$Id: History,v 1.2 1999/11/25 14:35:00 japost Exp $
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     Geant4 - an Object-Oriented Toolkit for Simulation in HEP
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                      Category History file
                      ---------------------
This file should be used by G4 developers and category coordinators
to briefly summarize all major modifications introduced in the code
and keep track of all category-tags.
It DOES NOT substitute the  CVS log-message one should put at every
committal in the CVS repository !

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     * Reverse chronological order (last date on top), please *
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Nov  25, 1999   J. Apostolakis  transport-V00-01-01

  transportation.cc: Added protection for the case of a zero step (when there is a field)

  UserSpecialCuts:  Protection to use min range and min kinE only for charged particles


June  9, 1999   J. Apostolakis  transport-01-00-02

  Added a protection so that full relocation is not used for very small moves.


Dec   4, 1998   J. Apostolakis  transport-00-04-01

  The Velocity Vector for Transport in a magnetic field is now set correctly.
    --> previously the scalar velocity was automatically promoted to a 3-vector

Nov  25, 1998  J. Apostolakis   

  Added the direction to  LocateGlobalPointAndUpdateTouchable.

Nov  19, 1998   J. Apostolakis  transport-00-03-04
  Fixes:

  1) The final energy is set equal to the initial energy, because
     the PropagatorInField does not calculate it correctly yet.  NEEDS Fix

  2) If the requested step size is zero and safety is zero,  the
     step is now considered geometry limited.  (This can happen
     if a discrete process tries to take a  step that is very small
     compared to the mean free path.)  Problem observed by Laszlo in EM tests.

  3) PostStepGetInteractionLength now returns DBL_MAX, not kInfinity.


Nov  11, 1998   J. Apostolakis  transport-00-03-03

 Changes to accomodate new interface of Field: 
         (G4PropagatorInField and G4FieldTrack. )

Oct  30, 1998  J. Apostolakis   transport-00-03-02

   In the case of magnetic field, a flag that determines whether the
 geometry limited the step was not set.

---------------------------- next two entries recorded Nov 25th : 

Sep  16, 1998  J. Apostolakis   transport-00-03-01

  Checks whether the particle is out of the world volume
      If so it has exited and must be killed.


Aug  28, 1998  J. Apostolakis 

  The PostStepGetPhysicalInteractionLength has fixed (to return kInf)
  The boolean flags for touchables are now initialised. & Other small fixes ?
  Test code for non-relocating case added (for debugging).



==================================================================================

June 08, 1998   J. Apostolakis  (trans-06-04)

   Corrected Safety computation for the case of the field (adding endpoint
distance instead of curve length.) 

   Added PostStepDoIt method that tries to relocate the particle using
G4ParticleChangeForTransport

   Transportation is no longer a G4ContinuousProcess. 


June 08, 1998   J. Apostolakis  (trans-06-03)

    Modified it to recomputate Safety at the start of a step.  To do this
it uses the previous step's  calculated safety and endpoint.


June 08, 1998   J. Apostolakis  (trans-06-02)

    Modified it to add re-computation of Safety at the endpoint of a step,
when the safety would become negative.  This is done to allow processes
to benefit from a realistic (geometrical) value of the safety.  The
request to do this was from EM physics


June 03, 1998   J. Apostolakis  (trans-06-01)

  The safety we is now generalised to mean the limit of assumption of all
processes. The AlongStepGPIL input value is not the remainder from the
previous step's geometrical safety.

 So the transportation must recalculate the starting point's safety here.
As a zeroeth order approximation we set it to zero.


April 17, 1998  M. Maire      (recorded by John Apostolakis )

A new process, G4UserSpecialCuts, was added to allow the
user an alternative method to set some user cuts.


April 15, 1998  H. Kurasige   (recorded by John Apostolakis )

The transportation does the absolute minimum required to conform to 
the new scheme for ParticleChange: G4VParticleChange is used in signature. 
[ But default G4ParticleChange is still used ]. 

April 14, 1998  John Apostolakis (recorded April 20th).
History file Created
