RICH/AliRICHHelix.cxx

   1 #include "AliRICHHelix.h" //class header
   2 #include <TPolyLine3D.h>  //Draw()
   3
   4 ClassImp(AliRICHHelix)
   5 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
   6 AliRICHHelix::AliRICHHelix(Double_t p,Double_t theta,Double_t phi,Double_t bz):TObject(),
   7   fX0(TVector3(0,0,0)),
   8   fP0(TVector3(0,0,0)),
   9   fX(TVector3(0,0,0)),
  10   fP(TVector3(0,0,0)),
  11   fLen(0),
  12   fQ(0),
  13   fBz(bz),
  14   fPosRad(TVector2(0,0)),
  15   fPosPc(TVector2(0,0)),
  16   fPloc(TVector3(0,0,0))
  17 {
  18   fP0.SetMagThetaPhi(p,theta*TMath::DegToRad(),phi*TMath::DegToRad());     fP=fP0;
  19 }
  20 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  21 void  AliRICHHelix::Print(Option_t *opt) const
  22 {
  23 // Debug printout
  24   Printf("%s helix for Q=%i in B=(0,0,%.2f) tesla",opt,fQ,fBz);
  25   Printf("Helix parametrised  @ x0=(%6.2f,%6.2f,%6.2f) cm p0=(%6.2f,%6.2f,%6.2f) GeV  P=%.2f GeV Theta=%.2f Phi=%.2f degrees",
  26                                 fX0.X(),fX0.Y(),fX0.Z(),    fP0.Px(),fP0.Py(),fP0.Pz(), fP0.Mag(),fP0.Theta()*TMath::RadToDeg(),fP0.Phi()*TMath::RadToDeg());
  27   Printf("@ %7.2f cm           x=(%6.2f,%6.2f,%6.2f) cm  p=(%6.2f,%6.2f,%6.2f) GeV  P=%.2f GeV Theta=%.2f Phi=%.2f degrees",
  28            fLen,              fX.X(), fX.Y(), fX.Z(),       fP.Px(),fP.Py(),fP.Pz(), fP.Mag(), fP.Theta()*TMath::RadToDeg(),fP.Phi()*TMath::RadToDeg());
  29   Printf("             in LORS   rad=(%5.2f,%5.2f)  pc=(%5.2f,%5.2f)",fPosRad.X(), fPosRad.Y(),fPosPc.X(),fPosPc.Y());
  30 }
  31 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  32 void AliRICHHelix::Draw(const Option_t *)
  33 {
  34 // Draw helix by a set of points seperated by 1 cm distance
  35
  36   const Int_t kNpoints=500;
  37   TPolyLine3D *pHelDraw = new TPolyLine3D(kNpoints); pHelDraw->SetLineColor(kGreen);
  38   for(Int_t i=0;i<kNpoints;i++) {
  39     Propagate(i);
  40     pHelDraw->SetPoint(i,fX.X(),fX.Y(),fX.Z());
  41   }
  42   pHelDraw->Draw();
  43 }