Colleagues,

At the last collaboration meeting, we at Valparaiso University agreed, among
other things, to make a proposal for a graphical display package to display 
events from E614.  The minimal requirements were that --

o The software used for the graphics should be portable to any platform used 
  on the experiment.

o The display should be user friendly and interface with the event analyzer.

o The cost should be reasonable -- i.e., free, if possible.

Paul Nord (Valpo Univ) and I met to outline the features of the event display
package and Paul went on a search to find a suitable graphics package.  After
evaluating two packages which were readily available and free (MESA and ROOT) he
selected the latter.  This is a CERN product and we know of at least one othe
experiment (at RHIC) which will be using this for event graphical display.

Paul then put together a simplified display of of the E614 wire chamber
detector system to illustrate how the display might appear using this package.
The information displayed is not linked to any analysis.  The tracks displayed
are entirely fictitious (to protect the innocent).  And, since there is only 
one such illustration, the  and  buttons do nothing at this
time.  

The goal of this exercise is to share this illustration with you.  Please
take a few minutes (estimate: 10 min.) to look at the illustration and give 
us your comments.  We will use these comments to determine whether this 
approach appears to meet the needs of the experiment for a graphical event 
display package.  If you affirm this approach, we will proceed to implement 
this in detail for E614.  

There are features which we intend to include, among which are:

	1. A "pic" feature to allow the user to get information about wires,
           planes, hits, track kinematics, etc., by using the clicking on 
           them with the mouse and cursor.

      	2. A zoom capability to allow closer inspection of any portion of 
           the detector system.  (Note: the X3D actually provides a zoom
           feature.)

 	3. A header box which will contain event information (run, event, 
           etc.) and some kinematic results from the analysis.

    	4. A link to "the" geometry file for the experiment from which the 
           graphical event display will get the detector geometry values.

	5. A link so that this graphical event display can be called from 
           the analysis codes.

You will no doubt think of other features to be added and your suggestions are
appreciated.

At the collaboration meeting, we said that a 3D display was not required. 
Hence, this display offers several views of the detector in 2D.  However, a
3D display came along "free" so we included it.  The option to rotate the 
views likewise comes along with the package.  

The graphical display software is written in C++.  We will provide FORTRAN
function interfaces for driving the display from analysis routines.

Paul has built the demonstration on gluon.valpo.edu (an alpha workstation)
and he has loaded it all at alph04.triumf.ca.  To view the illustration, you
can use the e614 logon on either gluon.valpo.edu or alph04.triumf.ca from an 
X-terminal and issue the following commnands:

  cd sed
  source setupRoot
  display

Running this over the network can be _slow_ depending on the time of day.
Try for a time when there may be minimal network traffic which will slow down
the transmission.  You can also download the ROOT software on your machine and
then run it locally where it is _very_ fast.  

Please send your comments and suggestions to us as soon as it is convenient.
We are eager to continue to develop this display package if it appears that
this is heading in an acceptable direction.    The summer can be a very
productive time to get this development far along.

What follows are --

o some comments on what you will see when you get the display up and running

o detailed instructions on how to download the root software to your 
  computing platform.  

We look forward to hearing from you soon.

Don and Paul

---------------------------------------------
donald.koetke@valpo.edu
http://www.physics.valpo.edu/faculty/dkoetke/


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BRIEF OVERVIEW OF THE DISPLAY PROGRAM
The buttons  and  do nothing at this time.

Four view options are available from the buttons , , , and .

The  button does the obvious thing.

The axis markers point in the positive directions.  The Z-axis is in the
direction of the beam.  The X-axis is horizontal.  And the coordinate system is
right-handed.  You should always be able to infer the identities of each axis.

The lower buttons toggle the display of the Axis, Tracks, Chambers, Wires, and
Hits.

The display option  is not implemented on most systems.

The display option  should bring up a perspective view of the detector.
Pressing  will bring up a help menu of X3D display options.  X3D will allow
you to click and drag to rotate.

The normal displays can also be rotated in a similar way.

The display graphic windows can be exported in postscript, encapsulated
postscript and gif formats from the menu bar at the top of the window.



PORTING DISPLAY
If you wish to run the display on your own system, the remainder of this
message should guide you through the process of setting up the http://root.cern.ch/root/Version200.html

To use the system, unzip and untar the file. For example:

$ gunzip root_v2.00.HP-UX.B.10.20.tar.gz
$ tar xvf root_v2.00.HP-UX.B.10.20.tar

Set the library path as follows:

>On HP-UX, before executing the interactive module, you must set the library
>path:
>
>      export SHLIB_PATH=$SHLIB_PATH:$ROOTSYS/lib (in bash or ksh)
>      setenv SHLIB_PATH ${SHLIB_PATH}:${ROOTSYS}/lib (in csh or tcsh)
>
>On AIX, before executing the interactive module, you must set the library
>path:
>
>     [ -z "$LIBPATH" ] && export LIBPATH=/lib:/usr/lib
>      export LIBPATH=$LIBPATH:$ROOTSYS/lib
>
>or the equivalent setenv.
>
>On Linux, Solaris, Alpha OSF and SGI, before executing the interactive module,
>you must set the library path:
>
>      export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ROOTSYS/lib
>
>or the equivalent setenv.
>
>On Solaris, in case your LD_LIBRARY_PATH is empty, you should set it like this:
>
>      export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ROOTSYS/lib:/usr/dt/lib
>
>where $ROOTSYS is an environment variable pointing to the ROOT directory. For example, if you use the
>HPUX-10 AFS version (see below), you should set: 
>
>      export ROOTSYS=/afs/cern.ch/na49/library/local/ROOT/hpux10/root  (in bash or ksh)
>      setenv ROOTSYS /afs/cern.ch/na49/library/local/ROOT/hpux10/root   (in csh or tcsh)

Also add the ROOT bin directory to your path:
        set path=($path $ROOTSYS/bin)


GET THE SED SOURCE FILES FROM alph04.triumf.ca/~e614/sed/*

The Makefile may need to be edited for your system.  Consult the
$(ROOTSYS)/test/Makefile for the propper settings of CXX, CXXFLAGS and other
compilation options.  If you have any trouble with this, please contact me for
assistance.  We will want to create a Makefile which will function properly on
all systems that will be used for e614 analysis.  If you do get something to
work without me, please send me a copy so that I can try to integrate it.

Run make:
	make

This should create an executable called "display" which can be invoked from the
command line:
	display

Created for the The Center for Subatomic Research E614 Project Projects Page.

Created by The CoCoBoard.