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1/// \file
2/// \ingroup tutorial_eve
3/// Complex example showing ALICE ESD track visualization.
5/// alice_esd.C - a simple event-display for ALICE ESD tracks and clusters
8/// Only standard ROOT is used to process the ALICE ESD files.
10/// No ALICE code is needed, only four simple coordinate-transformation
11/// functions declared in this macro.
13/// A simple geometry of 10KB, extracted from the full TGeo-geometry, is
14/// used to outline the central detectors of ALICE.
16/// All files are access from the web by using the "CACHEREAD" option.
19/// ### Automatic building of ALICE ESD class declarations and dictionaries.
21/// ALICE ESD is a TTree containing tracks and other event-related
22/// information with one entry per event. All these classes are part of
23/// the AliROOT offline framework and are not available to standard
24/// ROOT.
26/// To be able to access the event data in a natural way, by using
27/// data-members of classes and object containers, the header files and
28/// class dictionaries are automatically generated from the
29/// TStreamerInfo classes stored in the ESD file by using the
30/// TFile::MakeProject() function. The header files and a shared library
31/// is created in the aliesd/ directory and can be loaded dynamically
32/// into the ROOT session.
34/// See the run_alice_esd.C macro.
37/// ### Creation of simple GUI for event navigation.
39/// Most common use of the event-display is to browse through a
40/// collection of events. Thus a simple GUI allowing this is created in
41/// the function make_gui().
43/// Eve uses the configurable ROOT-browser as its main window and so we
44/// create an extra tab in the left working area of the browser and
45/// provide backward/forward buttons.
48/// ### Event-navigation functions.
50/// As this is a simple macro, we store the information about the
51/// current event in the global variable 'Int_t esd_event_id'. The
52/// functions for event-navigation simply modify this variable and call
53/// the load_event() function which does the following:
54/// 1. drop the old visualization objects;
55/// 2. retrieve given event from the ESD tree;
56/// 3. call alice_esd_read() function to create visualization objects
57/// for the new event.
60/// ### Reading of ALICE data and creation of visualization objects.
62/// This is performed in alice_esd_read() function, with the following
63/// steps:
64/// 1. create the track container object - TEveTrackList;
65/// 2. iterate over the ESD tracks, create TEveTrack objects and append
66/// them to the container;
67/// 3. instruct the container to extrapolate the tracks and set their
68/// visual attributes.
70/// \image html eve_alice_esd.png
71/// \macro_code
73/// \author Matevz Tadel
75void alice_esd()
77 const char* esd_file_name = "http://root.cern.ch/files/alice_ESDs.root";
79 TString lib(Form("aliesd/aliesd.%s", gSystem->GetSoExt()));
82 TFile* f = TFile::Open(esd_file_name, "CACHEREAD");
83 if (!f) return;
84 TTree *tree = (TTree*) f->Get("esdTree");
85 tree->SetBranchStatus ("ESDfriend*", 1);
86 f->MakeProject("aliesd", "*", "++");
87 f->Close();
88 delete f;
89 }
90 gSystem->Load(lib.Data());
91 gROOT->ProcessLine(".x run_alice_esd.C");
#define f(i)
Definition: RSha256.hxx:104
#define gROOT
Definition: TROOT.h:406
char * Form(const char *fmt,...)
@ kReadPermission
Definition: TSystem.h:47
R__EXTERN TSystem * gSystem
Definition: TSystem.h:559
A ROOT file is a suite of consecutive data records (TKey instances) with a well defined format.
Definition: TFile.h:54
static Bool_t SetCacheFileDir(ROOT::Internal::TStringView cacheDir, Bool_t operateDisconnected=kTRUE, Bool_t forceCacheread=kFALSE)
Definition: TFile.h:324
static TFile * Open(const char *name, Option_t *option="", const char *ftitle="", Int_t compress=ROOT::RCompressionSetting::EDefaults::kUseCompiledDefault, Int_t netopt=0)
Create / open a file.
Definition: TFile.cxx:3997
Basic string class.
Definition: TString.h:136
virtual int Load(const char *module, const char *entry="", Bool_t system=kFALSE)
Load a shared library.
Definition: TSystem.cxx:1853
virtual Bool_t AccessPathName(const char *path, EAccessMode mode=kFileExists)
Returns FALSE if one can access a file using the specified access mode.
Definition: TSystem.cxx:1294
virtual const char * GetSoExt() const
Get the shared library extension.
Definition: TSystem.cxx:3996
A TTree represents a columnar dataset.
Definition: TTree.h:79
Definition: tree.py:1