class HMdcVertexWriter: public HReconstructor

_HADES_CLASS_DESCRIPTION


 HMdcVertexWriter

 This class writes the reconstructed Event vertex to an root output file
 which will be later used for the preparation of the simulations files for
 the event embeddding. The class has to connect last to the task list to not
 write out skipped events.

 Output file name :
 1. If the outputfile is set in HADES it will be equal outputfile_vertex.root.
    The file will be splitted in the same way as the the root output file.
 2. If the outputdir is set filenames are derived in the same way but the dir
    corresponds to the set one.
 3. If no outputdir is set and no output file is set in HADES the outputfile
    will be equal to the current inputfile_vertex.root
 4. if setOutputFile( filename_includingpath) is used all automatic derivation
    from HADES input or outputfile name is disabled (manual mode, use this when
    running from HRootSource)

  static void HMdcVertexWriter::setSkipNoVertex (Bool_t skip = kTRUE){doSkipNoVertex = skip; }
  With doSkipNoVertex == kTRUE (default : kTRUE) events without calculated vertex will be skipped.

  with setVertexType(Int_t type)
  kVertexCluster  = 1,(cluster finder vertex (mean middle of target segment position in z, x,y on 0,0))
  kVertexSegment  = 2 (Mdc inner segments used to estimated the vertex,default),
  kVertexParticle = 3 (fully reconstructed and sorted HParticleCand used to estimate the vertex),
  kVertexClusterMeanXY = 4 (user provided mean x,y, z from vertexCluster)
  kVertexGeant         = 5 (use primary vertex from HGeant)
  the reconstructed vertex type can be selected.
  with void setUserSelectionEvent(Bool_t (*function)(TObjArray* ),TObjArray* params=0) the user
  can set a event selection function of the form

  Bool_t myEventSelection(TObjArray* params){

   if(goodEvent) return kTRUE;
   else          return kFALSE;
 }

  where params cand be used to pass parameters for the used
  event selection. The event selection should be used in combination
  with setSkipNoVertex(kTRUE)