# Category modeling History

See `CONTRIBUTING.rst` for details of **required** info/format for each entry,
which **must** added in reverse chronological order (newest at the top).
It must **not** be used as a substitute for writing good git commit messages!

-------------------------------------------------------------------------------

## 2026-03-05 John Allison (modeling-V11-03-09)
- G4PhysicalVolumeModel:
  - Build and maintain a private G4NavigationHistory.
    - Create a temporary G4TouchableHistory from it when required (i.e., when
      calling nested parameterisation ComputeMaterial()).

## 2026-03-03 John Apostolakis
- G4PhysicalVolumeModel.cc:
  - Replace helper class G4PhysicalVolumeModelTouchable with temporary 
    G4TouchableHistory object (when calling nested parameterisation.)

## 2025-04-13 John Allison (modeling-V11-03-08)
- G4PhysicalVolumeModel.cc:
  - Fix typo in ModelType.

## 2025-02-28 John Allison (modeling-V11-03-07)
- G4TrajectoryDrawerUtils.cc:
  - Trap trajectories with very long global times, e.g, products of long-lived
    radioactive isotopes.
    - Draw as non-time-sliced trajectories.

## 2025-02-24 John Allison (modeling-V11-03-06)
- G4ModelingParameters.hh:
  - Implement G4ModelingParameters::TimeParameters::operaator!=.
- G4TrajectoryDrawerUtils.cc"
  - Fix bug in fade algorithm.

## 2025-02-22 John Allison (modeling-V11-03-05)
- G4ModelingParameters.hh:
  - TimeParameters:
    - Adjust defaul values:
      - Set fade factor to 1 (maximum fading) - see G4TrajectoryDrawerUtils.cc.
      - Set head time display 2D x-coordinate to zero (centre).
        - 2D y-coordinate remains at -0.9 (bottom).
- G4TrajectoriesModel.cc:
  - DescribeYourselfTo(sceneHandler):
    - Draw display head time if requested and if time windowing is active.
      - This is outside the loop over trajectories - it is drawn only once per
        processing of the scene.
    - Remove Begin/EndDraw around the trajectories loop.
      - It restricted what could be drawn inside the loop, for example 2D text,
        and anyway doesn't seem to make much speed improvement.
- G4TrajectoryDrawerUtils.cc:
  - Add fading of trajectory slices if time windowing is active.
    - Makes trajectory slices look like little meteors streaking across
      the screen. 

## 2025-02-10 John Allison (modeling-V11-03-04)
- G4TrajectoryDrawerUtils.cc:
  - First version of generic time windowing of trajectory slices.
    - Draws only slices within the viewer time window.
    - Takes advantage of recent ability to access modeling parameters via
      static GetCurrentModelingParameters().
    - Also of recently added G4RichTrajectoryPoint::GetPre/PostStepPointGlobalTime().
    - Note: unless the viewer can handled time-sliced trajectories (only OGLS can
      do this at present), the viewer must request a kernel visit on change of
      viewer time window. 
- G4TrajectoryDrawByEncounteredVolume.cc, G4TrajectoryEncounteredVolumeFilter.cc:
  - Use G4VTrajectory::GetAttValues() instead of CreateAttValues().
    - GetAttValues() caches the att values and so speeds repeated visits.

## 2025-02-04 John Allison (modeling-V11-03-03)
- G4VModel:
  - Introduce static data member const G4ModelinParameters* fpCurrentMP
    and its static accessor, GetCurrentModelingParameters().
  - Its value is expected to be identical to fpMP set in the scene
    handler, but to avoid linking problems, it must *not* be set on
    the vis side; it must be set in modeling by any model that
    requires it, G4TrajectoriesModel.
- G4TrajectoriesModel.cc:
  - Call SetCurrentModelingParameters.

## 2025-02-01 John Allison (modeling-V11-03-02)
- G4TrajectoryDrawerUtils.cc:
  - Clang format (just formatting - no other changes).
- G4ModelingParameters.cc:
  - Coverity fix: uninitialised data member.

## 2025-01-28 John Allison (modeling-V11-03-01)
- G4ModelingParameters.hh and .icc:
  - Add struct TimeParameters to G4ModelingParameters.
     - This is a prerequisite for "Generic Time-Slicing" for the display of the time
      evolution of event(s). With that feature, the display of tracks moving through
      time will be available to all vis drivers. (Drivers will still be alllowed to
      implement their own time evolution.)
    - This MR simply adds the structure to modeling parameters and implements access
      functions for the use of future MRs.

## 2025-01-06 John Allison (modeling-V11-03-00)
- Co-works: visman-V11-03-00, interfaces-V11-03-00, opengl-V11-03-00,
  visQt3D-V11-03-00, vis_toolssg-V11-03-00, openinventor-V11-03-00,
  greps-V11-03-00.
- Re-instate the transparency slider (see lengthy explanation in management/History).
- G4ModelingParameters:
  - Add TransparencyByDepth and TransparencyByDepthOption.
- G4PhysicalVolumeModel.cc:
  - Rename some data members and access functions for clarity.
  - Distinguish fTotalDrawnTouchables and fTotalAllTouchables.
  - Add fMaxFullDepth (includes base path, i.e., from world volume).
  - Add code for processing transparency by depth.
  - Tidy - mainly improved indentation.

## 2024-10-22 John Allison (modeling-V11-02-05)
- G4PhysicalVolumeModel.cc:
  - Fixed some ragged indentations.

## 2024-10-16 John Allison (modeling-V11-02-04)
- G4TrajectoryDrawByEncounteredVolume.cc, G4TrajectoryEncounteredVolumeFilter.cc:
  - Replace check on trajectory type using dynamic_cast with a simple check
    on the existence on the required G4Att.

## 2024-08-31 John Allison (modeling-V11-02-03)
- More Coverity fixes

## 2024-07-17 John Allison (modeling-V11-02-02)
- Coverity fixes

## 2024-01-22 John Allison (modeling-V11-02-01)
- Coworks with visman-V11-02-04, greps-V11-02-00 and interfaces-V11-02-01.
- G4PhysicalVolumeModel:
  - Add data field "TotalTouchables" and access functions.

## 2024-01-16 John Allison (modeling-V11-02-00)
- Co-works with visman-V11-02-02 and interfaces-V11-02-00.
- G4TextModel:
  - Use single quote (') to delineate actual text in description.
    - This is so that normal quotes can be used in G4VisCommandSceneActivateModel.

## 2023-07-01 John Allison (modeling-V11-01-06)
- G4PhysicalVolumeModel: Introduce touchable count.
  - std::map<G4int,G4int>& GetNumberOfTouchables():
    - Returns number of touchables by depth of geometry tree.
    - Used in G4VViewer when deciding whether to expand scene tree.

## 2023-05-30 John Allison (modeling-V11-01-05)
- G4PhysicalVolumeModel.cc: Fix Coverity warnings.

## 2023-04-24 John Allison (modeling-V11-01-04)
- Coworks: visman-V11-01-09.
- These two tags implement "generic cutaways"...finally...after 20 years!!!
  - See extensive description in visualization/management/History.
- G4PhysicalVolumeModel.cc:
  - DescribeSolid: Improve tests for invalid Boolean solid in code for
    section and cutaway.
    - Algorithms based on G4SubtractionSolid::BoundingLimits and
      G4IntersectionSolid::BoundingLimits by Evgueni Tcherniaev.

## 2023-04-03 John Allison (modeling-V11-01-03)
- Bug fix: Initialise fFullPVPath.

## 2023-03-28 John Allison (modeling-V11-01-02)
- Add static utility G4PhysicalVolumeModel::GetPVNamePathString.

## 2023-02-12 John Allison (modeling-V11-01-01)
- G4VModel.hh
  - Remove unnecessary reference to G4PhysicalVolumeModel.
- G4CallbackModel:
  - Correct the description in the comments.
- G4PseudoScene:
  - Add G4VisAttributes.
    - This was always available, but never previously made onward
      available to sub-classes.

## 2022-12-13 John Allison (modeling-V11-01-00)
- G4TextModel: Fix transform.
  - The rotation part of the transform was being ignored. This impacted
    the implementation of /vis/scene/add/localAxes.
- G4AxesModel: Tidied.

## 2022-11-25 Gabriele Cosmo (modeling-V11-00-14)
- Fixed compilation warnings for implicit type conversions on macOS/XCode 14.1.

## 2022-11-06 John Allison (modeling-V11-00-13)
- Eliminate G4cerr and introduce G4warn.
  - `#define G4warn G4cout`
    - The above is temporary until a genuine G4warn output stream is
      implemented.
  - Change G4cerr to G4warn in all cases.
  - Change G4cout to G4warn in those cases where `verbosity >= warnings`.

## 2022-10-28 John Allison (modeling-V11-00-12)
- Implement generic cutaway.
  - G4PhysicalVolumeModel::DescribeSolid:
  - Simplify clipping, sectioning and cutaway code.

## 2022-09-19 John Allison (modeling-V11-00-11)
- G4Mesh:
  - A simple parameterisation may only be one level.
  - Nested parameterisations may be 2- or 3-level.

## 2022-06-09 Laurie Nevay (modeling-V11-00-10)
- Allow arrow proportions to be greater than 1/100. Produces more
  visible arrows for field visualisation and also obeys the input
  parameters more closely.

## 2022-05-23 John Allison (modeling-V11-00-09)
- Co-works with visman-V11-00-18.
- Simplify `G4Mesh`.
  - Now finds 1-deep rectangular meshes such as `G4PhantomParameterisation`.
  - Improve commenting in `G4Mesh.hh`. Consult `G4Mesh.hh` for further
    information.

## 2022-04-17 John Allison (modeling-V11-00-08)
- Co-works with `visman-V11-00-14`.
- Retire `G4BoundingSphereScene` and `G4PhysicalVolumeSearchScene`.
  - `G4BoundingSphereScene` is superseded by `G4BoundingExtentScene`.
    - `G4BoundingSphereScene` accumulated blinding spheres and often
      overestimated the extent of the scene.
    - `G4BoundingExtentScene` deals directly with extents, which makes
      it neater and more tightly estimates. the overall extent of the
      scene. It has existed and has been in normal use for some time. It
      takes advantage of developments in `G4VisExtent` - see
      modeling-V10-05-00 (19 February 2019).
  - `G4PhysicalVolumeSearchScene` is superseded by
    `G4PhysicalVolumesSearchScene` (note the extra 's').
    - `G4PhysicalVolumeSearchScene` found only the first occurrence of
      a physical volume.
    - `G4PhysicalVolumesSearchScene` finds all occurrences and returns
      a "findings vector". It has existed and has been in normal use
      for some time.
  - `G4PhysicalVolumesSearchScene`:
    - Remove last ambiguous and misleading argument in the constructor.
      - It was used only once in `G4VisCommandsSceneAdd.cc`
        (`/vis/scene/add/volume`) and a better way has been found in
        `visman-V11-00-14`.

## 2022-04-09 John Allison (modeling-V11-00-07)
- `G4Mesh`:
  - Add `fpParameterisedVolume` and accessor.
- `G4PhysicalVolumeModel`:
  - `G4PhysicalVolumeNodeID`: Add `Set` accessors.
  - For `AddCompound(mesh)`:
    - Provide an "artificial" node as an (optional) hook for anything that
      might be generated.

## 2022-04-03 John Allison (modeling-V11-00-06)
- `G4PseudoScene`:
  - Add `AddCompound(const G4Mesh&)`.
    - If special mesh rendering is set, this catches mesh candidates
      (certain types of parameterisations) and avoids descending into
      the parameterisations.
    - It is used in `G4PhysicalVolumeModel::CalculateExtent` (the
      parameterised volumes anyway are enclosed in the "container" volume).
- `G4PhysicalVolumeModel.cc`:
  - `SetSpecialMeshRendering(true);` to avoids traversing (certain
     types of) parameterisations (see above).
- `G4BoundingExtentScene.cc`:
  - Removed unnecessary blank line.

## 2022-03-30 John Allison (modeling-V11-00-05)
- `G4PhysicalVolumeModel.cc`: eliminate goto statements.

## 2022-02-02 John Allison (modeling-V11-00-04)
- G4Mesh: Programmed for parameterised tetrahedron mesh.

## 2022-01-28 Ben Morgan (modeling-V11-00-03)
- Replace `geant4_global_library_target` with direct file inclusion and
  call to `geant4_add_category` to define library build from source modules.

## 2021-12-16 John Allison (modeling-V11-00-02)
- G4Mesh:
  - Augment available data for 3D rectangular mesh.

## 2021-12-11 John Allison (modeling-V11-00-01)
- G4PhysicalVolumeModel:
  - Add LocalExtent and GlobalExtent to G4PhysicalVolumeModel::GetAttDefs.
  - G4PhysicalVolumeModel::TouchableProperties:
    - Add fTouchableFullPVPath.
- G4PhysicalVolumesSearchScene::Findings:
- G4PhysicalVolumesSearchScene::ProcessVolume:
- G4TouchablePropertiesScene::ProcessVolume: 
  - Migrate to the above (fTouchableFullPVPath).

## 2021-12-10 Ben Morgan (modeling-V11-00-00)
- Change to new Markdown History format

---

# History entries prior to 11.0

05 November 2021  John Allison  (modeling-V10-07-16)
- Fix bug in G4PhysicalVolumeModel::CalculateExtent.
  - The extent was being calculated solely in the reference frame of the
    top physical volume. It needs to be transformed into the global
    coordinate system.
  - This impacts views that contain more than one top physical volume, e.g:
    - if you `/vis/drawVolume <volume-name` and there are more than
      one instance (touchable) with that name;
    - if you `/vis/drawVolume /reg-exp/` and `reg-exp` identifies more
      than one volume;
    - if you `/vis/scene/add/volume <volume-name>` to an already existing
      scene;
    - if you `/vis/viewer/centreOn <volume-name>` or
      `/vis/viewer/centreOn /reg-exp/` (similarly `centreAndZoomInOn`)
      that identify more than one touchable with that name.

25 October 2021  Guy Barrand (modeling-V10-07-15)
- sources.cmake: declare G4PlotterModel.hh,.cc.
- G4PlotterModel.hh,.cc: a model to handle a G4Plotter in a scene.
- G4PseudoScene.hh: default implementation of AddPrimitive(const G4Plotter&).

10 October 2021  John Allison  (modeling-V10-07-14)
- As a result of Coverity warnings, improve the health of...
  - G4PhysicalVolumeModel:
    - Clean up tempVisAtts in case of found G4Mesh.
    - Hold current transform as object, not as a pointer.
  - G4TouchablePropertiesScene.cc:
    - Migrate to the above.

06 July 2021  John Allison  (modeling-V10-07-13)
- G4AxesModel.cc:
  o Fix model name (somehow forgot to set name, so it picked up a default
    name from the base class).

05 July 2021  John Allison  (modeling-V10-07-12)
- G4PhysicalVolumeModel:
  o Make CalculateExtent a public function.
  o G4PhysicalVolumeModel::Validate:
    . Avoid crash if volume no longer in physical volume store.
    . Improve warning message.

30 June 2021  John Allison  (modeling-V10-07-11)
- Requires greps-V10-07-09.
- Revise vis models.
  o Over time, the vis models have sprouted some inconsistencies. This
    is an attempt to rationalise them. The most significant model - used
    in all applications to draw the detector - is G4PhysicaVolumeModel. To
    handle all the options, G4PhysicalVolumeModel takes care of the
    transformation of any primitives that it generates. It ignores the
    transformation available in the base class, G4VModel. This revision
    brings all models in line with this policy.
  o This implies the following:
    . The data member G4VModel::fTransform and accessors are removed;
    . Those models that need to keep a transformation now have their own
      fTransform.
  o Note: This may also fix some Coverity warnings.
  o At the same time, we remove G4Scale and G4ScaleModel. G4Scale is an
    anomaly. It is not a "primitive" (obviously), but somehow, from the long
    distant past, it was implemented as though it was. These classes have been
    removed and /vis/scene/add/scale reimplemented with G4CallBackModel.

15 June 2021  John Allison  (modeling-V10-07-10)
- G4PhysicalVolumeModel.cc:
  o Move fFullPVPath.push_back earlier - fixes vis touchables bug.

07 June 2021  John Allison  (modeling-V10-07-09)
- Requires greps-V10-07-07 (new method AddCompound (const G4Mesh&...)).
- Introduce G4Mesh, a light class that encapsulates and validates a
  nested parameterisation, which we call a "mesh". If a valid mesh
  cannot be created out of this G4VPhysicalVolume* it will
  have a type "invalid". Then, usually, it may simply be destroyed.
  The overhead of an invalid attempt is expected to be small - all the
  same it should only be invoked if the user specifies mesh rendering.
- G4PseudoScene....
  o Implement new method AddCompound (const G4Mesh&
- G4ModelingParameters: Add data members and access functions:
    G4bool fSpecialMeshRendering;  // Request special rendering
    std::vector<PVNameCopyNo> fSpecialMeshVolumes;  // If empty, all meshes.
- G4PhysicalVolumeModel.hh:
  o Change the default for the "drawn" flag to "true" (the more usual
    case and therefore more efficient) in the nested class
    G4PhysicalVolumeNodeID.
- G4PhysicalVolumeModel.cc:
  o Add code for special mesh rendering, under control of user flag. If
    flag is set by the above commands, and if a volume is a "mesh" (a
    container for a nested parameterisation), invoke new method
    AddCompound (const G4Mesh&).

28 May 2021 Ben Morgan (modeling-V10-07-08)
- Migrate to modular CMake build

27 May 2021  John Allison  (modeling-V10-07-07)
- Minor fix to "current tag" ('.' changed to ':').

24 May 2021  John Allison  (modeling-V10-07-06)
- G4PhysicalVolumeModel.cc:
  o For the resultant of clipping, set the vis attributes of the original.

11 May 2021  John Allison  (modeling-V10-07-05)
- G4VModel:
  o Make SetTransform virtual.
- G4ArrowModel, G4AxesModel and G4TextModel:
  o Implement SetTransform.
  o Take care to apply to original model. For example, if SetTransform is
    called more than once it must apply to the original.

20 April 2021  John Allison  (modeling-V10-07-04)
- G4PseudoScene::ProcessVolume: Add G4Exception.

26 March 2021  John Allison  (modeling-V10-07-03)
- G4PhysicalVolumesSearchScene:
  o Allow user to limit the depth of descent during a geometry tree search.

12 March 2021  John Allison  (modeling-V10-07-02)
- G4PhysicalVolumeModel:
  o If opacity (alpha) == 0 (completely transparent), treat same
    as pVisAttribs->IsVisible(). Thus:
      G4bool markedVisible
      = pVisAttribs->IsVisible() && pVisAttribs->GetColour().GetAlpha() > 0;

02 January 2021  John Allison  (modeling-V10-07-01)
- G4PhysicalVolumeModel.cc:
  o Simplify validation. The old way sometimes consumes much CPU.

29 December 2020  John Allison  (modeling-V10-07-00)
- G4VFieldModel: Change concept of choice of data points:
  o fNDataPointsPerMaxHalfScene becomes fNDataPointsPerMaxHalfExtent.
  o Hitherto, this model simply checked that a data point was within the
    extent. Now it uses the extent to determine the datapoint spacing.
  o Note: If fExtentForField is null, the used extent is that of the
    current scene. Otherwise it uses that supplied by the user.

20 October 2020  Jonathan Madsen (modeling-V10-06-05)
- Implemented G4RunManagerFactory::GetMasterRunManager()

18 September 2020  John Allison  (modeling-V10-06-04)
- Part of vis-V10-06-07.
- G4PhysicalVolumeModel.cc:
  o Pick up default vis attributes.
  o Improve operator<< G4PhysicalVolumeModel::G4PhysicalVolumeNodeID

04 August 2020. John Allison  (modeling-V10-06-03)
- G4PhysicalVolumeModel:
  o Introduce G4PhysicalVolumeModel::G4PhysicalVolumeNodeID::operator!= and ==.
  o G4PhysicalVolumeModel::G4PhysicalVolumeNodeID:
    . Change default for flag "drawn" to false. It is set to true in
      G4PhysicalVolumeModel::DescribeAndDescend for full path:
        fFullPVPath.back().SetDrawn(thisToBeDrawn);
      and for drawn path:
        fDrawnPVPath.push_back
          (G4PhysicalVolumeNodeID
          (fpCurrentPV,copyNo,fCurrentDepth,*fpCurrentTransform,thisToBeDrawn));
      for volumes that are drawn.
- G4PhysicalVolumesSearchScene.cc:
  o G4PhysicalVolumesSearchScene::ProcessVolume:
    . Make sure base path is also marked as "not drawn".

07 April 2020. John Allison  (modeling-V10-06-02)
* G4BoundingExtentScene.cc:
  * Minor tidy: Use G4VisExtent::GetNullExtent (rather than
    default constructor).

04 March 2020. John Allison  (modeling-V10-06-01)
- G4AttributeFilterT.hh:
  o Suppress warnings while filter not fully established.

12 December 2019 B. Morgan (modeling-V10-06-00)
- Cleanup CMake build, removing obsolete granular library option and
  explicit include_directories.

19 November 2019 Gabriele Cosmo (modeling-V10-05-11)
- Fixed more cases of implicit type conversions.

15 November 2019 Gabriele Cosmo (modeling-V10-05-10)
- Fixed cases of implicit type conversions from size_t to G4int.

19 September 2019  Makoto Asai (modeling-V10-05-09)
- G4PSHitsModel.cc
  o Namespace scope is added to MeshScoreMap
  o Co-working with detutils-V10-05-01

29 August 2019  John Allison (modeling-V10-05-08)
- Part of vis-V10-05-24.
- Add G4TessellatedSolid to list of solids that may be specially treated

16 July 2019  John Allison  (modeling-V10-05-07)
- Part of vis-V10-05-22.
- G4CallbackModel.hh:
  o Include modelling parameters in passed arguments.

05 July 2019  John Allison  (modeling-V10-05-06)
- Part of vis-V10-05-21.
- Rationalise trajectory line drawing.
  o There is a flag - DrawLine - which controls whether a trajectory
    should be drawn at all:
      /vis/modeling/trajectories/drawByCharge-0/default/setDrawLine
    but there is also a lineVisible command, which should do the same.:
      /vis/modeling/trajectories/drawByCharge-0/default/setLineVisible
    This is fixed in this tag.
  o I think there was some confusion between "visible" as used by filtering
    and "visible" as used in drawing. For example in
      G4TrajectoryDrawByCharge::Draw
      (const G4VTrajectory& traj, const G4bool& /*visible*/)
    the argument visible is the former sense but it is (was) interpreted as
    visible in the latter sense. As you see, I have suppressed its use in
    this and similar functions.

13 June 2019  John Allison  (modeling-V10-05-04)
- Part of vis-V10-05-20.
- G4ModelingParameters:
  o Add cloud to enum options and updated operators != and <<:
  o Similarly added to VisAttributesSignifier
- G4PhysicalVolumeModel.cc:
  o Handle new VisAttributesSignifiers.

10 June 2019  John Allison  (modeling-V10-05-03)
- Part of vis-V10-05-19.
- G4ArrowModel: Further use of const and introduce further protection.
- G4VFieldModel.cc: Further use of const.

29 May 2019  John Allison  (modeling-V10-05-02)
- Improve field modelling:
  o G4VFieldModel: Improve so even the smallest non-zero sample is visible:
    . Values < 10% max are drawn as lines of width 2.
    . Values < 1% max have their length fixed at 1% max.
    . Reverse colour code. Now, where f = fieldStrength/maxStrength:
        0 -> f/2 -> f is coded as red -> green -> blue.
      For a uniform field this means arrows are now blue instead of red.
  o G4ArrowModel:
    . Place checks on dimensions to prevent G4Exceptions in used solids.
    . Model arrow head as G4Tet.
- G4PhysicalVolumeModel.cc:
  o Improve printing from operator<< for nodeID path.

04 April 2019  John Allison  (modeling-V10-05-01)
- Co-works visman-V10-05-04.
- Final (for now) corrections to /vis/viewer/set/sectionPlane.
  Still some strange behaviour in small fraction of cases. See
  comments in G4PhysicalVolumeModel::DescribeSolid around line 748.

24 March 2019  John Allison  (modeling-V10-05-00)
- Fix bug in /vis/viewer/set/sectionPlane.
  Involves using G4DisplacedSolid instead of plain G4VSolid.

18 March 2019  Gabriele Cosmo
- Included in vis-V10-05-15
- Corrected few typos comments.

24 February 2019  John Allison
- Included in vis-V10-05-13
- Add constructor to G4PhysicalVolumesSearchScene::Findings from
  G4PhysicalVolumeModel::TouchableProperties.
- Fix bug in overlap drawing of parameterised volumes.

19 February 2019  John Allison
- Included in vis-V10-05-12
- Introduced G4BoundingExtentScene. This allows one to accumulate extents
  using the newly introduced G4VisExtent::Transform and is a better way
  of determining the overall extent of a scene (or of any set of extents)
  than by the bounding sphere approach.
- G4VFieldModel, G4ElectricFieldModel, G4MagneticFieldModel:
  o Introduced volume for field.
- G4VModel: Introduced GetTransformedExtent. This calculates the extent as
  it appears to the user, based on the local extent and the transformation.
- G4PhysicalVolumeModel:
  o Use G4BoundingExtentScene instead of G4BoundingSphereScene.
  o Fix bug whereby the local extent was incorrectly calculated - in fact
    it was the transformed extent. Corresponding corrections to all cases
    where the extent is needed, for example, in defining the view
    parameters, have been made in this commit.

13 February 2019  John Allison
- Included in vis-V10-05-11
- Implement /vis/set/extentForField - see visualisation/History.

08 February 2019  John Allison
- Included in vis-V10-05-09
- Fix Coverity warnings.

31 January 2019  Michael Kelsey
- Included in vis-V01-05-08

- G4VFieldModel.hh/cc: NEW intermediate base class for magnetic, electric
  and gravitational fields.  Contains all of DescribeYourselfTo() moved from
  G4MagneticFieldModel, plus a pure virtual function (GetFieldAtLocation) to
  fetch the field vector (differently by each subclass).  Constructor now
  takes two strings to let subclasses customize diagnostics and arrow labels.

- G4ElectricFieldModel:  NEW concrete class implementing GetFieldAtLocation()
  for electric field access.

- G4MagneticFieldModel:  Move all of DescribeYourselfTo() to new base class
  G4VFieldModel.  Implement old contents of "if (field) { ..." block as new
  GetFieldAtLocation() function.

29 January 2019  John Allison
- Included in vis-V10-05-06
- G4PhysicalVolumeModel.cc:
  o If the top volume is parameterised or a replica describe only one
    of them, namely the one specified by the copy number.

26 January 2019  John Allison
- Included in vis-V10-05-06
- Fix calculation of vis extent for parameterisations. This involved
  extending G4PhysicalVolumeModel::TouchableProperties to include copy
  number and initialising the copy number in the constructor. Then in
  G4PhysicalVolumeModel::CalculateExtent solid->ComputeDimensions is
  invoked if it is a parameterised volume.
- Some minor tidying.

02 January 2019  John Allison
- Included in vis-V10-05-00.
- G4PhysicalVolumeModel.cc: Add volume count (but comment out printing).

14 November 2018  John Allison  (modeling-V10-04-18)
- G4PhysicalVolumeModel.cc: Fix Coverity warning.

08 November 2018  John Allison  (modeling-V10-04-17)
- G4LogicalVolumeModel.cc:
  o Overlap checking now in text and drawing.

07 November 2018  John Allison  (modeling-V10-04-16)
- G4PhysicalVolumeModel.cc:
  o Add BasePVPath to G4Atts.
  o Tidied.
- G4LogicalVolumeModel.cc:
  o Overlap checking only in text output at present.

24 October 2018  John Allison  (modeling-V10-04-15)
- G4TouchableUtils:
  o Remove FindGlobalTransform, introduce FindTouchableProperties. The
    global transform is in properties.fTouchableGlobalTransform.
- Add G4TouchablePropertiesScene.
- Delete G4TouchableDumpScene, G4TouchableGlobalTransformScene.
- sources.cmake: Modify for above additions and deletions.
- G4PhysicalVolumesSearchScene::Matcher:
  o Improve logic and safety.
  o Add G4Exception(...JustWarning...)
- G4PhysicalVolumeModel:
  o Comment out resets at end of DescribeYourselfTo(). Shouldn't be
    necessary - they should all be maintained. In fact, zeroing the LV
    pointer is plain wrong and causes error in GetAttvalues
  o Introduce a static function GetPVNameCopyNoPath  to convert PVPath
    to PVNameCopyNoPath:
  o Add BasePVPath to G4Atts.
- G4ModelingParameters:
  o Remove constructors that take PVPath as an argument. Caused circular
    dependency with G4PhysicalVolumeModel.
- G4AxesModel: Correct exception number.

17 October 2018  John Allison  (modeling-V10-04-14)
- G4PhysicalVolumesSearchScene: Attempt fix for Windows compiler error.

15 October 2018  John Allison  (modeling-V10-04-13)
- G4PhysicalVolumesSearchScene: Add regex search.
  o Match the string with the required match. The latter can be of the form
    "/regexp/", where regexp is a regular expression (see C++ regex),
    or a plain string, in which case there must be an exact match.

8 October 2018  John Allison
- G4MagneticFieldModel: Improve global description.

6 October 2018  John Allison  (modeling-V10-04-12)
- G4TrajectoriesModel: Improve description.

11 September 2018  John Allison  (modeling-V10-04-11)
- G4VisTrajContext.cc: Initialise fLineWidth(1.).

10 September 2018  John Allison  (modeling-V10-04-10)
- Add G4PhysicalVolumesSearchScene.
  o This returns all occurrences of a physical volume.

5 September 2018  John Allison
- G4PhysicalVolumeModel: More minor tidying.

4 September 2018  John Allison
- G4PhysicalVolumeModel: Minor tidying.

3 September 2018  John Allison  (modeling-V10-04-09)
- G4PhysicalVolumeSearchScene:
  o Remove fetch and store of unused logical volume pointer.

31 August 2018  John Allison  (modeling-V10-04-08)
- Add setLineWidth for trajectory models.

29 August 2018  John Allison  (modeling-V10-04-07)
- G4LogicalVolumeModel:
  o Add overlap checking (printing only for now).
    . Avoid multiple printing of overlaps. Print only first time for
      a given instantiation of G4LogicalVolume.
- Add G4TouchableGlobalTransformScene:
  o Return a pointer to the global transform of a touchable.
- Add G4TouchableUtils:
  o Implement G4TouchableUtils::FindGlobalTransform. (Uses
    G4TouchableGlobalTransformScene.) Typical use:
      G4ModelingParameters::PVNameCopyNoPath path;
      // Specify the complete path of the touchable by a succession of
      // name,copyNo pairs or pointer,copyNo pairs.
      path.push_back(G4ModelingParameters::PVNameCopyNo("World",0));
      path.push_back(G4ModelingParameters::PVNameCopyNo("Envelope",0));
      .. etc., until touchable completely specified
      const G4Transform3D* pGlobalTransform =
      G4TouchableUtils::FindGlobalTransform(path);

11 June 2018  John Allison  (modeling-V10-04-06)
- G4PhysicalVolumeModel.cc: Fix Coverity warning.
  o Unnecessary check on pointer.

24 May 2018  John Allison  (modeling-V10-04-05)
- G4LogicalVolumeModel:
  o Add fCheckOverlaps flag. Calls CheckOverlaps for each G4PVPlacement.
  o Note: G4PVParameterised not coded in this tag.
- G4TrajectoryDrawByEncounteredVolume.cc,
  G4TrajectoryEncounteredVolumeFilter.cc:
  o Fix gcc-8 warnings.

30 April 2018  John Allison
- G4PhysicalVolumeModel.cc: Colour by density: improved comments.

24 April 2018  John Allison  (modeling-V10-04-04)
- G4ModelingParameters.cc: Small bug fix.

24 April 2018  John Allison  (modeling-V10-04-03)
- Implement /vis/viewer/set/colourByDensity.

11th March 2018  John Allison  (modeling-V10-04-02)
- G4PhysicalVolumeMassScene.cc: Protect case of no material in parallel world.

19th December 2017  Gabriele Cosmo  (modeling-V10-04-01)
- Fixed self-consistency in G4AttValueFilterT header (missing #include).
  Thanks to Raphael Isemann for reporting this.

12th December 2017  John Allison  (modeling-V10-04-00)
- G4TrajectoryDrawerUtils.cc: Improvement to an informational message.

13th September 2017  John Allison  (modeling-V10-03-08)
- G4ModelingParameters.cc, G4PhysicalVolumeModel.cc:
  Reverted default number of line segments per circle to 24.
  (72 lines per circle gives trouble in the Boolean Processor, so until that
  is fixed we revert to 24.)

14th May 2017  John Allison (modeling-V10-03-07)
- G4GPSModel: Added user-selectable colour.

3rd May 2017  John Allison (modeling-V10-03-06)
- Needs event-V10-03-01.
- Completed G4GPSModel for visualisation of General Particle Source. Can
  be used with command /vis/scene/add/gps.

3rd May 2017  John Allison (modeling-V10-03-05)
- Added prototype/skeleton G4GPSModel.
- G4PhysicalVolumeModel::Validate:
  o Check world pointer (can be null if geometry has been cleared/destroyed).

19th April 2017  John Allison (modeling-V10-03-01)
- Added G4ModelingParameters::PVPointerCopyNo.

9th December 2016  John Allison (modeling-V10-03-00)
- Coworks with visman-V10-03-00.
- G4MagneticFieldModel: Augmented to take lineSegmentsPerCircle.
  Default is 6 for rapid yet adequate drawing, but this my be changed
  with /vis/set/arrow3DLineSegmentsPerCircle.

3rd November 2016  John Allison (modeling-V10-02-17)
- G4ModelingParameters and G4PhysicalVolumeModel:
  Changed default number of line segments per circle from 24 to 72.

2nd November 2016  John Allison (modeling-V10-02-16)
- G4ArrowModel: Default lines per circle = 6.
  But... there is no way to change this at run time with a
  UI command.  The following commands would have to be augmented:
    /vis/scene/add/arrow
    /vis/scene/add/axes
    /vis/scene/add/magneticField
  or a new general command added such as
    /vis/set/arrowLineSegmentsPerCircle

29th September 2016  John Allison (modeling-V10-02-15)
- G4PhysicalVolumeModel:
  o Delayed creation of modifiedVisAtts so that not created at all
    if there are no vis attributes modifiers.
  o Added std::ostream& operator<< (std::ostream& os,
    const std::vector<G4PhysicalVolumeModel::G4PhysicalVolumeNodeID>& path)
  o Modified so path can be copied and pasted into
   /vis/set/touchable command:
    std::ostream& operator<< (std::ostream& os,
    const G4PhysicalVolumeModel::G4PhysicalVolumeNodeID& node)

19th September 2016  John Allison (modeling-V10-02-14)
- G4PhysicalVolumeModel.cc:
  o Used static to ensure a plausible vis attributes pointer.
    Note: G4VSceneHandler::PreAddSolid requires a G4VisAttributes
    object, so we have to provide one - we choose the default
    G4VisAttributes if no other is specified.

19th September 2016  John Allison (modeling-V10-02-13)
- Moved Vis Attributes Modifiers (VAMs) back from G4ViewParameters,
  reversing modeling-V10-02-11.
- Reversed modeling-V10-02-12.

12th September 2016  John Allison (modeling-V10-02-12)
- G4ModelingParameters.cc:
  o Changed output of
    std::ostream& operator <<
    (std::ostream& os, const G4ModelingParameters::PVNameCopyNoPath& path)
    to correspond to arguments of /vis/set/touchable.

11th September 2016  John Allison (modeling-V10-02-11)
- G4ModelingParameters:
  o Removed Vis Attributes Modifiers (VAMs).
  o VAMs are now entirely in G4ViewParameters and dealt with
    in G4VViewer::GetApplicableVisAttributes.
- G4PhysicalVolumeModel.cc: Removed VAM code.

8th September 2016  John Allison
- G4PhysicalVolumeModel.cc: Commented out VAM code.

31st August 2016  John Allison (modeling-V10-02-10)
- Co-works greps-V10-02-05.
- G4PseudoScene.hh:
  o Added
      void AddSolid (const G4Orb&);
      void AddSolid (const G4Ellipsoid&);
    to conform to greps-V10-02-05.
  o Tidied.
- G4PhysicalVolumeMassScene:
  o Changed to inherit G4PseudoScene.
  o Changed AccrueMass to ProcessVolume to conform to G4PseudoScene.
  o Added
      void AddSolid (const G4Orb&);
      void AddSolid (const G4Ellipsoid&);
    to conform to greps-V10-02-05.
  o Tidied.

14th August 2016  John Allison  (modeling-V10-02-07)
- G4TrajectoriesModel::DescribeYourselfTo:
  o Return if run or event not found.

7th August 2016  John Allison  (modeling-V10-02-06 needs greps-V10-02-02)
- G4ModelingParameters:
  o Added changes in Vis Att Modifiers for new flag IsForceDrawingStyle.
- G4PhysicalVolumeModel:
  o Takes account of new flag IsForceDrawingStyle.

20th July 2016  John Allison  (modeling-V10-02-05)
- Introduced drawing and filtering by encountered volume.  I.e.,
    /vis/modeling/trajectories/create/drawByEncounteredVolume
    /vis/filtering/trajectories/create/encounteredVolumeFilter
  and their associated commands.  They replace the TouchedVolume
  commands introduced in modeling-V10-02-02.

2nd May 2016  John Allison  (modeling-V10-02-04)
- G4PhysicalVolumeModel.cc: Fixed gcc-6.1 warning.

5th April 2016  John Allison  (modeling-V10-02-03)
- G4TrajectoryDrawByOriginVolume.cc: Tidied #include statements.

15th February 2016  John Allison  (modeling-V10-02-02)
- Introduced drawing and filtering by touched volume.  I.e.,
    /vis/modeling/trajectories/create/drawByTouchedVolume
    /vis/filtering/trajectories/create/touchedVolumeFilter
  and their associated commands.  Note that this
  selects only by a single string, the physical volume name.  If there
  are more than one physical volumes with that name then any trajectory
  touching any one of those volumes will be selected.  If the user sets
  more than one physical volume name (by using the set command more than
  once) the trajectory will be selected if it touches either of those
  volumes and which of the attributes (e.g., colour) associated with
  those volumes is chosen is undefined, but one will be chosen.
  A more comprehensive facility would allow the user to select by
  touched touchable, i.e., by the full path and copy numbers of the
  physical volume - but that is a job for the future if a use case arises.
  o G4TrajectoryModelFactories.hh/cc:
    Added G4TrajectoryDrawByTouchedVolumeFactory.
  o G4TrajectoryFilterFactories.hh/cc:
    Added G4TrajectoryTouchedVolumeFilterFactory.
  o Added new files and classes:
    G4TrajectoryDrawByTouchedVolume.hh/cc
    G4TrajectoryTouchedVolumeFilter.hh/cc
  o G4ModelColourMap.hh: Added new access function:
    const std::map<T, G4Colour>& GetBasicMap() const;
    to allow access to the T objects (which are G4String objects,
    physical volume name(s) in this case) that have been set.
  o sources.make: Added:
    G4TrajectoryDrawByTouchedVolume.hh
    G4TrajectoryTouchedVolumeFilter.hh
    G4TrajectoryDrawByTouchedVolume.cc
    G4TrajectoryTouchedVolumeFilter.cc
- G4TrajectoryDrawByOriginVolume.cc: Tidied.

26th January 2016  John Allison  (modeling-V10-02-01)
- G4ModelingParameters.hh: Added VisAttributesModifier Set commands.

26th January 2016  John Allison  (modeling-V10-02-00)
- G4TrajectoryDrawByOriginVolume::Draw and
  G4TrajectoryOriginVolumeFilter::Evaluate:
  Added specific arguments to LocateGlobalPointAndSetup to handle
  multithreading mode.

2nd October 2015  John Allison  (modeling-V10-01-05)
- G4MagneticFieldModel.cc: Cosmetic improvements.

1st October 2015  John Allison  (modeling-V10-01-04)
- Co-works with visman-V10-01-18
- Added "light" representation to G4MagneticFieldModel.

30th July 2015  John Allison  (modeling-V10-01-03)
- G4PhysicalVolumeSearchScene.cc: Minor improvement.
  o Replaced an assignment by a reference.

19th May 2015  Laurent Garnier  (modeling-V10-01-02)
- G4PhysicalVolumeSearchScene: Optimize ProcessVolume() by
  o setting variables only if needed
  o comparing string lenght before comparing all string

7th March 2015  John Allison  (modeling-V10-01-01)
- G4PhysicalVolumeModel: Add GetCurrentTransform().
- G4PhysicalVolumeModel::CreateCurrentAttValues():
  o Add local (and keep global) transformation.
- G4TouchableDumpScene.cc: Add polyhedron dump.

2nd February 2015  Gabriele Cosmo  (modeling-V10-01-00)
- Fix to sources.cmake script to include missing dependency on external library.

28th November 2014  John Allison  (modeling-V10-00-12)
- G4TrajectoriesModel.cc: Tidied.

29th October 2014  Makoto Asai (modeling-V10-00-11)
- G4TrajectoriesModel.cc: Further fix.

27th October 2014  Makoto Asai (modeling-V10-00-10)
- G4TrajectoriesModel.cc: Protect against incorrect casting if G4RunManager
  base class is used in multithreaded Geant4 installation.

22nd October 2014  Laurent Garnier  (modeling-V10-00-09 require greps-V10-00-08)
- G4ModelingParameters.cc
  o Change constant in .cc nSidesMin by GetMinLineSegmentsPerCircle() in the G4VisAttribute

22nd October 2014  John Allison  (modeling-V10-00-08)
- G4TrajectoriesModel.cc: Get appropriate run manager in MT mode.

11th August 2014  John Allison  (modeling-V10-00-07)
- Corrected date. modeling-V10-00-06 should be August.

9th July 2014  John Allison  (modeling-V10-00-06)
- G4AxesModel: Added a parameter for text size.  (Default 10 pixels.)
- G4TrajectoryDrawerUtils.cc and G4TouchableDumpScene.cc:
  o Fixed small memory leak.  (AttValues must be deleted by the user
    after use.)

19th May 2014  John Allison  (modeling-V10-00-05)
- Introduced G4TouchableDumpScene.
- Introduced G4PseudoScene.  The following now inherit it:
  o G4PhysicalVolumeSearchScene
  o G4BoundingSphereScene
  o G4TouchableDumpScene
- G4PhysicalVolumeModel
  o Allow instantiation of an empty model via the default constructor so
    that it can be used, for example, to get the G4AttDefs.  If it
    proves to be a problem we might have to disallow it again, but it is
    unlikley to be used except by visualisation experts.  See, for example,
    /vis/list, where it is used simply to get a list of G4AttDefs
  o Introduced Abort - all further geometry traversal is stopped.  (This
    is useful in G4TouchableDumpScene - once the required touchable is found
    there is no need to continue.)
  o Tidied.

6th March 2014  John Allison  (modeling-V10-00-04)
- G4PhysicalVolumeModel.cc:
  o More careful protection of zero pointers in constructor.

26th January 2014  John Allison  (modeling-V10-00-02)
- GNUmakefile: Added dependency on run category.
- G4PhysicalVolumeModel:
  o Augmented constructor to set sensible values of some data members,
    namely fpCurrentPV, fpCurrentLV, fpCurrentMaterial and
    fpCurrentTransform, so that CreateCurrentAttValues gives the G4Atts
    of the top volume if called without any further processing.

23rd January 2014  John Allison  (modeling-V10-00-01)
- G4TrajectoriesModel:
  o Add run ID.
  o Initialise fRunID and fEventID to -1.

13th January 2014  John Allison  (modeling-V10-00-00)
- Requires greps-V10-00-01.
- G4TrajectoryDrawByAttribute:
  o Migrated to operator<< for const reference G4AttDefs map.
- G4TrajectoriesModel:
  o Added SetCurrentTrajectory and SetEventID.

15th November 2013  John Allison  (modeling-V09-06-22)
- Some changes as suggested by PVS.

6th November 2013  John Allison  (modeling-V09-06-21)
- G4ArrowModel.cc: Tidied.

30th October 2013  Tatiana Nikitina  (modeling-V09-06-20)
- Make use of G4GenericPolycone in G4ArrowModel.
  Coworks with tag "geom-specific-V09-06-22".

30th September 2013  John Allison  (modeling-V09-06-19)
- Re-tagged after clean-up by Gunter and Mke.

27th September 2013  Michael Kelsey (modeling-V09-06-18)
- G4MagneticFieldModel.hh:  Remove expanded '$'Id'$' value and re-commit to
  (hopefully!) synchronize SVN state and eliminate "Modified" warnings in
  CDash.

21st September 2013  John Allison  (modeling-V09-06-17)
- G4MagneticFieldModel: Fix compiler warnings.

20th September 2013  John Allison  (modeling-V09-06-16)
- G4MagneticFieldModel: Added '$'Id'$' functionality.

2nd September 2013  John Allison
- G4MagneticFieldModel.cc:
  o Allowed for scene with extent not necessarily equal in x, y and z.

30th August 2013  John Allison  (modeling-V09-06-15)
- GNUmakefile: Added geometry/magneticfield/include.

29th August 2013  John Allison  (modeling-V09-06-14)
- G4MagneticFieldModel.cc: Fixed a corrupted file (SVN glitch?).

27th August 2013  John Allison  (modeling-V09-06-13)
- G4MagneticFieldModel:
  o Removed diagnostic print statements.
  o Note: Remaining print statements need converting to G4Exception.

26th August 2013  John Allison  (modeling-V09-06-12)
- G4MagneticFieldModel: Variable no. of data points per half scene.

25th August 2013  John Allison  (modeling-V09-06-11)
- G4MagneticFieldModel: Bug fix.

25th August 2013  John Allison  (modeling-V09-06-10)
- G4MagneticFieldModel: First attempt.

24th August 2013  John Allison  (modeling-V09-06-09 coworks visman-V09-06-11)
- Removed G4FlavoredParallelWorldModel.

18th August 2013  John Allison  (modeling-V09-06-08 requires greps-V09-06-06)
- Added skeleton G4MagneticFieldModel.

16th June 2013  John Allison  (modeling-V09-06-07)
- G4ModelingParameters: Small bug fix to previous tag.

10th June 2013  John Allison  (modeling-V09-06-06)
- G4ModelingParameters:
  o Replaced PVNameCopyNoPathNotEqual by appropriate operator!=.
  o Replaced VAMSNotEqual by appropriate operator!=.

29th May 2013  John Allison  (modeling-V09-06-05)
- G4PhysicalVolumeModel.cc: Bug fix for vis attribute modifying (VAM).
  (The boolean copyForVAM was not being reset after use.)

26th March 2013  John Allison  (modeling-V09-06-04)
- G4TrajectoryDrawByAttribute.cc: Improved G4Exception messages.

24th February 2013  John Allison  (modeling-V09-06-03)
- G4FlavoredParallelWorldModel:
  o Removed unused field as warned by new clang compiler.

14th January 2013  John Allison  (modeling-V09-06-02)
- G4ArrowModel, G4AxesModel:
  o Coverity fixes.

12th January 2013  John Allison  (modeling-V09-06-01)
- Coverity fixes:
  o G4PhysicalVolumeModel, G4TrajectoriesModel.
- Added verbosity flag for G4PhysicalVolumeSearchScene to reduce verbiage:
  o G4PhysicalVolumeModel, G4PhysicalVolumeSearchScene.

2nd December 2012  John Allison  (modeling-V09-06-00)
  o Removed NURBS and references to i_mode.

24th October 2012  John Allison  (modeling-V09-05-22)
- G4ModelingParameters:
  o Added fVisAttributesModifiers to operator<< and operator!=.
  o Added static functions VAMSNotEqual and PVNameCopyNoPathNotEqual to
    facilitate the above.
- G4PhysicalVolumeModel:
  o Allowed default constructor.  fpTopPV defaults to 0, checked with
    G4Exception(…FatalException…) in DescribeYourselfTo.  This allows
    one to instantiate a dummy so that one can print AttDefs, for example.

11th October 2012  John Allison  (modeling-V09-05-21)
- G4PhysicalVolumeModel and G4ModelingParameters:
  o Tidying.

9th October 2012  John Allison  (modeling-V09-05-20)
- G4PhysicalVolumeModel and G4ModelingParameters:
  o Moved code for converting PVPath to the simpler version from
    G4PhysicalVolumeModel (in modeling-V09-05-19) to a new
    constructor of G4ModelingParameters::VisAttributesModifier.

9th October 2012  John Allison  (modeling-V09-05-19)
- G4PhysicalVolumeModel:
  o Added GetFullPVNameCopyNoPath, which converts fFullPVPath into a
    simpler (full) path for G4ModelingParameters and G4ViewParameters.

8th October 2012  John Allison  (modeling-V09-05-18)
- G4PhysicalVolumeModel.cc: Removed debug printing.
- G4ModelingParameters.cc: Improved operator<< for PVNameCopyNoPath.

8th October 2012  John Allison  (modeling-V09-05-17)
- G4ModelingParameters:
  o Further refinement to interface for /vis/touchable/set/...
  o Added operator<< for PVNameCopyNoPath.

8th October 2012  John Allison  (modeling-V09-05-16)
- G4ModelingParameters:
  o Refined interface for /vis/touchable/set/...
- G4PhysicalVolumeModel:
  o Added code for /vis/touchable/set/...

7th October 2012  John Allison  (modeling-V09-05-15)
- G4ModelingParameters:
  o Added enums and a nested class for communicating a modification to the vis
    attributes for a specfic touchable defined by PVNameCopyNoPath, to be used
    by new commands, /vis/touchable/set/...

6th October 2012  John Allison  (modeling-V09-05-14)
- G4PhysicalVolumeModel:
  o Added SetBaseFullPVPath.  The base full path is the full path of the top
    physical volume (actually the full path of the mother of the top physical
    volume), so that even if a user issues "/vis/drawVolume sub-detector", the
    full path includes the base full path, i.e., the full path up to the world
    volume.
- G4PhysicalVolumeSearchScene:
  o Added GetFoundFullPVPath.

1st October 2012  John Allison  (modeling-V09-05-13)
- G4PhysicalVolumeModel:: GetAttDefs: Small bug fix.
- G4TrajectoriesModel:
  o Added fEventID;
  o Added GetAttDefs and CreateCurrentAttValues for event ID.

28th September 2012  Gabriele Cosmo  (modeling-V09-05-12)
- Explicitly include units header in G4ArrowModel.cc.

25th September 2012  John Allison  (modeling-V09-05-11)
- G4ArrowModel.cc:
  o Added protection, limited width to length/50.

4th September 2012  John Allison  (modeling-V09-05-10)
- G4LogicalVolumeModel:
  o Added G4bool Validate(G4bool){return true;} - i.e., always valid.
  o Correct spelling of name.
- G4PhysicalVolumeModel.cc: Minor improvement to a message.

15th July 2012  John Allison  (modeling-V09-05-09)
- Introduced G4ArrowModel.
- G4AxesModel: Re-implemented (uses G4ArrowModel).

5th July 2012  Gabriele Cosmo  (modeling-V09-05-08)
- Explicitly use inclusion of headers for system of units and physical
  constants, in plan to remove implicit inclusion from globals.hh.

7th June 2012  John Allison  (modeling-V09-05-07)
- Shadow clean.

31st May 2012  John Allison  (modeling-V09-05-06)
- G4TrajectoryOriginVolumeFilter.cc:
  o Brought stray print statement under control of verbosity.
  o Fixes bug report 1310.

10th April 2012  John Allison  (modeling-V09-05-05)
- G4CallbackModel: It ws a bad idea to delete function in destructor
  (see 7th March).  OK to delete, but catastrophe when you try to use
  it a second time, for example, when model is replaced by same model.

4th April 2012  John Allison  (modeling-V09-05-04)
- Tagged.

30th March 2012  John Allison
- G4PhysicalVolumeModel.cc:
  o If top volume is a replica or a parameterised, only draw first one.

26th March 2012  John Allison
- G4VModel: Added Get/SetType. The sub-class should set its type,
  which could be the class name, or, in the case of G4CallBackModel,
  it could be the type of object it is coding.
- G4PhysicalVolumeModel: Added GetFullPVPath.

23rd March 2012  John Allison  (modeling-V09-05-03)
- G4AxesModel: Augmented global description to allow more than one
  set of axes to be added to scene if significantly different.

7th March 2012  John Allison  (modeling-V09-05-02)
- G4CallbackModel: Delete function in destructor.  (Good practice
  to delete all stuff created on the heap.)

3rd January 2012  John Allison  (modeling-V09-05-01)
- Tagged.

30th December 2011  John Allison
- G4PhysicalVolumeModel::Validate: Searches also in parallel worlds.

30th December 2011  John Allison  (modeling-V09-05-00)
- G4TrajectoriesModel::DescribeYourselfTo:
  o Used Begin/EndDraw to improve drawing speed.
  o Assumes all trajectories are drawn with the same transformation.
    If not, a fatal exception with be raised in G4VisManager::DrawT.

12th November 2011  John Allison
- G4AttributeFilterT<T>::AddInterval and AddValue:
  o Relaxed exception in case of already existing interval/value.
  o Changed from Fatal to JustWarning.
  o In that case, return with no action.

11th November 2011  John Allison  (modeling-V09-04-05)
- G4VTrajectoryModel.hh: Coverity fix.

30th October 2011  John Allison  (modeling-V09-04-04)
- G4ModelApplyCommandsT: Fixed compiler warning.
- G4PhysicalVolumeModel: Added flag to G4PhysicalVolumeNodeID: true if drawn.

27th September 2011  John Allison  (modeling-V09-04-03)
- G4PhysicalVolumeModel::Validate: Strengthen case for issuing warnings so
  that warning not issued in normal case.
- Added some files to svn::ignore.

25th September 2011  John Allison  (modeling-V09-04-02)
- G4PhysicalVolumeModel: Tidied

16th September 2011  John Allison
- Migrated to new G4Exception.

25th January 2011  John Allison  (modeling-V09-04-01)
- G4TrajectortDrawerUtils.cc:
  o Fixed unresolved reference.
  o Tidied.

27th December 2010  John Allison  (modeling-V09-04-00)
- Tagged.

11th December 2010  John Allison
- G4AttributeFilterT.hh, G4TrajectoryDrawByAttribute.cc:
  o Changed some exceptions from FatalError to JustWarnings.
- G4TrajectoryDrawerUtils.cc:
  o Rework TimesValidity.

14th November 2010  John Allison  (modeling-V09-03-05)
- G4TrajectoryDrawerUtils.cc:Fixed time-slicing problem.

5th November 2010  John Allison  (modeling-V09-03-04)
- G4PhysicalVolumeModel.cc: Fixed Coverity warning.

1st June 2010  John Allison  (modeling-V09-03-03)
- G4TrajectoryDrawByParticleID.cc: Set some defaults:
    Set("gamma", "green");
    Set("e-", "red");
    Set("e+", "blue");
    Set("pi+", "magenta");
    Set("pi-", "magenta");
    Set("proton", "cyan");
    Set("neutron", "yellow");

30th May 2010  John Allison  (modeling-V09-03-02)
- Added G4DigiModel and G4DigiFilterFactories.
- G4BoundingSphereScene, G4PhysicalVolumeMassScene,
  G4PhysicalVolumeSearchScene:
  o Added AddCompound(const G4VDigi&).

28th May 2010  John Allison  (modeling-V09-03-01)
- G4TrajectoryDrawByAttribute.cc, G4TrajectoryDrawByCharge.cc,
  G4TrajectoryDrawByOriginVolume.cc, G4TrajectoryDrawByParticleID.cc:
  o Fixed unused parameter 'i_mode' warning.

11th May 2010  John Allison  (modeling-V09-03-00)
- G4ModelingParameters, G4PhysicalVolumeModel:
  o Replace polyhedra with solids for sections and cutaways.
- G4TrajectoriesModel: Trap use of i_mode and print warning.
- G4VTrajectoryModel and derived classes G4TrajectoryDrawBy*:
  o Introduce Draw method *not* containing i_mode.
- G4TrajectoryDrawerUtils:
  o Remove default (0) for i_mode arguments.
  o Introduce functions without i_mode.
  o Comment out unused DrawLineAndPoints function.
  o Trap use of i_mode and print warning.

27th April 2010 Laurent Garnier
- G4trajectoryDrawerUtils :
  o Optimisation when drawing lines

4th November 2009  John Allison
- G4PSHitsModel:
  o Now intended as end-of-run model.
  o Picks up hits from G4ScoringManager instead of event.

22nd October 2009  John Allison  (modeling-V09-02-05 coworks greps-V09-02-02)
- Added G4PSHitsModel for gMocren driver.
- G4PhysicalVolumeModel.cc: Makes use of HepPolyhedronProcessor.

21st October 2009  John Allison  (modeling-V09-02-04 coworks greps-V09-02-02)
- G4BoundingSphereScene, G4PhysicalVolumeMassScene,
  G4PhysicalVolumeSearchScene:
  o Added empty AddCompound (const G4THitsMap<G4double>&) methods.

10th October 2009  John Allison  (modeling-V09-02-03)
- G4PhysicalVolumeModel: Added G4PhysicalVolumeModelTouchable.  Used in
  ComputeMaterial.  Effective for nested parameterisations.

29th September 2009  John Allison  (modeling-V09-02-02)
- G4PhysicalVolumeModel.cc: Added warning if logical volume not defined.

25th February 2009  John Allison  (modeling-V09-02-01 - needs greps-V09-02-01)
- G4ModelApplyCommandsT: Added visManager->NotifyHandlers() after
  application (Apply) of all commands.  Forces update of all viewers
  after a change of model, e.g., trajectory colour, point size, etc.

24th February 2009  John Allison  (modeling-V09-02-00 - needs greps-V09-02-00)
- Added setAux/StepPtsSizeType commands (candidates: "none world screen").
- Added unit to setAux/StepPtsSize for SizeType == world.

27th July 2008  John Allison  (modeling-V09-01-01)
- G4PhysicalVolumeSearchScene.cc: Cosmetic improvement to a message.

4th January 2008  John Allison  (modeling-V09-01-00)
- Adapted to new BeginPrimitives2D signature.

10th November 2007  John Allison  (modeling-V09-00-00)
- Minor improvement in warning message after change of geometry.

30th May 2007  John Allison  (modeling-V08-03-02)
- Removed warnedAboutIMode from G4TrajectoryDrawerUtils.hh.  It was
  used only in G4TrajectoryDrawerUtils.cc and gave warnings about
  being unused in other .cc files that inculded
  G4TrajectoryDrawerUtils.hh.  warnedAboutIMode is now a static in
  G4TrajectoryDrawerUtils.cc.

30th May 2007  John Allison  (modeling-V08-03-01)
- Fix for SUN.

22nd May 2007  John Allison  (modeling-V08-03-00)
- Simplified G4Atts for Physical Volume Path.

3rd April 2007  John Allison  (modeling-V08-02-02)
- G4PhysicalVolumeModel: Added full volume path information and
  transformed axes to G4Atts.

25th March 2007  John Allison  (modeling-V08-02-01)
- G4PhysicalVolumeModel: Added solid dump and volume transformation to G4Atts.

5th January 2007  John Allison  (modeling-V08-02-00 - needs greps-V08-02-00)
- G4PhysicalVolumeModel.cc: Bug fix:
  o Correct treatment of ForcedLineSegmentsPerCircle when clipping.

16th November 2006  John Allison  (modeling-V08-01-15)
- Added protection for parallel worlds (zero region pointer).

14th November 2006  John Allison  (modeling-V08-01-14)
- Merged modeling-V08-01-13-branch onto main branch.

8th November 2006  John Allison  (modeling-V08-01-13-00)
- On modeling-V08-01-13-branch.
- Added G4Event pointer to modeling parameters.
- G4TrajectoriesModel and G4HitsModel: use the above (G4VSceneHandler
  supplies).

5th November 2006  John Allison  (modeling-V08-01-13)
- Further, hopefully, complete, protection against zero materials pointer.

3rd November 2006  John Allison  (modeling-V08-01-12)
- G4PhysicalVolumeModel.cc: Protected against zero material pointer.

3rd November 2006  John Allison  (modeling-V08-01-11)
- G4Trajectories/HitsModel.cc: Protected against zero pointers from
  collections.

2nd November 2006  John Allison  (modeling-V08-01-10)
- G4HitsModel: Added GetCurrentHit.

1st November 2006  John Allison  (modeling-V08-01-09)
- G4VModel: Removed warning messages from the virtual functions
  GetCurrentDescription and GetCurrentTag so that there is no longer
  a message if the concrete class does not implement.  The implementation
  in G4VModel, which is used by default, is simply to return the global
  description and tag.
- Removed GetCurrentDescription and GetCurrentTag from models for which the
  concept of "current" makes no sense or is not used:
    G4AxesModel, G4HitsModel, G4LogicalVolumeModel, G4ScaleModel, G4TextModel.
- G4ModelCommandsT: Minor corrections to guidance.

26th October 2006  John Allison  (modeling-V08-01-08)
- G4PhysicalVolumeModel: Changed CreateAttValues to CreateCurrentAttValues.
- G4TrajectoriesModel: Added GetCurrentTrajectory.

------------------------------------------------------
19th September 2006  John Allison  (modeling-V08-01-07)
- G4ModelingParameters: Added ExplodeCentre
- G4PhysicalVolumeModel.cc: Programmed ExplodeCentre.

17th September 2006 Jane Tinslay
- Shift an assert from G4AttributeFilterT to G4AttFilterUtils - was
  causing problems with XCode 2.0

------------------------------------------------------
15th September 2006  John Allison  (modeling-V08-01-06)
- G4PhysicalVolumeModel.ccChanged "Bookkeeping" to "Physics

14th September 2006 Jane Tinslay
- Fixes for sun

13th September 2006  John Allison
- G4ModelingParameters: Improved setting and access to explode factor.
- G4PhysicalVolumeModel.cc:
  o Implemented explode factor(radial move) feature for top level drawn
    volumes.
- G4TrajectoriesModel.cc: Improved debug checking and printing of G4Atts.
- G4ModelCommandUtils.hh, G4ModelCommandsT.hh:
  o  Re-instate setTimeSliceInterval command.

12th September 2006 Jane Tinslay
- Add attribute based trajectory drawing & filtering, and attribute based
  hit filtering

---------------------------------------------------
27th August 2006  John Allison  (modeling-V08-01-05)
- G4ModelingParameters: Added warning flag and section/cutaway polyhedron.
- G4PhysicalVolumeModel:
  o Acts on warning flag from G4ModelingParameters.
  o Added enum ClippingMode {subtraction, intersection};
  o Equipped for generic sectioning (DCUT) and cutaways.
- G4TrajectoryDrawerUtils::DrawWithTime:
  o Made use of G4VisAttributes time range.
  o Tidied.

26th August 2006  John Allison  (modeling-V08-01-04 - requires greps-V08-01-03)
- G4TrajectoryDrawerUtils.cc: Fixed compilation warning.

25th August 2006 Jane Tinslay
- Follow G4VFilter const change (requires greps-V08-01-03).

16th August 2006  John Allison  (modeling-V08-01-03)
- G4TrajectoryDrawerUtils.cc: Improved robustness of time slicing.
- G4ModelCommandsT.hh: In class G4ModelCmdSetTimeSliceInterval:
  cmd->SetUnitCategory("Time").
- G4TrajectoriesModel.cc: Improved debug statement.

14th August 2006  John Allison  (modeling-V08-01-02)
- G4ModelApplyCommandsT.hh: Added G4ModelCmdApplyDoubleAndUnit.
- G4ModelCommandsT.hh: Added G4ModelCmdSetTimeSliceInterval.
- G4VisTrajContext: Added TimeSliceInterval.
- G4TrajectoryModelFactories: Instantiated G4ModelCmdSetTimeSliceInterval.
- G4TrajectoryDrawerUtils.cc: Added time slicing.

10th July 2006  John Allison  (modeling-V08-01-01)
- Co-works with greps-V08-01-01.
- G4VModel: Removed GetG4PhysicalVolumeModel.
- G4ModelingParameters:
  o Removed RepStyle, ViewGeom, ViewHits and ViewDigis (not used).
  o Reduced number of constructors.
- G4PhysicalVolumeModel:
  o Removed Establish/DecommissionSpecials to conform with greps-V08-01-01.
  o Rationalised G4Atts: Added GetAttDefs/CreateAttValues.

3rd July 2006  John Allison  (modeling-V08-01-00)
- Needs greps-V08-01-00.
- G4PhysicalVolumeModel::G4PhysicalVolumeNodeID: Added GetNonCulledDepth.
- G4PhysicalVolumeModel.cc: Also added G4Atts for solids.
- G4TrajectoriesModel.cc: Added debug code.

7th June 2006  John Allison (modeling-V08-00-14)
- G4PhysicalVolumeModel.cc: Added protection for zero vis atts.

6th June 2006  John Allison (modeling-V08-00-13)
- G4TrajectoryChargeFilter.cc: Added #include <sstream> for Sun compiler.
- G4PhysicalVolumeModel::Validate: Relaxed requirement for modeling parameters.
  (Caused crash after change of geometry.)

2nd June 2006 Joseph Perl (modeling-V08-00-12)
- G4VisTrajContext: change default of point sizes from 0 to 2

30th May 2006 Jane Tinslay
- Add G4TrajectoryChargeFilter and G4TrajectoryOriginVolumeFilter

25th May 2006  John Allison  (modeling-V08-00-11)
- G4VModelFactory.hh: Indent printing of models.
- G4ModelApplyCommandsT.hh: Fix trivial compiler warnings.

22nd May 2006  John Allison  (modeling-V08-00-10)
- Remove dependency on Run.
- G4ModelingParameters.cc: Protect operator<< for zero fpDefaultVisAttributes.

12th May 2006  John Allison  (modeling-V08-00-09)
- G4TrajectoriesModel and G4HitsModel: Removed dependency on G4RunManager.
  Uses G4RunManagerKernel.  Needs event-V08-00-01.
- G4CallbackModel: Added G4VGraphicsScene argument to operator().

4th May 2006  Joseph Perl  (modeling-V08-00-08)
- Add missing assert to G4VTrajectoryModel needed by Windows.

4th May 2006  John Allison
- Improved protection for null models and parameters.

2nd May 2006 Jane Tinslay
- Add context to trajectory drawers. Intended to replace imode.
  Allows to configure default drawing style for lines, step and
  auxiliary points. For example, colours, visibility, point sizes,
  fill styles..
- Add generic drawer, G4TrajectoryGenericDrawer. Draws all trajectories
  in the same style, based on its default context.
- Update generic commands
- Add verbose to drawers

21st April 2006 Jane Tinslay  (modeling-V08-00-07)
- Get rid of some warning messages from G4ModelCommandsT
  when compiling on Linux
- Add Print method to G4VModelFactory

19th April 2006  John Allison  (modeling-V08-00-06 - needs greps-V08-00-02)
- G4BoundingSphereScene.hh, G4PhysicalVolumeMassScene.hh and
  G4PhysicalVolumeSearchScene.hh;  Added dummy Begin/EndPrimitives2D
  for greps-V08-00-02.
- G4PhysicalVolumeModel.cc: Improved legibility and efficiency of
  culling algorithm.

28th March 2006 Jane Tinslay (jst28032006)
- Add G4TrajectoryFilterFactories and G4TrajectoryParticleFilter
  for trajectory filtering.
- Add more generic commands to G4ModelCommandsT

28th March 2006  John Allison (modeling-V08-00-05)
- G4PhysicalVolumeMassScene and G4PhysicalVolumeSearchScene:
  o Removed EstablishSpecials.
- G4PhysicalVolumeModel:
  o GetTopPhysicalVolume, GetCurrentPV, GetCurrentLV,
    GetCurrentMaterial: return non-const pointers.  (It has proved
    impossibly difficult to deal with const pointers.)
  o Modified for new G4PhysicalVolumeSearchScene constructor.
- G4BoundingSphereScene: Removed use of GetG4PhysicalVolumeModel (uses
  dynamic cast instead).

24th March 2006 Jane Tinslay (jst24032006)
- Add G4bool visibility parameter to trajectory draw
  models "Draw" method.

16th March 2006 Jane Tinslay (jst16032006)
- Template commands and colour map used in trajectory models
- Introduce G4TrajectoryDrawByOriginVolume

14th March 2006  John Allison (modeling-V08-00-04)
- G4PhysicalVolumeModel::G4PhysicalVolumeNodeID: Added output operator<<.

16th February 2006  John Allison (modeling-V08-00-03)
- G4PhysicalVolumeModel: Minor enhancements to facilitate future
  removal of Establish/DecommisionSpecials.

8th February 2006  John Allison (modeling-V08-00-02)
- Added DrawingStyle to G4ModelingParameters.
- G4PhysicalVolumeModel: Fixed bug in culling of covered daughters and
  improved readability of culling algorithm.

26th January 2006  John Allison (modeling-V08-00-01)
- G4PhysicalVolumeModel: Added capability of maintaining path of the
  current drawn (non-culled) volume in terms of drawn (non-culled)
  ancestors.  See G4PhysicalVolumeModel.hh for detailed description.
- Removed some unnecessary data members and other small tidying.

11th January 2006  John Allison (modeling-V08-00-00)
- G4NullModel.cc: Changed G4Transform3D::Identity to G4Transform3D().

2nd December 2005  Joseph Perl (modeling-V07-01-07)
- Change "G4String inline" to "inline G4String" to correct compiler
  warning in G4VTrajectoryModel.hh.

30th November 2005  Gabriele Cosmo (modeling-V07-01-06)
- Trivial fix to G4VModel for support of CLHEP-2.0.X series.

28th November 2005  Jane Tinslay
- Remove names of unused parameters to stop compiler warnings

24th November 2005  John Allison (modeling-V07-01-05)
- Set initial values for originalRMin, originalRMax to satisfy compiler

23rd November 2005  Joseph Perl  (modeling-V07-01-04)
- Tagged in preparation for Geant4 8.0

23rd November 2005 Jane Tinslay
- Enhanced trajectory implementation

22nd November 2005  John Allison (modeling-V07-01-03)
- Implemented radial replicas for G4Tubs.
- Changed G4Transform3D::Identity to G4Transform3D().

24th October 2005  John Allison (modeling-V07-01-02)
- Added: G4VTrajectoryModel, G4VTrajectoryModelMaker, G4TrajectoryModelMaker
  and G4TrajectoryTestModel.
- G4VModel: cosmetic changes.

13th October 2005  John Allison (modeling-V07-01-01)
- Migrated to <sstream>.

13th September 2005  John Allison (modeling-V07-01-00)
- Fixed (non-)culling of transparent volumes.

7th June 2005  John Allison (modeling-V07-00-02)
- G4PhysicalVolumeModel: fixed case of off-origin volume.
- G4TextModel: Further small improvement.

31st May 2005  John Allison  (modeling-V07-00-01)
- G4TextModel: Improved global tag for better identification.

6th May 2005  John Allison  (modeling-V07-00-00)
- G4PhysicalVolumeModel: SetCopyNo of replicas and paramaterised volumes.

3rd March 2005  John Allison  (vis-V07-00-08)
- Added Set methods to G4VModel.
- Added argument to G4CallbackModel::operator()(const G4Transform3D&) so that
  the model could implement a given transformation.  Provided default for
  G4VUserVisAction::(const G4Transform3D& = G4Transform3D::Identity).

11th November 2004  John Allison  (vis-V06-02-05)
- Made use use of smart method GetPolyhedron for solids.  This greatly
  speeds 2nd and subsequent drawings when kernel access is required.

22nd September 2004  John Allison  (modeling-V06-02-01)
- Changed use of deprecated G4VPhysicalVolume::GetRotation to GetRotationValue.
- Fixed memory leak in G4PhysicalVolumeMassScene.

13th September 2004  John Allison  (modeling-V06-02-00)
- Added G4PhysicalVolumeMassScene.  From the header file:
// Calculates the mass of a geometry tree taking into account daughters
// up to the depth specified in the G4PhysicalVolumeModel.  Culling is
// ignored so that all volumes are seen.
//
// The calculation is quite tricky, since it involves subtracting the
// mass of that part of the mother that is occupied by each daughter and
// then adding the mass of the daughter, and so on down the heirarchy.
//
// Usage for a given G4PhysicalVolumeModel* pvModel:
//   G4PhysicalVolumeMassScene massScene;
//   massScene.EstablishSpecials (*pvModel);
//   pvModel->DescribeYourselfTo (massScene);
//   G4double volume = massScene.GetVolume();
//   G4double mass = massScene.GetMass();
//   massScene.Reset();
// See, for example, G4ASCIITreeSceneHandler::EndModeling().
- Added some access functions to G4PhysicalVolumeModel:
    GetTopPhysicalVolume, GetRequestedDepth, SetRequestedDepth.
- Protected GetPhysicalVolumeModel when all volumes "invisible".

12th November 2003  John Allison  (modeling-V05-02-02)
- CalculateExtent always searches complete hierarchy.

6th November 2003  John Allison  (modeling-V05-02-01, vis-V05-02-03)
- GNUmakefile: rationalised.

3rd November 2003  Gabriele Cosmo  (modeling-V05-02-00, vis-V05-02-02)
- Added inclusion of G4VSolid.hh in G4LogicalVolumeModel.cc to make it self
  consistent after header review in geometry category.

4th October 2003  Gabriele Cosmo  (vis-V05-02-01)
- GNUmakefile:
  o added dependency to new module "geometry/navigation".
  o replaced "digits+hits" with "digits_hits".
- Coworks with "geometry-V05-02-00" and "digits_hits-V05-02-00".

22nd September 2003  John Allison  (vis-V05-02-00, greps-V05-02-00)
- Removed a redundant comment.

20th November 2002  Gabriele Cosmo  (modeling-V04-01-00)
- Fixed access to static data (requires "greps-V04-01-04") in
  G4FlavoredParallelWorldModel.cc, to allow porting on Windows DLLs.

11th November 2002  John Allison  (modeling-V04-00-00)
- Added fDrawingMode data member to G4TrajectoriesModel.

24th October 2002  John Allison (vis-V04-01-03)
- Changes for AddThis(const G4VTrajectory&) and (const G4VHit&).

23rd February 2002  John Allison (vis-V04-00-02)
- Removed Begin/EndPrimitives from G4HitsModel and
  G4TrajectoriesModel.  This was causing nested calls to
  Begin/EndPrimitives (and thus to glNewList/EndList in OpenGL stored
  mode), since the trajectories and hits Draw methods themselves have
  Begin/EndPrimitives.

24th August 2001  John Allison  (vis-V03-02-13)
- Intoduced argument for printing in G4VModel::Validate(G4bool warn).
- Changed default return value in G4VModel::Validate(G4bool) to true.
- Invoke CalculateExtent after successful geometry change in
  G4PhysicalVolumeModel::Validate, and other bug fixes..

14th August 2001  John Allison  (vis-V03-02-11)
- Added sceneHandler.Begin/EndPrimitives messages to models (long
  standing bug!).

9th August 2001  John Allison  (vis-V03-02-10-00)
- Removed G4ModelingParameters::hierarchy.  It is no longer used.  The
  textual or graphical representation of the geometry hierarchy is now
  done in G4xxxTree classes in visua;ization/Tree.

25th July 2001  John Allison  (modeling-V03-02-03)
- Added G4VModel::GetG4PhysicalVolumeModel().
- Added G4VModel* argument to G4BoundingSphereScene constructor.
  Both the above are to facilitate access to a model, if it exists, and
  to invoke methods of G4PhysicalVolumeModel if it is one.
- Added code to curtail G4PhysicalVolumeModel search in G4BoundingSphereScene.

24th July 2001  John Allison  (modeling-V03-02-02)
- Added G4VModel::SetExtent(const G4VisExtent&).
- Cosmetic improvements to G4BoundingSphereScene.
- Augmented G4ScaleModel::fGlobalTag.

21st July 2001  John Allison  (modeling-V03-02-01)
- Added G4ScaleModel.
- Fixed bug in G4BoundingSphereScene::::Accrue().
- Also a few cosmetic changes.

18th July 2001  John Allison  (modeling-V03-02-00)
- Ensured rotation and translation of replica is restored.

3rd February 2001  John Allison  (vis-V03-00-02)
- Tidied for CodeWizard.

29th May 2000  John Allison
- Moved code for maintaining depth, physical and logical volume
  pointers from VisitGeometryAndGetVisReps to DescribeAndDescend to
  handle daughters of replicas correctly (Guy Barrand).

22nd May 2000  John Allison  (modeling-V01-01-00)
- Added G4VTreeGraphicsScene (DTREE).
- Commented out pVPV->SetCopyNo(n) on Makoto's advice in
  G4PhysicalVolumeModel.cc.

vis-V01-01-01  12th April 2000  John Allison
- Made G4PhysicalVolumeModel::DescribeSolid virtual.
- G4PhysicalVolumeModel::DescribeSolid no longer deals with composite
  solids - now programmed into CompositeSolid::CreatePolyhedron, where
  CompositeSolid means G4IntersectionSolid, G4SubtractionSolid and
  G4UnionSolid.
- G4PhysicalVolumeModel::DescribeSolid no longer deals with displaced
  solids - now programmed into G4DisplacedSolid::CreatePolyhedron.
- Added G4LogicalVolumeModel::DescribeSolid, which explicitly adds
  components of composite solids as white forced-wireframe objects.

vis-V00-01-10  25th November 1999  John Allison
- Adapted header files of modeling for Software Reference Manual.

vis-01-00-05  7th February 1999  John Allison

vis-01-00-05  7th February 1999  John Allison
- Added list facility to G4PhysicalVolumeSearchScene.
- Added virtual functions AddThis (const G4Polycone and G4Polyhedra to
  G4BoundingSphereScene and G4PhysicalVolumeSearchScene.

vis-00-04-01  25th November 1998  John Allison.
- Added const G4VisAttributes* fpDefaultVisAttributes and access
  functions to G4ModelingParameters.
- Reverted to default assignment operator and copy constructor for
  G4ModelingParameters.
- G4PhysicalVolumeModel can now handle invisible daughters.

31st August 1998  John Allison
- Added G4VModel::Validate() and in subclasses.

vis-00-02-05  27th August 1998  John Allison
- Added G4HitsModel and G4TrajectoriesModel.

vis-00-02-04  22nd August 1998  John Allison
- Made G4Transform3D fTransform a member of G4VModel (instead of pointer).
- Reversed order of parameters in G4VModel constructor.
- Much bug fixing.

vis-00-06-06  11th June 1998  John Allison
- G4PhysicalVolumeModel handles parametrised solids and materials.

vis-00-06-04  10th June 1998  John Allison
- Moved G4BoundingSphereScene from management to modeling.
- Added G4Transform3D data member.

modeling-00-04-01  4th March 1998  John Allison
- Last tag before moving to visualization.
- Removed G4ModelingParameters:: from G4ModelingParameters.hh constructor.

27th January 1998  John Allison
- New (temporay?) category.
- Incorporates modeling code which was in G4VScene.
