The utility provides 3 options:

• DAQ file browsing
• Event pool monitoring
• GEANT Geometry file browsing

1. DAQ file browsing

To browse some daq file just open it via either via "File"->Open" or "Open" tool button and click "single event play" or "instant play" buttons

2. Event pool monitoring

If no daq file has been opened one can just click "single event play" or "instant play" buttons.
If some daq file had been opened, to switch to the "event pool" check the "Event pool" from the "File" menu.

3. Creating the selected event image file

• save the image of the selected event with the various image formats;
• create the image file for each new event automatically;
• create the image for each new frame (event / event projection) automatically (movie option)

3.1.Create the image of the selected event

• Interrupt the event "polling" by depressing the "Play Event" button of the Event Panel if needed;
• Stop the coordinate system rotation by entering "0" value for the "rotation speed" if needed
• Open the event pool file with the event selected via
  File -> Open menu.
  Please, take in account that online event pool is a NFS mounted directory with the fixed name "/evp/a". This directory has a bunch of the subdirectories one subdirectory per run where the name of the directory matches the "run number".

         
  [rts03] /evp/a/> ls /evp/a
  8139064  8146048  8147098  8150047  8153026  8156042  8158020
  8143060  8146049  8147099  8150048  8153027  8156043  8158021_DELETE
  8144010  8146050  8147100  8150049  8153028  8156044  8158022
  8144011  8146051  8147101  8150050  8153029  8156045  8158023
  

  Each "run number" directory" contains a bunch of the event files, one event file per event, where the file name is the "event number".

         
  [rts03] /evp/a/> ls /evp/a/8156039
  0    122  147  171  196  22   244  269  293  317  341  366  390  414  52  77
  1    123  148  172  197  220  245  27   294  318  342  367  391  415  53  78
  10   124  149  173  198  221  246  270  295  319  343  368  392  416  54  79
  100  125  15   174  199  222  247  271  296  32   344  369  393  417  55  8
  101  126  150  175  2    223  248  272  297  320  345  37   394  418  56  80
  102  127  151  176  20   224  249  273  298  321  346  370  395  419  57  81
  103  128  152  177  200  225  25   274  299  322  347  371  396  42   58  82
  

  This means to draw the selected event one has to open the file

         
          /evp/a/<run_number>/<event_number>
  

• Set the desired scale, zoom and orientation with the OpenGL windows controls (see: Offline Display page and
• Save it using the "File" -> Save As" menu of the OpenGL widget (please don't mess it with the "File -> Save" menu of the "Event Control" (this is odd and will be fixed) to be fixed soon)

4. Event components

• tracks - track information is provided by L3 reader via its "local_track". The track helix parameters are used to create the 3D polyline to represent the track. The track color is defined by the dedx member of the l3 "local_track" structure.
  One can select any track with the mouse pointer. (See "Geometry browser" for the GUI term explanation). At this point display is to highlight the selected track and pop up the label with the track "dedx" and "pt" values.
• Emc hits - the emc barrel tower ADC values are provided by emcReader. In addition the "Event Display" takes in account the current barrel emc status information. The current status file is available from event pool, namely, from /evp/a/bemcStatus.txt file.
  The tower size if defined by (adc-pedestal) value for each tower with (adc-pedestal) >3. The tower color is defined as follows:

             
            colorCode = (adc-pedestal) 
            // If edep less then MIP (~300 MeV), 60GeV <-> 4096 ADC counts
            if (colorCode < 20)
                 colorResponce = kBlue;
             // If edep large then MIP but less then 1 GeV
            else if ( colorCode < 68) )
                 colorResponce = kGreen;
            // If between 1 GeV and lowest HT threshold (4 GeV for Run7)
               else if ( colorCode < 256) )
                 colorResponce = kYellow;
            // If above lowest HT thershold
              else colorResponce = kRed;
  

  One can select any tower with the mouse pointer. (See "Geometry browser" for the GUI term explanation). At this point display is to highlight the selected tower and pop up the label with

             
          SoftId;
          PatchMaskHT;   /* Patch unmasked in HT? */
          PatchMaskSum;  /* Patch unmasked in sum? */
          TriggerPatch;  /* TriggerPatch */
   

5. GEANT Geometry file browsing.

Even though it is still possible to use the "Online Event Display" to browse the root file with GEANT detector geometry definition, one is recommended to use the dedicated utility "Geometry Browser". The icon to launch the utility is available from the "l3user" desktop. The Detector geometry browser documention can be found on Web page http://www.star.bnl.gov/STAR/comp/vis/GeometryBrowser.pdf.

The "STAR Geometry browser" is available from any account of any RCF machine.

6. High quality 3D OpenGL window

You can decay the half of the detector view to reveal its insight with the coordinate plane described by "STAR Detector Geometry Browser