Additional protection when the energy loss cannot be treated using Bethe-Bloch formula

[u/mrichter/AliRoot.git] / PHOS / AliPHOSSurvey.cxx

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 * Author: The ALICE Off-line Project.                                    *
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 * documentation strictly for non-commercial purposes is hereby granted   *
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 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
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/* $Id$ */

/* History of cvs commits:
 *
 * $Log$
 */

// Objects of this class read txt file with survey (photogrammetry) data
// and convert the data into AliAlignObjAngles of alignable PHOS volumes.
// It can be used as a base class, you need to override GetStripTransformation.
// AliPHOSSurvey inherits TObject only to use AliLog "functions".
// Author: Timur Pocheptsov (JINR)

#include <fstream>

#include <TClonesArray.h>
#include <TGeoManager.h>
#include <TString.h>
#include <TMath.h>

#include "AliPHOSEMCAGeometry.h"
#include "AliAlignObjAngles.h"
#include "AliPHOSGeometry.h"
#include "AliPHOSSurvey.h"
#include "AliLog.h"

ClassImp(AliPHOSSurvey)

//____________________________________________________________________________
AliPHOSSurvey::AliPHOSSurvey()
                : fStripData()
{
  //Default constructor.
}

namespace {

  struct Strip_t {
    Double_t fX1;
    Double_t fZ1;
    Double_t fX2;
    Double_t fZ2;
  };

}

//____________________________________________________________________________
AliPHOSSurvey::AliPHOSSurvey(const TString &txtFileName)
                : fStripData()
{
  //Read survey data from txt file.
  const AliPHOSGeometry *phosGeom = AliPHOSGeometry::GetInstance("IHEP", "IHEP");
  if (!phosGeom) {
    AliError("Cannot obtain AliPHOSGeometry instance.");
    return;
  }

  std::ifstream inputFile(txtFileName.Data());
  if (!inputFile) {
    AliError(("Cannot open the survey file " + txtFileName).Data());
    return;
  }

  AliPHOSEMCAGeometry  * emcaGeom = phosGeom->GetEMCAGeometry();
  const Int_t strNum   = emcaGeom->GetNStripX() * emcaGeom->GetNStripZ();
  const Float_t *strip = emcaGeom->GetStripHalfSize();
  const Float_t *cell  = emcaGeom->GetSteelCellHalfSize(); 

  std::vector<Strip_t> idealStrips(strNum);
  for (Int_t ix = 0, stripNumber = 0; ix < emcaGeom->GetNStripX(); ++ix) {
    for (Int_t iz = 0; iz < emcaGeom->GetNStripZ(); ++iz) {
      Strip_t &str = idealStrips[stripNumber++];
      str.fX1 = ix * 2 * strip[0];
      str.fX2 = str.fX1 + 14 * cell[0];
      str.fZ1 = iz * 2 * strip[2];
      str.fZ2 = str.fZ1 + 2 * cell[2];
    }
  }

  Int_t dummyInt = 0;
  Double_t dummyY = 0.;
  std::vector<Double_t> xReal(strNum * 2), zReal(strNum * 2);
  for (Int_t i = 0; i < strNum * 2; ++i) {
    if (!inputFile) {
      AliError("Error while reading input file.");
      return;
    }
    inputFile>>dummyInt>>xReal[i]>>dummyY>>zReal[i];
    xReal[i] *= 0.1;
    zReal[i] *= 0.1;
  }

  std::vector<Strip_t> realStrips(strNum);
  for (Int_t j = 0, stripNumber = 0; j < emcaGeom->GetNStripX() * 2; j += 2) {
    for (Int_t i = 0; i < emcaGeom->GetNStripZ(); ++i) {
      Strip_t &str = realStrips[stripNumber++];
      str.fX1 = xReal[i + j * emcaGeom->GetNStripZ()];
      str.fZ1 = zReal[i + j * emcaGeom->GetNStripZ()];
      str.fX2 = xReal[i + (j + 1) * emcaGeom->GetNStripZ()];
      str.fZ2 = zReal[i + (j + 1) * emcaGeom->GetNStripZ()];
    }
  }

  fStripData.resize(strNum);
  for (Int_t i = 0; i < strNum; ++i) {
    const Strip_t &real = realStrips[i];
    const Strip_t &ideal = idealStrips[i];
    Transformation_t &t = fStripData[i];
    t.fTheta = TMath::ATan((real.fZ2 - real.fZ1)  / (real.fX2 - real.fX1)) - 
               TMath::ATan((ideal.fZ2 - ideal.fZ1) / (ideal.fX2 - ideal.fX1));
    t.fTheta *= TMath::RadToDeg();
    t.fXShift = (real.fX1 + real.fX2) / 2 - (ideal.fX1 + ideal.fX2) / 2;
    t.fZShift = (real.fZ1 + real.fZ2) / 2 - (ideal.fZ1 + ideal.fZ2) / 2;
    t.fYShift = 0., t.fPsi = 0., t.fPhi = 0.;
  }
}

//____________________________________________________________________________
void AliPHOSSurvey::CreateAliAlignObjAngles(TClonesArray &array)
{
  //Create AliAlignObjAngles.
  const AliPHOSGeometry * phosGeom = AliPHOSGeometry::GetInstance("IHEP", "IHEP");
  if (!phosGeom) {
    AliError("Cannot obtain AliPHOSGeometry instance.");
    return;
  }

  if (!gGeoManager) {
    AliWarning("Cannot create local transformations for strip units - gGeoManager does not exist.");
    AliInfo("Null shifts and rotations will be created instead.");
    return CreateNullObjects(array, phosGeom);
  }

  AliPHOSEMCAGeometry * emcaGeom = phosGeom->GetEMCAGeometry();
  Int_t arrayInd = array.GetEntries(), iIndex = 0;
  AliAlignObj::ELayerID iLayer = AliAlignObj::kInvalidLayer;
  UShort_t volid = AliAlignObj::LayerToVolUID(iLayer,iIndex);

  for (Int_t module = 1; module <= phosGeom->GetNModules(); ++module) {
    for (Int_t i = 0, stripNum = 0; i < emcaGeom->GetNStripX(); ++i) {
      for (Int_t j = 0; j < emcaGeom->GetNStripZ(); ++j) {
        TString stripName(TString::Format("PHOS/Module%d/Strip_%d_%d", module, i, j));
        Transformation_t t(GetStripTransformation(stripNum++, module));
        new(array[arrayInd])
          AliAlignObjAngles(
                            stripName.Data(), volid, 
                            t.fXShift, t.fYShift, t.fZShift, 
                            -t.fPsi, -t.fTheta, -t.fPhi, 
                            kFALSE
                           );
        ++arrayInd;
      }
    }
  }
}

//____________________________________________________________________________
void AliPHOSSurvey::CreateNullObjects(TClonesArray &array, const AliPHOSGeometry *phosGeom)const
{
  //Create null shifts and rotations.
  const AliPHOSEMCAGeometry * emcaGeom = phosGeom->GetEMCAGeometry();
  Int_t arrayInd = array.GetEntries(), iIndex = 0;
  AliAlignObj::ELayerID iLayer = AliAlignObj::kInvalidLayer;
  UShort_t volid = AliAlignObj::LayerToVolUID(iLayer,iIndex);

  for (Int_t module = 1; module <= phosGeom->GetNModules(); ++module)
    for (Int_t i = 0; i < emcaGeom->GetNStripX(); ++i)
      for (Int_t j = 0; j < emcaGeom->GetNStripZ(); ++j) {
        TString stripName(TString::Format("PHOS/Module%d/Strip_%d_%d", module, i, j));
        new(array[arrayInd]) AliAlignObjAngles(stripName.Data(), volid, 0., 0., 0., 0., 0., 0., kTRUE);
        ++arrayInd;
      }
}

//____________________________________________________________________________
AliPHOSSurvey::Transformation_t AliPHOSSurvey::GetStripTransformation(Int_t stripIndex, Int_t module)const
{
  //Strip 'stripIndex' transformation.
  const Transformation_t t = {0., 0., 0., 0., 0., 0.};
  if (module != 3 || !fStripData.size())
    return t;
  return fStripData[stripIndex];
}