From e700e09af60d90633c45586e578d2a63a6d75eb3 Mon Sep 17 00:00:00 2001
From: Fabrizio Grosa <fabrizio.grosa@cern.ch>
Date: Tue, 25 Apr 2023 21:39:22 +0200
Subject: [PATCH] Adapt tracker to work with 8 layers for ITS3

---
 Detectors/ITSMFT/ITS/tracking/CMakeLists.txt       |  7 +++++++
 .../tracking/include/ITStracking/IndexTableUtils.h |  4 ++--
 .../ITSMFT/ITS/tracking/include/ITStracking/Road.h |  4 ++++
 .../ITS/tracking/include/ITStracking/TimeFrame.h   |  2 ++
 .../tracking/include/ITStracking/TrackerTraits.h   |  2 +-
 Detectors/ITSMFT/ITS/tracking/src/TimeFrame.cxx    | 14 ++++++++++++++
 6 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/Detectors/ITSMFT/ITS/tracking/CMakeLists.txt b/Detectors/ITSMFT/ITS/tracking/CMakeLists.txt
index 16a1595a2d6c5..25e19f6a4ee00 100644
--- a/Detectors/ITSMFT/ITS/tracking/CMakeLists.txt
+++ b/Detectors/ITSMFT/ITS/tracking/CMakeLists.txt
@@ -9,6 +9,13 @@
 # granted to it by virtue of its status as an Intergovernmental Organization
 # or submit itself to any jurisdiction.
 
+# see if its3 4-layer tracking option is enabled
+option(ENABLE_ITS3_4L "Enable its3 4-layer tracking option" OFF)
+if (ENABLE_ITS3_4L)
+  MESSAGE(STATUS "Enable its3 4-layer tracking option")
+  add_definitions(-DENABLE_ITS3_4L)
+endif()
+
 o2_add_library(ITStracking
                TARGETVARNAME targetName
                SOURCES src/ClusterLines.cxx
diff --git a/Detectors/ITSMFT/ITS/tracking/include/ITStracking/IndexTableUtils.h b/Detectors/ITSMFT/ITS/tracking/include/ITStracking/IndexTableUtils.h
index 9bdc3a813092d..ed4027f77f360 100644
--- a/Detectors/ITSMFT/ITS/tracking/include/ITStracking/IndexTableUtils.h
+++ b/Detectors/ITSMFT/ITS/tracking/include/ITStracking/IndexTableUtils.h
@@ -48,8 +48,8 @@ class IndexTableUtils
   int mNzBins = 0;
   int mNphiBins = 0;
   float mInversePhiBinSize = 0.f;
-  float mLayerZ[7] = {0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f};
-  float mInverseZBinSize[7] = {0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f};
+  float mLayerZ[8] = {0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f};
+  float mInverseZBinSize[8] = {0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f};
 };
 
 template <class T>
diff --git a/Detectors/ITSMFT/ITS/tracking/include/ITStracking/Road.h b/Detectors/ITSMFT/ITS/tracking/include/ITStracking/Road.h
index 06a6933d39834..6ffc82c637334 100644
--- a/Detectors/ITSMFT/ITS/tracking/include/ITStracking/Road.h
+++ b/Detectors/ITSMFT/ITS/tracking/include/ITStracking/Road.h
@@ -60,7 +60,11 @@ class Road final
   }
 
  private:
+#ifndef ENABLE_ITS3_4L
   int mCellIds[maxRoadSize];
+#else
+  int mCellIds[maxRoadSize + 1];
+#endif
   // int mLabel;
   unsigned char mRoadSize;
   bool mIsFakeRoad;
diff --git a/Detectors/ITSMFT/ITS/tracking/include/ITStracking/TimeFrame.h b/Detectors/ITSMFT/ITS/tracking/include/ITStracking/TimeFrame.h
index f09a3778a9471..f21bb813af1ba 100644
--- a/Detectors/ITSMFT/ITS/tracking/include/ITStracking/TimeFrame.h
+++ b/Detectors/ITSMFT/ITS/tracking/include/ITStracking/TimeFrame.h
@@ -202,6 +202,8 @@ class TimeFrame
   void addTrackingFrameInfoToLayer(int layer, T&&... args);
   void addClusterExternalIndexToLayer(int layer, const int idx);
 
+  void resizeVectors(int nLayers);
+
   /// Debug and printing
   void checkTrackletLUTs();
   void printROFoffsets();
diff --git a/Detectors/ITSMFT/ITS/tracking/include/ITStracking/TrackerTraits.h b/Detectors/ITSMFT/ITS/tracking/include/ITStracking/TrackerTraits.h
index e468a3628f82c..171b45afbd22d 100644
--- a/Detectors/ITSMFT/ITS/tracking/include/ITStracking/TrackerTraits.h
+++ b/Detectors/ITSMFT/ITS/tracking/include/ITStracking/TrackerTraits.h
@@ -136,7 +136,7 @@ inline const int4 TrackerTraits::getBinsRect(const Cluster& currentCluster, int
 
 inline void TrackerTraits::initialiseTimeFrame(const int iteration)
 {
-  mTimeFrame->initialise(iteration, mTrkParams[iteration], 7);
+  mTimeFrame->initialise(iteration, mTrkParams[iteration], mTrkParams[iteration].NLayers);
   setIsGPU(false);
 }
 
diff --git a/Detectors/ITSMFT/ITS/tracking/src/TimeFrame.cxx b/Detectors/ITSMFT/ITS/tracking/src/TimeFrame.cxx
index 2a0eeb1902fb6..05233cac73602 100644
--- a/Detectors/ITSMFT/ITS/tracking/src/TimeFrame.cxx
+++ b/Detectors/ITSMFT/ITS/tracking/src/TimeFrame.cxx
@@ -455,6 +455,20 @@ void TimeFrame::checkTrackletLUTs()
   }
 }
 
+void TimeFrame::resizeVectors(int nLayers)
+{
+  mMinR.resize(nLayers, 10000.);
+  mMaxR.resize(nLayers, -1.);
+  mClusters.resize(nLayers);
+  mUnsortedClusters.resize(nLayers);
+  mTrackingFrameInfo.resize(nLayers);
+  mClusterExternalIndices.resize(nLayers);
+  mUsedClusters.resize(nLayers);
+  mROframesClusters.resize(nLayers, {0});
+  mNClustersPerROF.resize(nLayers);
+  mTrackletsIndexROf.resize(2, {0});
+}
+
 void TimeFrame::printTrackletLUTonLayer(int i)
 {
   std::cout << "--------" << std::endl