class AliHMPIDRecon: public TNamed

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init of data members
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Init some variables
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Delete variables
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 Pattern recognition method based on Hough transform
 Arguments:   pTrk     - track for which Ckov angle is to be found
              pCluLst  - list of clusters for this chamber
   Returns:            - track ckov angle, [rad],

 Finds Cerenkov angle  for this photon candidate
 Arguments: cluX,cluY - position of cadidate's cluster
 Returns: Cerenkov angle

Trace forward a photon from (x,y) up to PC
 Arguments: dirCkov photon vector in LORS
   Returns: pos of traced photon at PC

Theta Cerenkov reconstruction
 Arguments: dirCkov photon vector in LORS
   Returns: thetaCer of photon in TRS
              phiCer of photon in TRS
  TVector3 dirTrk;
  dirTrk.SetMagThetaPhi(1,fTrkDir.Theta(),fTrkDir.Phi());
  Double_t thetaCer = TMath::ACos(dirCkov*dirTrk);

Theta Cerenkov reconstruction
 Arguments: dirCkov photon vector in TRS
   Returns: thetaCer of photon in LORS
              phiCer of photon in LORS

 Find area covered in the PC acceptance
 Arguments: ckovAng - cerenkov angle
            level   - precision in finding area and portion of ring accepted (multiple of 50)
   Returns: area of the ring in cm^2 for given theta ckov

 It finds the intersection of the line for 2 points traced as photons
 and the edge of a given PC
 Arguments: 2 points obtained tracing the photons
   Returns: intersection point with detector (PC) edges

 Loops on all Ckov candidates and estimates the best Theta Ckov for a ring formed by those candidates. Also estimates an error for that Theat Ckov
 collecting errors for all single Ckov candidates thetas. (Assuming they are independent)
 Arguments: iNclus- total number of clusters in chamber for background estimation
    Return: best estimation of track Theta ckov

 Flag photon candidates if their individual ckov angle is inside the window around ckov angle returned by  HoughResponse()
 Arguments: ckov- value of most probable ckov angle for track as returned by HoughResponse()
   Returns: number of photon candidates happened to be inside the window

 Add AliHMPIDcluster object to ESD friends

 Trace a single Ckov photon from emission point somewhere in radiator up to photocathode taking into account ref indexes of materials it travereses
 Arguments: ckovThe,ckovPhi- photon ckov angles in TRS, [rad]
   Returns: distance between photon point on PC and track projection

 Finds an intersection point between a line and XY plane shifted along Z.
 Arguments:  dir,pos   - vector along the line and any point of the line
             z         - z coordinate of plain
   Returns:  none
   On exit:  pos is the position if this intesection if any

 Refract direction vector according to Snell law
 Arguments:
            n1 - ref idx of first substance
            n2 - ref idx of second substance
   Returns: none
   On exit: dir is new direction

    fIdxMip = mipId;

 To find the acceptance of the ring even from external inputs.