Record changes.

[u/mrichter/AliRoot.git] / STEER / AliTracker.cxx

diff --git a/STEER/AliTracker.cxx b/STEER/AliTracker.cxx
index 0322e99b2d22d3e684c7d9451efd8bb93ccca7d9..e0262c5125fa01f54e600624bc7c7b7ee81cc40d 100644 (file)
--- a/STEER/AliTracker.cxx
+++ b/STEER/AliTracker.cxx
@@ -23,17 +23,19 @@
 #include <TClass.h>
 #include <TMath.h>
 
+#include "AliMagF.h"
 #include "AliTracker.h"
 #include "AliCluster.h"
 #include "AliKalmanTrack.h"
 
 Bool_t AliTracker::fgUniformField=kTRUE;
-Double_t AliTracker::fgBz=0.;
+Double_t AliTracker::fgBz=kAlmost0Field;
 const AliMagF *AliTracker::fgkFieldMap=0;
 
 ClassImp(AliTracker)
 
 AliTracker::AliTracker():
+  TObject(),
   fX(0),
   fY(0),
   fZ(0),
@@ -47,19 +49,42 @@ AliTracker::AliTracker():
   if (!fgkFieldMap) AliWarning("Field map is not set. Call AliTracker::SetFieldMap before creating a tracker!");
 }
 
+//__________________________________________________________________________
+AliTracker::AliTracker(const AliTracker &atr):
+  TObject(atr),
+  fX(atr.fX),
+  fY(atr.fY),
+  fZ(atr.fZ),
+  fSigmaX(atr.fSigmaX),
+  fSigmaY(atr.fSigmaY),
+  fSigmaZ(atr.fSigmaZ)
+{
+  //--------------------------------------------------------------------
+  // The default constructor.
+  //--------------------------------------------------------------------
+  if (!fgkFieldMap) AliWarning("Field map is not set. Call AliTracker::SetFieldMap before creating a tracker!");
+}
+
+//__________________________________________________________________________
 void AliTracker::SetFieldMap(const AliMagF* map, Bool_t uni) {
   //--------------------------------------------------------------------
   //This passes the field map to the reconstruction.
   //--------------------------------------------------------------------
   if (map==0) AliFatalClass("Can't access the field map !");
 
+  if (fgkFieldMap) {
+     AliWarningClass("The magnetic field map has been already set !");
+     return;
+  }
+
   fgUniformField=uni;
   fgkFieldMap=map;
 
   //Float_t r[3]={0.,0.,0.},b[3]; map->Field(r,b);
-  //fgBz= - b[2];
+  //Double_t bz=-b[2];
  
-  fgBz=map->SolenoidField();
+  Double_t bz=-map->SolenoidField();
+  fgBz=TMath::Sign(kAlmost0Field,bz) + bz;
 
 }
 
@@ -123,3 +148,12 @@ void AliTracker::UseClusters(const AliKalmanTrack *t, Int_t from) const {
      c->Use();   
   }
 }
+
+Double_t AliTracker::GetBz(Float_t *r) {
+  //------------------------------------------------------------------
+  // Returns Bz (kG) at the point "r" .
+  //------------------------------------------------------------------
+    Float_t b[3]; fgkFieldMap->Field(r,b);
+    Double_t bz=-Double_t(b[2]);
+    return  (TMath::Sign(kAlmost0Field,bz) + bz);
+}