doxy: install THtml converter

[u/mrichter/AliRoot.git] / EVGEN / AliGenExtFile.cxx

diff --git a/EVGEN/AliGenExtFile.cxx b/EVGEN/AliGenExtFile.cxx
index 8821335bfacf065b217f8d827aa95b675f2371bd..4d26efa1533962022eb4e4a7214b43c1b9ceb6bd 100644 (file)
--- a/EVGEN/AliGenExtFile.cxx
+++ b/EVGEN/AliGenExtFile.cxx
@@ -31,6 +31,7 @@
 
 #include <Riostream.h>
 
+#include "AliLog.h"
 #include "AliGenExtFile.h"
 #include "AliRunLoader.h"
 #include "AliHeader.h"
@@ -43,12 +44,17 @@
 #include <TTree.h>
 
 
+using std::cout;
+using std::endl;
+using std::map;
+
 ClassImp(AliGenExtFile)
 
 AliGenExtFile::AliGenExtFile()
     :AliGenMC(),
      fFileName(0),
-     fReader(0)
+     fReader(0),
+     fStartEvent(0)
 {
 //  Constructor
 //
@@ -59,7 +65,8 @@ AliGenExtFile::AliGenExtFile()
 AliGenExtFile::AliGenExtFile(Int_t npart)
     :AliGenMC(npart),
      fFileName(0),
-     fReader(0)
+     fReader(0),
+     fStartEvent(0)
 {
 //  Constructor
     fName   = "ExtFile";
@@ -80,7 +87,7 @@ void AliGenExtFile::Init()
     if (fReader) fReader->Init();
 }
 
-    
+//___________________________________________________________
 void AliGenExtFile::Generate()
 {
 // Generate particles
@@ -91,11 +98,27 @@ void AliGenExtFile::Generate()
   Double_t time = 0.;
   Double_t p[4];
   Float_t random[6];
-  Int_t i = 0, j, nt;
+  Int_t i=0, j, nt;
   //
   //
   if (fVertexSmear == kPerEvent) Vertex();
 
+  // Fast forward up to start Event
+  for (Int_t ie=0; ie<fStartEvent; ++ie ) {
+    Int_t nTracks = fReader->NextEvent();      
+    if (nTracks == 0) {
+      // printf("\n No more events !!! !\n");
+      Warning("AliGenExtFile::Generate","\nNo more events in external file!!!\nLast event may be empty or incomplete.\n");
+      return;
+    }
+    for (i = 0; i < nTracks; ++i) {
+      if (NULL == fReader->NextParticle())
+       AliFatal("Error while skipping tracks");
+    }
+    cout << "Skipping event " << ie << endl;
+  }  
+  fStartEvent = 0; // do not skip events the second time 
+
   while(1) {
     Int_t nTracks = fReader->NextEvent();      
     if (nTracks == 0) {
@@ -133,14 +156,87 @@ void AliGenExtFile::Generate()
       fReader->RewindEvent();
     }
 
+    //
+    // Stack selection loop
+    //
+    class SelectorLogic { // need to do recursive back tracking, requires a "nested" function
+    private:
+       Int_t idCount;
+       map<Int_t,Int_t> firstMotherMap;
+       map<Int_t,Int_t> secondMotherMap;
+       map<Int_t,Bool_t> selectedIdMap;
+       map<Int_t,Int_t> newIdMap;
+       void selectMothersToo(Int_t particleId) {
+        Int_t mum1 = firstMotherMap[particleId];
+          if (mum1 > -1 && !selectedIdMap[mum1]) {
+             selectedIdMap[mum1] = true;
+             selectMothersToo(mum1);
+          }
+          Int_t mum2 = secondMotherMap[particleId];
+          if (mum2 > -1 && !selectedIdMap[mum2]) {
+             selectedIdMap[mum2] = true;
+             selectMothersToo(mum2);
+          }
+       }
+    public:
+      SelectorLogic():idCount(0), firstMotherMap(), secondMotherMap(), selectedIdMap(), newIdMap() {}
+      void init() {
+          idCount = 0;
+       }
+       void setData(Int_t id, Int_t mum1, Int_t mum2, Bool_t selected) {
+          idCount++; // we know that this function is called in succession of ids, so counting is fine to determine max id
+          firstMotherMap[id] = mum1;
+          secondMotherMap[id] = mum2;
+          selectedIdMap[id] = selected;
+       }
+       void reselectCuttedMothersAndRemapIDs() {
+          for (Int_t id = 0; id < idCount; ++id) {
+             if (selectedIdMap[id]) {
+                selectMothersToo(id);
+             }
+          }
+          Int_t newId0 = 0;
+          for (Int_t id = 0; id < idCount; id++) {
+             if (selectedIdMap[id]) {
+                newIdMap[id] = newId0; ++newId0;
+             } else {
+                newIdMap[id] = -1;
+             }
+          }
+       }
+       Bool_t isSelected(Int_t id) {
+          return selectedIdMap[id];
+       }
+       Int_t newId(Int_t id) {
+          if (id == -1) return -1;
+          return newIdMap[id];
+       }
+    };
+    SelectorLogic selector;
+    selector.init();
+    for (i = 0; i < nTracks; i++) {
+       TParticle* jparticle = fReader->NextParticle();
+       selector.setData(i,
+             jparticle->GetFirstMother(),
+             jparticle->GetSecondMother(),
+             KinematicSelection(jparticle,0));
+    }
+    selector.reselectCuttedMothersAndRemapIDs();
+    fReader->RewindEvent();
+
     //
     // Stack filling loop
     //
     fNprimaries = 0;
     for (i = 0; i < nTracks; i++) {
-       TParticle* jparticle = fReader->NextParticle();
-       Bool_t selected = KinematicSelection(jparticle,0); 
-       if (!selected) continue;
+       TParticle* jparticle = fReader->NextParticle();
+       Bool_t selected = selector.isSelected(i);
+       if (!selected) {
+          continue;
+       }
+       Int_t parent = selector.newId(jparticle->GetFirstMother());
+//       printf("particle %d -> %d, with mother %d -> %d\n", i, selector.newId(i), jparticle->GetFirstMother(), parent);
+
        p[0] = jparticle->Px();
        p[1] = jparticle->Py();
        p[2] = jparticle->Pz();
@@ -166,7 +262,6 @@ void AliGenExtFile::Generate()
            time = fTime + jparticle->T();
        }
        Int_t doTracking = fTrackIt && selected && (jparticle->TestBit(kTransportBit));
-       Int_t parent     = jparticle->GetFirstMother();
        
        PushTrack(doTracking, parent, idpart,
                  p[0], p[1], p[2], p[3], origin[0], origin[1], origin[2], time,
@@ -178,8 +273,8 @@ void AliGenExtFile::Generate()
     } // track loop
 
     // Generated event header
-    
-    AliGenEventHeader * header = new AliGenEventHeader();
+    AliGenEventHeader * header = fReader->GetGenEventHeader();
+    if (!header) header = new AliGenEventHeader();
     header->SetNProduced(fNprimaries);
     header->SetPrimaryVertex(fVertex);
     header->SetInteractionTime(fTime);
@@ -192,6 +287,7 @@ void AliGenExtFile::Generate()
   CdEventFile();
 }
 
+//___________________________________________________________
 void AliGenExtFile::CdEventFile()
 {
 // CD back to the event file