ReleaseNotes.md

  in Geant4Output2LCIO.cpp

* A.Sailer 
- Add missing scope to /DD4hep/Factories.h, to not force everyone to use using namespace

* F.Gaede: 2015-07-15
- changed type in SurfaceList and SurfaceMap from Surface to ISurface
- added methods length_along_u/v() to ISurface
- moved setting of CMAKE_CXX_FLAGS (if DD4HEP_USE_CXX11) from DD4hep.cmake to CMakeLists.txt

* 2015-07-11 M.Frank
-  added starter docs dd4hepStartersGuide.pdf

*** **Important** ***
  **Before updating, backup your existing and working checkout. Though I was running 
  the basic tests, there may be unchecked corners of the software.**

Notes:
- Backwards compatibility mode for the usage of ROOT 5 and ROOT 6 alternatively.
- For ROOT 6 the Gaudi PluginService is used and added to the distribution.
- dd4hep is distributed with a licence. See $DD4hepINSTALL/LICENSE for details.
- In the doc area the $DD4hepINSTALL/doc/CREDITS file everybode should add her/his 
  name, if contributed significantly.
- Unfortunately this meant to add/change the headers of all files and give a 
  pointer to the licence file. If I accidentally changed the author name, please
  chagne it back.
- The plugin factory declaration statements were changed to accomodate both
  ROOT 5 and ROOT 6 and to keep the number of 'ifdef' statements at a minimum.
- TODO: Properly change the cmake scripts to accomodate for ROOT 6 and the 
  automatic switch when building dd4hep. 
- For reference reasons: this commits is revision 1812 + 1813 (DDDetectors)

# v00-13  
* 2015-07-03 F.Gaede
- updated doxygen for detector rec::DetectorData structs and usage in convertToGear

* 2015/07/02 Nikiforos Nikiforou
- Added isRadiator() helper function in DDCore/XML/XMLDetector.h/cpp 
  Mirroring functionality of isSensitive() and used in geometry drivers
  e.g. to calculate total absorber thickness
  
- Extended LayeredCalorimeterStruct in DDRec/DetectorData.h to include 
  additional parameters required by Pandora:
  - inner_phi0 (e.g. alignment for inner symmetry)
  - outer_phi0 (e.g  aligment for outer symmetry)
  - NOTE: phi0 still remains but is deprecated
  - gap0 (e.g stave gap along r-phi)  
  - gap1 (e.g middle stave gap along z)
  - gap2 (reserved for future use)

*  2015-06-29 A.Sailer
 - always store lcio collections, even if they are empty in Geant4Output2LCIO (DDG4/ddsim)


* 2015-06-29 F.Gaede
- changed env scripts to prepend to library pathes (dd4hep and dependant packages)
   - using a newer lcgeo version than the one provided in ilcsoft can simply
        be done w/ source ./bin/thislcgeo.sh 
	      
# v00-12  
* 2015/06/17 Markus Frank
- Add possibility to block access to constants by name from Detector.
  Functionality enabled by a constant named "Detector_InhibitConstants" with value "1", "True", "Yes".
  Test: geoDisplay -compact file:../DD4hep.trunk/examples/ClientTests/compact/InhibitConstants.xml 

- Add DetectorHelper handle object to easily access the sensitive detector object of a detector
  using either the subdetector name or the detector element (or one of its children).
  See: dd4hep/DetectorHelper.h
  Test: ``` 
  geoPluginRun -input file:../DD4hep.trunk/examples/CLICSiD/compact/compact.xml \
                     -plugin CLICSiD_DetectorHelperTest  \
         optional:  -<detector-name (default:SiVertexEndcap)>  [Note the '-'!!!] 
         ```

- Check when adding new sub-detector detector elements if a given one already exists.
  if yes: exception.
  Test: `geoDisplay -compact file:../DD4hep.trunk/examples/ClientTests/compact/DuplicateSysID.xml`


* A. Sailer
- DDSegmentation: Added function cellDimension which returns the dimension of any given cell

* S.Lu:
- Added a switch for BirksLaw to Geant4StepHandler. 
  For backward compatable, by default, do not apply BirksLaw, and apply BirksLaw with call 'doApplyBirksLaw()'.
  added optional Geant4ScintillatorCalorimeterAction
- Added one 'Geant4ScintillatorCalorimeterAction' into DDG4 plugins Geant4SDActions for  scintillator to take 
  Geant4 BirksLaw effect as sensitive detector active layer.

* F.Gaede
- added SurfaceManager class that holds maps of surfaces for 
  "world","tracker","calorimeter","passive" and all individual subdetectors
    - to be used in reconstruction code where a lookup from cellID
      to corresponding surface is needed
    - needs plugin "InstallSurfaceManager" to be in the compact file
    - access via:  
      SurfaceManager surfMan = *description.extension< SurfaceManager >() ;
      const SurfaceMap& surfMap = *surfMan.map( "world" ) ;
- renamed old SurfaceManager to SurfaceHelper

- added method: Volume createPlacedEnvelope()
  - to be used in all LC detector drivers to create a placed envelope volume
    rest of the detector is then instantiate in this volume

- added BooleanShape plugin for creating generic boolean
  shapes (subtraction, union or intersection )
   - to be used for envelope definition in xml

   - added new build_type: BUILD_ENVELOPE 
      - can be used to visulize envelopes only (geoDisplay, teveDisplay,...)

* 2015/05/22 Nikiforos Nikiforou
- Fixed bug in DDG4/lcio/LCIOConversions.cpp, which stored only the PDG of the primary particle 
  in multiple particle contributions in SimCalorimeterHits instead of both the primary and secondary PDGs.


* 2015/05/13 Markus Frank
- Fix bug in DDG4, which forced DDG4 to exit if a property from the Geant4 prompt could
  not be set. No an error message is printed and the prompt is returned to the user.
  (Bug submitted by A. Sailer)

* 2015/05/11 Andre Sailer
- CMake updates:
  - Split libraries into components: use find_package(dd4hep COMPONENTS <component> [...] )
    to find the components you need.
  - At the moment there are these components are sensible to link against: DDRec, DDG4, DDEve, DDSegmentation
  - To link against the librarie use either dd4hep_COMPONENT_LIBRARIES or dd4hep_<COMPONENT>_LIBRARY,
    where <COMPONENT> needs to be replaced by the UPPER case name of the component

* 2015/05/09 Markus Frank
- Allow to access detectors by type from description.
  - The sensitive type of a detector is set in the 'detector constructor'.
  - Not sensitive detector structures have the name 'passive'
  - Compounds (ie. nested detectors) are of type 'compound'
- Dump detector types using plugin:

         geoPluginRun -plugin DD4hepDetectorTypes -input <compact-file>

* 2015/03/12 Markus Frank
- Add support for ellipsoids in gdml/description and geant4 conversion.
- Allow to include files with environment variables from compact notation.

* 2015/03/09 Markus Frank
- Finalize move to geant4 version 10, started by A.Sailer
- Add non-isotrop particle generator in DDG4 (request P.Kostka)
- Isolate ROOT plugin manager as start to move to ROOT 6

# v00-11
* F.Gaede
- DDDetectors
  - new Package containing generic dd4hep detector palette (MF)
  - added 'dimension' argument to dd4hep_SiTrackerBarrelSurfacePlugin (FG)
    to handle pixel and strip detectors 

- DDRec (Frank Gaede)
  - added simple data structs in DDRec/DetectorData.h
    providing interface needed for GEAR:
  - added plugin for creating GEAR file for ILD
  - Extended IDDecoder to give access to layer, system and barrel/endcap information. (CG)
    IDDecoder is now independent of Readout object, instead it finds the correct
    readout based on the cellID / position
  - fixed surface implementations: removed inline virtual functions
  - added methods:
    VolSurface::length_along_u()
    VolSurface::length_along_v()
    Surface::volumeOrigin()
    CylinderSurface::center()
    ICylinder::center()  

- DDG4 (Markus Frank)
  - Fix Geant4 Primary input conversion
  - Fix LCCollectionVec for LCIO output
  - fixed units for MCParticle output (FG)
  - fixed generator status: set to 0 if (FG)
    particle created in simulation
  - Add cylindrical tracking volume to particle handler
  - More modular user particle handling with example Geant4TCUserParticleHandler
  - fixed charge (don't devide by three) (FG)
  - fixed logic for writing out MCParticles: (FG)
    - don't write particles created in calo
      unless scattered back into tracker)
    - don't write particles created in tracker
      if below MinimalKineticEnergy ( Geant4ParticleHandler)
  - Added HepMC ascii reader
  - added simply main program 'dd_sim' to run  (FG)
    a DDG4 based simulation with xml configuration files
  - change TrackerCombine SD to use energy weighted positions
  - added utility to dump generated files: scripts/dumpDDG4.C
  - fixed dictionaries for map iteration on MacOS in python (FG)
    -> added operators ==/!= for map<>::iterator
  - added component to allow the setup of the magnetic field tracking in Geant4 from python

- DDCore (Markus Frank)
  - fixed Detector el-mag. field converter 
  - add generic surface installers 
  - allow for string constants in description define section
  - added arguments for surface plugins

- DDSegmentation (FG) :
  - fixed compiler warning w/ left shift count >= width of type 
  - fixed wrong type string "CartesianGridXY"
  - added CartesianGridYZ
  - Implementation of a Polar R-phi segmentation  (MP)
  
 - examples 
  - add new test MiniTel(escope) to ClientTests (MF)
  - moved old obsolete examples to attic
  - add new example: LHeD_tracker (MF) 
  - add new example: SimpleDetector (FG)
    (ILD like VXD and SIT )
    
- CMake:
  - made DD4HEP_USE_BOOST an option flag (FG)
  - added dd4hepG4 library dependence to DDEve (MF)
  - disable dot -> have simpler (and faster) inheritance graphs w/ Doxygen
  - fixed missing search field in Doxygen doc (FG)
  - include boost automatically if build with Geant4

 
- Documentation
  - improved Doxygen documentation (MF)
  - added manual for DDRec (FG)
  - new version of the dd4hep manual (MF)
  - fixed code formating with emacs style:
    ./doc/format_code.sh

- removed subpackages ( moved to https://svnsrv.desy.de/public/aidasoft/DD4hep/attic ):
      DDExamples_obs/
      DDSense/
      examples/ILDExDet/
      examples/ILDExSimu/
      examples/firstExample/
      examples/noviceN04/

- enabled testing in nightly builds with cmake, ctest and cdash (FG)

- plus many small bug fixes  (use svn log for details )

* 2014/09/26 Markus Frank
- Quite some effort to improve the doxygen documentation.
  The current revision is can be found at:
  https://cern.ch/frankm/DD4hep/html/index.html

* 2014/02/06 Markus Frank
- DDDetectors: Add example surface plugin with arguments.
    - example code: DDDetectors/src/SurfaceExamplePlugin.cpp
    - compact:
```   
       <plugin name="DD4hep_SurfaceExamplePlugin">
          <argument value="SiTrackerBarrel"/>
          <argument value="aa=1*mm"/>
          <argument value="bb=2*cm"/>
          <argument value="cc=3*m"/>
       </plugin>
```

    - output:
    
```cpp
    SurfaceExamplePlugin: argument[0] = SiTrackerBarrel value = -1
    SurfaceExamplePlugin: argument[1] = aa=1*mm value = 0.1
    SurfaceExamplePlugin: argument[2] = bb=2*cm value = 2
    SurfaceExamplePlugin: argument[3] = cc=3*m value = 300
```

* 2014/08/15 Markus Frank
- DDG4: Impreoved LCIO handling for DDG4
- DDG4: Input handling:
  - LCIO input file reading with multiple *independent* inputs
    to support overlay, multiple interactions, etc.
  - Primary verex smearing independent for each input
  - Primary vertex boosts independent for each input
- DDG4: Output handling
  - MC Particle handling
  - Improved MC truth handling for produced Hits.
    Still needs revisiting.

# v00-10      
*  Frank Gaede
- fixed version numbers and release notes for release v00-08 and v00-09
  ( both have the wrong version number for the libraries 0.7 !)
- added ./doc/prepare_a_release.howto
- added new method to BitField64: setValue(unsigned lowWord, unsigned highWord )
 - added some simple unit tests for BitField64


* 2014/08/15 Markus Frank
- DDG4 Add possibility for user hook to the particle handler +
  Data member to store additionbal particle data for the
  output stage.
- Allow to display MC particles in DDEve
  Add small help file describing how to start DDEve.
  doc/DDEveManual.pdf
- Update CLICSiD Example.

# v00-09      
* 2014/08/07 Markus Frank
- DDG4: First version to support MC truth in DDG4 including 
  particle filtering to optimize the size of the MC record.
- DDG4 fix SimpleCalorimter sensitive action and properly support
  hit aggregations.
- DDEve smaller modifications to support DDG4IO if dd4hep was 
  built with the Geant4 option ON.

# v00-08
- Some minor fixes:
  - made compatible with older geant4 versions (9.5)
  - add Bitflag to store CellID1 in SimCalorimeterHit collections
  - fix position conversion from Geant4 to ROOT
  - add cellID determination to SensitiveAction
  - ...


* Andre Sailer, 2014-07-17
- Unify cmake option variables, small cmake corrections
- Change options `_WITH_` to `_USE_`
- Print Warning that variables with `_WITH_` are deprecated
- Change Defintions to `_USE_` as well
- Add REQUIRED to find_package geant4 and xercesc if they are turned on
- Updated documentation
- Updated ILDExDet example

* Christian.Grefe, 2014-07-15
- Made DDSegmentation optionally a stand-alone package
  create DDSgementationConfig.cmake when build as part of dd4hep

* Markus Frank, 2014-07-02
- add LCIO conversions from DDSim - sensitive detectors 
  can now simply instantiate LCIO Sim hits
  
* 2014/06/30 Markus Frank
- DDG4: Support user (context-) extensions for Geant4.
  User contexts are availible for events and runs. The contexts
  are accessible from the Geant4Context meber of each Geant4Action,
  the base class for all processing entities.
   - Adding a context:
```
      context()->event().addExtension(pointer_to_object, typeid(TYPE), 0);
      or 
      context()->event().addExtension<TYPE>(pointer_to_object);
      In the first case the object is NOT DELETED at the end of the event.
      In the second case the object is deleted.
```      
    - Accessing the context:
```    
          TYPE* ctx = context()->event().extension<TYPE>(false);
      The boolean argument indicates if an exception should be thrown
      if the extension is not present ie. here no exception.
```      
- DDCore: adjust a few print statements.

* 2014/06/27 Markus Frank
- Separate XML loading from Detector implementation.
- New package: DDEve: a bit more sophisticated TEve specialization
- To start use examples/CLICSiD/compact/DDEve.xml
- DDEve can interface currently to ROOT files created by DDG4.
- An example data file is provided as well in:
- examples/CLICSiD/compact/CLICSiD_events.root
- Documentation is lacking a bit....
- start the display with: `$> root.exe ${DD4hepINSTALL}/examples/DDEve/DDEve.C`


* 2014/06/19 Frank Gaede
- replaced TGeoUnits.h by  DD4hepUnits.h
- renamed namespace tgeo to dd4hep -> users need to replace tgeo::mm by dd4hep::mm


* 2014/06/12 Frank Gaede
- changed default unit for angles to be radians   (tgeo::rad = 1.)
- enforce usage of units from TGeoUnits.h in xml expression evaluators
- convert to degrees for angles in TGeoShapes constructors
- NB: there is one inconsistency left here:  angles returned
  from TGeoShapes are already in degrees, this is the one
  case where a quantity returned from dd4hep/TGeo does not have the default
  units - thus one should not write
  
 ` double phi = coneSeg.Phi1() / tgeo::rad ;`
 
  but rather
  
  `double phi = coneSeg.Phi1() * tgeo::deg ;`


* 2014/06/03 Markus Frank
- Provision for ROOT persistency for dd4hep detector descriptions:
  Create Cint dictionary for dd4hepCore by default when building the library.
  For the time being the area of DDSegmentation is left out, since these
  objects require changes due to the handling of references and template
  specializations. Besides these, dd4hep detector descriptions can be
  saved and read-back directly to/from ROOT files - which may improve
  a lot the startup time of processes.

- The DDG4 dictionary is created by default when building the library.
  When importing DDG4 from python only the dd4hepCore dd4hepG4 libraries
  must be present. It should no longer be necessary to compile the
  necessary AClick on the fly.

- Investigations on wirframe drawing:
  Wireframes are a property of the scene graph. You can toggle to wireframe
  using the 'w' key on the keyboard. Other representations are 
  'r': Solid view
  't': Solid + wireframe view.
  This information is accessible from the help menu of the ROOT OGL widget.

# v00-07
* 2014/05/28 Markus Frank

- Several fixes and improvements in DDG4
  - Cache output levels in Geant4Kernel object
  - Add shell handler to measure energy escape e.g. in calorimeters
- Fix bug in Polycone shapes concerning angles.
      **IMPORTANT: If you forked the repository examples/CLICSiD
      your PolyconeSupport does not work anymore, because the angles
      were given in degrees. They should be given in radians!**

* 2014/05/21 Markus Frank
- Fix material creation from XML
    JIRA bug: dd4hep -  DDFORHEP-4
    https://sft.its.cern.ch/jira/browse/DDFORHEP-4
    using <composite> in material xml files results in wrong material properties

- Fix JIRA bug: dd4hep -   DDFORHEP-3
    https://sft.its.cern.ch/jira/browse/DDFORHEP-3
   Recursive assemblies result in error in TGeo geometry
    Bug results in errors when closing the geometry like:
    "Error in <TGeoVoxelFinder::SortAll>: Wrong bounding box for volume SIT_assembly"

- Provision to store survey constants to the DetElement as an extension
    for Alignment calculations (priv. comm. C.Parkes)

- Fix bug in expression evaluation of angles.
    All detector constructors receive angles in "rad". No correction 
    from degree to rad should be necessary.

* 2014/05/21 Frank Gaede
- add MaterialManager class providing
  - access to materials at any point or on straight
    line between two points
  - creation of material with averaged properties (A,Z,rho,x0,Lambda)
 
- added utility print_materials to print material properties along  
  a straight line between two points including integrated radiation and 
  interaction lengths (useful for debugging geometries and materials)
 
- use avaeraged material for Surfaces where the thickness extends
  beyond the volume boundaries
   - introduced new simple data class MaterialData for this       
    

- known issues
   - materials don't work for detectors with assemblies in assemblies
        as the TGeo navigation dose not seem to work:
	Error in <TGeoVoxelFinder::SortAll>: Wrong bounding box for volume SIT_assembly
        -> ROOT bug or feature ?

    - using <composite/> in compound materials results in incorrect material properties
       see ILDExDet/compact/materials Polysterene as example


* 2014/05/06 Frank Gaede
- DDSurfaces/DDRec:
  - added ICylinder and CylinderSurface to provide
    access to cylinder radius for the tracking
- teveDisplay: 
  - draw sensitive surfaces in red and helper surfaces in gray
  - protect against missing lcio input file
  - reduced printout from VolumeManager  (changed INFO to DEBUG)

* 2014/04/05-2014/04/29 Frank Gaede
- Implementation of Surface classes for track reconstruction
  - abstract interfaces in DDSurface:  ISurface and IMaterial  
  - implementation in DDRec:  Surface, SurfaceManager, DetectorSurfaces
  - basic functionality exists:
  - meassurement surface vectors u,v, normal and origin
  - check if point is inside the bounds of the corresponding volume
  - currently the material is taken to be the one from the volume 
      -> to do: average material if surface thicknesses extend beyond the
                volume for comound materials
  - added drawing of surfaces and (Sim)TrackerHits and (Sim)CalorimeterHits to teveDisplay
     ( link lcio file to teve_infile.slcio )
  - added some surfaces to ILDExDet: VXD, SIT, TPC
  - added test_surfaces to ILDExSimu
     (fails currently for some hits that are not created on the surface ...)
  - added some assemblies to ILDExDet to better structure the geometry hierarchy   

* 2014/04/28  Markus Frank
- First attempt to understand fully the handling of recursive assemblies
     from the 2014/04/25 was apparently with limited success. Now they should
     work!

* 2014/04/25  Markus Frank
- Moved boost::spirit parsers to DDCore, since these parsers are also used
     in other packages such as DDCond and DDAlign - whenever strings have to be
     converted to objects.
     Consequently, the boost spirit code fragments were removed from DDG4.
- Improved and more correct type checking when assigning handles
- Explicit implementation of the object extension mechanism to be used 
     through inheritance or aggregation rather than having seperate and nearly
     identical implementations for various objects.
- Improved defintition of basic objects describing Conditions and Alignment.
- Improved implementation of DDAlign, the alignment support.
     Not to be used currently - experimental package.
- Initial implementation of DDCond the package supporting the handling of 
     conditions.
     Not to be used currently - experimental package.
- Geant4Converter: I convinced myself, that the bug in handling assemblies
     of assemblies is resolved. To be tested though.

* 2014/02/07  Frank Gaede
- added DDGear, support for interfacing to gear for backward compatibility
  - lives currently in ILDExDet ( should become (optional) part of core dd4hep)
  - users need to GearParameter objects as extensions to the DetElement
       -> see ILDExTPC_geo.cpp, ILDExVXD_geo.cpp, ILDExTPCSIT_geo.cpp as examples
  - program convertToGear creates gear xml file from compact file 
       ( only if  GearParameter objects are avialble as extensions)
  - added test_convert_ild_gear 
- fixed  geometry in ILDExVXD_geo.cpp, ILDExTPCSIT_geo.cpp
     wrt. to position of support ans sensitive ladders

# v00-06   
* 2014/02/04  Frank Gaede
- fixed environment scripts thisdd4hep.sh and this${PackageName}.sh
    to also export library pathes for external libraries (CLHEP, LCIO, gear)

- added some simple tests to ILDExDet, ILDExSimu and noviceN04
  - provide cmake script run_test_package.sh ( configured as run_test_${PackageName} ) 
      to call test binaries after initializing the environment
      (needed for automated/nightly tests)

- updated Readme.txt wrt build procedure and running the tests


* 2014/01/17    Markus Frank
- Prepare implementation of Alignment using Release and Grap features of TGeoVolume
    and TGeoNode. In principle this was done in a backwards compatible way, but 
    I cannot really check 100% the #ifdef's.
- Fix handling of XML collections using XercesC.
    (Bug reported by P.Kostka).
- Fix several compiler warnings issued by Coverity.

* 2013/12/17    Markus Frank
- Whole load of fixes to keep coverity quiet....
- Fix bug in DDG4 field interface component
- Allow the usage of units, positions and lorentzvectors and in DDG4 properties.
    Example using a position property (ROOT::Math::XYZVector):
    Idle> /ddg4/Gun/position (1*mm,1*cm,0.01*m) 
    Geant4UIMessenger: +++ Gun> Setting property value position = (1*mm,1*cm,0.01*m)  
                       native:( 1 , 10 , 10 ).

- Support for std::vector<T>/std::list<T>/std::set<T> properties.

  - Support for include directives of the format
```
        <include ref="file-name"/>
    for the top level <lccdd> tags
       Parent tag    Included root tag  Data content
    -- <lccdd>       <define>           See below.
                     <detectors>
		     <detector>
		     <display>
		     <lccdd>            Nested includes (with DTD validation for Xerces-C)
    -- <define>      <define>           Set of constants
    -- <detectors>   <detector>         Single XML subdetector description
    -- <detectors>   <detectors>        Multiple XML subdetector descriptions
    -- <display>     <display>          Set ov visualization attributes

    DTD validation is only performed using Xerces-C for root tags <lccdd>.
```
- Note: 
    `<lccdd>` include directives are executed BEFORE any other directive!
    Other include directives are executed BEFORE the corresponding named directive!

* 2013/11/14    Markus Frank
- Reformat files in DDCode and DDG4 to remove the <TAB>s from the source files.
    Hopefully the content is now more readable.
- DDCore: Remove empty and named constructors for shapes. Empty constructors
    were simply a dangerous hook to memory leaks, named constructors are 
    deprecated since along time.
- DDG4: add support for messengers to access and modify properties from
    the Geant4 prompt. For the test hit classes and the simple sensitive 
    detector a ROOT I/O plugin was provided.
- DDG4: Split into several libraries:
  - libDDG4.so pure    link library without any plugins
  - libDDG4Legacy.so   'Old' plugins. The old stuff at some point
                               will have to disappear.
  - libDDG4Plugins.so  New framework plugins
  - libDDG4LCIO.so     LCIO output plugin for new framework

* 2013/11/03    Markus Frank
- doc: Add CHEP2013 paper about dd4hep as a start of the documentation 
    section. More to come hopefully.
- DDCore: several small improvements:
  - Segmentations are no longer Ref_t's.
  - Base internal implementing object directly on the segmentations 
      classes from Christian.
  - Rearrangement of some code from Handle.h to Primitives.h
  - Allow to attach extensions to Detector
- DDG4: Fix Frank's simulation problem, which he caused himself
    introducing his famous factories....
- DDG4: First attempt to fix simulation problem with mignetic field.
    Ready for testing.
- DDG4: First commit of a independent simulation aimed for LHCb and LHeC
    + other newcomers. Documentation needs to be written.
    Features:
  - Modular setup of all Geant4 action routines as plugins, including the
      Run-, event-, tracking-, stacking-, stepping- and generator-actions 
      as well as the physics lists with particle and physics constructors.
  - Setup is possible in XML or with C++ either as an AClick in root or
      standalone. Python based starter to come.
  - Missing is a modular description of the G4 UI and VIS manager(s).
  - Documentation is to come. Before documentation is not present
      the usage is discouraged.
    Note:
  - This version of DDG4 uses boost::spirit. It will compile without
      the BOOST include files and the old functionality is preserved, 
      but it will not work.
      To use BOOST add to the cmake statement the following tags:
      cmake <regular tags> \
      -DDD4HEP_USE_BOOST=ON \
      -DBOOST_INCLUDE_DIR=${BOOST_INCLUDE_DIR}  ....
      Where BOOST_INCLUDE_DIR should point to the boost header directory.
      BOOST libraries are not used.

* 2013/10/18    Markus Frank
- Throw exception if the expression evaluator sees a problem.
    The message printed before was often not seen.
- Improve printout on exceptions and plugin abortion
- Remove the typedef RotationZYX -> Rotation and
    import the type RotationZYX from ROOT::Math.

- Add more explicit error messages in case a plugin is not found.
- Add file TGeoUnits.h, which allows to use the "usual SystemOfUnits"
    from CLHEP using TGeo with the namespace tgeo::xxx
```
    Example: tgeo::mm -> 0.1 (Geant3: cm, sec,  GeV, degree)
                 ::mm -> 1.0 (Geant4: mm, nsec, MeV, radian)
    I hope I got all translations right.
    Geant4                                   Geant3
    ----------------------------------------------------------------
    millimeter         mm=1,cm=10            centimeter  mm=0.1,cm=1
    nanosecond         s=1e9                 second      ns=1e-9,s=1
    Mega electron Volt GeV=1e3               GeV         GeV=1
    radian             rad=1                 degree      rad=180/pi

    Unclear to me was if in Geant3 steradian is also 2*2*pi or 2*2*180 degree.
```


* F. Gaede
- changes to build system:
         (see ReadMe.txt for details)

- moved examples to ./example directory   
- they are not built as part of dd4hep anymore

- install thisdd4hep.sh in ./bin
           (modified to have the correct pathes) 

- added -DINSTALL_DOC=on/off option
           to build doxygen documentation (in ./doc/html/index.html)

- create DD4hepConfig.cmake for easy building against dd4hep
           ( see examples CMakeLists.txt)

- fixed doxygen API documentation (C.Rosemann)
          (greatly improved with many graphs)

# v00-04
* F. Gaede
- placement options are now compatible with geant4 
- fixed Geant4SensitiveDetector::getVolumeID()
- modified ILDEx model to not use assemblies (for now !?)
- removed obsolete geant4 example ILDEx
- Fix population procedure of volume manager
- Fix uniqueness of volume identifiers.
- Remove call with lookups by placed volume to the volume manager
- improved ILDEx toy example:	   		
  - fixed creation of cellIDS for simhits
  - creates SimTrackerHits for VXD, SIT and TPC
    - creates SimCalorimeterHits for AHcal barrele and endcap
    - works now wigth ILDExSimu _and_ SLIC if no assemblies are used
    - assemblies work with the dd4hep Geant4Converter and VolumeManager
  - added a prototype example for a ROOT independent 
              plugin mechanism for SensitiveDetectors
  - added example implemetation for Calice test beam
          calorimeters: CaliceTbeam  (Shaojun Lu, DESY)


* 2013/21/06    Markus Frank
- Since the placement model for combined translations and rotations
      caused more confusion than good, it was agreed to move to a more
      Geant4 like placement model using Vectors, Rotations and Transformations
      from ROOT::Math. To place a physical volume only one of these
      is allowed as an argument: either a rotation or a translation
      for simple placements. Combinations may be constructed with Transform3D
      objects allowing more complicated placements.
      The same mechanism was applied for the operations to construct
      boolean solids.
- The CLICSid Examples were updated according to the changes necessary
      from 1)
- The Tesla drivers from the ILDExDet example were removed. They are
      not compliant to 1).
- The G4 package allows now to translate TGeo geometries to Geant4.
      Visual inspection has shown an agreement between the two geometries.
- The TGeo to Detector/GDML conversion is still buggy. Hence, simulations
      using slic as an engine do not yet work. This is being looked at.

   IMPORTANT NOTICE:
   The changes described in above may affect existing detector constructors.
   Unless all problems are solved you should be careful to move to the svn
   head. In any case save your checkout or use the tag v00-03.

 

# v00-03
- broken geometry (for some rotations/translations)
- 'backup release' before placement options 
   will be reduced

# v00-02
* 2013/02/06    Markus Frank
- Simplyfy inheritance for common objects from TNamed.
     Use direct inheritance of Object from TNamed rather than hidden 
     using the Value<a,b> construct.
- Added physical volume manager to simplyfy the detector element 
     and sensitive detector lookup from a given physical volume.
     This implies: If the volume manager is instantiated, the readout specifiers
     MUST be correct. This is in most xml files NOT the case.
     The "system" field holding the sibdetector-id is MANDATORY!
     Otherwise you will receive messages like this:

     Exception:SITCollection: This ID descriptor has no field with the name:CellID0
               while programming VolumeManager. Are your volIDs correct?

- To check the volume identification, add argument -volmgr to geoConverter,
     geoDisplay, etc.
- To trace possible memory leaks:
     export DD4HEP_TRACE=Yes
     then run you converter etc. At the end a table is displayed with a "leakage"
     column, showing how many objects were not deleted.
```
     +----------------------------------------------------------------+
     |   I n s t a n c e   c o u n t e r s   b y    T Y P E I N F O   |
     +----------+---------+-------------------------------------------+
     |   Total  | Leaking |      Type identifier                      |
     +----------+---------+-------------------------------------------+
     |        13|        0|dd4hep::DetElement::Object
     |         3|        0|dd4hep::SensitiveDetector::Object
     |         3|        0|dd4hep::Readout::Object
     |         1|        0|dd4hep::OverlayedField::Object
     |         1|        0|dd4hep::CartesianField::Object
     ....
     Ideally the second column only has "0"s. Instances of 1 may be OK (singletons).
```
- Prenotice:
     As soon as ROOT v 6.00 is out, we will have to use it!
     Andrei kindly agreed to implement a few changes to TGeo, which will make 
     life much easier and the implementation cleaner and less cumbersome.


# v00-01
* 2013/20/03    Markus Frank
- Finished the compact->description converter
     Extract description information
```
      $ > geoConverter -compact2description -input file:<compact-input-xml-file> -output <detector>.description
      $ > <SimDist>/scripts/slic.sh -o output.slcio -g SiD.description -m <geant4-macro>.mac -r 100 
```

- Finished the compact->gdml converter
  Full GDML cycle can be tested (deplace <detector> with some meaningful identifier):
  - Extract gdml information
      `$ > geoConverter -compact2gdml -input file:<compact-input-xml-file> -output <detector>.gdml`
  - Extract visualisation hints to csv file
      `$ > geoConverter -compact2vis -input file:<compact-input-xml-file> -output <detector>.vis.csv -ascii`
  - Load GDML into ROOT:
      `$ > root.exe ../doc/gdml_root.C+\(\"<detector>\"\)`
      The macro expects *at least* the <detector>.gdml file. If no visualisation
      information is found, the resulting graphics however is not very nice!
 

* 2013/22/02    Markus Frank
- Today a decision was taken to remove all _X() and _A() macros 
  accessing static unicode strings. A common macro will be used to
  address both XML elements and XML attributes using the macro _U(...).
  The original usage only created confusion.
  All _X and _A macros were replaced by _U.

- Improve the executables running the plugin mechanism in UtitlityApps.
  They now complain if the plugin was not found.


* 2013/21/02    Markus Frank
- Require strict checks for the existence of xml attributes.
  e.g. default=false for Element::attr<bool>() is no longer an option.
  if the attribute is not present in the element, an exception
  is thrown.

- Slightly change the factory method for creating detector elements.
  Use a more generic pattern do support also more generic XML 
  processing.

* 2013/20/02    Markus Frank
- Install rootmap mechanism for the usage of plugins.
  It is no longer necessary to have separate programs
  for the various detector models (ILD/SiD).
  One generic display program servest them all.
  ==> Creation of package DDExamples/UtilityApps
  example: $> bin/displayGeo -compact <compact-xml-file>

- This move has another consequence:
  All libraries are build into a common install area:
  the <build directory>/lib.
  All executable binaries are build into a common install area:
  the <build directory>/bin.

- The LD_LIBRARY_PATH and PATH variables as defined in 
  'thisdd4hep.(c)sh' do include these directories

* 2013/20/02    Markus Frank
- dd4hep release notes. Better start them late than never.
  If you perform significant changes to the dd4hep core,
  plase leave a small notice here.