumX3)+
232 fSumX2*(fSumYX*fSumX3-fSumYX2*fSumX2))/det;
234 (n*(fSumYX*fSumX4-fSumX3*fSumYX2)-
235 fSumY*(fSumX*fSumX4-fSumX3*fSumX2)+
236 fSumX2*(fSumX*fSumYX2-fSumYX*fSumX2))/det;
238 (n*(fSumX2*fSumYX2-fSumYX*fSumX3)-
239 fSumX*(fSumX*fSumYX2-fSumYX*fSumX2)+
240 fSumY*(fSumX*fSumX3-fSumX2*fSumX2))/det;
244 void AliTPCTempHitInfo::Fit(AliTrackHitsParam * param)
246 // fit fixing first and the last point
247 //result stored in new param
248 Double_t dx2 = (GetPosition(fStackIndex))[0]-fParam->fR;
249 Double_t det = fSumDr4+dx2*fSumDr2-2*dx2*fSumDr3;
250 if ( (TMath::Abs(det)> AliTPCTrackHits::fgkPrecision) &&
251 ((TMath::Abs(dx2)> AliTPCTrackHits::fgkPrecision))){
252 Double_t dfi2 = (GetPosition(fStackIndex))[1]-fParam->fFi;
253 param->fAd = (fSumDFiDr2+dfi2*fSumDr-dx2*fSumDFiDr-dfi2*fSumDr3/dx2)/det;
254 param->fAn = (dfi2-param->fAd*dx2*dx2)/dx2;
256 Double_t dz2 = (GetPosition(fStackIndex))[1]-fParam->fZ;
257 param->fTheta = (fSumDZDr2+dz2*fSumDr-dx2*fSumDZDr-dz2*fSumDr3/dx2)/det;
258 param->fTheta = (dz2-param->fAd*dx2*dx2)/dx2;
263 //______________________________________________________________________
264 AliTrackHitsInfo::AliTrackHitsInfo() :
270 // Default constructor
276 //______________________________________________________________________
277 AliTrackHitsParam::AliTrackHitsParam() :
287 // Default constructor
294 AliTPCTrackHits::AliTPCTrackHits()
297 //default constructor
299 const Float_t kHitPrecision=0.002; //default precision for hit position in cm
300 const Float_t kStep =0.003; //30 mum step
301 const UShort_t kMaxDistance =100; //maximum distance 100
303 fPrecision=kHitPrecision; //precision in cm
304 fStep = kStep; //step size
305 fMaxDistance = kMaxDistance; //maximum distance
307 fTrackHitsInfo = new AliObjectArray("AliTrackHitsInfo");
308 fTrackHitsParam = new AliObjectArray("AliTrackHitsParam");
309 fHitsPosAndQ = new TArrayOfArrayVStack("AliHitInfo");
310 fCurrentHit = new AliTPCCurrentHit;
316 AliTPCTrackHits::AliTPCTrackHits(const AliTPCTrackHits& r) : TObject(r)
320 AliTPCTrackHits &AliTPCTrackHits::operator=(const AliTPCTrackHits& /* r */)
326 AliTPCTrackHits::~AliTPCTrackHits()
331 if (fTrackHitsInfo) delete fTrackHitsInfo;
332 if (fTrackHitsParam) delete fTrackHitsParam;
333 if (fHitsPosAndQ) delete fHitsPosAndQ;
334 if (fCurrentHit) delete fCurrentHit;
335 if (fTempInfo) delete fTempInfo;
339 void AliTPCTrackHits::Clear()
343 fTrackHitsInfo->Clear();
344 fTrackHitsParam->Clear();
345 //fTrackHitsInfo->Resize(0);
346 //fTrackHitsParam->Resize(0);
347 fHitsPosAndQ->Clear();
356 void AliTPCTrackHits::AddHitKartez(Int_t volumeID, Int_t trackID, Double_t x,
357 Double_t y, Double_t z,Int_t q)
359 //add hits (cartesian)
360 Double_t r = TMath::Sqrt(x*x+y*y);
361 Double_t fi = TMath::ACos(x/r);
363 AddHit(volumeID,trackID,r,z,fi,q);
366 void AliTPCTrackHits::AddHit(Int_t volumeID, Int_t trackID,
367 Double_t r, Double_t z, Double_t fi, Int_t q)
371 if (!fTempInfo) { //initialsation of track
372 fTempInfo = new AliTPCTempHitInfo;
374 if (fTrackHitsInfo->GetCapacity()<10) fTrackHitsInfo->Reserve(10);
375 fTrackHitsInfo->Resize(1);
376 fTempInfo->fInfoIndex =0;
377 if (fTrackHitsParam->GetCapacity()<100) fTrackHitsParam->Reserve(100);
378 fTrackHitsParam->Resize(1);
381 (AliTrackHitsInfo*) (fTrackHitsInfo->At(0));
382 fTempInfo->fInfo->fVolumeID = volumeID;
383 fTempInfo->fInfo->fTrackID = trackID;
384 fTempInfo->fInfo->fHitParamIndex =0;
385 fTempInfo->fInfoIndex = 0;
388 (AliTrackHitsParam*) (fTrackHitsParam->At(0));
389 fTempInfo->fParamIndex = 0;
390 fTempInfo->NewParam(r,z,fi,q);
394 Int_t size = fHitsPosAndQ->GetSize();
395 if (size>(Int_t)fTempInfo->fParamIndex) {
396 fTempInfo->fParamIndex++;
397 if (fTempInfo->fParamIndex+1>fTrackHitsParam->GetSize())
398 fTrackHitsParam->Resize(fTempInfo->fParamIndex+1);
400 (AliTrackHitsParam*) (fTrackHitsParam->At(fTempInfo->fParamIndex));
401 fTempInfo->NewParam(r,z,fi,q);
406 // if new volume or new trackID
407 if ( (volumeID!=fTempInfo->fInfo->fVolumeID) ||
408 (trackID!=fTempInfo->fInfo->fTrackID)){
411 FlushHitStack(kTRUE);
413 fTempInfo->fInfoIndex++;
414 if (fTempInfo->fInfoIndex+1>fTrackHitsInfo->GetSize())
415 fTrackHitsInfo->Resize(fTempInfo->fInfoIndex+1);
417 (AliTrackHitsInfo*) (fTrackHitsInfo->At(fTempInfo->fInfoIndex));
418 fTempInfo->fInfo->fVolumeID = volumeID;
419 fTempInfo->fInfo->fTrackID = trackID;
420 fTempInfo->fInfo->fHitParamIndex =fTempInfo->fParamIndex+1;
421 // FlushHitStack(kTRUE);
423 fTempInfo->fParamIndex++;
424 if (fTempInfo->fParamIndex+1>fTrackHitsParam->GetSize())
425 fTrackHitsParam->Resize(fTempInfo->fParamIndex+1);
427 (AliTrackHitsParam*) (fTrackHitsParam->At(fTempInfo->fParamIndex));
428 fTempInfo->NewParam(r,z,fi,q);
432 //calculate current fit precission to next point
433 AliTrackHitsParam ¶m = *(fTempInfo->fParam);
437 Double_t dr,dz,dfi,ddz,ddfi;
439 dr=dz=dfi=ddz=ddfi=0;
440 drhit = r-fTempInfo->fOldR;
442 //Double_t dfi2 = param.fAn+2*param.fAd*(r-param.fR);
443 Double_t dfi2 = param.fAn;
444 dfi2*=dfi2*fTempInfo->fOldR*fTempInfo->fOldR;
445 //Double_t ddz2 = param.fTheta+2*param.fThetaD*(r-param.fR);
446 Double_t ddz2 = param.fTheta;
448 ratio = TMath::Sqrt(1.+ dfi2+ ddz2);
453 dl = (TMath::Abs(drhit*ratio/fStep)<32000) ? fStep * Short_t(TMath::Nint(drhit*ratio/fStep)):0;
454 ddl = dl - drhit*ratio;
455 fTempInfo->fOldR += dl/ratio;
457 if (fTempInfo->fStackIndex>2){
461 ddz = dr*param.fTheta+dr*dr*param.fThetaD-dz;
462 ddfi= dr*param.fAn+dr*dr*param.fAd-dfi;
463 dd = TMath::Sqrt(ddz*ddz+r*r*ddfi*ddfi+ddl*ddl);
467 if ( ( (dd*1.25>fPrecision) ) ||
468 (fTempInfo->fStackIndex+4>fTempInfo->kStackSize) ||
469 (TMath::Abs(dl/fStep)>fMaxDistance) )
472 fTempInfo->fStackIndex++;
473 fTempInfo->SetHit(r,z,fi,q);
476 //if parameter changed
477 if (FlushHitStack(kFALSE)){ //if full buffer flushed
478 fTempInfo->fParamIndex++;
479 if (fTempInfo->fParamIndex+1>fTrackHitsParam->GetSize())
480 fTrackHitsParam->Resize(fTempInfo->fParamIndex+1);
482 (AliTrackHitsParam*) (fTrackHitsParam->At(fTempInfo->fParamIndex));
483 fTempInfo->NewParam(r,z,fi,q);
486 fTempInfo->fStackIndex++;
487 fTempInfo->SetHit(r,z,fi,q);
491 Bool_t AliTPCTrackHits::FlushHitStack(Bool_t force)
494 //write fHitsPosAndQ information from the stack to te arrays
495 if (!fTempInfo) return kFALSE;
496 Int_t size = fHitsPosAndQ->GetSize();
498 if ( (size>0)&&(size!=(Int_t)fTempInfo->fParamIndex)) return kFALSE;
500 if (fHitsPosAndQ->Push(fTempInfo->fStackIndex+1)!=fTempInfo->fParamIndex){
501 cout<<"internal error - contact MI\n";
506 AliTrackHitsParam & param = *(fTempInfo->fParam);
507 //recalculate track parameter not fixing first point
508 fTempInfo->UpdateParam(fStep/4.);
509 //fTempInfo->Fit(fTempInfo->fParam); //- fixing the first and the last point
511 Double_t oldr = param.fR;
512 //cout<<"C3"<<fTempInfo->fStackIndex<<"\n"<<flush;
515 for (i=0; i <= fTempInfo->fStackIndex; i++){
516 Double_t * position = fTempInfo->GetPosition(i);
517 Double_t dr = position[0]-oldr;
520 //Double_t dfi2 = param.fAn+2*param.fAd*(position[0]-param.fR);
521 Double_t dfi2 = param.fAn;
522 dfi2*=dfi2*oldr*oldr;
523 //Double_t ddz2 = param.fTheta+2*param.fThetaD*(position[0]-param.fR);
524 Double_t ddz2 = param.fTheta;
526 ratio = TMath::Sqrt(1.+ dfi2+ ddz2);
529 Double_t dl = (TMath::Abs(dr*ratio/fStep)<32000) ? fStep*(Short_t)TMath::Nint(dr*ratio/fStep):0;
532 //calculate precission
533 AliTrackHitsParam ¶m = *(fTempInfo->fParam);
535 Double_t dr1= position[0]-param.fR;
536 Double_t dz = position[1]-param.fZ;
538 Double_t dfi = position[2]-param.fFi;
539 //extrapolated deltas
540 Double_t dr2 = oldr-param.fR;
541 Double_t ddr = dr2-dr1;
542 Double_t ddz = dr2*param.fTheta+dr2*dr2*param.fThetaD-dz;
543 Double_t ddfi= dr2*param.fAn+dr2*dr2*param.fAd-dfi;
544 dd = TMath::Sqrt(ddz*ddz+oldr*oldr*ddfi*ddfi+ddr*ddr);
546 if ( (dd>fPrecision) ){
552 Double_t ddz = dr2*param.fTheta+dr2*dr2*param.fThetaD-dz;
553 Double_t ddfi= dr2*param.fAn+dr2*dr2*param.fAd-dfi;
555 dd = TMath::Sqrt(ddz*ddz+oldr*oldr*ddfi*ddfi+ddr*ddr);
561 info = (AliHitInfo*)(fHitsPosAndQ->At(fTempInfo->fParamIndex,i));
562 info->fHitDistance = (TMath::Abs(dl/fStep)<32000) ?Short_t(TMath::Nint(dl/fStep)):0;
563 info->fCharge = Short_t(fTempInfo->fQStack[i]);
566 cout<<" "<<fTempInfo->fStackIndex<<" \t";
568 cout<<position[0]<<"\t";
569 cout<<position[1]<<"\t";
570 cout<<position[2]<<"\t";
571 cout<<param.fAn<<"\t";
572 cout<<param.fTheta<<"\t";
573 cout<<dr1<<"\t"<<ddr<<"\t"<<ddz<<"\t"<<ddfi<<"\t"<<dd<<"\n"<<flush;
577 if (i<=fTempInfo->fStackIndex){ //if previous iteration not succesfull
578 fHitsPosAndQ->Resize(fTempInfo->fParamIndex,i);
580 fTempInfo->fParamIndex++;
581 if (fTempInfo->fParamIndex+1>fTrackHitsParam->GetSize())
582 fTrackHitsParam->Resize(fTempInfo->fParamIndex+1);
584 (AliTrackHitsParam*) (fTrackHitsParam->At(fTempInfo->fParamIndex));
585 Double_t * p = fTempInfo->GetPosition(i);
586 UInt_t index2 = fTempInfo->fStackIndex;
587 fTempInfo->NewParam(p[0],p[1],p[2],fTempInfo->fQStack[i]);
588 if (i+1<=index2) FlushHitStack2(i+1,index2);
590 if (force) return FlushHitStack(kTRUE);
597 void AliTPCTrackHits::FlushHitStack2(Int_t index1, Int_t index2)
600 // second iteration flush stack
601 // call only for hits where first iteration were not succesfully interpolated
602 Double_t * positionstack = new Double_t[3*(index2-index1+1)];
603 UInt_t * qstack = new UInt_t[index2-index1+1];
604 memcpy(positionstack, &fTempInfo->fPositionStack[3*index1],
605 (3*(index2-index1+1))*sizeof(Double_t));
606 memcpy(qstack, &fTempInfo->fQStack[index1],(index2-index1+1)*sizeof(UInt_t));
607 Double_t *p = positionstack;
608 for (Int_t j=0; j<=index2-index1;j++){
609 fTempInfo->fStackIndex++;
610 fTempInfo->SetHit(p[3*j+0],p[3*j+1],p[3*j+2],qstack[j]);
612 delete []positionstack;
624 Bool_t AliTPCTrackHits::First()
627 //set Current hit for the first hit
629 AliTrackHitsInfo *info = (AliTrackHitsInfo *)fTrackHitsInfo->At(0);
630 AliTrackHitsParam *param = (AliTrackHitsParam *)fTrackHitsParam->At(0);
631 AliHitInfo * hinfo = (AliHitInfo *)fHitsPosAndQ->At(0,0);
633 if (!(info) || !(param) || !(hinfo) ) {
634 fCurrentHit->fStatus = kFALSE;
638 fCurrentHit->fInfoIndex = 0;
639 fCurrentHit->fParamIndex = 0;
640 fCurrentHit->fStackIndex = 0;
642 fCurrentHit->fHit.fSector = info->fVolumeID;
643 fCurrentHit->fHit.SetTrack(info->fTrackID);
644 fCurrentHit->fHit.SetX(param->fR*TMath::Cos(param->fFi));
645 fCurrentHit->fHit.SetY(param->fR*TMath::Sin(param->fFi));
646 fCurrentHit->fHit.SetZ(param->fZ);
647 fCurrentHit->fHit.fQ = hinfo->fCharge;
649 fCurrentHit->fR = param->fR;
651 return fCurrentHit->fStatus = kTRUE;
656 Bool_t AliTPCTrackHits::Next()
660 if (!(fCurrentHit->fStatus))
663 fCurrentHit->fStackIndex++;
664 AliHitInfo * hinfo = (AliHitInfo *)fHitsPosAndQ->At(fCurrentHit->fParamIndex,
665 fCurrentHit->fStackIndex);
666 AliTrackHitsInfo *info = (AliTrackHitsInfo *)fTrackHitsInfo->At(fCurrentHit->fInfoIndex);
667 AliTrackHitsParam *param = (AliTrackHitsParam *)fTrackHitsParam->At(fCurrentHit->fParamIndex);
670 hinfo = (AliHitInfo *)fHitsPosAndQ->At(fCurrentHit->fParamIndex+1, 0);
672 return fCurrentHit->fStatus = kFALSE;
674 fCurrentHit->fParamIndex++;
675 fCurrentHit->fStackIndex = 0;
676 param = (AliTrackHitsParam *)fTrackHitsParam->At(fCurrentHit->fParamIndex);
678 return fCurrentHit->fStatus = kFALSE;
679 fCurrentHit->fR = param->fR;
681 if ((fCurrentHit->fInfoIndex+1<fTrackHitsInfo->GetSize())
682 &&((info+1)->fHitParamIndex<=fCurrentHit->fParamIndex)){
683 fCurrentHit->fInfoIndex++;
684 info = (AliTrackHitsInfo *)fTrackHitsInfo->At(fCurrentHit->fInfoIndex);
686 return fCurrentHit->fStatus = kFALSE;
687 fCurrentHit->fHit.fSector = info->fVolumeID;
688 fCurrentHit->fHit.SetTrack(info->fTrackID);
694 // Double_t dfi2 = param->fAn+2*param->fAd*(fCurrentHit->fR-param->fR);
695 Double_t dfi2 = param->fAn;
696 dfi2*=dfi2*fCurrentHit->fR*fCurrentHit->fR;
697 // Double_t ddz2 = param->fTheta+2*param->fThetaD*(fCurrentHit->fR-param->fR);
698 Double_t ddz2 = param->fTheta;
700 ratio = TMath::Sqrt(1.+ dfi2+ ddz2);
703 fCurrentHit->fHit.fQ = hinfo->fCharge;
704 fCurrentHit->fR += fStep*hinfo->fHitDistance/ratio;
705 Double_t dR = fCurrentHit->fR - param->fR;
707 Double_t fi = param->fFi + (param->fAn*dR+param->fAd*dR*dR);
708 Double_t z = param->fZ + (param->fTheta*dR+param->fThetaD*dR*dR);
710 fCurrentHit->fHit.SetX(fCurrentHit->fR*TMath::Cos(fi));
711 fCurrentHit->fHit.SetY(fCurrentHit->fR*TMath::Sin(fi));
712 fCurrentHit->fHit.SetZ(z);
717 AliTPChit * AliTPCTrackHits::GetHit() const
720 return (fCurrentHit->fStatus)? &fCurrentHit->fHit:0;
721 //return &fCurrentHit->fHit;
727 Bool_t AliTPCTrackHits::Next(Int_t id)
731 if (!(fCurrentHit->fStatus))
734 // fCurrentHit->fStackIndex++;
735 AliHitInfo * hinfo = (AliHitInfo *)fHitsPosAndQ->At(fCurrentHit->fParamIndex,
736 fCurrentHit->fStackIndex);
737 AliTrackHitsInfo *info = (AliTrackHitsInfo *)fTrackHitsInfo->At(fCurrentHit->fInfoIndex);
739 fCurrentHit->fStatus = kFALSE;
742 AliTrackHitsParam *param = (AliTrackHitsParam *)fTrackHitsParam->At(fCurrentHit->fParamIndex);
744 if ( (id>=0) && (info!=0) && (info->fVolumeID!=id)){
745 fCurrentHit->fInfoIndex++;
746 info = (AliTrackHitsInfo *)fTrackHitsInfo->At(fCurrentHit->fInfoIndex);
748 fCurrentHit->fStatus = kFALSE;
751 fCurrentHit->fParamIndex = info->fHitParamIndex;
752 param = (AliTrackHitsParam *)fTrackHitsParam->At(fCurrentHit->fParamIndex);
753 fCurrentHit->fStackIndex =0;
754 fCurrentHit->fR = param->fR;
758 fCurrentHit->fStatus = kFALSE;
762 hinfo = (AliHitInfo *)fHitsPosAndQ->At(fCurrentHit->fParamIndex+1, 0);
764 fCurrentHit->fStatus = kFALSE;
768 fCurrentHit->fParamIndex++;
769 fCurrentHit->fStackIndex = 0;
770 param = (AliTrackHitsParam *)fTrackHitsParam->At(fCurrentHit->fParamIndex);
772 fCurrentHit->fStatus = kFALSE;
775 fCurrentHit->fR = param->fR;
777 if ((fCurrentHit->fInfoIndex+1<fTrackHitsInfo->GetSize())
778 &&((info+1)->fHitParamIndex<=fCurrentHit->fParamIndex)){
779 fCurrentHit->fInfoIndex++;
780 info = (AliTrackHitsInfo *)fTrackHitsInfo->At(fCurrentHit->fInfoIndex);
782 fCurrentHit->fStatus = kFALSE;
785 if ( (id>=0) && (info!=0) && (info->fVolumeID!=id)){
788 fCurrentHit->fHit.fSector = info->fVolumeID;
789 fCurrentHit->fHit.SetTrack(info->fTrackID);
795 // Double_t dfi2 = param->fAn+2*param->fAd*(fCurrentHit->fR-param->fR);
796 Double_t dfi2 = param->fAn;
797 dfi2*=dfi2*fCurrentHit->fR*fCurrentHit->fR;
798 // Double_t ddz2 = param->fTheta+2*param->fThetaD*(fCurrentHit->fR-param->fR);
799 Double_t ddz2 = param->fTheta;
801 ratio = TMath::Sqrt(1.+ dfi2+ ddz2);
804 fCurrentHit->fHit.fQ = hinfo->fCharge;
805 fCurrentHit->fR += fStep*hinfo->fHitDistance/ratio;
806 Double_t dR = fCurrentHit->fR - param->fR;
808 Double_t fi = param->fFi + (param->fAn*dR+param->fAd*dR*dR);
809 Double_t z = param->fZ + (param->fTheta*dR+param->fThetaD*dR*dR);
811 fCurrentHit->fHit.SetX(fCurrentHit->fR*TMath::Cos(fi));
812 fCurrentHit->fHit.SetY(fCurrentHit->fR*TMath::Sin(fi));
813 fCurrentHit->fHit.SetZ(z);
814 fCurrentHit->fHit.fSector = info->fVolumeID;
815 fCurrentHit->fHit.SetTrack(info->fTrackID);
817 fCurrentHit->fStatus = kTRUE;
818 fCurrentHit->fStackIndex++;
823 AliTrackHitsParam * AliTPCTrackHits::GetParam()
826 return (fCurrentHit->fStatus)? (AliTrackHitsParam *)fTrackHitsParam->At(fCurrentHit->fParamIndex) :0;
829 AliHitInfo * AliTPCTrackHits::GetHitInfo()
832 return (fCurrentHit->fStatus)?
833 (AliHitInfo *)fHitsPosAndQ->At(fCurrentHit->fParamIndex,fCurrentHit->fStackIndex) :0;