class AliITS: public AliDetector

 Default initializer for ITS
      The default constructor of the AliITS class. In addition to
 creating the AliITS class it zeros the variables fIshunt (a member
 of AliDetector class), fEuclidOut, and fIdN, and zeros the pointers
 fIdSens, and fIdName. The AliDetector default constructor
 is also called.

     The standard Constructor for the ITS class.
 It also zeros the variables
 fIshunt (a member of AliDetector class), fEuclidOut, and zeros
 the pointers fIdSens and fIdName. To help in displaying hits via the
 ROOT macro display.C AliITS also sets the marker color to red. The
 variables passes with this constructor, const char *name and *title,
 are used by the constructor of AliDetector class. See AliDetector
 class for a description of these parameters and its constructor
 functions.
 Inputs:
   Char_t *title  Simulation title for the ITS
 Outputs:
   none.
 Return:
   none.

     The standard Constructor for the ITS class.
 It also zeros the variables
 fIshunt (a member of AliDetector class), fEuclidOut, and zeros
 the pointers fIdSens and fIdName. To help in displaying hits via the
 ROOT macro display.C AliITS also sets the marker color to red. The
 variables passes with this constructor, const char *name and *title,
 are used by the constructor of AliDetector class. See AliDetector
 class for a description of these parameters and its constructor
 functions.

 Default destructor for ITS.
     The default destructor of the AliITS class. In addition to deleting
 the AliITS class it deletes the memory pointed to by
 fIdSens, fIdName, fDetTypeSim and it's contents.
 Inputs:
      none.
 Outputs:
      none.
 Return:
      none.

 Creates the AliITSDigitizer in a standard way for use via AliModule.
 This function can not be included in the .h file because of problems
 with the order of inclusion (recursive).
 Inputs:
    AliDigitizationInput* digInput  The Manger class for Digitization
 Output:
    none.
 Return:
    A new AliITSRunDigitizer (cast as a AliDigitizer).

 Initializer ITS after it has been built
     This routine initializes the AliITS class. It is intended to be
 called from the Init function in AliITSv?. Besides displaying a banner
 indicating that it has been called it initializes the array fIdSens
 and sets the default segmentation, response, digit and raw cluster
 classes therefore it should be called after a call to CreateGeometry.
 Inputs:
      none.
 Outputs:
      none.
 Return:
      none.

 sets the default segmentation, response, digit and raw cluster classes.
 Inputs:
      none.
 Outputs:
      none.
 Return:
      none.

 sets the default simulation.
 Inputs:
      none.
 Outputs:
      none.
 Return:
      none.

 Creates Tree branches for the ITS.
 Inputs:
      Option_t *option    String of Tree types S,D, and/or R.
      const char *file    String of the file name where these branches
                          are to be stored. If blank then these branches
                          are written to the same tree as the Hits were
                          read from.
 Outputs:
      none.
 Return:
      none.

 Set branch address for the Trees.
 Inputs:
      none.
 Outputs:
      none.
 Return:
      none.

 Add an ITS hit
     The function to add information to the AliITShit class. See the
 AliITShit class for a full description. This function allocates the
 necessary new space for the hit information and passes the variable
 track, and the pointers *vol and *hits to the AliITShit constructor
 function.
 Inputs:
      Int_t   track   Track number which produced this hit.
      Int_t   *vol    Array of Integer Hit information. See AliITShit.h
      Float_t *hits   Array of Floating Hit information.  see AliITShit.h
 Outputs:
      none.
 Return:
      none.

 fill the modules with the sorted by module hits; add hits from
 background if option=Add.

 fill the modules with the sorted by module hits;
 can be called many times to do a merging
 Inputs:
      TTree *treeH  The tree containing the hits to be copied into
                    the modules.
      Int_t mask    The track number mask to indecate which file
                    this hits came from.
 Outputs:
      none.
 Return:
      none.

 Initialize the modules array.
 Inputs:
      Int_t size  Size of array of the number of modules to be
                  created. If size <=0 then the number of modules
                  is gotten from AliITSgeom class kept in fITSgeom.
 Outputs:
      Int_t &nmodules The number of modules existing.
 Return:
      none.

 Standard Hits to summable Digits function.
 Inputs:
      none.
 Outputs:
      none.

   Keep galice.root for signal and name differently the file for
 background when add! otherwise the track info for signal will be lost !
 the condition below will disappear when the geom class will be
 initialized for all versions - for the moment it is only for v5 !
 7 is the SDD beam test version.
 Inputs:
      Int_t evnt       Event to be processed.
      Int_t bgrev      Background Hit tree number.
      Int_t nmodules   Not used.
      Option_t *option String indicating if merging hits or not. To
                       merge hits set equal to "Add". Otherwise no
                       background hits are considered.
      Test_t *filename File name containing the background hits..
 Outputs:
      none.
 Return:
      none.

 Turn hits into SDigits

   Keep galice.root for signal and name differently the file for
 background when add! otherwise the track info for signal will be lost !
 the condition below will disappear when the geom class will be
 initialized for all versions - for the moment it is only for v5 !
 7 is the SDD beam test version.
 Inputs:
      Int_t evnt       Event to be processed.
      Int_t bgrev      Background Hit tree number.
      Int_t nmodules   Not used.
      Option_t *option String indicating if merging hits or not. To
                       merge hits set equal to "Add". Otherwise no
                       background hits are considered.
      Test_t *filename File name containing the background hits..
 Outputs:
      none.
 Return:
      none.

 keep galice.root for signal and name differently the file for
 background when add! otherwise the track info for signal will be lost !
 the condition below will disappear when the geom class will be
 initialized for all versions - for the moment it is only for v5 !
 Inputs:
      Int_t evnt       Event to be processed.
      Int_t bgrev      Background Hit tree number.
      Int_t size       Size used by InitModules. See InitModules.
      Option_t *opt0   Option passed to FillModules. See FillModules.
      Option_t *opt1   String indicating if merging hits or not. To
                       merge hits set equal to "Add". Otherwise no
                       background hits are considered.
      Test_t *flnm     File name containing the background hits..
 Outputs:
      none.
 Return:
      none.

 This function creates ITS clusters

 Tries to find mother's labels

 Standard Summable digits to Digits function.
 Inputs:
      none.
 Outputs:
      none.

 Reset number of digits and the digits array for the ITS detector.
 Inputs:
      none.
 Outputs:
      none.

 Reset number of digits and the digits array for this branch.
 Inputs:
      none.
 Outputs:
      none.

 Adds the a module full of summable digits to the summable digits tree.
 Inputs:
      AliITSpListItem &sdig   SDigit to be added to SDigits tree.
 Outputs:
      none.
 Return:
      none.

    Add a simulated digit.
 Inputs:
      Int_t id        Detector type number.
      AliITSdigit *d  Digit to be added to the Digits Tree. See
                      AliITSdigit.h
 Outputs:
      none.
 Return:
      none.

   Add a simulated digit to the list.
 Inputs:
      Int_t id        Detector type number.
      Float_t phys    Physics indicator. See AliITSdigits.h
      Int_t *digits   Integer array containing the digits info. See
                      AliITSdigit.h
      Int_t *tracks   Integer array [AliITSdigitS?D::GetNTracks()]
                      containing the track numbers that contributed to
                      this digit.
      Int_t *hits     Integer array [AliITSdigitS?D::GetNTracks()]
                      containing the hit numbers, from AliITSmodule, that
                      contributed to this digit.
      Float_t *charge Floating point array of the signals contributed
                      to this digit by each track.
 Outputs:
      none.
 Return:
      none.

 convert digits of the current event to raw data

builds ITSgetter (AliLoader type)
if detector wants to use castomized getter, it must overload this method

 Converts RAW data to SDigits

 Get TreeS

reads new geometry from TGeo
   AliDebug(1,"Delete ITSgeom and create a new one reading TGeo");

 create an AliITSTrigger object (and set trigger conditions as input)

 This method write FO signals in Digits tree both in Hits2Digits
 or SDigits2Digits

Standard Classes

Simulation Geometry
 get geometry version - detailed (major) or coarse (minor)

Geometry Transformations

 ITS geometry functions From Simulation

 return pointer to the array of modules

Necessary general Classes

Configuration Methods (per detector type)
 Determines which ITS subdetectors will be processed. Effects
 digitization, and Reconstruction only.

 Returns the list of ITS subdetectors that will be processed.

 Set calibration

 Set segmentation for Simulation

 Set simulation

 Set simulation

Hits