1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
18 #include "AliMUONPreClusterFinderV2.h"
21 #include "AliMUONCluster.h"
22 #include "AliMpVSegmentation.h"
24 #include "TClonesArray.h"
26 #include "AliMUONPad.h"
27 #include "AliMUONVDigit.h"
28 #include "AliMUONVDigitStore.h"
30 //-----------------------------------------------------------------------------
31 /// \class AliMUONPreClusterFinderV2
33 /// Implementation of AliMUONVClusterFinder
35 /// This one ressembles the preclustering stage in the original ClusterFinderAZ
37 /// \author Laurent Aphecetche
38 //-----------------------------------------------------------------------------
40 ClassImp(AliMUONPreClusterFinderV2)
42 //_____________________________________________________________________________
43 AliMUONPreClusterFinderV2::AliMUONPreClusterFinderV2()
44 : AliMUONVClusterFinder(),
53 //_____________________________________________________________________________
54 AliMUONPreClusterFinderV2::~AliMUONPreClusterFinderV2()
56 /// dtor : note we're owner of the clusters, but not of the pads
60 //_____________________________________________________________________________
62 AliMUONPreClusterFinderV2::UsePad(const AliMUONPad& pad)
64 /// Add a pad to the list of pads to be considered
65 if ( pad.DetElemId() != fDetElemId )
67 AliError(Form("Cannot add pad from DE %d to this cluster finder which is "
68 "currently dealing with DE %d",pad.DetElemId(),fDetElemId));
72 new ((*fPads[pad.Cathode()])[fPads[pad.Cathode()]->GetLast()+1]) AliMUONPad(pad);
73 // FIXME: should set the ClusterId of that new pad to be -1
77 //_____________________________________________________________________________
79 AliMUONPreClusterFinderV2::Prepare(Int_t detElemId,
80 TClonesArray* pads[2],
81 const AliMpArea& area,
82 const AliMpVSegmentation* seg[2])
84 /// Prepare for clustering, by giving access to segmentations and digit lists
88 AliError("Handling of area not yet implemented for this class. Please check");
92 fClusters = new TClonesArray("AliMUONCluster");
95 fkSegmentations = seg;
97 fDetElemId = detElemId;
99 if ( fPads[0]->GetLast() < 0 && fPads[1]->GetLast() < 0 )
101 // no pad at all, nothing to do...
108 //_____________________________________________________________________________
110 AliMUONPreClusterFinderV2::AddPad(AliMUONCluster& cluster, AliMUONPad* pad)
112 /// Add a pad to a cluster
114 cluster.AddPad(*pad);
115 pad->SetClusterId(cluster.GetUniqueID());
117 Int_t cathode = pad->Cathode();
118 TClonesArray& padArray = *fPads[cathode];
119 padArray.Remove(pad);
120 TIter next(&padArray);
123 TObjArray neighbours;
124 AliMpPad p = fkSegmentations[pad->Cathode()]->PadByIndices(pad->Ix(),pad->Iy(),kTRUE);
125 Int_t nn = fkSegmentations[pad->Cathode()]->GetNeighbours(p,neighbours);
126 for (Int_t in = 0; in < nn; ++in)
128 AliMpPad* p1 = static_cast<AliMpPad*>(neighbours.At(in));
130 TIter next2(&padArray);
133 while ( ( p2 = static_cast<AliMUONPad*>(next2()) ) )
135 if ( !p2->IsUsed() && p2->Ix()==p1->GetIx()
136 && p2->Iy() == p1->GetIy() &&
137 p2->Cathode() == pad->Cathode() )
142 } // for (Int_t in = 0;
147 //_____________________________________________________________________________
149 AreOverlapping(const AliMUONPad& pad, const AliMUONCluster& cluster)
151 /// Whether the pad overlaps with the cluster
153 static Double_t precision = 1E-4; // cm
154 static TVector2 precisionAdjustment(precision,precision);//-precision,-precision);
155 for ( Int_t i = 0; i < cluster.Multiplicity(); ++i )
157 AliMUONPad* testPad = cluster.Pad(i);
158 // Note: we use negative precision numbers, meaning
159 // the area of the pads will be *increased* by these small numbers
160 // prior to check the overlap by the AreOverlapping method,
161 // so pads touching only by the corners will be considered as
163 if ( AliMUONPad::AreOverlapping(*testPad,pad,precisionAdjustment) )
172 //_____________________________________________________________________________
174 AliMUONPreClusterFinderV2::NextCluster()
176 /// Builds the next cluster, and returns it.
178 // Start a new cluster
179 Int_t id = fClusters->GetLast()+1;
180 AliMUONCluster* cluster = new ((*fClusters)[id]) AliMUONCluster;
181 cluster->SetUniqueID(id);
184 TIter next(fPads[0]);
185 while ( ( pad = static_cast<AliMUONPad*>(next())) && pad->IsUsed() ) {}
187 if (!pad) // protection against no pad in first cathode, which might happen
190 TIter next2(fPads[1]);
191 while ( ( pad = static_cast<AliMUONPad*>(next2())) && pad->IsUsed() ) {}
197 // Builds (recursively) a cluster on second cathode only
198 AddPad(*cluster,pad);
202 // Builds (recursively) a cluster on first cathode only
204 AddPad(*cluster,pad);
206 // On the 2nd cathode, only add pads overlapping with the current cluster
207 TIter next1(fPads[1]);
210 while ( ( testPad = static_cast<AliMUONPad*>(next1())))
212 if ( !testPad->IsUsed() && AreOverlapping(*testPad,*cluster) )
214 AddPad(*cluster,testPad);
219 if ( cluster->Multiplicity() <= 1 )
221 if ( cluster->Multiplicity() == 0 )
223 // no pad is suspicious
224 AliWarning("Got an empty cluster...");
226 // else only 1 pad (not suspicious, but kind of useless, probably noise)
227 // so we remove it from our list
228 fClusters->Remove(cluster);
229 fClusters->Compress();
230 // then proceed further
231 return NextCluster();