ReleaseNotes.md

# v01-23

* 2022-09-28 Wouter Deconinck ([PR#982](https://github.com/aidasoft/dd4hep/pull/982))
  - ddsim: set eta_min, eta_max correctly for `ddsim --gun.distribution eta`

* 2022-09-23 Markus Frank ([PR#980](https://github.com/aidasoft/dd4hep/pull/980))
  Remove using declarations in root-cling dictionary files to avoid interpreter clashes with the global namespace
  
  Affected files:
  -   DDCore/src/GeoDictionary.h
  -   DDCore/src/PropertyDictionary.h
  -   DDCore/src/RootDictionary.h
  -   DDCore/src/SegmentationDictionary.h
  -   DDEve/include/DDEve/Dictionary.h
  -   DDG4/include/DDG4/DDG4Dict.h

* 2022-09-23 Marco Clemencic ([PR#979](https://github.com/aidasoft/dd4hep/pull/979))
  - Use explicit namespaces in DDCond dictionary

* 2022-09-19 Wouter Deconinck ([PR#976](https://github.com/aidasoft/dd4hep/pull/976))
  - `geoConverter -compact2tgeo` to write TGeo geometry to ROOT file

* 2022-09-19 Christopher Dilks ([PR#974](https://github.com/aidasoft/dd4hep/pull/974))
  - add example RICH detector, demonstrating and testing `Geant4OpticalTrackerAction`

* 2022-09-16 Wouter Deconinck ([PR#975](https://github.com/aidasoft/dd4hep/pull/975))
  - materialBudget: enable use with asymmetric detectors: adding thetaMin/thetaMax/etaMin to the steering file

* 2022-09-15 Wouter Deconinck ([PR#967](https://github.com/aidasoft/dd4hep/pull/967))
  - Geant4OpticalTrackerAction which stops-and-kills optical photons for e.g. SiPM sensor planes

* 2022-09-12 Christopher Dilks ([PR#973](https://github.com/aidasoft/dd4hep/pull/973))
  - fix typo in `examples/README.md`: `cmake` option `DD4HEP_BUILD_EXAMPLES` should be `DD4HEP_EXAMPLES`

* 2022-09-07 Dmitry Kalinkin ([PR#972](https://github.com/aidasoft/dd4hep/pull/972))
  - Refactor thisdd4hep.sh to use local variables where possible to prevent user environment corruption.

* 2022-09-01 Andre Sailer ([PR#969](https://github.com/aidasoft/dd4hep/pull/969))
  - DDSim: ddsim now prints out if the defaultFilter or if no filter is used for a sensitive detector

* 2022-09-01 Wouter Deconinck ([PR#968](https://github.com/aidasoft/dd4hep/pull/968))
  - ddsin: Add `--runType qt` support for enabling the graphical Qt interface for geant4
  - ddsim: change shell type to tcsh: enabling tab completion when Geant4 offers it

* 2022-08-26 Andre Sailer ([PR#962](https://github.com/aidasoft/dd4hep/pull/962))
  - DDCore: DetectorInfo: make INFO attributes optional, fixes #960

* 2022-08-25 Andre Sailer ([PR#963](https://github.com/aidasoft/dd4hep/pull/963))
  - ChannelingCrystalMaterial: fix crystal_orientation to be constPropertyRef

* 2022-08-25 Andre Sailer ([PR#961](https://github.com/aidasoft/dd4hep/pull/961))
  - DDSim: fix example for adding user physics list extension

# v01-22

* 2022-08-16 Andre Sailer ([PR#957](https://github.com/aidasoft/dd4hep/pull/957))
  - CI: add check for header guards

* 2022-08-15 Andre Sailer ([PR#956](https://github.com/aidasoft/dd4hep/pull/956))
  - CI: Add test with Geant4Units enabled

* 2022-08-15 Andre Sailer ([PR#946](https://github.com/aidasoft/dd4hep/pull/946))
  - CI changes, for discussion

* 2022-08-11 Markus Frank ([PR#954](https://github.com/aidasoft/dd4hep/pull/954))
  Before starting to parse XML files, programatically set the locale to "C" if any of the three
  - LC_NUMERIC,
  - LC_TIME,
  - LC_CTYPE
  Is not set to "C".
  
  Addresses issue https://github.com/AIDASoft/DD4hep/issues/913.

* 2022-08-11 Andre Sailer ([PR#953](https://github.com/aidasoft/dd4hep/pull/953))
  - DDSim: find the python executable used during build and set that for the hashbang, e.g. python3.9 instead of python. Fixes #952

* 2022-08-10 Markus Frank ([PR#951](https://github.com/aidasoft/dd4hep/pull/951))
  - Allow to set MeanExcEnergy, MeanEnergyPerIonPair and BirksConstant in G4Materials ionisation parameters.
    Specify values in the compact description of the materials:
  ```
      <material name="Ice">
        <D type="density" value="1.0" unit="g/cm3"/>
        <composite n="2" ref="H"/>
        <composite n="1" ref="O"/>
        <constant name="BirksConstant"        value="123.456*mm/MeV"/>
        <constant name="MeanExcitationEnergy" value="79.7*eV"/>
        <constant name="MeanEnergyPerIonPair" value="50*eV"/>
      </material>
  ```
  Units will be converted to Geant4 units in the converter.
  See issue https://github.com/AIDASoft/DD4hep/issues/890 for details.
  
  If in DDG4 the the material debugging is enabled:
  ```
    # Configure G4 geometry setup
    seq, act = geant4.addDetectorConstruction("Geant4DetectorGeometryConstruction/ConstructGeo")
    act.DebugMaterials = True
  ```
  this gives the following output:
  ```
  Ice                    ++ Created G4 material  Material:      Ice    density:  1.000 g/cm3   RadL:  36.083 cm   Nucl.Int.Length:  75.375 cm 
                        Imean:  79.700 eV   temperature: 293.15 K  pressure:   1.00 atm
  
     --->  Element: H (H)   Z =  1.0   N =     1   A =  1.008 g/mole
           --->  Isotope:    H1   Z =  1   N =   1   A =   1.01 g/mole   abundance: 99.989 %
           --->  Isotope:    H2   Z =  1   N =   2   A =   2.01 g/mole   abundance:  0.011 %
            ElmMassFraction:  11.19 %  ElmAbundance  66.67 % 
  
     --->  Element: O (O)   Z =  8.0   N =    16   A = 15.999 g/mole
           --->  Isotope:   O16   Z =  8   N =  16   A =  15.99 g/mole   abundance: 99.757 %
           --->  Isotope:   O17   Z =  8   N =  17   A =  17.00 g/mole   abundance:  0.038 %
           --->  Isotope:   O18   Z =  8   N =  18   A =  18.00 g/mole   abundance:  0.205 %
            ElmMassFraction:  88.81 %  ElmAbundance  33.33 % 
            log(MEE): -9.437  Birk's constant: 123.5 [mm/MeV]  Mean Energy Per Ion Pair: 50 [eV]
  ```

* 2022-08-10 Markus Frank ([PR#950](https://github.com/aidasoft/dd4hep/pull/950))
  On request from out LHC colleagues DD4hep supports channeling physics in Geant4.
  To support channeling physics in Geant4 it is necessary to enable the transparent 
  creation of G4ExtendedMaterial and G4LogicalCrystalVolume instances.
  This can be done in DD4hep with the supply of material and volume properties in DD4hep.
  
  Material properties can be supplied in the compact description like here:
  ```
      <material name="Ice">
        <D type="density" value="1.0" unit="g/cm3"/>
        <composite n="2" ref="H"/>
        <composite n="1" ref="O"/>
        <constant name="Geant4-plugin:material"            option="ChannelingCrystalMaterial"/>
        <constant name="Geant4-ignore:crystal_data"        option="${DD4hepExamplesINSTALL}/examples/DDG4/data/Si220pl/Si220pl"/>
        <constant name="Geant4-ignore:crystal_orientation" option="(1,0,0)"/>
      </material>
  ```
  The property starting with the tag `Geant4-plugin` is used to determine the proper plugin
  preparing the G4ExtendedMaterial instance.
  All properties with tags `Geant4-ignore` are not passed as material properties to Geant4.
  Properties starting with this tag can be used by users to configure the G4ExtendedMaterial instance.
  
  Volumes can as well have properties as this C++ example shows:
  ```
    Volume vol = Volume("Volume", solid, material);
    xml_elt_t ec = ...;
    vol.addProperty(ec.attr<std::string>(_U(name)), ec.attr<std::string>(_U(value)));
  ```
  with values supplied by XML:
  ```
    <property name="Geant4-plugin" value="ChannelingCrystalVolume"/>
  ```
  For more details see the example `<DD4hep>/examples/DDG4/compact/Channeling.xml`.
  Again the property `Geant4-plugin` is used to call a plugin to create sub-classes
  of G4LogicalVolume like G4LogicalCrystalVolume. 
  
  An example was prepared in `<DD4hep>/examples/DDG4` containing:
  - a compact description: `compact/Channeling.xml`
  - an example factory for the G4ExtendedMaterial: `src/ChannelingCrystalMaterial.cpp`
  - an example factory for the G4LogicalCrystalVolume: `src/ChannelingCrystalVolume.cpp`
  - A script invoking Geant4 to test this setup: `scripts/Channeling.py`

* 2022-08-09 Dmitry Kalinkin ([PR#949](https://github.com/aidasoft/dd4hep/pull/949))
  - DDSim: restore the fixed momentum behaviour of `--gun.energy`, independent of the isotrop setting for the particle gun. If gun.energy is set, the momentum will have this value. If it is not set, momentumMin and momentumMax will be used to pick a value.

* 2022-08-05 Andre Sailer ([PR#942](https://github.com/aidasoft/dd4hep/pull/942))
  - DDSim: add option to set userInputPlugin for simulation by adding a plugin for themselves, and this to the ddsim steering file (for #940)
     ```python
        def exampleUserPlugin(dd4hepSimulation):
          '''Example code for user created plugin.
  
          :param DD4hepSimulation dd4hepSimulation: The DD4hepSimulation instance, so all parameters can be accessed
          :return: GeneratorAction
          '''
          from DDG4 import GeneratorAction, Kernel
          # Geant4InputAction is the type of plugin, Cry1 just an identifier
          gen = GeneratorAction(Kernel(), 'Geant4InputAction/Cry1' , True)
          # CRYEventReader is the actual plugin, steeringFile its constructor parameter
          gen.Input = 'CRYEventReader|' + 'steeringFile'
          # we can give a dictionary of Parameters that has to be interpreted by the setParameters function of the plugin
          gen.Parameters = {'DataFilePath': '/path/to/files/data'}
          gen.enableUI()
          return gen
  
        SIM.inputConfig.userInputPlugin = exampleUserPlugin
     ```

* 2022-08-04 Andrea Ciarma ([PR#944](https://github.com/aidasoft/dd4hep/pull/944))
  * Mask_o1: Added the possibility to have sensitive elements of type Mask_o1_v01_geo by adding a `sensitive="sensitiveType"` attribute

* 2022-08-02 Juraj Smiesko ([PR#941](https://github.com/aidasoft/dd4hep/pull/941))
  * checkOverlaps.py: Adding possibility to provide multiple compact files
  * checkOverlaps.py: replace optparse by argparse for up-to-date python

* 2022-08-01 Markus Frank ([PR#939](https://github.com/aidasoft/dd4hep/pull/939))
  - Follow up of https://github.com/AIDASoft/DD4hep/pull/938. 
    Improves the DetectorCheck plugin.
  - Add example with an "ill" detector description that triggers the DetectorCheck plugin
    to complain and to eject pathes to problematic detector elements ect.

* 2022-07-29 Markus Frank ([PR#938](https://github.com/aidasoft/dd4hep/pull/938))
  - Fix type in DDCore/src/DD4hepRootPersistency.cpp
  - Add operator== and operator != to handles of DetElement, SensitiveDetector
    Volume and PlacedVolume. Check pointer values for equality.
  - Add plugin DD4hep_DetectorCheck. Improves and replaces DD4hep_VolumeMgrTest.
    o Test checks the strutural tree of a given top element
    o Test checks the geometry tree of a given top element
    o If physical volume ids are properly placed these can also be checked.
  ```
  DD4hep_DetectorCheck -option [-option]                                         
    -help                        Print this help message                         
    -name  <subdetector name>    Name of the subdetector to be checked           
                                 "ALL" or "all": loop over known subdetectors
                                 "world" start from the mother of all...       
    -structure                   Check structural tree consistency               
    -geometry                    Check geometry tree consistency                 
    -sensitve                    Check consistency between detector and volume   
                                 settings of sensitive detectors.                
    -volmgr                      Check volume manager entries against volIDs of  
                                 sensitive volume placements.                  
  
                                 NOTE: Option requires proper PhysVolID setup    
                                 of the sensitive volume placements !
  ```

* 2022-07-27 Juraj Smiesko ([PR#937](https://github.com/aidasoft/dd4hep/pull/937))
  - Improving error message when setting detector type flags

* 2022-07-27 Andre Sailer ([PR#935](https://github.com/aidasoft/dd4hep/pull/935))
  - ddsim: Fix setting of zeroTimePDGs, previously this value was not forwarded from config to the program
  - particle.tbl: change 523 to unstable (fixes #909)
  - Geant4InputHandling: add exception when encountering stable particles with daughters that are marked for simulation (implements feature of #909)
  - Geant4InputHandling: reject particles with GEN_DOC, GEN_BEAM, GEN_OTHER (fixes part of #918)

* 2022-07-26 Markus Frank ([PR#936](https://github.com/aidasoft/dd4hep/pull/936))
  - Recursive calls to apply-plugins overwrote the return code.
  - This MR fixes issue https://github.com/AIDASoft/DD4hep/issues/875
  
  - Support for 1D, 2D and 3D parameterised volumes.
    (Outstanding request by S.Ko)
    1. TGeo does not support parametrized volumes intrinsically.
      On the dd4hep/TGeo side these are implemented by multiple placements 
      according to the user supplied transformation matrices.
      For details see the calls in `dd4hep::Volume::paramVolume<dim>D(...)`
    2. When translated to Geant4, the structures are identified and
      the proper Geant4 parameterisation is created.
    3. An example can be found in:
      - `examples/ClientTests/src/ParamVolume_geo.cpp`
      - to display: `geoDisplay examples/ClientTests/compact/ParamVolume<dim>D.xml`
      - the Geant4 conversion is excercised with the scripts:
        ```
        python examples/ClientTests/scripts/ParamVolume.py \
           -geometry examples/ClientTests/compact/ParamVolume<dim>D.xml \
           -vis -macro examples/ClientTests/compact/ParamVolume.mac ```

# v01-21

* 2022-07-19 Markus Frank ([PR#933](https://github.com/aidasoft/DD4hep/pull/933))
  The fast simulation handling in Geant4 includes the GFlash interface
  as implemented in `<geant40-source>/source/parameterisations/gflash`
  and a fast simulation interface as provided by 
  `<geant40-source>/source/processes/parameterisation`
  
  This MR allows to handle both mechanisms using the same callbacks 
  in the Geant4SensitiveActions using the callback specialization:
  ```
        /// GFLASH/FastSim interface: Method for generating hit(s) using the information of the fast simulation spot object.
        virtual bool processFastSim(const Geant4FastSimSpot* spot, G4TouchableHistory* history)  final;
  ```
  in addition to the regular callback for full simulation:
  ```
        /// G4VSensitiveDetector interface: Method for generating hit(s) using the G4Step object.
        virtual bool process(const G4Step* step,G4TouchableHistory* history)  final;
  ```
  The `Geant4FastSimSpot` is inspired by the `G4GFlashSpot`, but avoids the specialization towards GFlash
  given that the `G4FastHit` and the `G4GFlashEnergySpot` are equivalent.
  Together with the helper class `Geant4FastSimHandler` simple sensitive detector callbacks
  can be implemented like:
  ```
      /// GFlash/FastSim interface: Method for generating hit(s) using the information of Geant4FastSimSpot object.
      template <> bool
      Geant4SensitiveAction<Geant4Tracker>::processFastSim(const Geant4FastSimSpot* spot,
  							 G4TouchableHistory* /* hist */)
      {
        typedef Geant4Tracker::Hit Hit;
        Geant4FastSimHandler h(spot);
        Hit* hit = new Hit(h.trkID(), h.trkPdgID(), h.deposit(), h.track->GetGlobalTime());
        hit->cellID        = cellID(h.touchable(), h.avgPositionG4());
        hit->energyDeposit = h.deposit();
        hit->position      = h.avgPosition();
        hit->momentum      = h.momentum();
        hit->length        = 0e0;
        collection(m_collectionID)->add(hit);
        return true;
      }
  ```
  Callbacks with this signature are called both for GFlash and the G4 fast simulation.
  
  To simplify the user defined construction of fast simulation shower models
  the helper class `Geant4FastSimShowerModel` is implemented as a `Geant4Action`
  and hence allows to have options to be set by the user (including python).
  
  As an illustration two fast simulation shower models were implemented in
  `<dd4hep>/DDG4/plugins/Geant4P1ShowerModel.cpp` which were directly deduced
  from the Geant4 example `<geant4-source>/examples/extended/parameterisations/Par01`.
  Please see the source files for details.
  
  To execute GFlash or fast simulation to simple python examples are provided
  using simple silicon blocks as sensitive volumes:
  - GFlash `<dd4hep-dir>/examples/ClientTests/scripts/SiliconBlockGFlash.py`
  - Fast simulation `<dd4hep-dir>/examples/ClientTests/scripts/SiliconBlockFastSim.py`
  
  To enable either the following actions are required:
  1. Enable fast simulation for certain particles in the physics list:
  ```  # Build the physics list:
    phys = geant4.setupPhysics('FTFP_BERT')
    ph = DDG4.PhysicsList(kernel, str('Geant4FastPhysics/FastPhysicsList'))
    ph.EnabledParticles = ['e+', 'e-']
    ph.enableUI()
    phys.adopt(ph)
  ```
  This step is identical for GFlash and fast simulation physics.
  2. Enable the shower mode:
  ```  model = DDG4.DetectorConstruction(kernel, str('Geant4Par01EMShowerModel/ShowerModel'))
    # Mandatory model parameters
    model.RegionName = 'SiRegion'
    model.Material = 'Silicon'
    model.ApplicableParticles = ['e+', 'e-']
    model.Etrigger = {'e+': 0.1 * GeV, 'e-': 0.1 * GeV}
    model.Enable = True
    model.enableUI()
  ```
  Here the options must be set according to the parameters required by the shower models.
  
  The G4 fast simulation interface is only functional for Geant4 version >= 10.07.
  For lower versions of Geant4 missing classes are stubbed to allow the compilation.

* 2022-07-18 Paul Gessinger ([PR#931](https://github.com/aidasoft/DD4hep/pull/931))
  - Update `VariantParameters`: `value_or` is const (returns by value anyway), add non-const `get` method

* 2022-07-15 Markus Frank ([PR#930](https://github.com/aidasoft/DD4hep/pull/930))
  - Fix some handler
  - Add 2 examples to test the functionality

* 2022-07-14 Markus Frank ([PR#929](https://github.com/aidasoft/DD4hep/pull/929))
  - First attempt to implement GFlash parametrization for DDG4
  - Example is in examples/ClientTests/scripts/SiliconBlockGFlash.py
    Relevant code changes are for the detector construction:
    ```
    seq, act = geant4.addDetectorConstruction('Geant4DetectorGeometryConstruction/ConstructGeo')
    ....
    # Enable GFlash shower model
    model = DDG4.DetectorConstruction(kernel, str('Geant4GFlashShowerModel/ShowerModel'))
    model.Parametrization = 'GFlashHomoShowerParameterisation'
    # Mandatory model parameters
    model.RegionName = 'SiRegion'
    model.Material = 'Silicon'
    model.Enable = True
    # Energy boundaries are optional
    model.Emin  = {'e+': 0.1*GeV, 'e-': 0.1*GeV }  # Units in GeV
    model.Ekill = {'e+': 0.1*MeV, 'e-': 0.1*MeV }
    model.enableUI()
    seq.adopt(model)
    ```
    and the physics list.
    ```
    # Now build the physics list:
    phys = geant4.setupPhysics('FTFP_BERT')
    ph = DDG4.PhysicsList(kernel, str('Geant4FastPhysics/FastPhysicsList'))
    ph.EnabledParticles = ['e+', 'e-']
    ph.BeVerbose = True
    ph.enableUI()
    phys.adopt(ph)
    ```
  The setup of the regions is crucial for GFlash to work, because it applies to regions.
  For concrete detector constructors the proper regional setting are mandatory, but do not affect
  this implementation.

* 2022-07-12 Andre Sailer ([PR#928](https://github.com/aidasoft/DD4hep/pull/928))
  - CI: Due to incompatibilities we can no longer test macOS on github

* 2022-07-12 Markus Frank ([PR#927](https://github.com/aidasoft/DD4hep/pull/927))
  Easy possibility to store condition payloads as std::any.
  - Use of specialized handle class `dd4hep::ConditionAny` to support the functionality.
    The payload is automatically bound to an object of type std::any.
    Example code of constructor and how to access data:
     ```
    /// Emplacement construction
    std::vector<int> value;
    ... // fill data
    ConditionAny c2("name", "type", std::move(value));
  
    /// Construct conditions object with empty std::any	 
    ConditionAny c2("name", "type");
    /// Assign data (empty vector<int>) to the payload:
    c2.get() = vector<int>();
  
    /// Access data:
    vector<int>& data = c2.as<vector<int> >();
       ```
     as a corollary to this approach these conditions can only be stored and retrieved from ROOT storage 
     if the requirement for ROOT are satisfied. Otherwise no other restrictions are imposed. 
     The corresponding grammar instance is part of the library.
  
  - Add example to illustrate the functionality in example/conditions:
     o   examples/Conditions/src/ConditionAnyExampleObjects.cpp
     o   examples/Conditions/src/ConditionAnyExampleObjects.h
     o   plugin: examples/Conditions/src/ConditionAnyExample_populate.cpp
         Invocation:
  ```
     $> geoPluginRun  -destroy -plugin DD4hep_ConditionAnyExample_populate \
          -input ../../DD4hep/examples/AlignDet/compact/Telescope.xml -iovs 1
     ```
  
  - Plugin example to test basic functionality and verify proper assignment works
     o   examples/Conditions/src/Conditions_any_basic.cpp
         Invocation:
  ```
  $> geoPluginRun -destroy -volmgr -plugin DD4hep_Conditions_any_basic
  
  ```
  - Add 2 tests illustrating this functionality.

* 2022-07-09 Markus Frank ([PR#925](https://github.com/aidasoft/DD4hep/pull/925))
  Easy possibility to store condition payloads as std::any.
  - Use of specialized handle class `dd4hep::ConditionAny` to support the functionality.
    The payload is automatically bound to an object of type std::any.
    Example code of constructor and how to access data:
     ```
    /// Emplacement construction
    std::vector<int> value;
    ... // fill data
    ConditionAny c2("name", "type", std::move(value));
  
    /// Construct conditions object with empty std::any	 
    ConditionAny c2("name", "type");
    /// Assign data (empty vector<int>) to the payload:
    c2.get() = vector<int>();
  
    /// Access data:
    vector<int>& data = c2.as<vector<int> >();
       ```
     as a corollary to this approach these conditions can only be stored and retrieved from ROOT storage 
     if the requirement for ROOT are satisfied. Otherwise no other restrictions are imposed. 
     The corresponding grammar instance is part of the library.
  
  - Add example to illustrate the functionality in example/conditions:
     o   examples/Conditions/src/ConditionAnyExampleObjects.cpp
     o   examples/Conditions/src/ConditionAnyExampleObjects.h
     o   plugin: examples/Conditions/src/ConditionAnyExample_populate.cpp
         Invocation:
  ```
     $> geoPluginRun  -destroy -plugin DD4hep_ConditionAnyExample_populate \
          -input ../../DD4hep/examples/AlignDet/compact/Telescope.xml -iovs 1
     ```
  
  - Plugin example to test basic functionality and verify proper assignment works
     o   examples/Conditions/src/Conditions_any_basic.cpp
         Invocation:
  ```
  $> geoPluginRun -destroy -volmgr -plugin DD4hep_Conditions_any_basic
  
  ```

* 2022-07-07 Andre Sailer ([PR#922](https://github.com/aidasoft/DD4hep/pull/922))
  - LCIOOutput: Fix exception when trying to use a readout for different sub-detectors
  - EDM4hepOutput: Fix memory leak when re-using readouts for different sub-detectors

* 2022-06-16 Markus Frank ([PR#917](https://github.com/aidasoft/DD4hep/pull/917))
  -- Improve error reporting if derived condition dependencies cannot be resolved 
  -- Add illustrating example

* 2022-06-14 Paul Gessinger ([PR#911](https://github.com/aidasoft/DD4hep/pull/911))
  - Add `VariantParameters` extension + plugin to assign parameters to it by name.

* 2022-06-08 Andre Sailer ([PR#914](https://github.com/aidasoft/DD4hep/pull/914))
  - DDSim: add possibility to use individual compact files, e.g.:
      ddsim --compactFile $DD4hep/examples/CLICSiD/compact/SiD_multiple_inputs.xml $DD4hep/examples/CLICSiD/compact/SiD_detectors_1.xml  $DD4hep/examples/CLICSiD/compact/SiD_detectors_2.xml $DD4hep/examples/CLICSiD/compact/SiD_close.xml --runType shell

* 2022-05-18 Andre Sailer ([PR#912](https://github.com/aidasoft/DD4hep/pull/912))
  - Detector: some corrections to the function docstrings

* 2022-05-09 Marco Clemencic ([PR#910](https://github.com/aidasoft/DD4hep/pull/910))
  - Plugin Service: check that the `LD_LIBRARY_PATH` (or `PATH` or `DYLD_LIBRAY_PATH`) are actually set before trying to use them (to avoid a crash)

* 2022-04-29 Andre Sailer ([PR#908](https://github.com/aidasoft/DD4hep/pull/908))
  -  CMake: add a message about how to avoid errors when manuals cannot be build, fixes #907

* 2022-04-28 Juraj Smiesko ([PR#906](https://github.com/aidasoft/DD4hep/pull/906))
  - bootstrap script runs all tests

* 2022-04-28 Andre Sailer ([PR#905](https://github.com/aidasoft/DD4hep/pull/905))
  - SegmentationInterna: fix shadow warning for `s`
  - DDEve: fix shadow warnings for menuBar (bar), s

# v01-20-02

* 2022-04-04 Sanghyun Ko ([PR#902](https://github.com/aidasoft/dd4hep/pull/902))
  - Fix a bug that cannot set G4 const property, following up #884

* 2022-03-30 Valentin Volkl ([PR#899](https://github.com/aidasoft/dd4hep/pull/899))
  - cmake: DD4hepConfig: Drop unnecessary call to DD4HEP_SETUP_BOOST_TARGETS

* 2022-03-30 Markus Frank ([PR#898](https://github.com/aidasoft/dd4hep/pull/898))
  - Reduce coverity warnings

* 2022-03-21 Markus Frank ([PR#897](https://github.com/aidasoft/dd4hep/pull/897))
  See for the example
  -- /examples/ClientTests/src/MaterialTester_geo.cpp
  -- /examples/OpticalSurfaces/compact/ReadMaterialProperties.xml
  -- /examples/OpticalSurfaces/scripts/ReadMaterialProperties.py
  
  The python file is only there to show that the G4 simulation does not get screwed.....
  Otherwise: to define properties, which do not participate in Geant4:
  ```
      <material name="Water">
        <D type="density" value="1.0" unit="g/cm3"/>
        <composite n="2" ref="H"/>
        <composite n="1" ref="O"/>
        <!-- Properties used by Geant4    -->
        <property name="RINDEX"        ref="RINDEX__0x123aff00"/>
        <property name="ABSLENGTH"     ref="ABSLENGTH__0x123aff00"/>
        <property name="FASTCOMPONENT" ref="FASTCOMPONENT__0x123aff00"/>
        <property name="SLOWCOMPONENT" ref="SLOWCOMPONENT__0x123aff00"/>
        <!-- Properties ignored by Geant4 -->
        <property name="Property_of_mine" ref="Water__0x123aff00"/>
        <constant name="BirksConstant"    ref="Birk__Water|Geant4-ignore"/>
        <!-- Constants  ignored by Geant4 -->
        <constant name="Constant_of_mine" ref="Water__Mine|Geant4-ignore"/>
      </material>
  ```
  where:
  ```
    <properties>
      <constant name="Birk__Water|Geant4-ignore" value="12.345678"/>
      <constant name="Water__Mine|Geant4-ignore" value="87.654321"/>
    </properties>
  ```
  and
  ```
      <matrix name= "Water__0x123aff00" option="Geant4-ignore" coldim="1" values="  
                2.034*eV 
                2.068*eV 
                2.103*eV 
                2.139*eV 
                2.177*eV 
                2.216*eV 
      "/>
    </properties>
  ```
  For non-const properties you have to set the option to "Geant4-ignore",
  otherwise you append the string to the name. The "ref" string in the material
  and the property must match.
  In the program you can then access the propertiers by name like this:
  ```
  Material material(...)
  double v = material->GetConstProperty("BirksConstant");
  TGDMLMatrix* m = material->GetProperty("Property_of_mine");
  ```
  like any other property. See for details:
  /examples/ClientTests/src/MaterialTester_geo.cpp lines 78-108

* 2022-03-21 Wouter Deconinck ([PR#896](https://github.com/aidasoft/dd4hep/pull/896))
  - edm4hep: don't add particle as parent to its daughters, and vice versa

* 2022-03-15 Paul Gessinger ([PR#895](https://github.com/aidasoft/dd4hep/pull/895))
  - Allow relaxing the python version requirements at CMake level via option `DD4HEP_RELAX_PYVER`.

# v01-20-01

* 2022-03-08 Markus FRANK ([PR#894](https://github.com/AIDASoft/DD4hep/pull/894))
  - The refactoring of namespaces (some years ago) left some factory name discrepancies in DDEve.
  This PR fixes them and re-enables the various views and projections.
  See issue https://github.com/AIDASoft/DD4hep/issues/893.
  - There are still some issues when loading a new file, which are not yet entirely understood.
  The suspicion is that the displayed 2D histograms somehow "reside" in the opened file and disappear
  when the file is closed. This however needs confirmation (and eventually fixing).

* 2022-03-04 Wouter Deconinck ([PR#892](https://github.com/AIDASoft/DD4hep/pull/892))
  - Support `ddsim --gun.momentumMin 1*GeV --momentumMax 10*GeV` (default remains momentumMin = 0.0)

* 2022-02-25 Andre Sailer ([PR#891](https://github.com/AIDASoft/DD4hep/pull/891))
  - DDParsers: do not use deprecated boost headers with boost 1.78
  - DDG4 Particle.tbl: drop some diffr(active) particles causing warnings with Geant4 11.0
  - DetectorIMP: Changing message about Geant4 unit system to INFO, fixes #844
  - Volumes: Changing message about REFLECTION to DEBUG, fixes #844

# v01-20

* 2021-12-21 Markus Frank ([PR#888](https://github.com/aidasoft/DD4hep/pull/888))
  - Changes for Geant4 11.0.0.
    Propagate additional setup properties for optical parameters in Geant4ScintillationPhysics.
    Other required changes were already included when preparing for the Geant4 beta release.
  - Allow for Geant4 builds without GDML.
    Enable conditional build if the Geant4 build does not support GDML

* 2021-12-16 Thomas Madlener ([PR#887](https://github.com/aidasoft/DD4hep/pull/887))
  - Rework the EDM4hep output action. The major reason is the renaming of the default types in AIDASoft/podio#205 and its effects on EDM4hep (key4hep/EDM4hep#132). These changes are:
    - Use `auto` wherever possible to remove any explicit mentioning of EDM4hep types.
    - Switch to range-based for-loops where possible
    - Keep an internal map of the collections to get rid of the `const_cast`s that were used before.
  - EDM4hep output: Make sure that the daughter relations are also set, because that is not done automatically in EDM4hep but is in LCIO.

* 2021-12-02 Wouter Deconinck ([PR#886](https://github.com/aidasoft/DD4hep/pull/886))
  - Add diquarks to default DDG4 rejectPDGs list

* 2021-11-26 Markus Frank ([PR#885](https://github.com/aidasoft/DD4hep/pull/885))
  - Remove another occurrency of a call to G4::GetPropertyIndex() with 2nd argument.
  - This PR is an addendum to the already closed request https://github.com/AIDASoft/DD4hep/pull/884

* 2021-11-22 Markus Frank ([PR#884](https://github.com/aidasoft/DD4hep/pull/884))
  - Issue https://github.com/AIDASoft/DD4hep/issues/881
    Next attempt for resolution. Avoid explicit use of the second argument in 
  ```
    G4int GetConstPropertyIndex(const G4String& key,
                                G4bool warning = false) const;
    // Get the constant property index from the key-name
  
    G4int GetPropertyIndex(const G4String& key, G4bool warning = false) const;
    // Get the property index by the key-name.
    ```
    Should satisfy existing and future snapshots of Geant4.

# v01-19

* 2021-11-12 Markus Frank ([PR#882](https://github.com/aidasoft/DD4hep/pull/882))
  - See issue in github: https://github.com/AIDASoft/DD4hep/issues/881
  - Material properties have changed in Geant4 between version 10 and 11.
  - This fix should fix the compilation problems and take new properties in Geant4.11 into account.

* 2021-11-12 MarkusFrankATcernch ([PR#876](https://github.com/aidasoft/DD4hep/pull/876))
  - Fix cmake issue when using cmake 3.16.3 (or any of the other versions of cmake that require special python version handling presumably) in a dependent package.

* 2021-11-10 Ben Couturier ([PR#880](https://github.com/aidasoft/DD4hep/pull/880))
  - Added the default move constructor and default move assignment operator to dd4hep::detail::ConditionObject and dd4hep::NamedObject

* 2021-11-03 Markus Frank ([PR#877](https://github.com/aidasoft/DD4hep/pull/877))
  - To not compromize client code with an enforced termination handler, the DD4hep termination handler
  moved to DDG4, where it actually is needed. In DDG4 the termination handler is activated when the main
  Geant4Kernel instance is created.
  Reasoning: Please see issue https://github.com/AIDASoft/DD4hep/issues/874 .
  - Throw an exception if clients ask a DetElement handle for a child by name if such a child is not present or the handle is invalid. This is the new default now. The old behaviour is kept with a second accessor for children by name, with an explicit statement that an exception is unwanted such as: child = DetElement::child("name", false)
  Please see issue: https://github.com/AIDASoft/DD4hep/issues/878.

* 2021-10-13 Markus Frank ([PR#873](https://github.com/aidasoft/DD4hep/pull/873))
  - Remove internal classes from evaluator. Use STL provided classes 
  - Remove hidden clashes with CLHEP evaluator (move internal class Item to anonymous namespace)

* 2021-09-22 Wouter Deconinck ([PR#872](https://github.com/aidasoft/DD4hep/pull/872))
  - Allow for specifying MomentumMin and MomentumMax in Geant4IsotropeGenerator

* 2021-09-15 Markus Frank ([PR#871](https://github.com/aidasoft/DD4hep/pull/871))
  - Finalize CAD stuff.
  - Fix issue https://github.com/AIDASoft/DD4hep/issues/870

# v01-18

* 2021-09-07 Wouter Deconinck ([PR#869](https://github.com/aidasoft/DD4hep/pull/869))
  - Use G4OpticalParameters in geant4.10.7 and newer

* 2021-09-06 Andre Sailer ([PR#863](https://github.com/aidasoft/DD4hep/pull/863))
  - DDSim: add possibility for users to inject configurations for their own output plugins. See example in OutputConfig section of the steering file

* 2021-08-31 Markus Frank ([PR#867](https://github.com/aidasoft/DD4hep/pull/867))
  - Mainly update reference files for CAD shape tests, since the order of the vertices changed when adding facets
    with vertex indices rather than coordinates.

* 2021-08-30 Markus Frank ([PR#866](https://github.com/aidasoft/DD4hep/pull/866))
  - The export of beoolean shapes (union, subtraction, intersection) to was not properly working
    and actually casued segment vialotions. This PR fixes the problem and handles these shapes
    properly using the RootCsg operations for boolean shapes.
  - Examples geometries were provided by Gerri from FCC:  examples/ClientTests/compact/FCCmachine and files thereein.
  - Test example is in DDCAD:   DDCAD_export_FCC_machine and DDCAD_import_FCC_machine
  - This PR addresses the issues: https://github.com/AIDASoft/DD4hep/issues/813 , https://github.com/AIDASoft/DD4hep/issues/858

* 2021-08-25 Markus Frank ([PR#865](https://github.com/aidasoft/DD4hep/pull/865))
  - In cmake tests use the macro ${Python_EXECUTABLE} to invoke the python interpreter rather than
    only `python`.
  - if  `FIND_PACKAGE(Python ${REQUIRE_PYTHON_VERSION} EXACT QUIET COMPONENTS Interpreter)`
    does not resolve the python executable fall back to `python${Python_VERSION_MAJOR}`.

* 2021-08-24 Markus FRANK ([PR#864](https://github.com/aidasoft/DD4hep/pull/864))
  - Support for multiple readouts or (G4VUserParallelWorld equivalent)
    Issue https://github.com/AIDASoft/DD4hep/issues/861
    Example: 
    examples/CLICSiD/compact/SiD_ECAL_Parallel_Readout.xml + 
    examples/CLICSiD/scripts/SiD_ECAL_Parallel_Readout.py
  
    For a given subdetector the sequence of sensitive actions can be enhanced
    having multiple sensitive actions where each one can have its own Readout
    definition. Hence each action can produce its own set of hits depending on the
    readout geometry (segmentation).
    in XML these readout structures must first be defined:
  ```
    <readouts>
      <readout name="EcalBarrelHits">
        <segmentation type="CartesianGridXY" grid_size_x="3.5" grid_size_y="3.5" />
        <id>system:8,barrel:3,module:4,layer:6,slice:5,x:32:-16,y:-16</id>
      </readout>        
  
      <readout name="EcalBarrelHits_0">
        <segmentation type="CartesianGridXY" grid_size_x="1" grid_size_y="1" />
        <id>system:8,barrel:3,module:4,layer:6,slice:5,x:32:-16,y:-16</id>
      </readout>        
   ....
    </readouts>
  
  ```
  and can then be assigned to the sensitive actions in the python setup:
  ```  det = str('EcalBarrel')
    typ = sid.geant4.sensitive_types['calorimeter']
    seq = DDG4.SensitiveSequence(sid.kernel, str('Geant4SensDetActionSequence/') + det)
    seq.enableUI()
    act = DDG4.SensitiveAction(sid.kernel, str(typ + '/EcalBarrelHandler'), det)
    act.enableUI()
    seq.add(act)
    # Add extra parallel readout action with readout EcalBarrelHits_0
    act = DDG4.SensitiveAction(sid.kernel, str(typ + '/EcalBarrelHandler_0'), det)
    act.ReadoutName = 'EcalBarrelHits_0'
    act.enableUI()
    seq.add(act)
    # Add extra parallel readout action with readout EcalBarrelHits_1
    act = DDG4.SensitiveAction(sid.kernel, str(typ + '/EcalBarrelHandler_1'), det)
    act.ReadoutName = 'EcalBarrelHits_1'
  ...
  ```

* 2021-08-10 Wouter Deconinck ([PR#860](https://github.com/aidasoft/DD4hep/pull/860))
  - Optionally import gdml physvol below top level, avoiding world

* 2021-08-03 Valentin Volkl ([PR#855](https://github.com/aidasoft/DD4hep/pull/855))
  - [testing] separate import test for ddg4 and rest of dd4hep

* 2021-07-29 Markus FRANK ([PR#853](https://github.com/aidasoft/DD4hep/pull/853))
  - Implement fix as proposed in issue https://github.com/AIDASoft/DD4hep/issues/850.

* 2021-07-27 Whitney Armstrong ([PR#851](https://github.com/aidasoft/DD4hep/pull/851))
  - Using `ref="OtherVisName"` attribute with the `vis` tag, the visualization attribute is an extension of
  `"OtherVisName"` which is used to initialize the new vis attribute.
   - The new VisAttr inherits all the properties  of the ref and additional arguments override these values.
  
  Example where the only difference is the `alpha` value.
  
  ```
    <vis name="SiVertexBarrelModuleVis"
         alpha="1.0" r="1.0" g="0.75" b="0.76"
         drawingStyle="wireframe"
         showDaughters="false"
         visible="true"/>
  
    <vis name="SiVertexEndcapModuleVis"
         ref="SiVertexBarrelModuleVis"
         alpha="0.5"/>
  ```

* 2021-07-22 Whitney Armstrong ([PR#849](https://github.com/aidasoft/DD4hep/pull/849))
  - Fix G4Sphere construction to use delta theta/phi instead of TGeo's ending angles phi2/theta2.

* 2021-07-21 Placido Fernandez Declara ([PR#847](https://github.com/aidasoft/DD4hep/pull/847))
  - EDM4hepOutput: On collection creation for EDM4hep, save CellIDEncodingString

* 2021-06-24 Thomas Madlener ([PR#843](https://github.com/aidasoft/DD4hep/pull/843))
  - Explicitly enable `C` as language to avoid problems in the build file generation step of cmake (see spack/spack#24232)

# v01-17-00

* 2021-06-02 Andre Sailer ([PR#838](https://github.com/aidasoft/DD4hep/pull/838))
  - Geant4ShapeConverter: ExtrudedSolid: convert all vertices, fix #836, https://github.com/cms-sw/cmssw/issues/33656

* 2021-06-01 Marko Petric ([PR#840](https://github.com/aidasoft/DD4hep/pull/840))
  - Do not propagate CMAKE_BUILD_TYPE in DD4hepConfig.cmake

* 2021-05-27 Markus FRANK ([PR#835](https://github.com/aidasoft/DD4hep/pull/835))
  - On divisions the created solids did not carry the proper tag to identify them.
    This PR fixes this issue when multi-volumes are imported in dd4hep.
    See issue https://github.com/AIDASoft/DD4hep/issues/833

* 2021-05-17 Markus FRANK ([PR#829](https://github.com/aidasoft/DD4hep/pull/829))
  - Add missing Solid instantiation for TGeoCtub

* 2021-05-12 Andre Sailer ([PR#823](https://github.com/aidasoft/DD4hep/pull/823))
  - DDSim: add possibility for users to extend the physics setup with Physics.setupUserFunction

* 2021-05-07 Markus FRANK ([PR#825](https://github.com/aidasoft/DD4hep/pull/825))
  - Fix as reported from CMS

* 2021-05-01 Markus FRANK ([PR#821](https://github.com/aidasoft/DD4hep/pull/821))
  - Fix issue #820

* 2021-04-27 Andre Sailer ([PR#817](https://github.com/aidasoft/DD4hep/pull/817))
  - Move `create_segmentation` to DDCore/include/DD4hep/detail/SegmentationsInterna.h  to allow segmentation creation in other libraries
  - Removed REGISTER_SEGMENTATION macro and DDSegmentation::SegmentationFactory class because they are obsolete. Use DECLARE_SEGMENTATION to create a plugin entry for segmentations.

* 2021-04-24 Markus FRANK ([PR#816](https://github.com/aidasoft/DD4hep/pull/816))
  - Following requests, the support to output Volumes as CAD meshes.
    Depending on the underlying technology material names and visual attributes are supported
  - Improve CAD imports to take into account material names and visual attributes if supported
    by the underlying CAD format.
  - Add two examples showing the import and export technique.

* 2021-04-15 Markus FRANK ([PR#809](https://github.com/aidasoft/DD4hep/pull/809))
  - DDG4: Extend existing sensitive detectors to be used for GFlash parametrized fast simulations
  - DDG4: Remove legacy sensitive detectors, since they are no longer used by FCC

* 2021-04-15 Markus FRANK ([PR#808](https://github.com/aidasoft/DD4hep/pull/808))
  - Disable copy and move construction/assignment in Geant4 data
    See issue https://github.com/AIDASoft/DD4hep/issues/807
  - Adopt new naming convention for Geant4 assembly imprints
     See issue https://github.com/AIDASoft/DD4hep/issues/804
  - Add G4FastSimulationManagerProcess for GFlash

* 2021-04-12 Marko Petric ([PR#803](https://github.com/aidasoft/DD4hep/pull/803))
  - Fix bug in evaluator reported by Coverity

# v01-16-01

* 2021-03-26 Andre Sailer ([PR#799](https://github.com/AIDASoft/DD4hep/pull/799))
  - DDG4: flush the geant4 strstream buffer after run. fixes #798

* 2021-03-26 Marko Petric ([PR#793](https://github.com/AIDASoft/DD4hep/pull/793))
  - Account for possible units rounding bug in Tube creation (address #784 )

* 2021-03-23 Andre Sailer ([PR#797](https://github.com/AIDASoft/DD4hep/pull/797))
  - DDG4Dict: Adapt to changes in Root 6.24

* 2021-03-23 Andre Sailer ([PR#796](https://github.com/AIDASoft/DD4hep/pull/796))
  - RootDictionary: fix incompatibility with Root 6.24

* 2021-03-23 Andre Sailer ([PR#795](https://github.com/AIDASoft/DD4hep/pull/795))
  - Geant4Input: Add debug output for accepting or rejecting Particles

* 2021-03-14 Markus FRANK ([PR#794](https://github.com/AIDASoft/DD4hep/pull/794))
  - Address Coverity issues

* 2021-03-12 Marko Petric ([PR#792](https://github.com/AIDASoft/DD4hep/pull/792))
  - Use `CMAKE_SHARED_LIBRARY_SUFFIX` to define suffix of assimp libs
  - Define `BUILD_BYPRODUCTS` for compatibility with `ninja`

* 2021-03-12 Markus FRANK ([PR#791](https://github.com/AIDASoft/DD4hep/pull/791))
  - Remove a bunch of Coverity warnings.

* 2021-03-12 MarkusFrankATcernch ([PR#790](https://github.com/AIDASoft/DD4hep/pull/790))
  - update materialBudget utility
      -  allow to optionally use pseudo rapidity eta rather than polar angle

* 2021-03-12 Marko Petric ([PR#788](https://github.com/AIDASoft/DD4hep/pull/788))
  - Use flag `--as-needed` for GNU linkers

* 2021-03-11 Markus FRANK ([PR#789](https://github.com/AIDASoft/DD4hep/pull/789))
  - Fix several coverity warnings
  - Fix bug in extracting unsigned int/long from xml: conversion to unsigned values had a bug.
  - Remove unnecessary printout in Geant4Converter

# v01-16

* 2021-03-02 Markus FRANK ([PR#787](https://github.com/AIDASoft/DD4hep/pull/787))
  - Resolves #786. Also add an example to reproduce the Fix.
  - Add protection in Detector object against registering DetElements without placement
  - Modernize loop handling according to C++ 17 standards

* 2021-02-15 Andre Sailer ([PR#783](https://github.com/AIDASoft/DD4hep/pull/783))
  - Adapt to new ROOT mechanism for switching the unit system.
    Units can be switched now multiple times provided the units are unlocked in the TGeoManager.
    See TGeoManager::LockDefaultUnits(Bool_t new_value).
    This is only available for ROOT versions >= 6.22.08
  - Improve examples/Conditions. Allow for more complex dependencies. Not enabled by default.

* 2021-01-31 Markus FRANK ([PR#779](https://github.com/AIDASoft/DD4hep/pull/779))
  - Propagate changes in ComponentCast to the EDM module

* 2021-01-30 Markus FRANK ([PR#778](https://github.com/AIDASoft/DD4hep/pull/778))
  - Move the header DD4hep/detail/Grammar_parsed.h to DD4hep/GrammarParsed.h
  - Move the header DD4hep/detail/Grammar_unparsed.h to DD4hep/GrammarUnparsed.h
  - Try to improve type agnostic ABI cast. Works for down casts only.

* 2021-01-08 Markus FRANK ([PR#772](https://github.com/AIDASoft/DD4hep/pull/772))
  - This is the first release prepared to use Geant4 units (mm,ns,MeV). This compilation mode can be steered by a cmake flag: `-DDD4HEP_USE_GEANT4_UNITS=ON`. Once set, the flag is automatically propagated to depending projects in the generated `DD4hepConfig.cmake`. It programs TGeo to use the Geant4 units system. The unit system is applied also to depending quantities like interaction lengths etc.
  - Update some tests and ensure compatibility in the checks/reference files for both unit system. There is one caveat: Mesh-creation of shapes depends to some degree on the unit system, because mesh points are  removed depending on a tolerance value which is the same for both systems.
  - A fix had to be applied to propagate the flag `DD4HEP_BUILD_DEBUG` to depending projects.  This flag affects some object layouts and hence MUST be applied also to depending projects.
  - Remove inclusions of `Plugins.h` from being processed by rootcling. Plugins.h uses `#include <any>`, which cannot be processed.

* 2020-12-18 Marko Petric ([PR#771](https://github.com/AIDASoft/DD4hep/pull/771))
  - Expand list of cmake versions that have bug in detecting python version  (see AIDASoft/podio#162)

# v01-15

* 2020-12-08 Frank Gaede ([PR#740](https://github.com/AIDASoft/DD4hep/pull/740))
  - add back the  Geant4Output2EDM4hep plugin from EDM4hep
       - use optional flag `D4HEP_USE_EDM4HEP` to build this
       - requires podio and EDM4hep to be present
  - fix treatment of units in Geant4Output2EDM4hep
  - DDTest: add optional ddsim tests with edm4hep and lcio output (A.Sailer)
  - enable `D4HEP_USE_EDM4HEP` in CI for dev (A.Sailer)

* 2020-12-07 Christopher Jones ([PR#767](https://github.com/AIDASoft/DD4hep/pull/767))
  - Made internal classes used by Evaluator to be less stateful
  - Switch to using a read/write lock as modifications to the Evaluator are much less frequent than reads.
  - Added unit test for Evaluator

* 2020-12-04 Andre Sailer ([PR#766](https://github.com/AIDASoft/DD4hep/pull/766))
  - DDG4: hepmc3reader: add checks for read and skip success
  - DDTest: test hepmc3 reader, make lcio and hepmc3 reader tests depend on configuration.

* 2020-12-04 Andre Sailer ([PR#765](https://github.com/AIDASoft/DD4hep/pull/765))
  - DDG4: Geant4InputHandling: create particle with 4 vector (vecP, E), solves issue where the dynamic mass differs from the PDG mass (e.g., via particle.tbl / extraParticles), #760

* 2020-12-03 MarkusFrankATcernch ([PR#753](https://github.com/AIDASoft/DD4hep/pull/753))
  - Always use `CLHEP/Units/SystemOfUnits.h` and never `G4SystemOfUnits.hh`
    -  in `G4SystemOfUnits.hh`units are directly in the top level namespace
    - in `CLHEP/Units/SystemOfUnits.h` units are in the `CLHEP::` namespace
  - Remove all usage `using namespace CLHEP` and `using CLHEP::__some_unit__` to clarify which unit is used

* 2020-12-02 MarkusFrankATcernch ([PR#764](https://github.com/AIDASoft/DD4hep/pull/764))
  - Make scaled shapes includes conditional on Geant4 version (>=10.3)
  - Improve thread safety of expression evaluator

* 2020-12-02 Andre Sailer ([PR#754](https://github.com/AIDASoft/DD4hep/pull/754))
  - ddsim: fix problem with `--dumpSteeringFile` in python3
  - ddsim: fix issue in where isotrop was False, when distribution was set (python3)
  - ddsim: fix exception in exceptions for gun direction and position
  - ddsim: fix problem where `hepmc.useHepMC3` was always True by default
  - PluginManager: rename the listcomponents executable to listcomponents_dd4hep, to avoid clash with the Gaudi listcomponents. This is transparent for users of the dd4hep_add_plugin cmake macro.
  - DDG4Dict: remove `dd4hep::sim::Geant4InputAction::Particles;` as this is available under a different name, fixes warning
  - CMake: DD4hepConfig.cmake: use find_dependency with CONFIG for Geant4, TBB, ROOT, LCIO, and if needed CLHEP, to avoid accidental use of `Find<PACKAGE>.cmake` modules

* 2020-11-24 MarkusFrankATcernch ([PR#757](https://github.com/AIDASoft/DD4hep/pull/757))
  - Expression evaluation was not protected against race conditions when executing in multiple threads. We lock now the evaluation namespace with an associated lock when evaluating expression statements. Each evaluation call is wrapped and protected. This should ensure thread safety.

* 2020-11-24 Marko Petric ([PR#751](https://github.com/AIDASoft/DD4hep/pull/751))
  - Resolve which type of linker is used and assign proper linking flags

* 2020-11-21 Markus FRANK ([PR#756](https://github.com/AIDASoft/DD4hep/pull/756))
  - Remove from Geant4 conversion of scaled shapes artifacts of the prior implementation of reflections.
    This was a wrong implementation and should now be fixed.
    This PR should fix issue https://github.com/AIDASoft/DD4hep/issues/750
  - Introduce the Scale (based on TGeoScaledShape) as a separate shape om DD4hep.
  - Add test for scaled shape

* 2020-11-19 Marko Petric ([PR#749](https://github.com/AIDASoft/DD4hep/pull/749))
  - Add explanation of the system of units to the user manual

* 2020-11-19 MarkusFrankATcernch ([PR#748](https://github.com/AIDASoft/DD4hep/pull/748))
  - Review documentation
    o Add chapter to describe MC truth handling for DDG4
    o Review shape and shape plugin section in the DD4hep manual
  - Adapt ConeSegment shape plugin to allow for standard syntax
  - Fix Torus shape plugin and test 
  - Add copyright notice to various test files

* 2020-11-19 Ole Hansen ([PR#745](https://github.com/AIDASoft/DD4hep/pull/745))
  - Improve path handling in setup scripts, by avoiding duplicates in paths. Also support whitespaces in paths and don't add system paths to library paths on macOS

* 2020-11-19 Ole Hansen ([PR#743](https://github.com/AIDASoft/DD4hep/pull/743))
  - Fix compilation warnings from Apple Clang 12
  - Fix broken `t_CLICSiD_DDG4_g4geometry_scan_LONGTEST` test condition which always matched.

* 2020-11-18 Ole Hansen ([PR#744](https://github.com/AIDASoft/DD4hep/pull/744))
  - CMake: Fix regression that examples and example tests can now be built and run together with the main project

* 2020-11-16 Markus FRANK ([PR#747](https://github.com/AIDASoft/DD4hep/pull/747))
  - Add documentation of DDG4 Monte-Carlo truth handler
  - Add documentation of DDG4 ROOT output module

* 2020-11-13 Markus FRANK ([PR#742](https://github.com/AIDASoft/DD4hep/pull/742))
  - Add example for CMS CSC: tests divisions
  - Add example for CMS ECAL: tests reflections
  - Improve DDG4_MySensDet: Example illustrating how to have customized sensitive detectors and user defined hit classes with data saved to ROOT. Example corresponding to question raised in https://github.com/AIDASoft/DD4hep/issues/703
  The example also includes a small script to read back the data generated with this example:
  Command line usage:
     *  $> root.exe
     *  ....
     *  root [0] gSystem->Load("libDDG4Plugins.so");
     *  root [1] gSystem->Load("libDDG4_MySensDet.so");
     *  root [2] SomeExperiment::Dump::dumpData(<num-ebents>,<file-name>);
  
  - Remove the odd shadowing warning.
  - Improve visualization attributes:
    As reported by Sanhyung Ko (https://indico.cern.ch/event/967418/contributions/4075358/attachments/2128099/3583278/201009_shKo_dd4hep.pdf) the application of visual attributes to volumes was very resource intensive. 
    This should be fixed by asking for the transparent color only once at the level of the attribute rather then for each volume.

* 2020-11-11 Frank Gaede ([PR#738](https://github.com/AIDASoft/DD4hep/pull/738))
  - fix units in DDG4/LCIO conversions  
       - prepend namespace CLHEP where missing

* 2020-11-10 Markus FRANK ([PR#736](https://github.com/AIDASoft/DD4hep/pull/736))
  - Update DDCMS example to take into account new xml tags.
  - Improve some core object helpers

* 2020-11-06 Markus FRANK ([PR#734](https://github.com/AIDASoft/DD4hep/pull/734))
  - No new implementation for reflections. Still uses TGeo way with scaled shape.
    This implementation is not supposed to be used.
  - Added test to debug reflections

* 2020-11-05 Ianna Osborne ([PR#732](https://github.com/AIDASoft/DD4hep/pull/732))
  - Examples.DDCMS: add CMS EcalEndcap description to test reflected volumes

* 2020-11-03 Andre Sailer ([PR#731](https://github.com/AIDASoft/DD4hep/pull/731))
  - Tests: Always run AClick tests sequentially, fixes #730

* 2020-11-03 Andre Sailer ([PR#728](https://github.com/AIDASoft/DD4hep/pull/728))
  * CMake: fix python version compatibility check between python and root used for python. Add exception for CMake 3.17.1
  * Tests: fix some test configuration to run all tests after `-D DD4HEP_BUILD_EXAMPLES=ON`
  * Tests: fix tests for root 6.22.04 and master