Support (staggered) per-layer cluster input in ITS/TPC matching

DataFormats/Detectors/GlobalTracking/include/DataFormatsGlobalTracking/RecoContainer.h

@@ -27,6 +27,7 @@
 #include "SimulationDataFormat/MCTruthContainer.h"
 #include "SimulationDataFormat/ConstMCTruthContainer.h"
 #include "DataFormatsCTP/LumiInfo.h"
+#include "DataFormatsITSMFT/ClusterID.h"
 #include <gsl/span>
 #include <memory>
 
@@ -188,8 +189,8 @@ namespace globaltracking
 {
 
 // max number of layers for which the ITS/MFT clusters, ROF records and patterns can be provided separately
-constexpr int MaxITSLayers = 7;
-constexpr int MaxMFTLayers = 10;
+constexpr int MaxITSLayers = o2::itsmft::MaxITSClusLayers;
+constexpr int MaxMFTLayers = o2::itsmft::MaxMFTClusLayers;
 
 // helper class to request DPL input data from the processor specs definition
 struct DataRequest {

DataFormats/Detectors/ITSMFT/ITS/include/DataFormatsITS/TrackITS.h

@@ -221,13 +221,6 @@ class TrackITSExt : public TrackITS
 
   GPUhdDefault() TrackITSExt(const TrackITSExt& t) = default;
 
-  void setClusterIndex(int l, int i)
-  {
-    int ncl = getNumberOfClusters();
-    mIndex[ncl++] = (l << 28) + i;
-    getClusterRefs().setEntries(ncl);
-  }
-
   GPUhdi() int getClusterIndex(int lr) const { return mIndex[lr]; }
 
   GPUh() int getFirstLayerClusterIndex() const

DataFormats/Detectors/ITSMFT/common/include/DataFormatsITSMFT/ClusterID.h

@@ -0,0 +1,43 @@
+// Copyright 2019-2020 CERN and copyright holders of ALICE O2.
+// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
+// All rights not expressly granted are reserved.
+//
+// This software is distributed under the terms of the GNU General Public
+// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+/// \file ClusterID.h
+/// \brief Composition/decomposition of the ITS/MFT cluster IDs referring to per-layer cluster arrays
+/// \author ruben.shahoyan@cern.ch
+
+#ifndef ALICEO2_ITSMFT_CLUSTERID_H
+#define ALICEO2_ITSMFT_CLUSTERID_H
+
+namespace o2::itsmft
+{
+
+// max number of layers for which the ITS/MFT clusters, ROF records and patterns can be provided separately
+constexpr int MaxITSClusLayers = 7;
+constexpr int MaxMFTClusLayers = 10;
+constexpr int MaxClusLayers = MaxITSClusLayers > MaxMFTClusLayers ? MaxITSClusLayers : MaxMFTClusLayers;
+
+///< With the per-layer (staggered readout) ITS/MFT clusters input the clusters are referred to by the
+///< composed ID (layer << ClusLayerShift) + index_in_layer. With a single (monolithic) clusters input
+///< all clusters sit in the layer slot 0, hence the composed ID coincides with the flat cluster index
+///< and the same decoding works for both cases.
+///< Note: the bit 31 is excluded from the layer field, since the negative values of the composed ID
+///< are reserved for the "no cluster" flags.
+constexpr int ClusLayerShift = 27;
+constexpr int ClusIndexMask = (0x1 << ClusLayerShift) - 1;
+static_assert((1 << (31 - ClusLayerShift)) >= MaxClusLayers, "ClusLayerShift leaves no room for the layer ID");
+
+constexpr int composeClusID(int lr, int idx) { return (lr << ClusLayerShift) + idx; }
+constexpr int clusID2Layer(int id) { return id >> ClusLayerShift; }
+constexpr int clusID2Index(int id) { return id & ClusIndexMask; }
+
+} // namespace o2::itsmft
+
+#endif

Detectors/GlobalTracking/include/GlobalTracking/MatchTPCITSParams.h

@@ -85,6 +85,8 @@ struct MatchTPCITSParams : public o2::conf::ConfigurableParamHelper<MatchTPCITSP
   float nABSigmaZ = 4.;            ///< nSigma cut on afterburner track-cluster Z distance
   float err2ABExtraY = 0.1 * 0.1;  ///< extra "systematic" error on Y
   float err2ABExtraZ = 0.1 * 0.1;  ///< extra "systematic" error on Z
+  float abROFMarginMUS = 0.f;      ///< margin in \mus for matching interaction candidate time to ITS ROFs in the AfterBurner (clamped to below half of the shortest ROF length)
+  float itsTimeStampMarginBC = 1.f; ///< safety margin in BC applied to both edges of the ITS track time-stamp uncertainty interval
 
   int verbosity = 0; ///< verbosit level