EVE/Alieve/AliEveTrackFitter.cxx

   1 // $Id$
   2 // Main authors: Matevz Tadel & Alja Mrak-Tadel: 2006, 2007
   3
   4 /**************************************************************************
   5  * Copyright(c) 1998-2008, ALICE Experiment at CERN, all rights reserved. *
   6  * See http://aliceinfo.cern.ch/Offline/AliRoot/License.html for          *
   7  * full copyright notice.                                                 *
   8  **************************************************************************/
   9
  10 #include "AliEveTrackFitter.h"
  11
  12 #include "TCanvas.h"
  13 #include "TGraph.h"
  14 #include "TGraphErrors.h"
  15
  16 #include "AliCluster.h"
  17 #include "AliRieman.h"
  18 #include "AliExternalTrackParam.h"
  19
  20 #include <TEveTrack.h>
  21 #include <TEveTrackPropagator.h>
  22 #include <TEveVSDStructs.h>
  23 #include <TEveManager.h>
  24
  25
  26 //______________________________________________________________________
  27 // AliEveTrackFitter
  28 //
  29 // AliEveTrackFitter is an interface to helix fit. It creates a set of
  30 // points, listening to signal PointCtrlClicked() of any
  31 // TEvePointSet. Via editor it fits selected points and creates a
  32 // reconstructed track.
  33 //
  34
  35 ClassImp(AliEveTrackFitter)
  36
  37 AliEveTrackFitter::AliEveTrackFitter(const Text_t* name, Int_t n_points) :
  38     TEvePointSet(name, n_points),
  39
  40     fGraphSelected(0),
  41     fGraphFitted(0),
  42
  43     fRieman(0),
  44     fConnected(kFALSE),
  45     fTrackList(0)
  46 {
  47   // Constructor.
  48
  49   SetMarkerColor(3);
  50   SetOwnIds(kFALSE);
  51
  52   fGraphSelected = new TGraph();
  53   fGraphSelected->SetName("Selected points");
  54   fGraphSelected->SetMarkerColor(4);
  55   fGraphSelected->SetMarkerStyle(4);
  56   fGraphSelected->SetMarkerSize(2);
  57
  58   fGraphFitted = new TGraphErrors();
  59   fGraphFitted->SetName("Fitted points");
  60   fGraphFitted->SetMarkerColor(2);
  61
  62   fTrackList = new TEveTrackList("Tracks");
  63   fTrackList->SetLineWidth(2);
  64   fTrackList->SetLineColor(8);
  65   fTrackList->IncDenyDestroy();
  66   fTrackList->GetPropagator()->SetEditPathMarks(kTRUE);
  67   gEve->AddElement(fTrackList, this);
  68   UpdateItems();
  69 }
  70
  71 AliEveTrackFitter::~AliEveTrackFitter()
  72 {
  73   // Destructor.
  74
  75   if(fRieman) delete fRieman;
  76   fTrackList->DecDenyDestroy();
  77   delete fTrackList;
  78 }
  79
  80 /**************************************************************************/
  81 void AliEveTrackFitter::DestroyElements()
  82 {
  83   // Virtual method of base class TEveElement.
  84   // It preserves track list to have coomon track propagator attributes.
  85
  86   TEveElement::DestroyElements();
  87   gEve->AddElement(fTrackList, this);
  88   fTrackList->DestroyElements();
  89   UpdateItems();
  90 }
  91
  92 /**************************************************************************/
  93 void AliEveTrackFitter::Start()
  94 {
  95   // Start selection of points.
  96
  97   Reset();
  98   if(fConnected == kFALSE)
  99   {
 100     TQObject::Connect("TEvePointSet", "PointCtrlClicked(TEvePointSet*,Int_t)",
 101                       "AliEveTrackFitter", this, "AddFitPoint(TEvePointSet*,Int_t)");
 102
 103     fConnected = kTRUE;
 104   }
 105 }
 106
 107 void AliEveTrackFitter::Stop()
 108 {
 109   // Stop selection of points.
 110
 111   if(fConnected)
 112   {
 113     TQObject::Disconnect("TEvePointSet", "AddFitPoint(TEvePointSet*,Int_t)");
 114     fConnected = kFALSE;
 115   }
 116 }
 117
 118 /**************************************************************************/
 119
 120 void AliEveTrackFitter::AddFitPoint(TEvePointSet* ps, Int_t n)
 121 {
 122   // Add/remove given point depending if exists in the fMapPS.
 123
 124   Float_t x, y, z;
 125
 126   std::map<Point_t, Int_t>::iterator g = fMapPS.find(Point_t(ps, n));
 127   if(g != fMapPS.end())
 128   {
 129     Int_t idx = g->second;
 130     if(idx != fLastPoint)
 131     {
 132       GetPoint(fLastPoint, x, y, z);
 133       SetPoint(idx, x, y, z);
 134     }
 135     fMapPS.erase(g);
 136     fLastPoint--;
 137   }
 138   else
 139   {
 140     fMapPS[Point_t(ps, n)] = Size();
 141     ps->GetPoint(n, x, y, z);
 142     SetNextPoint(x, y, z);
 143     SetPointId(ps->GetPointId(n));
 144   }
 145   ResetBBox();
 146   ElementChanged(kTRUE, kTRUE);
 147 }
 148
 149 /**************************************************************************/
 150
 151 void AliEveTrackFitter::FitTrack()
 152 {
 153   // Fit selected points with AliRieman fitter.
 154
 155   using namespace TMath;
 156
 157   if(fRieman) delete fRieman;
 158   fRieman = new AliRieman(Size());
 159
 160   Float_t x, y, z;
 161   Int_t alphaIdx = 0;
 162   GetPoint(alphaIdx, x, y, z);
 163   Float_t minR2=x*x + y*y;
 164   for (Int_t i=1; i<=fLastPoint; i++)
 165   {
 166     GetPoint(i, x, y, z);
 167     Float_t cR2 = x*x + y*y;
 168     if ( minR2 > cR2 )
 169     {
 170       minR2 = cR2;
 171       alphaIdx = i;
 172     }
 173   }
 174   GetPoint(alphaIdx, x, y, z);
 175   fAlpha = ATan2(y, x);
 176   Float_t sin = Sin(-fAlpha);
 177   Float_t cos = Cos(-fAlpha);
 178   for (Int_t i=0; i<=fLastPoint; i++) {
 179     GetPoint(i, x, y, z);
 180     fRieman->AddPoint(cos*x - sin*y, cos*y + sin*x, z, 1, 1);
 181   }
 182   fRieman->Update();
 183
 184   Double_t r = Sqrt(minR2);
 185   Double_t param[5];
 186   Double_t cov[15];
 187   fRieman->GetExternalParameters(r, param, cov);
 188   // curvature to pt
 189   param[4] /= TEveTrackPropagator::fgDefMagField*TEveTrackPropagator::fgkB2C;
 190   // sign in tang
 191   if(param[4] < 0) param[3] *= -1;
 192   AliExternalTrackParam trackParam(r, fAlpha, param, cov);
 193   trackParam.Print();
 194
 195   // make track
 196   Double_t AliEveV0[3];
 197   trackParam.GetXYZAt(r, TEveTrackPropagator::fgDefMagField, AliEveV0);
 198   Double_t P0[3];
 199   trackParam.GetPxPyPzAt(r, TEveTrackPropagator::fgDefMagField, P0);
 200   TEveRecTrack rc;
 201   rc.fV.Set(AliEveV0);
 202   rc.fP.Set(P0);
 203   rc.fSign = trackParam.Charge();
 204
 205   TEveTrack* track = new TEveTrack(&rc, fTrackList->GetPropagator());
 206   track->SetName(Form("track %f", fAlpha));
 207   TEvePathMark* pm = new TEvePathMark(TEvePathMark::kDaughter);
 208   for(Int_t i=0; i==fLastPoint; i++)
 209   {
 210     GetPoint(i, x, y, z);
 211     pm->fV.Set(x, y, z);
 212     pm->fP.Set(P0);
 213     track->AddPathMark(pm);
 214   }
 215   track->MakeTrack();
 216   track->SetAttLineAttMarker(fTrackList);
 217   gEve->AddElement(track, fTrackList);
 218 }
 219
 220
 221 void AliEveTrackFitter::Reset(Int_t n, Int_t ids)
 222 {
 223   // Reset selection.
 224
 225   if(fRieman) fRieman->Reset();
 226   TEvePointSet::Reset(n, ids);
 227   fMapPS.clear();
 228 }
 229
 230 /**************************************************************************/
 231 void AliEveTrackFitter::DrawRiemanGraph()
 232 {
 233   // Draw graph of rieman fit.
 234
 235    static const TEveException eH("AliEveTrackFitter::DrawRiemanGraph ");
 236
 237   if(fRieman == 0)
 238     throw(eH + "fitter not set.");
 239
 240   Int_t nR = fRieman->GetN();
 241   fGraphSelected->Set(nR);
 242   fGraphFitted->Set(nR);
 243
 244   Double_t* x =  fRieman->GetX();
 245   Double_t* y =  fRieman->GetY();
 246   Double_t* sy =  fRieman->GetSy();
 247   for (Int_t i=0; i<nR; i++)
 248   {
 249     fGraphSelected->SetPoint(i, x[i], y[i]);
 250     fGraphFitted->SetPoint(i, x[i], fRieman->GetYat(x[i]));
 251     fGraphFitted->SetPointError(i, 0.1, sy[i]);
 252   }
 253
 254   if (gPad) gPad->Clear();
 255   fGraphSelected->Draw("AP");
 256   fGraphFitted->Draw("SAME P");
 257   gPad->GetCanvas()->SetTitle(Form("AliRieman alpha: %f", fAlpha));
 258   gPad->Modified();
 259   gPad->Update();
 260 }