Bug fix in Charge() which returned half the charge for single-cathode clusters (spott...
[u/mrichter/AliRoot.git] / MUON / AliMUONPreClusterFinderV2.cxx
CommitLineData
c13ab450 1/**************************************************************************
2* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3* *
4* Author: The ALICE Off-line Project. *
5* Contributors are mentioned in the code where appropriate. *
6* *
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**************************************************************************/
15
16// $Id$
17
18#include "AliMUONPreClusterFinderV2.h"
19
20#include "AliLog.h"
21#include "AliMUONCluster.h"
22#include "AliMpVSegmentation.h"
23#include "TClonesArray.h"
24#include "TVector2.h"
25#include "AliMUONPad.h"
26#include "AliMUONVDigit.h"
27#include "AliMUONVDigitStore.h"
28
3d1463c8 29//-----------------------------------------------------------------------------
c13ab450 30/// \class AliMUONPreClusterFinderV2
31///
32/// Implementation of AliMUONVClusterFinder
33///
34/// This one ressembles the preclustering stage in the original ClusterFinderAZ
35///
36/// \author Laurent Aphecetche
3d1463c8 37//-----------------------------------------------------------------------------
c13ab450 38
39ClassImp(AliMUONPreClusterFinderV2)
40
41//_____________________________________________________________________________
42AliMUONPreClusterFinderV2::AliMUONPreClusterFinderV2()
43: AliMUONVClusterFinder(),
44 fClusters(0x0),
45 fSegmentations(0x0),
46 fDetElemId(0)
47{
48 /// ctor
49 for ( Int_t i = 0; i < 2; ++i )
50 {
51 fPads[i] = 0x0;
52 }
53}
54
55//_____________________________________________________________________________
56AliMUONPreClusterFinderV2::~AliMUONPreClusterFinderV2()
57{
58 /// dtor : note we're owner of the pads and the clusters, but not of
59 /// the remaining objects (digits, segmentations)
60 delete fClusters;
61 for ( Int_t i = 0; i < 2; ++i )
62 {
63 delete fPads[i];
64 }
65}
66
67//_____________________________________________________________________________
68Bool_t
69AliMUONPreClusterFinderV2::UsePad(const AliMUONPad& pad)
70{
71 /// Add a pad to the list of pads to be considered
72 if ( pad.DetElemId() != fDetElemId )
73 {
74 AliError(Form("Cannot add pad from DE %d to this cluster finder which is "
75 "currently dealing with DE %d",pad.DetElemId(),fDetElemId));
76 return kFALSE;
77 }
78
79 new ((*fPads[pad.Cathode()])[fPads[pad.Cathode()]->GetLast()+1]) AliMUONPad(pad);
80 // FIXME: should set the ClusterId of that new pad to be -1
81 return kTRUE;
82}
83
84//_____________________________________________________________________________
85Bool_t
86AliMUONPreClusterFinderV2::Prepare(const AliMpVSegmentation* segmentations[2],
87 const AliMUONVDigitStore& digitStore)
88// FIXME : add area on which to look for clusters here.
89{
90 /// Prepare for clustering, by giving access to segmentations and digit lists
91
92 fSegmentations = segmentations;
93
94 delete fClusters;
95 fClusters = new TClonesArray("AliMUONCluster");
96 for ( Int_t i = 0; i < 2; ++i )
97 {
98 delete fPads[i];
99 fPads[i] = new TClonesArray("AliMUONPad");
100 }
101
102 fDetElemId = -1;
103
104 TIter next(digitStore.CreateIterator());
105 AliMUONVDigit* d;
106
107 while ( ( d = static_cast<AliMUONVDigit*>(next()) ) )
108 {
109 Int_t ix = d->PadX();
110 Int_t iy = d->PadY();
111 Int_t cathode = d->Cathode();
112 AliMpPad pad = fSegmentations[cathode]->PadByIndices(AliMpIntPair(ix,iy));
113 TClonesArray& padArray = *(fPads[cathode]);
114 if ( fDetElemId == -1 )
115 {
116 fDetElemId = d->DetElemId();
117 }
118 else
119 {
120 if ( d->DetElemId() != fDetElemId )
121 {
122 AliError("Something is seriously wrong with DE. Aborting clustering");
123 return kFALSE;
124 }
125 }
126
127 AliMUONPad mpad(fDetElemId,cathode,
128 ix,iy,pad.Position().X(),pad.Position().Y(),
129 pad.Dimensions().X(),pad.Dimensions().Y(),
130 d->Charge());
131 if ( d->IsSaturated() ) mpad.SetSaturated(kTRUE);
2060b217 132 mpad.SetUniqueID(d->GetUniqueID());
c13ab450 133 new (padArray[padArray.GetLast()+1]) AliMUONPad(mpad);
134 }
135 if ( fPads[0]->GetLast() < 0 && fPads[1]->GetLast() < 0 )
136 {
137 // no pad at all, nothing to do...
138 return kFALSE;
139 }
140
141 return kTRUE;
142}
143
144//_____________________________________________________________________________
145void
146AliMUONPreClusterFinderV2::AddPad(AliMUONCluster& cluster, AliMUONPad* pad)
147{
148 /// Add a pad to a cluster
149
150 cluster.AddPad(*pad);
151 pad->SetClusterId(cluster.GetUniqueID());
152
153 Int_t cathode = pad->Cathode();
154 TClonesArray& padArray = *fPads[cathode];
155 padArray.Remove(pad);
156 TIter next(&padArray);
157
158 // Check neighbours
159 TObjArray neighbours;
160 AliMpPad p = fSegmentations[pad->Cathode()]->PadByIndices(AliMpIntPair(pad->Ix(),pad->Iy()),kTRUE);
161 Int_t nn = fSegmentations[pad->Cathode()]->GetNeighbours(p,neighbours);
162 for (Int_t in = 0; in < nn; ++in)
163 {
164 AliMpPad* p = static_cast<AliMpPad*>(neighbours.At(in));
165
166 TIter next(&padArray);
167 AliMUONPad* p2;
168
169 while ( ( p2 = static_cast<AliMUONPad*>(next()) ) )
170 {
171 if ( !p2->IsUsed() && p2->Ix()==p->GetIndices().GetFirst()
172 && p2->Iy() == p->GetIndices().GetSecond() &&
173 p2->Cathode() == pad->Cathode() )
174 {
175 AddPad(cluster,p2);
176 }
177 }
178 } // for (Int_t in = 0;
179}
180
181namespace
182{
183//_____________________________________________________________________________
184Bool_t
185AreOverlapping(const AliMUONPad& pad, const AliMUONCluster& cluster)
186{
187 /// Whether the pad overlaps with the cluster
188
189 static Double_t precision = 1E-4; // cm
190 static TVector2 precisionAdjustment(precision,precision);//-precision,-precision);
191 for ( Int_t i = 0; i < cluster.Multiplicity(); ++i )
192 {
193 AliMUONPad* testPad = cluster.Pad(i);
194 // Note: we use negative precision numbers, meaning
195 // the area of the pads will be *increased* by these small numbers
196 // prior to check the overlap by the AreOverlapping method,
197 // so pads touching only by the corners will be considered as
198 // overlapping.
199 if ( AliMUONPad::AreOverlapping(*testPad,pad,precisionAdjustment) )
200 {
201 return kTRUE;
202 }
203 }
204 return kFALSE;
205}
206}
207
208//_____________________________________________________________________________
209AliMUONCluster*
210AliMUONPreClusterFinderV2::NextCluster()
211{
212 /// Builds the next cluster, and returns it.
213
214 // Start a new cluster
215 Int_t id = fClusters->GetLast()+1;
216 AliMUONCluster* cluster = new ((*fClusters)[id]) AliMUONCluster;
217 cluster->SetUniqueID(id);
218
219 AliMUONPad* pad;
220 TIter next(fPads[0]);
221 while ( ( pad = static_cast<AliMUONPad*>(next())) && pad->IsUsed() );
222
223 if (!pad) // protection against no pad in first cathode, which might happen
224 {
225 // try other cathode
226 TIter next(fPads[1]);
227 while ( ( pad = static_cast<AliMUONPad*>(next())) && pad->IsUsed() );
228 if (!pad)
229 {
230 // we are done.
231 return 0x0;
232 }
233 // Builds (recursively) a cluster on second cathode only
234 AddPad(*cluster,pad);
235 }
236 else
237 {
238 // Builds (recursively) a cluster on first cathode only
239
240 AddPad(*cluster,pad);
241
242 // On the 2nd cathode, only add pads overlapping with the current cluster
243 TIter next1(fPads[1]);
244 AliMUONPad* testPad;
245
246 while ( ( testPad = static_cast<AliMUONPad*>(next1())))
247 {
248 if ( !testPad->IsUsed() && AreOverlapping(*testPad,*cluster) )
249 {
250 AddPad(*cluster,testPad);
251 }
252 }
253 }
254
255 if ( cluster->Multiplicity() <= 1 )
256 {
257 if ( cluster->Multiplicity() == 0 )
258 {
259 // no pad is suspicious
260 AliWarning("Got an empty cluster...");
261 }
262 // else only 1 pad (not suspicious, but kind of useless, probably noise)
263 // so we remove it from our list
264 fClusters->Remove(cluster);
265 fClusters->Compress();
266 // then proceed further
267 return NextCluster();
268 }
269
270 return cluster;
271}