class THaBigBite: public THaSpectrometer

 THaBigBite

 Base class for general purpose bigbite detector (spectrometer)



 Author: Jin Huang <mailto:jinhuang@jlab.org>   July 2007
        Base on work of Olivier Gayou, AGen Lib, and Ole Hansen
    Modify History:
      Jan 2008    Jin Huang <mailto:jinhuang@jlab.org>
          add support to new MWDC class
      Jan 2008    Jin Huang <mailto:jinhuang@jlab.org>
          add new child class THaOptics



This is a base class for the Hall A BigBite spectrometer (BB).
Ready for AddDetector() of THaTriggerPlane, THaMWDC, TreeSearch::MWDC, THaBBTotalShower



SPECIAL CONFIGURATIONS of BB (e.g. more detectors, different
detectors) can be supported in on e of three ways:

1. Use the AddDetector() method to include a new detector
in this apparatus.  The detector will be decoded properly,
and its variables will be available for cuts and histograms.

2. Write a derived class that creates the detector in the
constructor. An example is THaBigBiteTpMwdc specially
designed for hardron package.



TECHNICALLY, THaBigBite is a standard THaSpectrometer with support of

1.Optics class THaOptics and its heritage classes.
For detailed infomation about THaOptics support, please see documentation of THaOptics

2.Special requirements of old AGen version of MWDC (THaMWDC), including reorder
of process and read out of environment variables.

Environmental variable USE_AGEN_MWDC controls whether THaMWDC is supported.
if USE_AGEN_MWDC=1, then SWITCH_RECONSTRUCT_ORDER will be turned on, as well as
a collection of supportive functions & variables will be defined.

In the case of SWITCH_RECONSTRUCT_ORDER=1 :
Reconstruct process is different from standard THaSpectrometer. That's
Loop over all THaNonTrackingDetectors and call their CoarseProcess() methods.
Loop over all THaTrackingDetectors and call their CoarseTrack() methods.
Loop over all THaNonTrackingDetectors and call their FineProcess() methods.
Loop over all THaTrackingDetectors and call their FineTrack() methods.
In this way, THaMWDC could get hit info from THaTriggerPlane, which will
dramatically speed track reconstruction.
Environmental Variable SWITCH_RECONSTRUCT_ORDER controls
whether or not to change order of steps in Reconstruct()