From a55f626d670e9dc7afee0ba7e0a60ea05c8d5228 Mon Sep 17 00:00:00 2001
From: richterm <richterm@f7af4fe6-9843-0410-8265-dc069ae4e863>
Date: Wed, 11 Jun 2008 11:23:29 +0000
Subject: [PATCH] updated documentation

---
 HLT/BASE/AliHLTModuleAgent.h | 16 +++++++++-------
 HLT/sim/AliHLTSimulation.h   | 36 +++++++++++++++++++++++++++++++++++-
 2 files changed, 44 insertions(+), 8 deletions(-)

diff --git a/HLT/BASE/AliHLTModuleAgent.h b/HLT/BASE/AliHLTModuleAgent.h
index 49c9a4a262a..e8db15bfcaa 100644
--- a/HLT/BASE/AliHLTModuleAgent.h
+++ b/HLT/BASE/AliHLTModuleAgent.h
@@ -46,8 +46,8 @@ class AliHLTModulePreprocessor;
  * @note There must not be more than one agent per module/library.
  *
  * If a run loader is available, reconstruction is performed on simulated
- * data as part of <tt>AliSimulation</tt>, if the raw reader is present on
- * raw data as part of <tt>AliReconstruction</tt>. The configurations
+ * data as part of <tt>AliSimulation</tt>, if only the raw reader is present,
+ * on raw data as part of <tt>AliReconstruction</tt>. The configurations
  * can adapt to the two cases.
  *
  * All HLT component libraries are loaded on demand through the HLT steering
@@ -70,8 +70,8 @@ class AliHLTModulePreprocessor;
  *       Create HLT configuration forming an HLT analysis chain.            <br>
  *       Reconstruction of raw data or simulated data from digits needs
  *       usually different configurations. If a run loader is available,
- *       reconstruction is performed on simulated data, on raw data if the
- *       raw reader is present.
+ *       reconstruction is performed on simulated data, on raw data if Run
+ *       loader is NULL and only the raw reader present.
  *
  * - @ref GetReconstructionChains                                           <br>
  *       Configurations run during event reconstruction.                    <br>
@@ -158,9 +158,11 @@ class AliHLTModuleAgent : public TObject, public AliHLTLogging {
    * AliHLTConfigurationHandler. The agent can adapt the configurations
    * to be registered to the current AliRoot setup by checking the
    * runloader and the raw reader. <br>
-   * Run loader and raw reader are usually not present at the same time.
-   * If a run loader is available, reconstruction is performed on simulated
-   * data, if the raw reader is present on raw data. The configurations
+   * The presence of Run loader and raw reader determines the mode of the
+   * HLT reconstruction. If a run loader is available, reconstruction is
+   * performed on simulated data, a raw reader might be available in that
+   * case also. When running embedded into AliReconstruction, the Run loader
+   * is always NULL and the raw gives access to data. The configurations
    * can adapt to the two cases.
    *
    * @param handler   [in] the configuration handler
diff --git a/HLT/sim/AliHLTSimulation.h b/HLT/sim/AliHLTSimulation.h
index eead445c825..5c661749df6 100644
--- a/HLT/sim/AliHLTSimulation.h
+++ b/HLT/sim/AliHLTSimulation.h
@@ -31,7 +31,41 @@ class AliRawReader;
 
 /**
  * @class AliHLTSimulation
- * Base class of HLT data processing simulations.
+ * Plugin for HLT reconstruction embedded into <tt>AliSimulation</tt>.
+ *
+ * HLT has a special role in the normal data flow  of simulation and
+ * reconstruction. Since the HLT reconstruction and analysis runs on-line
+ * on the HLT farm, the raw data produced by HLT as a detector contains
+ * already reconstructed events. Consequently, the HLT response has to be
+ * simulated as well as the data of all other detectors. Since the detector
+ * data is needed, the HLT simulation is run at the end of AliSimulation.
+ * As a matter of fact, HLT always reconstructs data, <em><b>HLT simulation
+ * </b></em> means <em><b>HLT reconstruction embedded into AliRoot</b></em>.
+ *
+ * The AliHLTSimulation class is the steering class called from AliSimulation.
+ * An instance of AliHLTSystem is used to run the chains defined by the
+ * available libraries or a configuration macro.
+ *
+ * The libraries to be loaded can be specified as an option to AliSimulation.
+ * <pre>
+ * AliSimulation sim;
+ * sim.SetRunHLT("libAliHLTSample.so");
+ * </pre>
+ * will only load <tt>libAliHLTSample.so</tt>
+ *
+ * Other available options:
+ * \li loglevel=<i>level</i>                                            <br>
+ *     logging level for this processing, default level is 0x79 filtering
+ *     out everything below level 'warning'. 0x7c allows info messages as
+ *     well, 0x3f is the highest loglevel.
+ * \li alilog=off                                                       <br>
+ *     disable redirection of log messages to AliLog class
+ * \li config=<i>macro</i>                                              <br>
+ *     configuration macro: normal ROOT macro defining HLT component
+ *     configurations by means of AliHLTConfiguration.
+ * \li chains=<i>configuration</i>                                      <br>
+ *     comma separated list of configurations to be run during simulation
+ *
  */
 class AliHLTSimulation : public TObject {
  public:
-- 
2.43.0