# Category opengl 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!

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

## 2024-09-13 John Allison (opengl-V11-02-09)
- G4OpenGLStoredQtSceneHandler.cc:
  - G4OpenGLStoredQtSceneHandler::ClearStore():
    -  Commented out some code related to the old scene tree. The old scene
       tree is currently (partially) disabled, but this code somehow affects
       the view in rare cases, e.g., after twinkling the volume does not return
       to its original colour. So I have disabled this, pending a review of
       the old scene tree. 

## 2024-10-25 John Allison (opengl-V11-02-08)
- G4OpenGLQtViewer.cc:
  - G4OpenGLQtViewer::currentTabActivated(): Fix compilation error, see Bug Report 2633.
    - Use .data().

## 2024-09-13 John Allison (opengl-V11-02-07)
- G4OpenGLQtViewer.cc:
  - Comment out code that refers to the old scene tree because it adversely impacts
    the new scene tree.
    - I would like to extract the old scene tree code completely, but so far I have
      found it difficult, since it is so entangled with other code. So my efforts so
      far have been to bop problems on the head as they arise. Not satisfactory, I
      know, and I will continue to work on it.

## 2024-08-13 John Allison (opengl-V11-02-06)
- G4OpenGLQtViewer:
  - Resolve the timing issues around switching to the vis sub-thread with the
    use of G4CONDITIONWAITLAMBDA.
  - Fix small memory leak in G4OpenGLQtViewer::DrawText.

## 2024-07-24 Guy Barrand (opengl-V11-02-05)
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer::ShowView: Qt6: do a:
    ((QApplication*)G4Qt::getInstance ())->processEvents();
  so that a:
    /vis/viewer/interpolate viewfiles/movie-1
  produces truly an animation.

## 2024-07-12 Guy Barrand (opengl-V11-02-04)
- G4OpenGLQtViewer: Qt6: implement ReadyToDraw(). It permits to avoid a crash in case
  of /run/beamOn in vis.mac at startup (especially on macOS).
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer: Qt5: in Initialise(), displace
  makeCurrent() after CreateMainWindow(). It avoids a crash in case of /run/beamOn
  in vis.mac at startup.
- G4OpenGLQtViewer: Qt5, Qt6: in DoneWithVisSubThread(), SwitchToMasterThread() protect
  against a possible null qGLW->context(). It permits to avoid a crash in case of
  doing /run/beamOn in vis.mac at startup.
- G4OpenGLQtViewer, G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer: Qt6:
  remove unused fields: fHasToRepaint, fUpdateGLLock, fQGLWidgetInitialiseCompleted
  and fPaintEventLock.
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer: Qt6: remove no more needed
  initializeGL() and showEvent() methods.
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer: Qt6: displace setExportImageFormat("jpg")
  in Initialise().

## 2024-06-21 Ben Morgan (opengl-V11-02-03)
- Use runtime checks for MT mode where possible.

## 2024-05-30 Guy Barrand (opengl-V11-02-02)
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer: Qt6: remove the usage of a paintEvent(),
  the paintGL() should be sufficient. Having an extra paintEvent() is confusing.
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer: Qt6: updateQWidget: use update() to trigger
  a repaint. It is what is documented.
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer: Qt6: Initialise(): do a:
    if(G4QGLWidgetType::isValid())
  before the glDrawBuffer(GL_BACK). It avoids a crash at startup on macOS.
  Do the same on the ClearView(), SetView().
- G4OpenGLViewer: have ClearView(), SetView(), ResetView() virtual so that we can do a
    if(G4QGLWidgetType::isValid())
  in viewers ClearView(), SetView().
- G4OpenGLQtViewer: updatePickInfosWidget, G4MouseReleaseEvent: Qt6: have a "makeCurrent,ResizeGL".
  G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer: Qt6: DrawView(): have a:
    if(IsGettingPickInfos()) {
      paintGL();
      return;
    }
  These modifications permit to restore picking. The today code has some "glGetIntegerv(GL_VIEWPORT)"
  done "out of makeCurrent()" that returns now, with Qt6::QOpenGLWidget, bad sizes. The
  "makeCurrent(), ResizeGL" restores good values, and the upper modifications in DrawView() enforces
  a paintGL() within the "makeCurrent()". Picking looks ok with these modifications.
- G4OpenGLQtViewer: G4OpenGLStoredQtViewer: Qt6: have ResizeWindow using glWidget->devicePixelRatio().
  To have good size handling on macOS (it looks ok to have this on Linux and Windows, then no need
  to "#ifdef __APPLE__").
- G4OpenGLQtViewer: Qt6: DrawText(): we implemented a "2D draw text" (with code found on stackoverflow)
  since the renderText() method is no more here on the new Qt6 QOpenGLWidget.

## 2024-05-13 Guy Barrand (opengl-V11-02-01)
- G4OpenGLQtViewer: MT: have the variables mWaitForVisSubThreadQtOpenGLContextMoved,
  mWaitForVisSubThreadQtOpenGLContextInitialized,
  c1_VisSubThreadQtOpenGLContextInitialized, c2_VisSubThreadQtOpenGLContextMoved local
  to the G4OpenGLQtViewer class. It avoids dead-locks in case of multiple OGLI, OGLS viewers
  if doing a "/run/beamOn" in each of them.

## 2024-01-11 Ben Morgan (opengl-V11-02-00)
- Make headers of implementation detail classes private.

## 2023-09-05 Ben Morgan (opengl-V11-01-13)
- Set AUTOMOC property on module when Qt used.

## 2023-08-14 John Allison (opengl-V11-01-12)
- G4OpenGLQt, G4OpenGLXm:
  - Simplify IsUISessionCompatible.
    - Exploit new method, G4UImanager::GetBaseSession (intercoms-V11-01-07).

## 2023-07-03 Ben Morgan (opengl-V11-01-11)
- Address Coverity reports 56371, 60839

## 2023-07-01 John Allison (opengl-V11-01-10)
- Fix precision-loss warning.

## 2023-05-31 Ben Morgan (opengl-V11-01-09)
- Remove support for Qt < 5.9
  - Clarify remaining version checks using QT_VERSION_CHECK instead of raw hex
- Add inclusion of qdesktopwidget header required by Qt < 5.10

## 2023-05-16 John Allison (opengl-V11-01-08)
- G4OpenGLQtViewer: Disable the "old" scene tree.
  - Comment out just two lines:
    - Prevent G4OpenGLQtViewer overwriting the "new" scene tree.
    - Prevent G4OpenGLQtViewer registering the "old" widget.
  - The problem is G4OpenGLQtViewer removes the "new" scene tree and
    registers the "old" one, not just for the OGLSQt viewer,
    but for *all* subsequent viewers, so using OGLSQt completely prevents
    use of the "new" scene tree. Geant4 examples execute
    "/vis/open OGL" in the "vis.mac" macro, so the "new" scene tree is
    never seen nor used. 
  - This is a "stop-gap" solution - we need to decide how to proceed.
    - We could keep the "old" scene tree as an option.
      - In favour of this: the "old" tree is more highly featured.
    - We could remove the "old" scene tree completely.
      - We should then transfer nice features of the "old" scene tree
        to the "new" one.
      - In any case, new features will be progressively added to the
        "new" scene tree in future developments.

## 2023-04-27 Ben Morgan (opengl-V11-01-07)
- Minimum build and code changes required to compile/link against both Qt5 and Qt6

## 2023-04-14 John Allison (opengl-V11-01-06)
- Co-working: visman-V11-01-04, greps-V11-01-03, interfaces-V11-01-11,
  openinventor-V11-01-04, vis_toolssg-V11-01-05.
- New Scene Tree Phase 2 - first implementation of a no-frills GUI-side
  - See visualization/management/History for full description.
- Revert earlier changes for the new scene tree.
  - After the introduction of virtual G4VInteractiveSession::UpdateSceneTree
    they are no loner necessary.

## 2023-04-02 Ben Morgan (opengl-V11-01-05)
- No longer link to QtPrintSupport, which is not used in the toolkit.
- Remove inclusion of qprinter.h.

## 2023-03-28 John Allison (opengl-V11-01-04)
- G4OpenGLQtViewer:
  - Move G4UIQt* fUiQt from private to protected.
  - Implement UpdateGUISceneTree.
    - fUiQt->UpdateSceneTree(fSceneTree).
- G4OpenGLImmediateQtViewer.cc:
  - Use UpdateGUISceneTree in DrawView.
- G4OpenGLStoredQtViewer.cc:
  - Use UpdateGUISceneTree if (kernelVisitWasNeeded).

## 2023-03-22 Ben Morgan (opengl-V11-01-03)
- Export public compile definitions to indicate availablity of specific drivers. Moves to
  "use on link" model.

## 2023-03-03 Ben Morgan (opengl-V11-01-02)
- Remove obsolete G4OPENGL_VERSION_2 symbol and G4OpenGLVboDrawer class.

## 2023-01-30 Ben Morgan (opengl-V11-01-01)
- Link to new G4UIcore/UIimplementation modules in place of former G4UIbasic/UIcommon

## 2023-01-28 Ben Morgan (opengl-V11-01-00)
- Make G4modeling a private dependency, unless Qt is active, when it must be public.

## 2022-11-25 Gabriele Cosmo (opengl-V11-00-21)
- Fixed compilation warnings for implicit type conversions on macOS/XCode 14.1.

## 2022-11-21 Ben Morgan (opengl-V11-00-20)
- Revert link support for Qt6 until code is ready.

## 2022-10-28 John Allison (opengl-V11-00-19)
- Update a comment about requesting a kernel visit when cutaway mode
  changes - noted but not relevant because OGL does its own cutaways:
  - G4OpenGLStoredQtViewer.cc
  - G4OpenGLStoredViewer.cc
- Minor tidy - speed cutaway check:
  - G4OpenGLViewer::SetView

## 2022-10-17 Gabriele Cosmo (opengl-V11-00-18)
- Replaced use of sprintf() with snprintf(), to fix deprecation compilation
  warnings on macOS-13 SDK.

## 2022-10-11 Ben Morgan (opengl-V11-00-17)
- Link to Qt OpenGLWidgets target for Qt6 only.

## 2022-10-07 Gabriele Cosmo (opengl-V11-00-16)
- Fixed compilation warnings on Intel/icc compiler for deprecated conversion
  of string literal to char* in G4OpenGLXmConvenienceRoutines and
  G4OpenGLXmViewer.

## 2022-09-14 John Allison (opengl-V11-00-15)
- G4OpenGLStoredViewer.cc, G4OpenGLStoredQtViewer.cc:
  - Add check on special mesh rendering option in CompareForKernelVisit.

## 2022-09-06 Ben Morgan (opengl-V11-00-14)
- Address dependency inconsistencies reported by geant4_module_check

## 2022-07-13 Ben Morgan (opengl-V11-00-13)
- Fix compiler warnings in the use of G4OpenGLQtViewer::toggleProjection.

## 2022-05-03 Ben Morgan (opengl-V11-00-12)
- Preliminary build support for Qt5 and Qt6

## 2022-05-03 Gabriele Cosmo (opengl-V11-00-11)
- Fixed GNUmakefile for missing compilation of `G4gl2ps`.

## 2022-04-27 John Allison (opengl-V11-00-10)
- Co-works with `visman-V11-00-15`.
- Move `G4gl2ps` from `management` to `OpenGL`.

## 2022-04-07 Guy Barrand (opengl-V11-00-09)
- Added missing dependency to G4tools in GNUmakefile...

## 2022-04-07 Guy Barrand (opengl-V11-00-08)
- Have G4OpenGLViewer use the thread safe tools/gl2ps.

## 2022-04-06 John Allison (opengl-V11-00-07)
- Use `StandardSpecialMeshRendering(mesh)`.

## 2022-03-24 John Allison (opengl-V11-00-06)
- Retire display list re-use and display list limit.

## 2022-03-22 Ben Morgan (opengl-V11-00-05)
- Use geant4_module_sources to add optional sources

## 2022-03-05 John Allison (opengl-V11-00-04)
- G4OpenGLSceneHandler::AddCompound(const G4Mesh& mesh):
  - For parameterised tetrahedron mesh, call default
    G4VSceneHandler::DrawTetMeshAsDots(mesh).
  - Tested on "ICRP145", a Geant4 application that we hope can become
    a Geant4 advanced example, downloaded from the supplementary material
    of Kim et al, ICRP, 2020. Adult mesh-type reference computational phantoms,
    ICRP Publication 145, Ann. ICRP 49(3).

## 2022-01-28 Ben Morgan (opengl-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.
- Make DLL export symbol a CMake module-level compile definition to aid
  future modularization

## 2021-12-16 John Allison (opengl-V11-00-02)
- G4OpenGLSceneHandler.cc:
  - AddCompound(const G4Mesh& mesh):
    - Use base class utility G4VSceneHandler::Draw3DRectMeshAsDots(mesh);

## 2021-12-11 John Allison (opengl-V11-00-01)
- G4OpenGLSceneHandler:
  - void AddCompound(const G4Mesh& mesh):
    - Add missing return statement for unimplemented cases.
    - Tidy.

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

---

# History entries prior to 11.0

12 November 2021 - Ben Morgan (opengl-V10-07-25)
- Retire G4VIS_... preprocessor symbols in toolkit build, only required
  by obsolete GNUmake system

8 November 2021 - Ben Morgan (opengl-V10-07-24)
- Retire G4UI/G4INTY_... preprocessor symbols in toolkit build, only required
  by obsolete GNUmake system

30 October 2021  John Allison  (opengl-V10-07-23)
- G4OpenGLStoredXmViewer destructor:
  No need to RemoveViewerFromList - this is done in the G4VViewer base class.

25 October 2021  Guy Barrand (opengl-V10-07-22)
- G4OpenGLImmediateSceneHandler.hh: idem as below.
- G4OpenGLStoredSceneHandler.hh: idem as below.
- G4OpenGLSceneHandler.hh: to quiet g++ about "AddPrimitive(G4Plotter&)", have:
    using G4VSceneHandler::AddPrimitive;

21 September 2021 Guilherme Amadio (opengl-V10-07-21)
- G4OpenGLViewer:
  o Fix C++20 warnings from GCC 11.2.0.

06 September 2021  John Allison  (opengl-V10-07-20)
- G4OpenGLImmediateQtViewer.cc and G4OpenGLStoredQtViewer.cc:
  o Set jpg as default export format for Qt viewers.
    . For use with /vis/ogl/export.
    . jpg is only available for Qt viewers - pdf is the default for
      other OpenGL viewers.
    . jpg is more faithful than pdf. For example, pdf, which uses gl2ps,
      is not good with transparency. Also gl2ps does not do text.
    . For complicated images - detectors of many tracks - gl2ps creates
      *huge* files. I have seen some 1000x bigger than the equivalent jpg.

01 August 2021  John Allison  (opengl-V10-07-19)
- G4OpenGLQtViewer::DrawText:
  o Fix text alignment issue with a fudge factor.
  o Specialise fudge factor for __APPLE__. It seems only Mac has this
    problem. Maybe it's to do with the retina display. Maybe Qt keeps
    it's own pixel size.

20 July 2021  John Allison  (opengl-V10-07-18)
- G4OpenGLViewerMessenger:
  o Remove /vis/ogl/printEPS.
  o This command is covered by the more versatile /vis/ogl/export.

19 July 2021  John Allison  (opengl-V10-07-17)
- G4OpenGLSceneHandler.cc:
  o Use C++17 [[fallthrough]] instead of // fallthrough in switch statements.

17 July 2021  John Allison  (opengl-V10-07-16)
- Rationalise image exporting in preparation for removing /vis/ogl/printEPS.
  o G4OpenGLViewer:
    . Subsume the code in printEPS into exportImage, thereby allowing
      the removal of the former function. exportImage is the "primary"
      function, called by the printEPS and export commands and callback
      functions. It calls printEPS, and is the only function to do so, so
      to rationalise and avoid confusion, move all the code to exportImage.
  o G4OpenGLXmViewer::print_callback:
    . Call exportImage instead of printEPS.

13 July 2021  John Allison  (opengl-V10-07-15)
- G4OpenGLStoredSceneHandler.cc, G4OpenGLViewerMessenger.cc:
  o Increase the default display list limit to 10 million.
  o The default OpenGL display list limit was 50,000, an archaic value
    from the days when memory was much more limited than is typical today.
    This MR increases the default value to 10 million, easily accommodated
    by modern RAM and GPU memory.
  o The number can be changed with /vis/ogl/displayListLimit, either to
    increase it further or lower it, subject to a lower limit of 10,000.

12 July 2021  John Allison  (opengl-V10-07-14)
- G4OpenGLImmediateXViewer::FinishView()
- G4OpenGLImmediateXmViewer::FinishView()
- G4OpenGLStoredXViewer::FinishView()
- G4OpenGLStoredXmViewer::FinishView()
- G4OpenGLXViewer::ShowView()
- G4OpenGLXmViewer::ShowView()
  o Comment out glXWaitGL().
    . Wait for effects of all previous OpenGL commands to be propagated
      before progressing.
    . Commented out July 2021 - slows rendering down in some cases and I
      don't see any adverse effects.

08 July 2021  John Allison  (opengl-V10-07-13)
- G4OpenGLSceneHandler.cc:
  o Disable (comment out) backface culling.
- G4OpenGLStoredViewer.cc and G4OpenGLStoredQtViewer.cc:
  o Suppress kernel visit (no longer needed) for cutaway drawing.
- Note 1: Section and Cutaway can reveal back-facing faces. If backface culling
  is implemented, the image can look strange because the back-facing faces are
  not there. As described above, we have disabled (commented out) backface
  culling. It seems not to affect performance - in fact, performance seems to
  improve it. Maybe the feature is archaic and modern GPUs are simply more
  efficient if backface culling is not requested.
- Note 2: In G4OpenGLStored(Qt)Viewer::CompareForKernelVisit we decide if a
  "kernel visit" (which involves a reconstruction of the graphical database
  from the Geant4 kernel) is required on a change of view parameters. Simple
  rotating and zooming does not require a kernel visit, but more sophisticated
  parameters may. In G4OpenGLSceneHandler we implement cutaways using
  OpenGL cut planes, so now we have disabled backface culling, we do NOT need
  to visit the kernel. This is the change that makes a huge speed up when
  a user requests cutaways.

05 July 2021  John Allison  (opengl-V10-07-12)
- G4OpenGLQtViewer:
  o Use modelShortName instead of modelDescription for TreeWidgetItem
    for nonPVmodel.

30 June 2021  John Allison  (opengl-V10-07-11)
- Requires greps-V10-07-09, modeling-V10-07-11 and visman-V10-07-11.
- Revise vis models. See visualization/modeling/History for more details.
- Consequent changes:
  o AddPrimitive(const G4Scale&) has been removed from all scene handlers.

29 June 2021  Gabriele Cosmo (opengl-V10-07-10)
- Fixed compilation error in G4OpenGLXmConvenienceRoutines when c++20 is enabled.

07 June 2021  John Allison  (opengl-V10-07-09)
- Requires greps-V10-07-07 (new method AddCompound (const G4Mesh&)).
- Requires modeling-V10-07-09 (new class G4Mesh).
- Requires visman-V10-07-10 (new default method and new commands).
- G4OpenGLSceneHandler:
  o Implement AddCompound (const G4Mesh&):
    Turns nested parameterisations into polymarkers of dots - much
    improved speed.
- G4OpenGLStoredViewer.cc and G4OpenGLStoredQtViewer.cc:
  o Force kernel visit if special mesh rendering parameters change.

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

15 April 2021  Guy Barrand (opengl-V10-07-07)
- G4OpenGLWin32Viewer: fixed occasional crash with G4UIWin32 when creating
  viewer from UI command: avoid indirect call to DrawView() while still within
  CreateMainWindow().

12 April 2021  John Allison (opengl-V10-07-06)
- Comment out makeCurrent in ~G4OpenGLImmediate/StoredQtViewer:
  o Prevents red-button crash.

29 March 2021  John Allison (opengl-V10-07-05)
- G4OpenGLQtViewer::addNonPVSceneTreeElement:
  Special case for markers - use Info() if non-empty for modelShortName,
  the name that appears in Qt's scene tree. This allows the user to design
  markers, e.g., a list of points, and give them a name that relates to the
  providence of the points, e.g., a particular material or geometry component.

11 March 2021  Gabriele Cosmo (opengl-V10-07-04)
- Enable extended WIN32 window in G4OpenGLWin32Viewer.
  Based on contribution by O.Pena-Rodrigues in GitHub PR#23.
- Removed [commented out] DrawView() implementation in G4OpenGLWin32Viewer.

09 March 2021  John Allison (opengl-V10-07-03)
- Removed Wt.
- G4OpenGLStoredQtViewer.cc:
  o Move fViewId<0 check to top of constructor to pick up errors in
    base class construction.

04 March 2021  Gabriele Cosmo (opengl-V10-07-02)
- Implemented WindowProc() function in G4OpenGLWin32Viewer for the Win32
  OpenGL driver (function that was commented out). It is now possible to
  change the Zoom and the orientation using the mouse (like in the Qt driver).
  Based on GitHub PR#20, contributed by Ovidio Pena Rodriguez.
- Added [commented out] DrawView() implementation in G4OpenGLWin32Viewer.

06 January 2021  John Allison (opengl-V10-07-01)
- Remove deprecated /vis/ogl/set/ commands. These have been deprecated
  since 2016. Since that time they have all printed a message, giving the
  new command. All examples have been checked for use of the deprecated
  commands, which have been replaced with the new ones. The commands
  involved are:
  o All commands connected with a time window. Use equivalent
    /vis/viewer/set/timeWindow commands.
  o "/vis/ogl/set/eventsDrawInterval <N> is replaced by
    "/vis/ogl/flushAt NthPrimitive <N>".

30 December 2020  John Allison (openGL-V10-07-00)
- G4OpenGLViewerMessenger: Remove deprecated /vis/ogl/set commands.
  o /vis/ogl/set/eventsDrawInterval: use /vis/ogl/flushAt
  o /vis/ogl/set/<time-interval-related-command>: use related
    /vis/viewer/set/timeWindow command.
  o All above commands have been deprecated (with a message) since 2017.

16 November 2020 Gabriele Cosmo (OpenGL-V10-06-13)
- Fixed typos in printed-out text. Addressing problem report #2285.

12 November 2020 Ben Morgan (OpenGL-V10-06-12)
- Apply typo fixes from Gurkan Myczko (https://github.com/Geant4/geant4/pull/15)

29 October 2020  Ben Morgan (OpenGL-V10-06-11)
- Remove inclusion of obsolete CMake module

20 October 2020  Jonathan Madsen (OpenGL-V10-06-10)
- Implemented G4RunManagerFactory::GetMasterRunManager()

18 September 2020  John Allison (OpenGL-V10-06-09)
- Part of vis-V10-06-07.
- G4OpenGLStoredViewer.cc and G4OpenGLStoredQtViewer.cc:
  o CompareForKernelVisit; Force kernel visit if global parameters change.
    . GlobalMarkerScale and GlobalLineWidthScale.
- G4OpenGLStoredViewer.cc, G4OpenGLStoredQtViewer.cc, G4OpenGLStoredXViewer.cc,
  G4OpenGLStoredXmViewer.cc, G4OpenGLStoredWin32Viewer.cc:
  o Move fLastVP=fVP so always updated (avoids unnecessary redraw at start)

28 August 2020 Ben Morgan (opengl-V10-06-08)
- Ensure use of XQuartz GL on macOS for X11/Xm, System GL
  for Qt. This can lead to both libraries linking, but there
  do not appear to be immediate issues with this.

19 June 2020  John Allison  (opengl-V10-06-07)
- Fix Qt 5.15 deprecation warnings.

1st June 2020. Ben Morgan (opengl-V10-06-06)
- Use CMake AUTOMOC to automatically generate and compile Moc
  sources

16th April 2020. Ben Morgan (opengl-V10-06-05)
- Remove Qt4 support

4th March 2020. John Allison  (opengl-V10-06-04)
- G4OpenGLViewer::setExportFilename:
  o Fix bug in /vis/ogl/export when dot in name.

13th February 2020. John Allison  (opengl-V10-06-03)
- G4OpenGLViewerMessenger: /vis/ogl/ commands:
  o Improved guidance.
  o Place in alphabetical order.
  o Tidy.

9th January 2020 Gabriele Cosmo (opengl-V10-06-02)
- Fixed deprecation warnings introduced with Qt-5.14.0 for use of
  QTime::start()/elapsed() in favour of respectives in QElapsedTimer,
  in G4OpenGLQtViewer.

13th December 2019 Ben Morgan (opengl-V10-06-01)
- Cleanup CMake build, removing obsolete granular library options and
  explicit include_directories.

12th December 2019 Ben Morgan (opengl-V10-06-00)
- Remove no longer required dependence on OpenGLU

28 November 2019 Gabriele Cosmo (opengl-V10-05-18)
- Fixed QT_VERSION protection for use of screening function in
  G4OpenGLQtViewer.

25 November 2019 Gabriele Cosmo (opengl-V10-05-17)
- Fixed deprecation compilation warning on Qt5 related to use of
  QProcess::setProcessChannelMode() in place of setReadChannelMode().

25 November 2019 Gabriele Cosmo (opengl-V10-05-16)
- Fixed protection for compilation on older versions of Qt, including Qt4.

21 November 2019 Laurent Garnier (opengl-V10-05-15)
- Remove Qt deprecation warnings
  * Replacing availableGeometry() by QGuiApplication::screenAt(QPoint(20,20))->availableGeometry()
  * Replace QProcess::setReadChannelMode() by setProcessChannelMode
  * Remove unused function hasPendingEvents()
  * Replace QFontMetrics::width()) by boundingRect(textCString[0]).width()

20 November 2019 Laurent Garnier (opengl-V10-05-14)
- Remove deprecated QSignalMapper class

19 november 2019 Laurent Garnier (opengl-V10-05-13)
- Refine DisplayListLimit command guidance and output

07 November 2019 Ben Morgan (opengl-V10-05-12)
- Only link to imported targets for Motif and X11
- Remove inclusion of QT_USE_FILE from CMake scripts.
  All usage is now through the qtX_ macros and imported targets
- Only use Wt through imported targets

04 November 2019  John Allison  (opengl-V10-05-11)
- Part of vis-V10-05-26.
- G4OpenGLSceneHandler::ScaledFlush:
  o Extend glFlush scaling to all circumstances (not just in the event loop).

22 October 2019  Gabriele Cosmo (opengl-V10-05-10)
- Rationalise headers inclusion in G4OpenGLQtViewer.cc.

11 Sept 2019  Laurent Garnier (opengl-V10-05-09)
- remove default font size and police

16 July 2019  John Allison (opengl-V10-05-08)
- Part of vis-V10-05-22.
- G4OpenGLImmediateXViewer:
  o Revert fix in OpenGL-V10-05-05. The fix in OpenGL-V10-05-07 is better.

06 July 2019  Guy Barrand (OpenGL-V10-05-07)
- Part of vis-V10-05-21.
- G4OpenGLXmViewer.cc:
  Fix argument compatibility in calls to XmVaCreateSimpleMenuBar and similar.
  Use (KeySym)XK_S instead of 'S', etc.
- G4OpenGLXViewer.cc:
  Improve logic for finding a colormap.

13 June 2019  John Allison (OpenGL-V10-05-06)
- Part of vis-V10-05-20.
- Final changes for introduction of cloud drawing:
  o Follow change of accessor name: GetNumberOfCloudPoints.

10 June 2019  John Allison (OpenGL-V10-05-05)
- Part of vis-V10-05-19.
- G4OpenGLImmediateXViewer:
  Force double buffer context. (This can happen anyway when the display
  list limit is reached in stored mode. Seems to be no problem.) We were
  finding that the single buffer visual gave an X Error (BadMatch) on
  some systems, so let us force the use if a double buffer. All systems
  have double buffers nowadays.
- G4OpenGLStoredViewer and StoredQtViewer:
  Force kernel visit on change of number of cloud points.

29 March 2019  John Allison (opengl-V10-05-04)
- G4OpenGLSceneHandler.cc: Fix Coverity warning. Minor tidying.
- G4OpenGLStoredViewer.cc and G4OpenGLStoredQtViewer.cc:
  In CompareForKernelVisit require kernel visit if section plane changes.
  Note this is required since *for now* sections are made in the base class
  by using Boolean Processor.

24 March 2019  John Allison (opengl-V10-05-03)
- Fix bug in /vis/viewer/set/sectionPlane.
  Involves using G4DisplacedSolid instead of plain G4VSolid.

18 March 2019  Gabriele Cosmo (opengl-V10-05-02)
- Corrected few typos in printout/comments.

10 March 2019  John Allison (opengl-V10-05-01)
- G4OpenGLStoredSceneHandler.cc: Tidy.

08 March 2019  John Allison (opengl-V10-05-00)
- G4OpenGLStoredSceneHandler.cc:
  o Avoid re-using display lists for markers. They may have their own
    position relative to the overall object transformation.

5 October 2018  John Allison (opengl-V10-04-10)
- In all header files, change
#ifdef G4VIS_BUILD_OPENGL_DRIVER
  to
#if defined (G4VIS_BUILD_OPENGL_DRIVER) || defined (G4VIS_USE_OPENGL)
  and similarly for OPENGLX, XM, QT, WT and WIN32. This is so that a user
  may include the OpenGL headers and use the OpenGL library. This will be
  useful if a user (or a developer) wishes to write a new vis driver
  based on the existing OpenGL code.

11 September 2018  John Allison (opengl-V10-04-09)
- G4OpenGLViewer: Fix shadowing of variable in namespace ‘CLHEP'.
  o Need #include <CLHEP/Units/SystemOfUnits.h> instead of
    #include "G4SystemOfUnits.hh". Then use, e.g., CLHEP::deg instead
    of deg.

12 August 2018  John Allison (opengl-V10-04-08)
- G4OpenGLStoredViewer::DrawDisplayLists:
  o Remove redundant calls to glColor.
  o Add G4VisAttributes for G4Circle lightFront(circleCentre);

11 August 2018  John Allison (opengl-V10-04-07)
- G4OpenGLStoredSceneHandler::AddPrimitivePreambleInternal
  o Disable GL_LIGHTING for 3D markers (It was already disabled for 2D.
    The problem was that 3D markers became dark with normal lighting.)

24 May 2018  John Allison (opengl-V10-04-06)
- G4OpenGLStoredQtSceneHandler.cc, G4OpenGLQtViewer.cc:
  o Fix gcc-8 warnings.
- G4OpenGLStoredSceneHandler.cc: Cosmetic.

25 April 2018  John Allison (opengl-V10-04-05)
- G4OpenGLStoredViewer::CompareForKernelVisit,
  G4OpenGLStoredQtViewer::CompareForKernelVisit:
  o Implement comparison for "colour by density".

24 April 2018  John Allison  (opengl-V10-04-04)
- Migrate to greps-V10-04-04.

13 February 2018 Jonathan Madsen (opengl-V10-04-03)
- Replaced explicit usage of G4Mutex locking/unlocking with
  G4AutoLock pointers initialized with std::defer_lock as this
  enables one to avoid any deadlock or non-locked condition_variable
  waits by using G4AutoLock::owns_mutex()

12 February 2018 Jonathan Madsen (opengl-V10-04-02)
- Updated G4CONDITIONWAIT(...) to new C++11 requirements
- Found probable bug in G4OpenGLQtViewer with condition wait -- not locked
  prior to entering condition, which is an undefined behavior. Adapted
  G4AutoLock to accept std::defer_lock_t (doesn't lock upon construction)
  to prevent deadlock that occurs when the mutex is locked

8th January 2017  John Allison  (opengl-V10-04-01)
- Merged timemovebranch:
  o Moved time window parameters from G4OpenGLStoredViewer to
    G4ViewParameters. Now one can interpolate time window parameters (using
    /vis/viewer/interpolate) and make a movie of particles moving through time.
  o See vis-V10-04-00 History for more details.

14th December 2017  John Allison  (opengl-V10-04-00)
- G4OpenGLStoredSceneHandler::AddPrimitivePreambleInternal:
  o Remove glDrawBuffer(GL_FRONT), which seems to cause problems
    for the case of display list memory being exceeded.

7th November 2017  John Allison  (opengl-V10-03-04)
- G4OpenGLViewer.cc, G4OpenGLQtViewer.cc:
  o Refine content of output of picking.

1st September 2017  Laurent Garnier (opengl-V10-03-03)
- Add patch affecting repaint for external applications. See bugzilla #1959.

23rd May 2017  John Allison (opengl-V10-03-02)
- Hopefully fix gcc-7.1 warnings.

16th May 2017  Laurent Garnier
- Fix DEV-262 bug. Picking was not working for retina display due to a screen factor *2

23rd April 2017  John Allison
- G4OpenGLXViewer.cc: Reverted to XA_RGB_BEST_MAP.
- G4OpenGLViewer.cc:
  o Minor improvement to picking (suppressing "no hits" message).
  o Minor code clean-uo.

18th January 2017  Laurent Garnier
- Merge John's picking branch
 o G4OpenGLViewer, G4OpenGLQtViewer, G4OpenGLSceneHandler, G4OpenGLStoredQtViewer, G4OpenGLViewer

G4OpenGLQtViewer.cc: Change labels of picking points in pick info box

17th January 2017  Laurent Garnier
- G4OpenGLQtViewer.cc: Change labels of picking points in pick info box

12th January 2017  John Allison (opengl-V10-03-01)
- G4OpenGLImmediate/StoredQtViewer::ShowView: Tidied.
- G4OpenGLSceneHandler::ScaledFlush: Tidied.

6th January 2017  John Allison (opengl-V10-03-00)
- G4OpenGLSceneHandler.cc: Fixed bug in ScaledFlush.

21th November 2016  Laurent Garnier (opengl-V10-02-26)
- Go back on the glCheckFramebufferStatus(): comment out this command

21th November 2016  Laurent Garnier (opengl-V10-02-25)
- Fix the glCheckFramebufferStatus() :
  o G4OpenGLViewer : Check only if Qt driver AND (NOT X + NOT XM + NOT WIN32)
  o G4OpenGLStoredQtViewer,G4OpenGLImmediateQtViewer :
    Remove unnecessary "#if GL_EXT_framebuffer_object"
- G4OpenGL.hh: Avoid the case where an XM and Qt OpenGL viewer came with both OpenGL from
  XM and Qt

20th November 2016  John Allison (opengl-V10-02-24)
- G4OpenGLStoredViewer.cc: Removed check on previous colour in
  DrawDisplayLists that was intended to avoid unnecessary calls
  to glColor but which in some circumstances prevented necessary
  calls.  Now glColor is called for all display lists, which is
  probably less demanding than checking in the first place.  Fixes
  the same problem as tag opengl-V10-02-22.

19th November 2016  Laurent Garnier (opengl-V10-02-23)
- G4OpenGLViewer.cc:  add isFramebufferReady() method
- G4OpenGLStoredViewer.cc/G4OpenGLViewer.hh/G4OpenGLImmediateQtViewer.cc/G4OpenGLStoredQtViewer.cc:
  o Fix the gray/white/black screen when launching a new viewer.
  o Fix DEV-176 and perhaps a few others

19th November 2016  Laurent Garnier (opengl-V10-02-22)
- G4OpenGLStoredViewer.cc :  Fis a color problem on transparent volumes (DEV-261)

17th November 2016  Laurent Garnier (opengl-V10-02-21)
- G4OpenGL.hh: Avoid the case where an X and Qt OpenGL viewer came with both OpenGL from
  X and Qt

4th November 2016  Laurent Garnier
- G4OpenGLQtViewer:
  o memory leak issue FIXED (very rare case)
- G4OpenGLViewerMessenger:
  o Fix a "variable never used" issue

4th November 2016  Laurent Garnier (opengl-V10-02-20 co-works with interfaces-V10-02-09)
- G4OpenGLQtViewer/G4OpenGLImmediateQtViewer/G4OpenGLStoredQtViewer:
 o Add a Qt signal/slot connection between the UI and QGLViewer. Allow us to better manage interaction between them
 o Remove (multiple) scene tree from a tab to put it in a single, auto-update widget
 o Remove (multiple) viewer properties from a tab to put it in a outside dialog
 o Remove (multiple) pick infos from a tab to put it in a outside dialog
 o Lot of remaning in order to do previous work
 o Fix a bad signal/slot connection for the filter of the scene tree (perhaps a bug in some cases)

23rd September 2016  John Allison (opengl-V10-02-19)
- G4OpenGLSceneHandler::ScaledFlush: Tidied.

21st September 2016  Gabriele Cosmo (opengl-V10-02-18)
- Fixed GNUMakefile for missing include dependencies...

21st September 2016  John Allison (opengl-V10-02-17)
- Fix warnings on Windows.

21st September 2016  John Allison (opengl-V10-02-16)
- Introduced /vis/ogl/flushAt.

19th September 2016  John Allison (opengl-V10-02-15)
- Needs modeling-V10-02-13 and visman-V10-02-27
- Adapted to the move of Vis Attributes Modifiers back to G4ModelingParameters.
- G4OpenGLQtViewer:
  o Added
  // Flag to indicate that action was initiated by interaction (mouse
  // click) on the scene tree.  It is used and reset in
  // G4OpenGLStoredQtViewer::CompareForKernelVisit to prevent rebuild
  // in this case.
  bool fMouseOnSceneTree;
- G4OpenGLStoredQtViewer::CompareForKernelVisit:
  o Added this to handle scene tree interaction better:
  // Don't check VisAttributesModifiers if this comparison has been
  // initiated by a mouse interaction on the scene tree.
  if (fMouseOnSceneTree) {
    // Reset the flag.
    fMouseOnSceneTree = false;
  } else {
    // Not initiated by a mouse so compare for kernel visit.
    if (lastVP.GetVisAttributesModifiers() !=
           fVP.GetVisAttributesModifiers()) {
      return true;
    }
  }

15th September 2016  John Allison (opengl-V10-02-14)
- G4OpenGLStoredQtViewer:
  o Re-instated G4OpenGLStoredQtViewer::CompareForKernelVisit:
    Now ignores changes in Vis Attributes modifiers (as before).
- G4OpenGLQtViewer:
  o Uses G4VViewer::TouchableSetVisibility and TouchableSetColour.

12th September 2016  John Allison (opengl-V10-02-13)
- G4OpenGLQtViewer.cc: Added calls to SetTouchable.

11th September 2016  John Allison (opengl-V10-02-12)
- GetColour/GetColor no longer takes an argument.
- Make sure applicable vis attributes are obtained.
  // Get and check applicable vis attributes.
  //   fpVisAttribs = fpViewer->GetApplicableVisAttributes(fpVisAttribs);
  // Note: the vis attributes may have been modified by the viewer.  See
  // code in G4VViewer::GetApplicableVisAttributes.

9th September 2016  John Allison (opengl-V10-02-11)
- Needs modeling-V10-02-11 and visman-V10-02-22.
- Moved Vis Attributes Modifiers (VAMs) from G4ModelingParameters
  to G4ViewParameters.

8th September 2016  John Allison
- G4OpenGLStoredQtViewer:
  o G4OpenGLStoredQtViewer::CompareForKernelVisit:
    . Now simply invokes G4OpenGLStoredViewer::CompareForKernelVisit.
  o Fix bug:
    if (kernelVisitWasNeeded) {  // was fNeedKernelVisit
      displaySceneTreeComponent();
    }

7th September 2016  John Allison
- Fixed visibility check.  Now correctly updates VAMs (Vis Attribute
  Modifiers) when user clicks on visibility buttons.
- G4OpenGLQtViewer.cc:
  o G4OpenGLQtViewer::setCheckComponent sets the VAMs.
  o G4OpenGLQtViewer::sceneTreeComponentSelected becomes empty.

31st August 2016  John Allison (opengl-V10-02-10)
- Fix G4Orb and G4Ellipsoid hiding warnings.

14th August 2016  John Allison (opengl-V10-02-09)
- G4OpenGLSceneHandler.cc and G4OpenGLViewer.cc:
  o Improved comments.

16th June 2016  John Allison  (opengl-V10-02-08)
- G4OpenGLViewer.cc: g4GluLookAt and g4GluPickMatrix:
  o Changed GLfloat to GLdouble.  Fixes a problem with projections
    of scenes with very large, e.g., galactic, size.

14th June 2016  John Allison  (opengl-V10-02-07)
- G4OpenGLXmWindowHandlingCallbacks.cc: Commented out some code in
  void G4OpenGLXmViewer::expose_callback (Widget w,
                                          XtPointer clientData,
                                          XtPointer)
{ ...
//??????????????????????????? This might be a problem in MT mode.
//  glXMakeCurrent (pView->dpy, XtWindow(pView->glxarea), pView->cxMaster);
//  pView->SetView ();
//  pView->ClearView ();
//  pView->DrawView ();
//???????????????????????????? Commented out 14/06/16  JA
}
  This was causing SetView to be called from the Xt loop from the vis
  thread in MT mode.  It didn't like that.  It does seem to be required,
  but keep it there, commented, for now.

7th June 2016  Laurent Garnier
- G4OpenGLQtViewer: Better quality movie generation (change parameters)

1st June 2016  Laurent Garnier
- G4OpenGLWin32Viewer :Fixed compilation warnings on Win32 about LONG_PTR

1st June 2016  John Allison  (opengl-V10-02-06)
- G4OpenGLXViewer.cc: Fixed bug in GetPickDetails (wrong placement
  of std::ostringstream oss;).

30th May 2016  John Allison  (opengl-V10-02-05)
- G4OpenGLXViewer.cc:
  o G4OpenGLXViewer::SetView: Added thread awareness regarding
    glXMakeCurrent.  NOTE: This will have to be done for Win32
    for multithreading on Windows.
- Tidying of outdated comments.

2nd May 2016  John Allison  (opengl-V10-02-04)
- G4OpenGLXmViewer.cc: Added glXWaitGL (); glFlush (); to ShowView
  to ensure all items get flushed to screen, even when
  eventsDrawInterval is set >1.
- G4OpenGLSceneHandler.hh: Made Get/SetEventsDrawInterval static
  to match static members changed in opengl-V10-02-03.

23rd April 2016  John Allison  (opengl-V10-02-03)
- /vis/ogl/set/eventsDrawInterval and /vis/ogl/set/displayListLimit:
  Fixed some inconsistencies.
  o G4OpenGLViewerMessenger.cc: eventsDrawInterval now applies also
    to immediate mode.
  o G4OpenGLSceneHandler.hh/cc: Made fEventsDrawInterval and
    fEventsWaitingToBeFlushed static so that they apply to all
    OGL scene handlers.
  o G4OpenGLImmediateSceneHandler.cc: Fixed bug in EndPrimitives2D -
    now calls ScaledFlush.
  o G4OpenGLStoredSceneHandler.cc: Simply moved static variable
    implementations to near top of file.

10th February 2016 Andrea Dotti (opengl-V10-02-00)
- Fix typo for macro G4CONDITIONBROADCAST (requires global-V10-02-03)

27th January 2016  John Allison
- CompareForKernelVisit:
  Tested for total vis attributes modifiers instead of just for size.

26th January 2016  John Allison
- G4OpenGLViewer::getRealPrintFilename:
  o fExportFilename contains filled characters:
    << setw(4) << setfill('0') << fExportFilenameIndex
    so that files can easily be referenced in alphanumeric order.

14th January 2016  John Allison
- Fix for notifying multiple OGL X views:
  o Added glXMakeCurrent(dpy,win,cxMaster) to G4OpenGLXViewer::SetView.

11th December 2015  Laurent Garnier
- G4OpenGLQtViewer: Add the "F" key to test flytrough
- G4OpenGLViewer: Fix a problem in picking, does not clean correctly
    an outupt stream buffer

5th November 2015  Laurent Garnier (opengl-V10-01-13)
- G4OpenGLViewer: Fix warning with VC14

5th November 2015  Laurent Garnier (opengl-V10-01-12)
- Fix the "SetVisible" problem on
  * Linux/Windows
  * Mac with Qt4 (or with Qt5)
  but introduce another minor problem: when opening a new viewer, we have to update it by clic
  into viewer, or issue "/vis/viewer/refresh"

2nd November 2015  Laurent Garnier
- G4OpenGLViewer.cc: Fix a small problem in picking list

21st September 2015  John Allison  (opengl-V10-01-11)
- G4OpenGLXViewer.cc: Uses <chrono> for picking.  (Another attempt.)

5th August 2015  John Allison  (opengl-V10-01-10)
- Reverted to G4THREADSLEEP for picking.

1st August 2015  John Allison  (opengl-V10-01-09)
- G4OpenGLXViewer.cc:
  o Uses <chrono> for picking.

30th July 2015  John Allison  (opengl-V10-01-08)
- Improved graphics system fallback strategy:
  o Implemented IsUISessionCompatible in G4OpenGLQt and G4OpenGLXm.
  o Qt not allowed unless a Qt session has been instantiated.
  o Interactive graphics systems (Qt, Xm) are not allowed in batch.
- G4OpenGLStoredQtSceneHandler.cc: Removed unused variable.

29th July 2015  Laurent Garnier
- Fix a minor problem for Qt driver: open/close icons on scene tree/viewer properties and pick were not good at start
- Minor improvements on the interface on scene tree/viewer properties and pick item menu

28th July 2015  Laurent Garnier
- Fix a bug when launching OGL driver from a macro file (in batch mode). Crash solved,
  but an exception is still sent

24th July 2015  Laurent Garnier
- Clean debug statements
- FIX DEV-86: extra ".eps" at the end of filename

26th June 2015  John Allison (opengl-V10-01-07)
- G4OpenGLStoredViewer: Coverity fix (uninitialised data member).
- G4OpenGLViewer.cc: Fixed bug found by Coverity (=! instead of !=).

3rd June 2015  John Allison (opengl-V10-01-06 co-works with visman-V10-01-10)
- Needs global-V10-01-13 for G4OpenGLXViewer.cc.
- Migrated to new G4VViewer interface - see visman-V10-01-10.
- G4OpenGLXViewer.cc: Re-introduced sleep while waiting for pick action.

27th May 2015  Laurent Garnier (opengl-V10-01-05 co-works with visman-V10-01-09)
- A bit of cleaning in managing OpenGL context (Qt)

26th May 2015  John Allison
- G4OpenGLXViewer.cc: Removed sleep in pick action for now.  Wait for globals.

26th May 2015  John Allison
- G4OpenGLXViewer.cc: Added sleep while waiting for pick action.

26th May 2015  Laurent Garnier
- Add methods to manage QtGLContext (not finished yet!)

19th December 2014  John Allison  (opengl-V10-01-04)
- Removed debug printing (MT mode).

16th December 2014  John Allison  (opengl-V10-01-03)
- G4OpenGLQtViewer.cc: Fixed compiler warning.
- Merged vis sub-thread developments.

15th December 2014  Laurent Garnier  (opengl-V10-01-02)
- G4OpenGLViewer.cc
  o replace "far" and "near" by "zFar" and "zNear" to avoid windows errors

15th December 2014  Laurent Garnier  (opengl-V10-01-01)
- Same tag as opengl-V10-01-00. Try to understand why on a window machine :
  "G4OpenGLViewer.cc(1445): error C2059: syntax error : ')' [D:\build\"

15th December 2014  Laurent Garnier  (opengl-V10-01-00)
- G4OpenGLViewer,
  G4OpenGLImmediateSceneHandler,
  G4OpenGLStoredSceneHandler,
  G4OpenGLStoredViewer,
  G4OpenGLViewer.cc :
  Fix a problem when zooming on small volumes. The glOrtho function has some problems with
  small values. Calculate all by hand and call glMatrix seems to solve this.

2nd December 2014  John Allison  (vis-MT-branch-00-opengl-12)
- G4OpenGLStoredQtViewer::DrawView(): Removed thread restriction.
- G4OpenGLQtViewer.cc:
  o Messy experimental version - needs cleaning.  I think this
    is not be necessary but leave it for now.
namespace  {
  const QGLContext* masterContext = 0;
  const QGLContext* visSubThreadContext = 0;
}

30th November 2014  John Allison  (vis-MT-branch-00-opengl-11)
- Introduced DoneWithMaster/VisSubThread.

26th November 2014  John Allison  (vis-MT-branch-00-opengl-10)
- Merged opengl-V10-00-28 into MT version.

25th November 2014  Laurent Garnier  (opengl-V10-00-28)
- G4OpenGLStoredQtViewer/G4OpenGLImmediatedQtViewer :
  Fix refresh problem due to a bad threading management

25th November 2014  John Allison
- G4OpenGLQtViewer.cc:
  o Fixes hidden marker field in Qt viewer properties.
- G4OpenGLStoredSceneHandler.cc:
  o Fixes a bug whereby hidden markers are not respected if 2D objects
    are drawn.

22nd November 2014  John Allison  (vis-MT-branch-00-opengl-09)
- Merged opengl-V10-00-27 into MT version.

21st November 2014  Laurent Garnier  (opengl-V10-00-27)
- G4OpenGLStoredQtViewer/G4OpenGLImmediatedQtViewer :
 o Avoid repainting problems by disable recursive repaints (from last commit)

20th November 2014  Laurent Garnier  (opengl-V10-00-26)
- G4OpenGLVboDrawer:
 o Fix a compilation issue with Wt driver
- G4OpenGLStoredQtViewer/G4OpenGLImmediatedQtViewer :
 o Avoid recursive repaints
- G4OpenGLQtViewer :
 o Fix some minor GUI visual issues

19th November 2014  Laurent Garnier  (opengl-V10-00-25)
- G4OpenGLQtViewer: Allow viewer properties/picking/scene tree to be accessible
  from an external application

18th November 2014  Laurent Garnier  (opengl-V10-00-24)
- G4OpenGLQtViewer: Fix JIRA DEV-173 about using external application

8th November 2014  John Allison  (vis-MT-branch-00-opengl-08)
- Merged trunk again.  (Just History.)

7th November 2014  John Allison  (vis-MT-branch-00-opengl-07)
- Merged trunk again.  (Some developments by Laurent.)

7th November 2014  John Allison  (vis-MT-branch-00-opengl-06)
- Merged trunk again.  (Some developments by Laurent.)

7th November 2014  John Allison  (vis-MT-branch-00-opengl-05)
- Merged the trunk into this branch, except:
  o Re-introduced updateQWidget() in G4OpenGLStoredQtViewer::ClearView.

7th November 2014  Laurent Garnier  (opengl-V10-00-22 - opengl-V10-00-23)
- G4OpenGLQtViewer:
 o Fix the "invalid drawable" warning in Qt
 o Set the scene tree / viewer properties / picking open at the beggining
 o Move "search" at the top of scene tree component
 o Fix a problem with Picking composant, it was impossible to disable it.
 o Add viewer properties and picking for Immediate mode
 o Fix a possible problem for fSceneHandler.GetScene()
 o Hide picking infos at the beggining
 o open all scene tree items
- G4OpenGLStoredQtViewer:
 o Remove ClearView() : Cause the ugly window problem

- G4OpenGLViewer:
 o Fix glCheckFramebufferStatus problem by #ifdef GL_VERSION_3

6th November 2014  Laurent Garnier
- G4OpenGLQtViewer :
 o Rename fWindow by fGLWidget and avoid problems for users using an
   external Qt Application (and external Main Window)
 o Remove resizing GLwidget *before* it was attached in the ui. This
   will prevent from a early repainting
 o Fix warnings
- G4OpenGLViewer :
  o Add ClearViewWithoutFlush() function
- G4OpenGLStoredQtViewer/G4OpenGLImmediateQtViewer :
  o Add a protection in case vis is called in another thread than main thread
- G4OpenGLStoredQtViewer:
  o Fix ugly window at beginning

G4OpenGLWtViewer
  o Fix a problem with Wt include names on case sensitive systems

7th November 2014  John Allison
- G4OpenGLQtViewer.cc: Fixed compiler warning.

6th November 2014  John Allison  (vis-MT-branch-00-opengl-03)
- G4OpenGLQtViewer.cc:
  o Fixed missing return value.
  o Added a comment for possible future attention.
- G4OpenGLXmWindowHandlingCallbacks.cc:
  o Added a comment for possible future attention.

5th November 2014  Laurent Garnier
- G4OpenGLQtViewer:
 o Rename fWindow by fGLWidget and avoid problems for users using an external
   Qt Application (and external Main Window)
 o Remove resizing GLwidget *before* it was attached in the ui. This will prevent
   from a early repainting

1st November 2014  John Allison  (vis-MT-branch-00-opengl-02)
- Fixed mistake in merging.

1st November 2014  John Allison  (vis-MT-branch-00-opengl-01)
- Merged vis-V10-00-11 and tagged.

5th November 2014  Laurent Garnier
- G4OpenGLQtViewer:
 o Rename fWindow by fGLWidget and avoid problems for users using an external
   Qt Application (and external Main Window)
 o Remove resizing GLwidget *before* it was attached in the ui. This will prevent
   from a early repainting

30th October 2014  Laurent Garnier (opengl-V10-00-21)
- Tagged

27th October 2014  Laurent Garnier
G4OpenGLStoredViewer
  o Solve DEV-170 bug, introduced 4th september
G4OpenGLQtViewer
  o Add SwitchToVisSubThread() and SwitchToMasterThread() functions

24th October 2014  Laurent Garnier (opengl-V10-00-20 require interfaces-V10-00-15)
G4OpenGLImmediateSceneHandler, G4OpenGLSceneHandler :
  o Improvements for OpenGL VBO
G4OpenGLQtViewer:
  o Suppress sizeX, sizeY when calling AddTabWidget (needs interfaces-V10-00-15)

31th October 2014  Laurent Garnier
  o Fix a problem with Wt include names on case sensitive systems

29th October 2014  Laurent Garnier
- G4OpenGLViewer :
  o Add a ClearView without flush function
- G4OpenGLStoreQtViewer :
  o Add a lock to prevent recursive updates
  o Implements ClearView in order to force a redraw (updateGL())

28th October 2014  Laurent Garnier
- G4OpenGLStoredQtViewer/G4OpenGLImmediateQtViewer  : Prevent from calling redrawing
  scene inside a Vis Thread

27th October 2014  Laurent Garnier
- G4OpenGLStoredViewer
  o Solve DEV-170 bug, introduced 4th september
- G4OpenGLQtViewer
  o Add SwitchToVisSubThread() and SwitchToMasterThread() functions

22nd October 2014  John Allison  (vis-MT-branch-00-opengl-00)
- Sub-thread developments.

24th October 2014  Laurent Garnier (opengl-V10-00-20 require interfaces-V10-00-15)
G4OpenGLImmediateSceneHandler, G4OpenGLSceneHandler :
  o Improvements for OpenGL VBO
G4OpenGLQtViewer:
  o Suppress sizeX, sizeY when calling AddTabWidget (needs interfaces-V10-00-15)

22nd October 2014  John Allison  (vis-MT-branch-00-opengl-00)
- Sub-thread developments.

22nd October 2014  John Allison  (opengl-V10-00-19)
- Tagged.

9th October 2014  Laurent Garnier
- G4OpenGL.hh :
  o Remove specific include for Wt
- G4OpenGLQtViewer, G4OpenGLStoredQtViewer, G4OpenGLImmediateQtViewer :
  o Rename fReadyToPaint to fQGLWidgetInitialiseCompleted
  o Rename fIsRepainting to fPaintEventLock
- G4OpenGLSceneHandler :
  o Change specific things from Wt viewers to all OpenGL2
- Rename G4OpenGLVBOViewer files to G4OpenGLVboDrawer
- G4OpenGLViewer
  o Move OpenGL2 specific things outside (in G4OpenGLVboDrawer)
  o Move Wt specific things now available for all OpenGL2
  o Avoid a warning from coverity in DrawText
- G4OpenGLImmediateQtViewer
  o Add some work about OpenGL2 (not yet finished)

10th September 2014  Laurent Garnier
- Renaming G4OpenGLWtDrawer => G4OpenGLVboDrawer  to be able to add Wt/Qt inside
- G4OpenGLImmediateWtViewer, G4OpenGLSceneHandler : Renaming + remove unuseful thing

10th September 2014  Laurent Garnier
- G4OpenGLWtDrawer, G4OpenGLViewer : Enhancements for OpenGL VBO

4th September 2014  Laurent Garnier
- G4OpenGLStoredViewer :
  o Remove unnecessary call to :
   glEnable (GL_DEPTH_TEST) and glDepthFunc (GL_LEQUAL)
   glColor4d()
- G4OpenGLStoredSceneHandler : Remove glDrawBuffer(GL_BACK)
- G4OpenGLStoredQtViewer : Optimizations
- G4OpenGLSceneHandler :
  o Remove unnecessary glEdgeFlag (GL_TRUE)
  o lineWidth(), markerSize()
  o Little work for Vertex Buffer Object
- G4OpenGLImmediateQtViewer : Avoid paintEvent() at initialisation

28th August 2014  Laurent Garnier
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer :
  o Rename to avoid confusion :
    - fIsRepainting -> fPaintEventLock : Could not have another paintEvent() inside
      a PaintEvent()
    - fReadyToPaint -> fQGLWidgetInitialiseCompleted : Wait for complete Initialization
      before drawing anything
  o Call ClearViewWithoutFlush() instead of ClearView() : Avoid a unnecessary flush()
- G4OpenGLQtViewer :
  o Do not trigger a resizeEvent before adding viewer to the MDIArea
  o FinishView() : Nothing to do (instead of a glFlush() )
- G4OpenGLStoredQtViewer :
  o Remove makeCurrent() at beginning of Initialie(), not useful
  o Remove setVisible() in InitializedGL() : do not set this component visible until
    it is totally realized
    (normally done by G4UIQt::AddTab() )
  o Remove sendPostedEvents () in InitializedGL() : Not useful and cause the mainWindow
    to be redraw before the session_start()
  o Remove makeCurrent() in ComputeView ()
  o Call ClearViewWithoutFlush() instead of ClearView() : Avoid a unnecessary flush()
  o In ResizeGL() : Now call the Clear-Set-Draw sequence
  o Move half of painGL() in paintEvent(). The paintGL() function now does only the
    Set-Clear-Compute sequence.
  o showEvent() does now only repaint visible windows
  o Remove glFlush() in DrawView(). Avoid flickering
- G4OpenGLViewer :
  o Add a new function ClearViewWithoutFlush(): Avoid a unnecessary flush()

22th August 2014  Laurent Garnier (opengl-V10-00-18)
- G4OpenGLQtViewer :
  o Fix a crash when closing a tab viewer when auto rotating
  o Change the "search" look and feel in the tree viewer

13th August 2014  Laurent Garnier (opengl-V10-00-17)
- G4OpenGLQtViewer : Fix a compiler warning

4rd August 2014  Laurent Garnier
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer, G4OpenGLQtViewer :
  o Add a keyReleaseEvent() method
  o Allow rotation/move during picking
- G4OpenGLQtViewer :
  o Change cursor shape according to mouse operation
  o Activate picking info widget when picking

3rd August 2014  Laurent Garnier (opengl-V10-00-16)
- G4OpenGLQtViewer : Fix a compilation error(missing change in G4OpenGLQtViewer.hh)

1st August 2014  Laurent Garnier (opengl-V10-00-15)
- G4OpenGLXViewer : Fix a compilation error

30th July 2014  Laurent Garnier (opengl-V10-00-14)
- G4OpenGLImmediateQtViewer/G4OpenGLStoredQtViewer :
  o Add the "event" parameter to "mouseReleaseEvent" method
- G4OpenGLQtViewer :
  o Move picking event from "mouse click" to "mouse release" function
  o Fix a compilation problem with std::to_string
- G4OpenGLViewer :
  o Fix a compilation problem with std::to_string

30th July 2014  Laurent Garnier (opengl-V10-00-13)
- G4OpenGLViewer : Fix a compilation error

30th July 2014  Laurent Garnier (opengl-V10-00-12)
- G4OpenGL.hh:
  o Remove all references to glu.h
- G4OpenGLXViewer :
  o Replace gluGetError to avoid calling of glu function

30th July 2014  Laurent Garnier
- G4OpenGLStoredSceneHandler : Change some G4cout in G4err in case of error messages

30th July 2014  Laurent Garnier
- G4OpenGLQtViewer :
  o Add a "picking info" component at bottom left inside the scene browser
  o Add a horizontal splitter inside the scene browser
  o Beginning of changing color of a picking item (need to be improved)
  o Some renaming on signalMapper parameters
  o Fix a bug : Previously when changing cursor to "Pick" on context menu, nothing was done.
  o Change picking effect, instead of displaying in G4Cout, will now display all picking infos
    separate by "hit number" in another widget inside the scene browser
  o New method "changeColorAndTransparency" to be able to change color and transparency on a PO index
- G4OpenGLViewer :
  o Add a "fIsGettingPickInfos" parameter to avoid problems
  o Split "Pick" function in 2 parts : "Pick" and "GetPickDetails"
  o Add a inner class "G4OpenGLViewerPickMap"

7nd July 2014  Laurent Garnier  (opengl-V10-00-11)
- G4OpenGLViewer :
  o Fix a warning

7nd July 2014  Laurent Garnier  (opengl-V10-00-10)
- G4OpenGLViewer :
  o Replace deprecated gluLookAt by g4GluLookAt

2nd July 2014  Laurent Garnier  (opengl-V10-00-09)
- G4OpenGLQtExportDialog : Remove unused functions
- G4OpenGLQtViewer :
  o Remove unused functions
  o Factorisation of Qt save function and OGL save functions.
- G4OpenGLViewer :
  o Move to private members from static members "fPrintSizeX", "fPrintSizeY", "fPrintFilename" and "fPrintFilenameIndex"
  o Change default export format to "pdf" instead of "eps"
  o Change default export name to "G4OpenGL-XXXX" where XXXX is the viewer_name
  o Change method signature for printEPS(), now return false when failed
  o printEPS() now deal with all gl2ps formats (eps/ps/pdf/svg)
  o Add a exportImage(name, width, height) generic function with lots of formats available
  o printGl2PS() : Better error messages
  o Renaming :
    o getRealPrintSizeX() to getRealExportSizeX()
    o getRealPrintSizeY() to getRealExportSizeY()
    o setPrintSize() to setExportSize()
    o setPrintFilename() to setExportFilename()
  o New methods :
    o addExportImageFormat()
    o setExportImageFormat()
    o exportImage(name, width, height) generic function with lots of formats available
    o isInitialized()
- G4OpenGLViewerMessenger :
  o Add new commands :
    o /vis/ogl/set/exportFormat
    o /vis/ogl/export

30th June 2014  Michael Kelsey
- G4OpenGLQtViewer:  Change QPixmap objects to be pointers; fixes fatal
  problem creating viewer in "batch" application without interactive GUI.

6th June 2014  Laurent Garnier (opengl-V10-00-08)
- G4OpenGLQtViewer: Fix a problem in viewer/set parameters

5th June 2014  Laurent Garnier (opengl-V10-00-07)
- G4OpenGLStoredSceneHandler : Split AddPrimitivePreamble() in 3 functions to avoid
  dynamic_cast (+20% faster in drawing)

5th June 2014  Laurent Garnier (opengl-V10-00-06 co-works interfaces-V10-00-05)
- G4OpenGLQtViewer:
  o Improve Viewer parameters info panel
  o Fix problem with /vis/viewer/set/ "auxiliaryEdge"/"defaultTextColour"/"globalLineWidthScale"
  o Implement missing commands : "edge", "lightsThetaPhi", "upVector", "viewpointVector"
- G4OpenGLImmediateQtViewer/G4OpenGLStoredQtViewer:
  o Add feedback for Viewer parameters info panel

3rd June 2014  Laurent Garnier
- G4OpenGLQtViewer:
  o Hide Viewer parameters under a widget at the bottom of the Viewer panel
  o Most of viewer/set parameters are now implemented. Still missing :
    "culling", "edge", "lightsThetaPhi", "upVector", "viewpointVector"

28th May 2014  Laurent Garnier
- G4OpenGLQtViewer: Add current parameters for targetPoint, lineSegmentsPerCircle, upThetaPhi

27th May 2014  Laurent Garnier
- G4OpenGLQtViewer: Viewer parameter panel improvments, all viewer parameters are editable

26th May 2014  Laurent Garnier
- G4OpenGLQtViewer: Beggining of DEV-151 : Add a viewer parameter panel
   o All view parameters with a "set" ui command are there.
   o Only viewpointThetaPhi has a feedback
   o All other parameters are default.

20th May 2014  Laurent Garnier
- G4OpenGLQtMovieDialog: Minor change in movie menu title

13th May 2014  John Allison  (opengl-V10-00-05)
- Coworks: DAWN-V10-00-02, visman-V10-00-08, openinventor-V10-00-01.
- Moved G4VisFeaturesOfOpenGL from management sub-category.

5th May 2014  Laurent Garnier  (opengl-V10-00-04)
- G4OpenGLQtViewer : Fix a bug in Picking in Qt viewer. A G4cout was missing in order
  to see picked informations

23th April 2014  Laurent Garnier (opengl-V10-00-03)
- G4OpenGL.hh: Fix bugzilla #1618 : for a Linux user, compiling Geant4 with only
  Qt driver will failed because of missing glu.h.

18th April 2014  Laurent Garnier
- G4OpenGLImmediateSceneHandler: Split AddPrimitivePreamble() in 3 functions to avoid
  dynamic_cast (+20% faster in drawing)

17th April 2014  Laurent Garnier
- G4OpenGLViewer : Time optimization in printEPS for Immediate mode
  => save 70-80% in drawing time on batch drawing. 10-20% when printing with a screen
     viewer

10th April 2014  Laurent Garnier (opengl-V10-00-02)
- G4OpenGLQtViewer : Add changing the color of text in DrawText()
- G4OpenGLViewer : manage bad file name case (missing directory) in printGl2PS()

5th February 2014  Laurent Garnier
- G4OpenGLStoredQtViewer : Bugfix for Qt5

25th January 2014  John Allison  (opengl-V10-00-01)
- G4OpenGLStoredSceneHandler::AddPrimitivePreamble:
  o Improved protection of pointers in display list reuse test.

23rd January 2014  John Allison  (opengl-V10-00-00)
- G4OpenGLViewer:
  o Switch off debug flag G4DEBUG_VIS_OGL.
  o G4OpenGLViewer::Pick:
    - Make virtual so it can be overloaded.
    - Return information in G4String.
    - Comment out debug printing.
- G4OpenGLXViewer::ShowView: Adapt to new G4OpenGLViewer::Pick.

9th December 2013 Laurent Garnier
- G4OpenGLViewer : Fix a warning

6th December 2013 Laurent Garnier
- G4OpenGLStoredQtViewer.cc
 o Fix (a part of) the picking problem (JIRA-DEV113)
 o Fix a potentiel problem with freezing OGL window with Qt driver
- G4OpenGLQtViewer :
 o Better size handling at start
- G4OpenGLViewer :
 o Prepare picking in order to display additional information on viewer (and not
   in G4cout)

20th November 2013 Laurent Garnier  (opengl-V09-06-12)
- G4OpenGLQtViewer : Fix a bug with endsWith that I have introduce in last revision

20th November 2013 Laurent Garnier  (opengl-V09-06-11)
- G4OpenGLQtViewer :
  o When saving file in Qt the extention was always append. Now it is done only when it is
    not present
  o Add a variable to remember last used settings for image type and target directory
  o Make PNG the default export format instead of BPM.
  o Add another protection against iterator outside of std::map

19th November 2013 Laurent Garnier (opengl-V09-06-10)
- G4OpenGLQtViewer :
  o Best fix for JIRA DEV-62, thanks John.

19th November 2013 Laurent Garnier
- G4OpenGLQtViewer :
  o Remove a printf without #ifdef
  o Fix a bug in the sceneTree viewer (probably JIRA DEV-62). A std::map iterator
    was incremented without checking if it going outside the std::map or not.

13th November 2013 Laurent Garnier
- G4OpenGLQtViewer : Better solution implementation for layouts management (does not fix any problems)

7th November 2013 Laurent Garnier (opengl-V09-06-09)
- Better solution for JIRA-Dev28 problem, also fix text justification in Qt

7th November 2013 Laurent Garnier
- Fix the JIRA-Dev28 problem : Text displays in wrong position in Qt

31th October 2013  Laurent Garnier (opengl-V09-06-08)
- Cleanup in the code, in particular Wt driver

31th October 2013  Laurent Garnier
- G4OpenGLWtDrawer : Move some function in an OpenGL generic way rather than only
  WebGL
- G4OpenGLImmediateWtViewer : Removed unused functions
- G4OpenGLSceneHandler :
  o Remove DrawText for OpenGL2 version for the moment
  o Better implementation of optimize vertex+indices for G4Cons
  o Enable/Disable VertexAttribArray not only for WebGL viewer

30th October 2013  Laurent Garnier
- G4OpenGLSceneHandler : Better emulation of GL_QUADS (and optimization)

30th October 2013  Laurent Garnier
- G4OpenGLViewer.hh, G4OpenGLSceneHandler.hh :
  o Add a setWtDrawer function to set the Wt drawer only when the
    OpenGLImmediateWtViewer is build
  o Move a lot of OpenGL2 functions and attributes from OpenGLImmediateWtViewer
    to be generic for all OpenGL drivers
- G4OpenGLImmediateWtViewer :
  o Move a lot of OpenGL2 functions and attributes from OpenGLImmediateWtViewer
    to be generic for all OpenGL drivers
  o At initialization, now set the WtDrawer for the OpenGLViewer and the SceneHandler
- G4OpenGLImmediateWt : Get rid of an include that could be done in a next step
- G4OpenGLWtDrawer : Add more methods for OpenGL
- G4OpenGLSceneHandler : Add some debug statements (WILL HAVE TO BE REMOVED)

26th October 2013  Laurent Garnier
- Introduce work for Wt driver. the major change is that with "normal" OpenGL,
  functions are statics and accessible everywhere. This is not the case for
  Wt OpenGL functions. They are only member functions of the WGLWidget because
  they have to be redefined to javascript commands to be send to all browsers
  using the applications. In term of changes in OpenGL library, this only one
  is the introduction of a G4OpenGLWtDrawer which is used to map static GL
  functions into member functions of WGLWidget object :
  o G4OpenGLViewer : Introduction of a pointer to to WtDrawer
  o G4OpenGL.hh : Include G4OpenGLWtDrawer
- Other changes in Wt component :
  o G4OpenGLImmediateWtViewer : Add methods to handle transformations on
    vertex position
- sources.cmake : Add G4OpenGLWtDrawer support
- Beginning of OpenGL >1.1 implementation : Alternative for glBegin/glEnd calls
  Will not change anything until G4OPENGL_VERSION_2 is not set (and only set
  for Wt driver for the moment)
  o G4OpenGLSceneHandler : Beginning of OpenGL >1.1 implementation

25th October 2013  Laurent Garnier
- G4OpenGLQtViewer :
  o Fix a problem on mouse right clic. It was first calling
    mouse left clic. This could cause some problems when switching between
    rotate/move/pick modes.
  o Fix typo in shortcuts

24th October 2013 : Ben Morgan (opengl-V09-06-07 : coworks with cmake-V09-06-30))
- sources.cmake : Update Wt configuration to use new configuration
  variables. This makes configuration more local to the G4OpenGL module.

23th October 2013  Laurent Garnier (co-works with cmake-V09-06-29)
- sources.cmake : Remove Qt5 configuration, it is now include in cmake.

17th October 2013  Laurent Garnier
- G4OpenGLSceneHandler : Find a better way to draw cubes using drawElements
- G4OpenGLImmediateWtViewer
  G4OpenGLViewer
  G4OpenGLQtViewer
  G4OpenGLSceneHandler
  o Add preliminary support for Vertex Buffer Object and Index Buffer Object

16th October 2013  Laurent Garnier
- G4OpenGLQtViewer : Fix a problem when MouseRightClick on mac, LeftClic was
  called before and cause some troubles

15th October 2013  Laurent Garnier
- G4OpenGLSceneHandler : Wt driver has now triangles faces in the good way

14th October 2013  Laurent Garnier
- G4OpenGLImmediateViewer,
  G4OpenGLImmediateSceneHandler,
  G4OpenGLViewer,
  G4OpenGLStoredViewer,
  G4OpenGLStoredSceneHandler,
  G4OpenGLSceneHandler,
  G4OpenGLImmediateWtViewer,
  o prepare all theses class to work with Wt driver (and OpenGL_3), lot
    of #ifdef statement will be removed

10th September 2013  Laurent Garnier
- G4OpenGLImmediateWtViewer:
  o Add color and point size on Wt driver

23th September 2013  Laurent Garnier
- G4OpenGLWtViewer G4OpenGLImmediateWtViewer G4OpenGLImmediateWt :
   o Wt driver progress. All definitions should be set. Only drawing lines
     is implemented for now.

4th July 2013  Laurent Garnier
- G4OpenGLQtViewer:
   o Better margin control and adding a tooltip on scene tree colour item
   o Add a parseSceneTreeAndSaveState() in order to save the scene tree state

17th June 2013  John Allison  (opengl-V09-06-06)
- G4OpenGLQtViewer: Commented out skeleton code below.

10th June 2013  John Allison  (opengl-V09-06-05)
- G4OpenGLQtViewer: Skeleton implementation of
    const std::vector<G4ModelingParameters::VisAttributesModifier>*
    G4OpenGLQtViewer::GetPrivateVisAttributesModifiers() const

1st May 2013 - Laurent Garnier
- Improvments about Wt driver configuration

25th April 2013  Laurent Garnier
- Add cmake configuration for Wt and Qt5,
  check in the code : "!!! ONLY QT4 to be comment with QT5"
- G4OpenGLQtViewer.cc : Add Qt5 support

26th March 2013  John Allison  (opengl-V09-06-04)
- G4OpenGLStoredQtSceneHandler.cc:
  o Commented out unused typedefs that give warnings with gcc-4.8.0.

21th March 2013  Laurent Garnier  (opengl-V09-06-03)
- G4OpenGLViewer : remove bad "printf" statement

20th March 2013  Laurent Garnier
- G4OpenGLQtExportDialog : change "TRUE" by "true"
- G4OpenGLViewer : add "const" on getWin...()
- G4OpenGLSceneHandler : Null pointer fix (thanks to XCode analyzer)

29th January 2013  John Allison  (opengl-V09-06-02)
- More Coverity fixes and un-doing of some previous ones.

13th January 2013  John Allison  (opengl-V09-06-01)
- Coverity fixes.

2nd December 2012  John Allison  (opengl-V09-06-00)
- Remove NURBS.

13th November 2012  Laurent Garnier (opengl-V09-05-53)
- G4OpenGLQtViewer
  o Fix bug #1385 on Linux at launch. Mouse context try to change before it is initialize.
    No problem for Mac OS X

2nd November 2012  John Allison (opengl-V09-05-52)
- G4OpenGLImmediateQtViewer,G4OpenGLStoredQtViewer :
  o Fix bug #1368, now Qt batch mode display a window and printEPS is working again

2nd November 2012  John Allison (opengl-V09-05-51)
- G4OpenGLStoredSceneHandler.cc:
  o Fixed bug in display-list-re-use algorithm.  (If touchables have
    been modified it is too risky to re-use display lists.)

2nd November 2012  Laurent Garnier
- G4OpenGLQtViewer : Fix a possible problem in batch mode for scene tree component

1st November 2012  John Allison (tagged: opengl-V09-05-50)

31st October 2012  Fred Jones
- Fix compiler warnings.

31st October 2012  Laurent Garnier
- G4OpenGLStored/ImmediateQtViewer: Fix a bug in batch mode for printEPS, size was not correct

30th October 2012  Laurent Garnier (tagged: opengl-V09-05-49)

30th October 2012  John Allison
- G4OpenGLQtViewer::toggleTransparency: Swapped true<->false.

29th October 2012  John Allison
- G4OpenGLViewer: The following data members have been made static with the
  following initial values, modifiable by: "/vis/ogl/set/printSize",
  "/vis/ogl/set/printFilename" and used by "/vis/ogl/printEPS", and thus
  are used by all OGL viewers.  fPrintFilenameIndex is initialised to zero
  and counts on for *all* viewers.
     G4int G4OpenGLViewer::fPrintSizeX = -1;
     G4int G4OpenGLViewer::fPrintSizeY = -1;
     G4String G4OpenGLViewer::fPrintFilename = "G4OpenGL";
     int G4OpenGLViewer::fPrintFilenameIndex = 0;

29th October 2012  Laurent Garnier
- G4OpenGLQtViewer : Comment out a method and fix a printing caracter non desired

27th October 2012  John Allison (opengl-V09-05-48, needs visman-V09-05-43)
- Finally solved problem of batch v. non-Qt session!!!
  o Introduced G4OpenGLQt, a base class for G4OpenGLImmediate/StoredQt
    graphics system factories.
  o Implemented G4OpenGLQt::IsUISessionCompatible().  This finds the original
    session, if any.  If the session is a G4UIbatch (which can happen if
    invoked from a command in a macro file), it uses GetPreviousSession
    (recursively if necessary - the command may call another macro or command)
    until the original session, if any, is found.  If there is no original
    session we assume the application is in batch mode, and allow a Qt window.
    It's OK to have a Qt window in batch - one can open a viewer, create a
    scene, set view parameters and /vis/ogl/printEPS.  If there *is* an
    original session, but it is *not* an G4UIQt, we flag it as incompatible.
    A "fallback" graphics system is found, if any, in /vis/sceneHandler/create.

26th October 2012  John Allison
- G4OpenGLImmediate/StoredQt.cc:
  o Use GetG4UIWindow() to tell if G4UIQt has been instantiated.
    Solves problem of batch v. non-Qt session.

23rd October 2012  John Allison
- G4OpenGLStoredViewer.hh:
  o Made CompareForKernelVisit virtual.
- G4OpenGLStoredQtViewer:
  o Introduced G4OpenGLStoredQtViewer::CompareForKernelVisit, which
    is identical to G4OpenGLStoredViewer::CompareForKernelVisit
    except for checking of VisAttributesModifiers, because
    G4OpenGLStoredQtViewer keeps track of its own touchable
    modifiers (fTreeItemModels, etc.).
- G4OpenGLQtViewer.cc:
  o Introduced code to capture changes to visibility (selection) in
    VisAttributesModifiers.  This adds to the code to capture colour
    and transparency introduced in opengl-V09-05-47.

18th October 2012  Laurent Garnier
- G4OpenGLQtViewer :
 o Fix a Qt < 4.5 issue for ColorDialog
 o Fix a Qt < 4.4 issue for GridLayout::itemAtPosition
 o Fix a crash at exit on Linux SLC5 (he is right!)
 o Fix a compilation warning on SLC5

13th October 2012  John Allison
- G4OpenGLSceneHandler.cc, G4OpenGLImmediateSceneHandler.cc,
  G4OpenGLStoredSceneHandler.cc, G4OpenGLStoredViewer.cc:
  o Moved depth testing out of display list for polylines and markers.
    This allows on-the-fly changing of hidden markers, i.e., without
    a kernel visit and rebuilding of display lists.

12th October 2012  Laurent Garnier
- G4OpenGLQtViewer:
  o Prevent context menu to be called in a non-interactive session

12th October 2012  John Allison (opengl-V09-05-47, co-works
interfaces-V09-05-20)
- G4OpenGLQtViewer:
  o Introduced some trial code for capturing touchable colour changes.
  o Changed values to references where possible.

12th October 2012  Laurent Garnier
- G4OpenGLStoredQt/G4OpenGLImmediateQt:
  o Improve instantiation of G4UIQt in all G4VInteractiveSession mode case

11th October 2012  Laurent Garnier
- G4OpenGLStoredQt/G4OpenGLImmediateQt:
  o Improve instantiation of G4UIQt in terminal mode case

10th October 2012  Laurent Garnier
- G4OpenGLStoredQt/G4OpenGLImmediateQt:
  o Improve instantiation of G4UIQt in batch mode case

9th October 2012  John Allison
- G4OpenGLSceneHandler::AddPrimitive(const G4Polymarker& polymarker):
  o Removed glEnable(GL_BLEND) and glBlendFunc(…).  They are in
    G4OpenGLViewer::InitializeGLView, which is, I think, all it needs.

9th October 2012  Laurent Garnier (opengl-V09-05-46, co-works interfaces-V09-05-19)
- G4OpenGLQtViewer/G4OpenGLStoredQtViewer/G4OpenGLImmediateQtViewer :
  o Change mapping of context menu/icon in order to get all working together.
    Now a click on an icon will change the mouse context menu.

7th October 2012  John Allison
- G4OpenGLStoredViewer::CompareForKernelVisit:
  o Added test of VisAttributesModifiers to list checked for kernel visit.

4nd October 2012  Laurent Garnier
- G4OpenGLQtViewer
  o Changing color on non touchables now ok (except text)
  o In DrawText, remove unnecessary (and wrong) glColor change
- G4OpenGLViewer
  o In DrawText, remove unnecessary (and wrong) glColor change
  o Use SetOrthogonalProjection/SetPerspectiveProjection/
    SetDefaultColour/SetDefaultTextColour instead of hard coded methods

3nd October 2012  Laurent Garnier
- G4OpenGLQtViewer :
  o Fix a bug when cloning scene tree in scene tree viewer (bad fix yesterday)
  o Change color for PO=-1 to "no color" instead of unspecified color

3rd October 2012  John Allison
- G4OpenGLSceneHandler, G4OpenGLStoredSceneHandler::AddPrimitivePreamble,
  G4OpenGLStoredQtSceneHandler::ExtraPOProcessing:
  o Protected the case of G4LogicalVolumeModel.

2nd October 2012  Laurent Garnier
- G4OpenGLQtViewer : Fix a bug when cloning scene tree in scene tree viewer

2nd October 2012  John Allison
- G4OpenGLStoredViewer.cc:
  o Improved algorithm in DrawDisplayLists so that if the
    transparency if changed in DisplayTimePOColourModification,
    the drawing order is honoured immediately, i.e.,
    without needing a rebuild.  Objects are drawn in the
    following order:
    . Opaque;
    . Transparent;
    . Markers and polylines that are "not hidden".
- G4OpenGLStoredSceneHandler:
  o Rationalised the recording of transparency in the PO/TO.  (It
    is not necessary to keep a separate flag for transparency; it
    is enough to inspect the alpha value of the colour.)

2nd October 2012  John Allison (opengl-V09-05-45)
- G4OpenGLStoredWin32Viewer.cc:
  o Re-add inclusion of missing header files on Win32

2nd October 2012  Laurent Garnier (opengl-V09-05-44)
- G4OpenGLStoredWin32.cc:
  o Re-add inclusion of missing header files on Win32

1st October 2012  John Allison (opengl-V09-05-43)
- G4OpenGLStoredViewer.cc:
  o Removed hidden marker from list of parameters that of changed trigger a
    kernel re-visit.  DisplayLists() can now cope with a change because the
    required information is in the PO/TO.

28th September 2012  Laurent Garnier (opengl-V09-05-42)
- G4OpenGLQtViewer:
  o Fixed compiler warning

28th September 2012  Gabriele Cosmo (opengl-V09-05-41)
- Explicitly include units header in G4OpenGLQtViewer.cc.

28th September 2012  Laurent Garnier (opengl-V09-05-40)
- G4OpenGLQtViewer:
  o Fixed compiler warning and remove dead code

27th September 2012  John Allison
- G4OpenGLImmediate/StoredSceneHandler.cc:
  o Fixed clang compiler warning.

27th September 2012  John Allison (opengl-V09-05-39)
- G4OpenGLStoredSceneHandler:
  o Removed RequestPrimitives.  Previously, G4OpenGLStoredSceneHandler had its
    own version of RequestPrimitives, which attempted to re-use a display list
    if the geometry object had been encountered earlier with a different
    transformation.  The transformation is kept in the PO and the display list
    is re-used.  One has to be careful about replicas and transformations.  Now
    this code has been moved to AddPrimitivePreAmble.

27th September 2012  John Allison (opengl-V09-05-38)
- G4OpenGLStoredSceneHandler,
  o Minor name changes to improve readability.
  o Added #include <typeinfo> to fix compiler warnings on Linux.
- G4OpenGLStoredViewer:
  o Fix to enable switching from hidden markers to non-hidden and transparent
    to opaque and v.v.
- G4OpenGLSceneHandler.cc:
  o Fix compiler warning on Linux.

27th September 2012  John Allison (opengl-V09-05-37)
- G4OpenGLSceneHandler, G4OpenGLImmediateSceneHandler, G4OpenGLStoredSceneHandler,
  G4OpenGLStoredViewer:
  o Major re-design of scene and transient processing:
    . Three categories foreseen:
      ~ Opaque
      ~ To be treated as transparent
      ~ To be treated as non-hidden.  This applies to markers and polylines if
        hidden markers is _not_ requested, which is the default so that
        trajectories are always visible even if drawing in surface style.
        To change this - /vis/viewer/set/hiddenMarker true.
    . Thus G4OpenGLSceneHandler::ProcessScene() is three-pass-capable.
    . Also G4OpenGLStoredViewer::DrawDisplayLists makes three passes.
    . Appropriate information is stored in the PO or TO.

26th September 2012  Laurent Garnier
- G4OpenGLQtViewer : Remove all "ApplyCommand"

25th September 2012  John Allison (opengl-V09-05-36)
- Tagged for system testing.

25th September 2012  Laurent Garnier
- G4OpenGLQtViewer : Fix a bug with setting color when changing vis parameters
  not taken in account

25th September 2012  John Allison (opengl-V09-05-35)
- G4OpenGLViewer:
  o Revert to previous version.  glColorMaterial now in G4OpenGLSceneHandler.
- G4OpenGLSceneHandler:
  o Uses glColorMaterial judiciously for wireframe and surface (hsr) drawing:
    . GL_FRONT_AND_BACK for transparent polyhedra;
    . GL_FRONT for opaque (since back surfaces always hidden).
  o However, use glMaterial as before for hidden edge (hlr and hlhsr).  Un-
    fortunately this means "temporary" changes of colour, such as may be obtained
    with the Qt viewer, are not respected.
- G4OpenGLImmediateSceneHandler, G4OpenGLStoredSceneHandler, G4OpenGLStoredViewer:
  o Paid proper respect to transparency_enabled (default = true).  If true use
    glColor4d, else use glColor3d.

24th September 2012  John Allison (opengl-V09-05-34 - needs interfaces-V09-05-15)
- G4OpenGLImmediate/StoredQt.cc;
  o Checked instantiation of G4UIQt.
- G4OpenGLViewer::InitializeGLView:
    // Material (for surface rendering) follows glColor at all times.
    glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
    glEnable(GL_COLOR_MATERIAL);
- G4OpenGLSceneHandler.cc:
  o Commented out all uses of glMaterial.  Material now determined by glColor, since
    we now specify glColorMaterial - see G4OpenGLViewer::InitializeGLView.
  o Changed glColor3d to glColor4d.
- G4OpenGLStoredViewer.cc:
  o Changed glColor3d to glColor4d (except for "head time").
- G4OpenGLViewer, G4OpenGLQtViewer.cc, G4OpenGLStoredSceneHandler, G4OpenGLXViewer.cc:
  o Changed glColor3d to glColor4d.

24th September 2012  John Allison (opengl-V09-05-33)
- Tidied headers and improved comments.

20th September Laurent Garnier
- G4OpenGLViewer.cc : Fix uninitialize value
- G4OpenGLQtViewer :
  o 10x faster when getting color or visibility on element
  o Avoid changing Vis Attributes when changing color on PO objects
  o Fix problem on close/expand sometimes when rebuilding the scene
  -> But last point means that the scene tree viewer is no longer working
  on changing color/transparency, will be fix in next commit

7th August 2012  Laurent Garnier
- G4OpenGLViewer : Fix layout problem on gl2ps text
- G4OpenGLXViewer : Typo

6th August 2012  John Allison  (opengl-V09-05-31)
- G4OpenGLSceneHandler and G4OpenGLStoredSceneHandler:
  o Protected against null result of dynmic_cast on viewer (shouldn't happen!!).

5th August 2012  Laurent Garnier
- G4OpenGLQtViewer.cc, G4OpenGLStoredSceneHandler.cc
  o Fix default 43903 43943 ...
  o Fix potentiel compilation warning

5th August 2012  Laurent Garnier  (opengl-V09-05-30, coworks interfaces-V09-05-12)
- G4OpenGLImmediateQtViewer : Minor fix
- G4OpenGLQtViewer.cc :
  o Now take in account the GUI (interface package) icons status for move/rotate/pick
  o Move scene tree widgets into tab instead of VBox
  o Implement Zoom In/Out function, now it zoom on a specific point

11th August 2012 Laurent Garnier
- G4OpenGLQtViewer.cc/G4OpenGLStoredQtViewer:
  o Remove /vis/viewer/select command when changing transparency
  o Fixed compilation warning
  o Beginning of removing /vis/geometry/set/colour commands

8th August 2012  John Allison  (opengl-V09-05-29)
- G4OpenGLQtViewer.cc: Fixed "unused parameter" warning.

8th August 2012  John Allison  (opengl-V09-05-28, coworks interfaces-V09-05-09)
- Tagged.

7th August 2012  John Allison
- G4OpenGLStoredSceneHandler:
  o Moved colour from display list to PO so that a sub-class may
    modify through the new virtual function below.
- G4OpenGLStoredViewer:
  o Added virtual void DisplayTimePOColourModification
          (G4Colour&, size_t /*currentPOListIndex*/) {}
    so that a sub-class may modify the colur/transparency.  (If the
    transparency is modified the rendering may not be optimal since
    the order of rendering is determined at POList construction time.)

30th July 2012 Laurent Garnier
- G4OpenGLQtViewer.cc :
  o Add search widget in scene tree
  o Double click now allow to change color/transparency

23th July 2012 Laurent Garnier
- G4OpenGLQtViewer.cc :
  o Do not apply changes to other viewer when moving scene tree slider
  o Fix a problem on scene tree with non touchable volumes

19th July 2012  John Allison
- G4OpenGLStored/ImmediateSceneHandler.cc:
  o Disabled GL_DEPTH_TEST and GL_LIGHTING for 2D objects, but see...
- G4OpenGLSceneHandler.cc:
  o Disabled GL_DEPTH_TEST and GL_LIGHTING for 2D lines and markers.

17th July 2012  John Allison  (opengl-V09-05-27)
- Fix Linux compiler warnings.

17th July 2012 Laurent Garnier
- G4OpenGLQtViewer.cc :
 o Fix a problem with Scene tree on mix with some transparent and non physical
   volumes.
 o Moving transparency slider does now do not change non physical volume hidden/visible.
 o Sort item in scene tree

17th July 2012  John Allison  (opengl-V09-05-26, co-works interfaces-V09-05-08)
- Tagged.
- Included Laurent's fix for text layout.

17th July 2012 Laurent Garnier
- G4OpenGLQtViewer.cc :
 o Fix text alignement problem

16th July 2012 Laurent Garnier
- G4OpenGLQtViewer :
 o Bug fix for transparent objects in scene tree
 o Bug fix when closing a viewer on scene tree
 o bug fix when playing with scene tree and active tab was an immediate viewer

16th July 2012  John Allison
- G4OpenGLXViewer::DrawText:
  o Removed glDisable (GL_DEPTH_TEST); glDisable (GL_LIGHTING).
  o Now 3D text is hidden, when appropiate, by volumes drawn in surface mode.
  o (The depth testing of 2D objects, including 2D text, is dealt with in
     the scene handler.)
- G4OpenGLSceneHandler::Begin/EndPrimitives2D:
  o Moved fProcessing2D to G4VSceneHandler.
  o Now may be used by all and any driver.

13th July 2012 Laurent Garnier
- G4OpenGLQtViewer : Updates in Scene tree viewer algorithm
  (speedup and fix transparency bug of 11th July).

11th July 2012 Laurent Garnier  (opengl-V09-05-25 co-works interfaces-V09-05-08)
- G4OpenGLStoredQtSceneHandler.cc, G4OpenGLStoredQtViewer.cc : change/rename fonction
- G4OpenGLQtViewer :
 o Change Scene tree viewer algorithm (still some bug in tree on transparent objects)
 o Move scene tree layout to "interfaces", this fix a "bad layout problem"
   some tags ago

5th July 2012  Gabriele Cosmo  (opengl-V09-05-24)
- Explicitly use inclusion of headers for system of units and physical
  constants, in plan to remove implicit inclusion from globals.hh.

3rd July 2012  John Allison  (opengl-V09-05-23)
- Fixed some Coverity warnings.

2nd July 2012  John Allison  (opengl-V09-05-22)
- G4OpenGLStoredViewer.cc:
  o Important bug-fix for non-display-list text (i.e., Qt).

27th June 2012  John Allison
- G4OpenGLStoredViewer.cc: Tidy.

18th June 2012  John Allison  (opengl-V09-05-21)
- G4OpenGLStoredViewer::DrawDisplayLists:
  o For special case of text that must be treated without a display
    list, call G4OpenGLSceneHandler::AddPrimitive(const G4Text&)
    directly and call glPushMatrix, glColor, etc., as would be in the
    display list.
  o Remove code that changed fMemoryForDisplayLists (was a bad idea!!).

16th June 2012  John Allison  (opengl-V09-05-20)
- G4OpenGLStoredSceneHandler::AddPrimitivePreamble:
  o Re-instated glDrawBuffer(GL_FRONT) when memory for display lists is
    unavailable.  It now draws further trajectories properly.
- G4OpenGLStoredX(m)Viewer::ShowView:
  o Removed functions altogether, so parent class functions are now used.
  o They were issuing an extra Clear/DrawView.
  o ShowView is invoked at end of run and was thus causing an
    unneccessary draw.
  o It also had the effect of losing the above-mentioned "further
    trajectories" at the end of run.

16th June 2012  John Allison  (opengl-V09-05-19)
- Added /vis/ogl/set/eventsDrawInterval.
  o By default, the screen is updated at the end of every event.
    Allowing OpenGL to buffer several events can make a big
    improvement in drawing speed.  E.g., with exampleB1, 1000 events
    took 5 seconds but with "/vis/ogl/set/eventsDrawInterval 100",
    only 1 second.

15th June 2012  John Allison
- G4OpenGLImmediateSceneHandler:
  o Added ClearTransientStore, which issues Set/Clear/DrawView.
- G4OpenGLStoredSceneHandler.cc:
  o G4OpenGLStoredSceneHandler::ClearTransientStore:
    Re-introduced Set/Clear/DrawView.

12th June 2012  Laurent Garnier  (opengl-V09-05-18)
- G4OpenGLQtMovieDialog.cc
  o Shadow clean.

8th June 2012  John Allison  (opengl-V09-05-17)
- G4OpenGLSceneHandler.cc, G4OpenGLXmSliderBar.cc,
  G4OpenGLStoredViewer.cc, G4OpenGLViewer.cc::
  o Shadow clean.
- G4OpenGLQtExportDialog.hh/cc, G4OpenGLStoredQtViewer.cc,
  G4OpenGLQtMovieDialog.cc, G4OpenGLQtViewer.cc,
  G4OpenGLImmediateQtViewer.cc:
  o Clean all possible shadows, but many remain because Q_OBJECT,
    qobject.h, qdialog.h, qgl.h and others use "s" and/or "sr".

29th May 2012  John Allison  (opengl-V09-05-16)
- G4OpenGLStoredQtSceneHandler.cc:
  o Reverted to opengl-V09-05-14 (r58177).
- Implemented proper treatment of transparency in OpenGL stored mode
  in the case that trajectories passed through or behind transparent
  persistent objects (detector components).  Required proper ordering
  of display list execution.
- G4OpenGLStoredViewer::DrawDisplayLists:
  o Now does two passes for a proper treatment of transparency.
- G4OpenGLStoredSceneHandler:
  o Added fDisplayOnSecondPassForTransparency to PO and TO.
- G4OpenGL(Immediate/Stored)SceneHandler:
  o Improved name - fSecondPassForTransparency, etc., instead of fSecondPass.

23rd May 2012  John Allison  (opengl-V09-05-15)
- Health Check 2012: Migrated (see management/History):
  o G4OpenGLSceneHandler: Added
      void G4OpenGLSceneHandler::ProcessScene()
      {
        G4VSceneHandler::ProcessScene();
        // Repeat if required...
        if (fSecondPassRequested) {
          fSecondPass = true;
          G4VSceneHandler::ProcessScene();
          fSecondPass = false;
          fSecondPassRequested = false;
        }
      }
  o G4OpenGLSceneHandler.cc:
    . Changed glDepthFunc (GL_LESS) to glDepthFunc (GL_LEQUAL) for
      hidden polylines and markers.
    . Changed glDepthMask (0/1) to glDepthMask (GL_FALSE/TRUE).
  o G4OpenGLStoredSceneHandler.cc, G4OpenGLStoredQtSceneHandler.cc:
    . Removed calls to G4OpenGLStoredSceneHandler::ClearTransientStore and
      G4OpenGLStoredSceneHandler::ClearStore.
    . Removed calls to Set/Clear/DrawView.
  o G4OpenGLImmediateSceneHandler:
    . Removed ClearTransientStore.
  o G4OpenGLStoredXViewer.cc:
    . Tidied.

22nd May 2012  John Allison  (opengl-V09-05-14)
- G4OpenGLQtViewer.cc: Fixed Linux compiler warnings.

22nd May 2012  John Allison  (opengl-V09-05-13)
- Tagged.

9th May 2012  Laurent Garnier
- G4OpenGLQtViewer, in scene tree
 o Fix problem with the PO index 0
 o Improve rendering on slider (send commands only if necessary)
 o Fix a color problem

5th May 2012  Laurent Garnier
- G4OpenGLQtViewer
 o Fix a bug on MacOS French keyboard for Plus key on viewer
 o Resolve problem on transparency in scene tree by sorting items instead
    of by PO index (what was done before)
 o Also check transformation in adding scene tree elements
 o Add a depth slider (in test)

27rd April 2012  Laurent Garnier
- G4OpenGLQtViewer : Add stuff for new transparency depth component (still some bugs)

24rd April 2012  Laurent Garnier
- G4OpenGLStoredQtSceneHandler: Remove comments and unused variable
- G4OpenGLQtViewer : Scene Tree improvments

23rd April 2012  John Allison
- G4OpenGLStoredSceneHandler:
  o Corrected some error messages.
  o Removed Set/Clear/Draw from EndModeling.  Should not be necessary.

23th April 2012 Garnier Laurent
- G4OpenGLStoredQtSceneHandler: Clear the tree when ClearStore and transient store
- G4OpenGLQtViewer: Add a color box on the scene tree items

10th April 2012  Pere Mato  (opengl-V09-05-12)
- G4OpenGLWin32Viewer.cc: Make it work for Win64
  replacing [Get|Set]WindowLong() by [Get|Set]WindowLongPtr() and GWL_USERDATA by GWLP_USERDATA

10th April 2012  John Allison  (opengl-V09-05-11)
- Tagged.

4th April 2012  John Allison
- opengl-V09-05-10: Don't use.
- X and Xm drivers: Implemented text layout and offset.
- Qt drivers: Text OK, but layout and offset not yet implemented.
- Win32 drivers: Text not implemented at all.

4th April 2012  Laurent Garnier
- G4OpenGLQtViewer : Fix many time tree items on non PV
- G4OpenGLQtViewer : Add tooltip and font on tree viewer

3rd April 2012  John Allison
- G4OpenGLXm classes: Change G4Exception id to opengl20xx.

3rd April 2012  Laurent Garnier
- G4OpenGLQtViewer & G4OpenGLQtSceneHandler : rewriting methods to add a
    PV or non P volume in the tree viewer

2nd April 2012  Laurent Garnier  (opengl-V09-05-09)
- Add some #ifdef around debugging printf

30th March 2012  John Allison
- G4OpenGLStoredSceneHandler.cc: In EndModeling, make sure screen
  corresponds to graphical database.
- G4OpenGLImmediateSceneHandler: Removed RequestPrimitives.  No
  longer needed since tests for transparency and second pass have
  been moved to AddPrimitivePreamble.

29th March 2012  Laurent Garnier
- G4OpenGLQtViewer : Add setHiddenMarker On/Off context menu
- G4OpenGLStoredQtSceneHandler: Add SetScene to clear Qt tree in
  case of scene change
- G4OpenGLStoredSceneHandler.cc: In EndModeling instead of COMPILE_AND_EXECUTE
  just COMPILE

28th March 2012  John Allison
- G4OpenGL(Immediate/Stored)SceneHandler: Correct treatment of
  transparent primitives.  (Previously, only transparent solids
  were corretly treated.)  This corrects a problem that when there
  existed a transparent solid, primitives were drawn twice!

28th March 2012  Laurent Garnier
- 1st version of Qt tree, still some bug to be solved

6th March 2012  John Allison  (opengl-V09-05-08)
- Fix problem with persistent text that does not use gl commands,
  e.g., Qt text.

29th February 2012  John Allison  (opengl-V09-05-07)
- Fixed minor problem with text:
  o Cleaned up display list drawing.  If special text (G4TextPlus), do
    not push, mult and pop matrix here (it is done in G4VScenehandler
    when it is re-used for text).
  o No need for transform in G4TextPlus.

28th February 2012  John Allison  (opengl-V09-05-06)
- Migrated to G4VScenehandler::fObjectTransformation.

28th February 2012  Laurent Garnier
- G4OpenGLStoredViewer.cc : Change matrix comparison

22th February 2012  Laurent Garnier
- G4OpenGLQtViewer.cc: fix a problem in max frame per second on little scenes

20th February 2012  Laurent Garnier
- G4OpenGLStoredViewer.cc : OpenGL optimisation. Small thing, but 50%
  faster when rotating

14th February 2012  John Allison  (opengl-V09-05-05)
- G4OpenGLStoredSceneHandler.cc:
  o Fixed bug in TO copy constructor.
  o This was causing text to be displayed in the wrong place.  Probably
    other transients too!!
- G4OpenGLSceneHandler.cc:
  o General tidy.
  o Several functions need to access data and/or methods in G4OpenGLViewer.
    static_cast doesn't work with a virtual base class, so use dynamic_cast.
    No need to test the outcome since viewer is guaranteed to be a
    G4OpenGLViewer.  Make usage consistent.
  o G4OpenGLSceneHandler::AddPrimitive (const G4Circle& text):
    . Removed glGetFloatv(GL_CURRENT_COLOR, color).
    . There is no need to save current colour; colour is defined for
      every primitive before drawing.

13th February 2012  John Allison  (opengl-V09-05-04)
- G4OpenGLStoredQtSceneHandler.cc: Added #include <typeinfo> for gcc 4.3.

11th February 2012  John Allison  (opengl-V09-05-03)
- Merged vis-V09-05-04-2ndbranch (tag vis-V09-05-04-2ndbranch-08) to trunk.
- G4OpenGLQtViewer : Remove unused method CreateFontLists()
- Exchange a GL_FRONT to GL_BACK drawing in the case of out of memory
  for display list.
- G4OpenGLViewer.cc: Bug fix in error message: maximum window size exceeded.

7th February 2012  John Allison  (vis-V09-05-04-2ndbranch-opengl-06)
- Needs greps-V09-05-05:
  o (G4VisAttributes and G4Visible copy constructor and assignment operator.)

7th February 2012  John Allison  (vis-V09-05-04-2ndbranch-opengl-05)
- PO/TOList: Changed G4Text* to G4TextPlus* (includes object transform
  and 2D flag).

4th February 2012  John Allison  (vis-V09-05-04-2ndbranch-opengl-04)
- Needs greps-V09-05-04 (G4Text copy constructor).
- PO/TOList: Changed G4TextModel* to G4Text*.

2nd February 2012  John Allison  (vis-V09-05-04-2ndbranch-opengl-03)
- G4OpenGLStoredSceneHandler.cc:
  o Removed glDrawBuffer(GL_FRONT) when no memory for display lists.
- G4OpenGLStoredViewer.cc:
  o Remove tempMFDL and associated code (see 1st February).The
    following renders it unnecessary.
  o When re-using AddPrimitive, by-pass the stored AddPrimitive to
    avoid making more display lists and other stuff in
    AddPrimitivePreamble, etc.  Use
      static_cast<G4OpenGLSceneHandler&>(fSceneHandler).
        G4OpenGLSceneHandler::AddPrimitive(...).
  o Fixes StoredQt text problem.

1st February 2012  John Allison  (vis-V09-05-04-2ndbranch-opengl-02)
- G4OpenGLStoredViewer::DrawDisplayLists:
  o Some systems, notably Qt, re-use model->DescribeYourselfTo(sceneHandler)
    but we don't want to create any further display lists, so...
      G4bool tempMFDL = fG4OpenGLStoredSceneHandler.fMemoryForDisplayLists;
      fG4OpenGLStoredSceneHandler.fMemoryForDisplayLists = false;
   ...and restore at the end.
  o However, back to square one... Text not drawn.  Why not?
    G4OpenGLQtViewer::DrawText get called so why doesn't it draw?
    (It seemed that without this fix, DescribeYourselfTo was creating
    a TO - again and again - and getting drawn that way.  But why
    does it not get drawn this way???)

31st January 2012  John Allison  (vis-V09-05-04-2ndbranch-opengl-01)
- G4OpenGLStoredQtViewer:
  o Removed DrawText, thereby allowing base class implementation
    G4OpenGLQtViewer::DrawText to operate.  Fixes text problem altogther!!

31st January 2012  John Allison  (vis-V09-05-04-2ndbranch-opengl-00)
- Special case text: skeleton.  Some systems, notabley Qt, process
  text in a special way; it cannot be stored in display lists.  So the
  text model pointer is stored in the PO/TO and processed separately.
  (PO = Persistent object, TO = transient object.)  The nested classes
  G4OpenGLStoredSceneHandler::PO and TO keep relevent information,
  e.g., the display list index or, in this case, when relevant, a
  pointer to the G4TextModel.
  o G4OpenGLStoredSceneHandler:
    . Added a G4TextModel* to PO and TO.
  o G4OpenGLStoredViewer::DrawDisplayLists:
    . If PO or TO has a G4TextModel*, DescribeYourselfTo(fSceneHandler).
  o G4OpenGLStoredQtSceneHandler::ExtraPO/TOProcessing:
    . Stores the G4TextModel pointer in the current PO/TO.
  o G4OpenGLStoredQtViewer::DrawText:
    . Added temporary print statement (prints text).

17th January 2012  Laurent Garnier
- G4OpenGLStoredQtSceneHandler : Add ProcessText method
- G4OpenGLStoredViewer : Remove DrawOutOfDisplayLists method (moved in G4OpenGLStoredViewerQt)
- G4OpenGLStoredQtViewer : Add DrawOutOfDisplayLists method

13th January 2012  John Allison (opengl-V09-05-02)
- Tagged.

3rd January 2012 Laurent Garnier
- G4OpenGLStoredViewer : add a method DrawOutOfDisplayLists () in order, for
  the moment, to be able to redraw text outside of display list
- G4OpenGLQtViewer : Remove unused method CreateFontLists()
- G4OpenGLStoredQtViewer : In ComputeView method, after DrawDisplayLists, now we call DrawOutOfDisplayLists in order to draw text. Also remove DrawText (only print a warning message)
- G4OpenGLViewer : Better information message
- G4OpenGLStoredSceneHandler : Add text in store mode special case for Qt viewer.
  Exchange a GL_FRONT to GL_BACK drawing in the case of out of memory for display list

2nd January 2012  John Allison  (opengl-V09-05-01)
- G4OpenGLImmediate/StoredQt/X/Xm/Wt.hh:
  o Removed #ifdef G4VIS... protection from header files so that they
    can be used for a possible dynamic library.  Of course, the
    protection remains on the implementation files.

16th December 2011  John Allison  (opengl-V09-05-00)
- G4OpenGLStoredSceneHandler.cc:
  o Corrected treatment of colour for transient objects that got
    slightly mangled in the changes of 15th Decemeber.  Colour should
    *not* be in the display list since in some circumstances we modify
    it (fade by time).  Instead it is kept in the TO object.

15th December 2011  John Allison
- The following changes from vis-V09-04-11-branch:
27th October 2001 JA (on vis-V09-04-11-branch).
- Transferred LoadAtts to sub-classes.
- G4OpenGLStoredViewer.cc: Improved drawing loop.
- G4OpenGLStoredSceneHandler.hh:
  o Removed fAddPrimitivePreambleNestingDepth.  (Care in
    G4OpenGLSceneHandler means it is no longer needed.)
26th October 2001 JA (on vis-V09-04-11-branch).
- Minor changes and exposure of some debug statements.
25th October 2001 JA vis-V09-04-11-01 (on vis-V09-04-11-branch).
  o G4OpenGLSceneHandler:
    . Needs G4Polymarker::G4Polymarker (const G4VMarker&).
    . Reworked AddPrimitive for G4Polymarker, G4Circle and G4Square.
    . Instead of polymarker calling multiple circles/squares, circles
      and squares create a polymarker of size 1 and call polymarker.
    . Removed AddCircleSquare, AddCircleSquareVector and DrawXYPolygon.
  o G4OpenGLBitMapStore: Removed.
    . No longer needed.  Circles and squares are drawn as GL_POINTS.  (Why
      did I not notice this option before; would have saved a lot of trouble.)

30th november Laurent Garnier  (opengl-V09-04-28)
- Fix pop up warning box at beggining
- Fix unitialize value before Gl init

30th November 2011 Ben Morgan (opengl-V09-04-27)
- sources.cmake : Ensure that Motif libraries appear before X11 libraries in
  link line. Prevents item 321 in the Motif FAQ regarding "non-widget child
  "dsm"' errors.

29th November 2011 Ben Morgan (opengl-V09-04-26)
- sources.cmake : Ensure that G4OpenGLXViewer is built when
  only Xm driver is enabled.

15th November 2011  John Allison  (opengl-V09-04-25)
- (opengl-V09-04-24 was a mis-tag.)
- G4OpenGLStoredQtSceneHandler::ExtraTOProcessing: Fixed compiler warning.
- G4OpenGLSceneHandler::AddPrimitivesCircle, AddPrimitivesSquare and
  AddCircleSquareVector:
  o Changed pass-by-value to pass-by-reference to avoid copying.

14th November 2011  Laurent Garnier  (opengl-V09-04-23)
- G4OpenGLQtViewer.cc : Fix a Q_EMIT macro if Qt version < 4.4

13th November 2011  John Allison
- G4OpenGLStoredQtViewer::DrawText: Limited warnings.

12th November 2011  John Allison  (opengl-V09-04-22)
- G4OpenGLQtViewer.cc: Fixed default auxiliary edge tick-mark.
- G4OpenGLStoredQtSceneHandler::ExtraTOProcessing:
  o Suppressed debug printing.

11th November 2011  John Allison  (opengl-V09-04-21)
- G4OpenGLViewer.cc: Coverity fix.

11th November 2011  John Allison  (opengl-V09-04-20)
- G4OpenGLStoredQtSceneHandler.hh/cc: Protected with
  #ifdef G4VIS_BUILD_OPENGLQT_DRIVER
- G4OpenGLQtViewer::viewComponentItemChanged:
  o Commented out unused lines to prevent compiler warnings.
- G4OpenGLViewer::DrawText, ChangePointSize and ChangeLineWidth:
  o Converted doubles to prevent compiler warnings.

10th November 2011  John Allison
- G4OpenGLStoredQtViewer.cc: Fixed compiler warning and tidied.
- G4OpenGLStoredQtSceneHandler.cc: Tidied.

9th November 2011  Laurent Garnier
- G4OpenGLViewer : Fix bug on printEPS vectored blank scene

7th November 2011  John Allison
- G4OpenGLViewerMessenger.cc:
  o ApplyCommand("/vis/viewer/refresh") after /vis/ogl/printEPS.

6th November 2011  Joseph Perl (opengl-V09-04-19)
- Retagged. previous tag was misapplied.

6th November 2011  John Allison (opengl-V09-04-18)
- Transparency still an issue:
  o Revert to "always select" (G4OpenGLStoredQtViewer::POSelected:
    return true;).
  o No tag of interefaces, therefore no "Viewer components" window.

6st November 2011  Laurent Garnier
- G4OpenGLQtViewer : Fix transparency problem

5st November 2011  Laurent Garnier
- G4OpenGLStoredQtViewer : Fiw a redraw problem for Qt (John)
- G4OpenGLQtViewer : Add label on tree

5st November 2011  Laurent Garnier
- Fix compiler warnings in
 o src/G4OpenGLStoredQtViewer.cc
 o include/G4OpenGLStoredSceneHandler.hh
 o include/G4OpenGLStoredViewer.hh

5st November 2011  Joseph Perl (opengl-V09-04-17)
- sources.cmake needs G4OpenGLStoredQtSceneHandler

5st November 2011  Laurent Garnier
- G4OpenGLQtViewer/ G4StoredQtViewer : Begin work for changing tree when changing tab

4st November 2011  Laurent Garnier
- G4OpenGLQtViewer : Improvments on touchable tree viewer
- Add files :
  o G4OpenGLStoredQtSceneHandler.hh
  o G4OpenGLStoredQtSceneHandler.cc

4st November 2011  Laurent Garnier
- G4OpenGLStoreViewer/ G4OpenGLStoreQtViewer : Add methods POSelected/TOSelected (John)
- G4OpenGLQtViewer :
  o Add method to manipulate tree volume
  o Add variables to check performance
  o Remove old tree volume methods (here for testing)
- G4OpenGLStoreSceneHandler : Add methods ExtraPOProcessing/ExtraTOProcessing (John)
- G4OpenGLStoredQt.cc : Implementation of StoreQtViewer (John)


4st November 2011  Laurent Garnier  (opengl-V09-04-15)
- Display message when using Text on Stored mode in Qt (problem not fixed)

27th October 2011  John Allison
- G4OpenGLStoredViewer.cc:
  o Unwrap PODLs (permanent object display lists, geometry volumes
    mainly).  Previously, the PODLs were called from a "top PODL".
    Instead, so that we can have control over which are drawn, they
    are called in a loop, like the TODLs (transient ODLs).  The is no
    measureable performance penalty, even on complex geometies.  (The
    top PODL still exists, but is not used; the corresponding code to
    call the top PODL is commented out.)
- G4OpenGLViewer.cc: Fix compilation warning.

27st October 2011  Laurent Garnier
- fix compilation warning on XCode

26st October 2011  Laurent Garnier
- Change minor things for ppmtompeg tool
- speed improvements in G4StoreViewer (+10%)

24st October 2011  Laurent Garnier
- G4OpenGLXViewer, G4OpenGLQtViewer, G4OpenGLViewer :
  o Change name of drawGl2psText in DrawText in order to be able to
    Draw gl2ps text even on viewers where no 2D text is implemented
- Fix problem with marker size on gl2ps
  o G4OpenGLViewer : Add two methods ChangePointSize and ChangeLineWidth

21st October 2011  Laurent Garnier
- G4OpenGLXViewer : move text positioning in SceneHandler (factorising)
- G4OpenGLSceneHandler : set text position
-> Fix bad positionning text in gl2ps
-> Fix text color in gl2ps

21st October 2011  John Allison  (opengl-V09-04-14)
- Tagged.

21st October 2011  Laurent Garnier
- G4OpenGLViewer : Fix missing text after printEPS in Immediate mode (need visexternal-V09-04-02 )

20th October 2011  Laurent Garnier
- G4OpenGLViewer
  o automaticaly extend gl2ps buffer size if needed
  o Add some error messages

19th October 2011  Laurent Garnier
- G4OpenGLSceneHandler :
  Fix a bug with marker, circle markers now appear with a circle marker
  For this, copy AddPrimitives in 2 methods
    AddPrimitivesCircle and AddPrimitivesSquare
-G4OpenGLViewer : add default parameter for gl2ps line width and point
  size in variable

18th October 2011  John Allison  (opengl-V09-04-13)
- Tagged.

17th October 2011  Laurent Garnier
- G4OpenGLXmViewer :
  o Fix null pointer when open Panning panel.
  o Add a UpdateControlPanel method

16th October 2011  John Allison
- G4OpenGLStoredSceneHandler.cc:
  o Moved
      if (fReadyForTransients) glDrawBuffer (GL_FRONT);
    from AddPrimitivePreamble to BeginPrimitives and
      ScaledFlush();
      glDrawBuffer (GL_BACK);
    from AddPrimitivePostamble to EndPrimitives.  The number of calls
    to glDrawBuffer and number of (scaled) flushes is reduced, i.e.,
    once per bunch of primitives instead of every primitive.

15th October 2011  John Allison (opengl-V09-04-12)
- G4OpenGLStoredXViewer, G4OpenGLStoredXmViewer:
  o Added ClearView (see note on 13th October re non-appearence of
    trajectories).
- G4OpenGLStoredSceneHandler.cc:
  o Move ScaledFlush back to AddPrimitivePostamble (see note of 13th Oct).
    This addresses the problem of seeing trajectories in real time
    as generated.  I was wrong to move it to EndPrimitives.  It has
    to be done on the front buffer, before switching back to the
    back buffer, so it has to be done for each primitive.  But now it's
    scaled, that's not a problem.

14th October 2011  Laurent Garnier
- G4OpenGLXmViewer : Implement ResetView method, move some parameters
  into .hh files. Call ResetView at beggining to set parameters

13th October 2011  John Allison
- G4OpenGLSceneHandler:
  o Introduced ScaledFlush to flush after every 100 primitives.
- G4OpenGLStoredSceneHandler:
  o Re-engineered to use ScaledFlush in EndPrimitives.  It was in
    AddPrimitivePostamble, i.e, it was getting a flush after each
    primitive, which is more often than necessary.  The flush should
    have been after each bunch of primitives, i.e., in EndPrimitives.
    (I think this is why drawing slowed down a couple of years ago.)
    Even so, a flush would happen too often, so it is scaled.
- G4OpenGLImmediateSceneHandler:
  o Use ScaledFlush in EndPrimitives.
- G4OpenGLStoredXViewer, G4OpenGLStoredXmViewer:
  o Implement ShowView, which calls DrawView, to handle non appearence
    of trajectories on some X servers, particularly Mac XQuartz.
    Re-visit this at some future date.

11th October 2011  John Allison
- G4OpenGLViewer::ResetView: Invoke G4VViewer::ResetView.
- Fix G4OpenGLXmViewer::get_boolean_userData (mask lower 16 bits).

11th Octobre 2011 Laurent Garnier
- move pan and rotation sensibility management in G4OpenGLViewer class
- Integrate free rotation in all GL viewers
- G4OpenGLQtViewer : Remove emit of non-used move/rotate signals, remove unused methods
- OpenGL viewer : Implement ResetView (useful for Xm and Qt for the moment)

7th October 2011 Laurent Garnier (opengl-V09-04-11)
- Fixed compilation warning on X Viewer.

6th October 2011 Laurent Garnier (opengl-V09-04-10)
- Fixed one more compilation error on Windows in G4OpenGLWin32Viewer.

3rd October 2011 Laurent Garnier (opengl-V09-04-09)
- Fix Warning with DrawText and compilation error on Windows.

26th September 2011  John Allison  (opengl-V09-04-08)
- Re-instated QWidget* fUIViewComponentsTBWidget.

23th September 2011  Laurent Garnier
- G4OpenGLViewers : uncomment the glDrawBuffer (GL_FRONT) at initialisation
- Add a flush in ShowView in Qt GL Viewers
- Some improvments about DrawText in OpenGL (Still some problems on Store Qt)

22th September 2011  Laurent Garnier
 -add DrawText() method for X and Qt viewers :

22th September 2011  Laurent Garnier
- G4OpenGLStoredSceneHandler : Add a parameter to wait until 100 lists generate until do a
  glFlush.  glFlush take about 90% time in store mode, divide glFluch  number by 100 will
  change the first vis time from 100% to 10+90/100 = 10,9%

20th September 2011  John Allison
- Fix transparency problem:
  G4OpenGLImmediateXViewer.cc, G4OpenGLStoredXViewer.cc,
  G4OpenGLImmediateXmViewer.cc, G4OpenGLStoredXmViewer.cc,
  G4OpenGLImmediateQtViewer.cc, G4OpenGLStoredQtViewer.cc,
  G4OpenGLViewer.cc:
  Move initial gl commands to G4OpenGLViewer::InitializeGLView,
  which is called from each particular viewer's Initialise or, in
  the case of G4OpenGLImmediate/StoredQtViewer::initializeGL, from Qt
  at initialisation.  This includes the following commands relevant to
  transparency, so they are now uniformly invoked for all viewers.
    glEnable (GL_BLEND);
    glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

17th September 2011  John Allison
- G4OpenGLQtViewer:
  o Removed SetView (it did nothing).
  o Removed unnecessary #include's.
- G4OpenGLViewer.cc: Fixed printf statement.
- Migrated to new G4Exception.

10th August 2011 Laurent Garnier
- Add flag to not include vis into tab widget if qApp is external
- Remove static-cast on int values

5th August 2011 Gabriele Cosmo (opengl-V09-04-07)
- Added protection to restrict inclusion of headers in the previous tag
  only for MacOS systems, where the problem is observed.

5th August 2011 Gabriele Cosmo (opengl-V09-04-06)
- Fix in G4OpenGL.hh for proper inclusion of <OpenGL/gl.h> and <OpenGL/glu.h>
  for Qt build, when GL/X11 is not selected.
  Fixes compilation problem happening in either GNUMake and CMake builds, when
  selection Qt/GL driver.

21st June 2011  John Allison
- Removed struct G4OpenGLViewerFeedback3Dcolor.  Not needed since G4 v.6.

17th June 2011 Ben Morgan (opengl-V09-04-05)
- sources.cmake : Added support for building Xm and Win32 components.

17th June 2011  John Allison  (opengl-V09-04-04)
- G4OpenGLViewer.cc: Re-instated cutaways in intersection mode.  (Seems
  they got accidentally commented out.)

16th June 2011  John Allison  (opengl-V09-04-03)
- Tagged.

16th June 2011 L. Garnier
- Fix conflict with qgl.h and GL/gh.h in include files

2nd June 2011  John Allison  (opengl-V09-04-02)
- Tagged.

27th May 2011 L. Garnier
- Fix bug G4OpenGLViewer.cc

26th May 2011 L. Garnier
- Fix compilation bug in G4OpenGLViewer.cc

25th May 2011 Ben Morgan
- sources.cmake : Added section to enable building of X11 component if user has
  requested this.
  Simplified addition of compile definitions so that all files in the category
  pick them up. This replicates the behaviour of the current Makefiles.

20th May 2011 L.Garnier
- G4OpenGLViewer.cc : Add methods for viewerComponent tree

17th May 2011  John Allison  (opengl-V09-04-01)
- G4OpenGLSceneHandler.cc,G4OpenGLXmConvenienceRoutines.cc:
  o Fixed gcc-4.6.0 warnings about unused variables.
- G4OpenGLViewer.cc: Fixed Coverity warning

13th April, 2011 L. Garnier
- G4OpenGLQtViewer, G4OpenGLStoreQtViewer, G4OpenGLQtMovieDialog: Fix some potentiel problems
  with other Signal/Slot systems (boost)

11th April, 2011 L. Garnier
- Coverity warning fix

6th April 2011 Laurent Garnier
- G4OpenGLQtViewer add flag for batch mode. It works !

2nd March 2011  John Allison
- G4OpenGLViewer.cc: Fix Coverity warnings.

2nd March 2011 Laurent Garnier
- Get rid of old Qt3 code

1st March 2011  Laurent Garnier
- Fix Xm OpenGL inclusion problem by invert moving GL include at the beginning

23st February 2011  Laurent Garnier
- Replace mpeg_encoder by ppmtompeg

10th January 2011  Laurent Garnier
- Try to fix mix between GL include from X11 and GL include from Qt (APPLE stuff)

7th January 2011  John Allison
- G4OpenGLViewerMessenger.cc: Fixed problem of missing return statements.

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

11th December 2010  John Allison
- Fixed some Coverity warnings.

13th November 2010  John Allison  (opengl-V09-03-10)
- Tagged.

10th November 2010  John Allison
- G4OpenGLStoredSceneHandler.cc: Added commented out debug lines.
- G4OpenGLStoredSceneHandler.hh: Corrected misleading comment lines.
- G4OpenGLXViewer.cc: Protected output with G4VisManager::GetVerbosity.

8th November 2010  John Allison  (opengl-V09-03-09)
- G4OpenGLStoredSceneHandler:
  o Removed fDisplayListBase (not needed; display list ids ARE re-used).
  o Improved display list limit message.

7th November 2010  John Allison
- G4OpenGLViewerMessenger.cc: Improved messages.

6th November 2010  John Allison
- G4OpenGLViewerMessenger.cc: displayListLimit>=10000.
- G4OpenGLStoredSceneHandler:
  o Made all display list management variables static.
  o Bug fix: reset fMemoryForDisplayLists flag.

5th November 2010  John Allison
- G4OpenGLStoredSceneHandler, G4OpenGLViewerMessenger:
  o Introduced a display list limit to avoid memory exhaustion.
  o Introduced /vis/ogl/set/displayListLimit.

8th October 2010  Laurent Garnier
- G4OpenGQtViewer.cc:
  o Add menu for changing text color, default color, background color
  o Toogle projection now call directly command instead of redefinding it

6th October 2010  John Allison  (opengl-V09-03-08 with co-working tags...)
- Co-working tags: interfaces-V09-03-12 + config-V09-03-08
- G4OpenGLStoredViewer.cc:
  o Added default colour and default text colour to list of parameters
    that trigger a kernel visit.

5th October 2010  John Allison
- G4OpenGLStoredViewer.cc: Time-slices fade to background colour.

5th October 2010  Laurent Garnier
- Change lots of shortcuts in Qt
- Add 'google earth like' rotation

23th June 2010  Laurent Garnier
- G4OpenGLImmediate/StoredQtViewer : Fix compilation warnings
- G4OpenGLQtViewer : Add protection on Vis Tab without UI Qt

4th June 2010  Laurent Garnier (opengl-V09-03-07)
- G4OpenGLImmediate/StoredQtViewer : Add protection against multiple
  repaint call. Add protection against resizeGl with bad values

3rd June 2010  John Allison  (opengl-V09-03-06)
- G4OpenGLImmediateSceneHandler: Re-instate
  // Make sure screen corresponds to graphical database...
  if (fpViewer) {
    fpViewer -> SetView ();
    fpViewer -> ClearView ();
    fpViewer -> DrawView ();
  }
  I was wrong - it *is* necessary.  If not there, events are not refreshed.
  So this and similar changes below are all back to geant4-09-03, including
  glFlush, which is still a big performance penalty on Mac's Snow Leopard.

3rd June 2010  John Allison  (opengl-V09-03-05)
- Restored following files to geant4-09-03 in interests of stable behaviour:
  o G4OpenGLStoredSceneHandler.cc
    Restored code removed in opengl-V09-03-03:
  // Make sure screen corresponds to graphical database...
  if (fpViewer) {
    fpViewer -> SetView ();
    fpViewer -> ClearView ();
    fpViewer -> DrawView ();
  }
  o G4OpenGLStoredXViewer.cc:
    Restore to geant4-09-03.  Restored code removed in opengl-V09-03-03:
      } else { // ADD TO AVOID KernelVisit=1 and nothing to display
        DrawDisplayLists ();
        FinishView ();
- Note: G4OpenGLImmediateSceneHandler: Same code commented out.  I think
  it's not necessary for immediate mode.

30th May 2010  John Allison  (opengl-V09-03-04)
- G4OpenGLSceneHandler: Added AddCompound(const G4VDigi&).

29th May 2010  John Allison  (opengl-V09-03-03)
- G4OpenGLImmediateSceneHandler.cc, G4OpenGLStoredSceneHandler.cc:
  Removed the following from ClearTransientStrore (was causing
  unnecessary drawing and flipping buffers?):
  // Make sure screen corresponds to graphical database...
  if (fpViewer) {
    fpViewer -> SetView ();
    fpViewer -> ClearView ();
    fpViewer -> DrawView ();
  }
- G4OpenGLStoredXViewer.cc:
  Commented out as follows in DrawView (was causing extra buffer swap,
  thus showing bad picture; can't recall why it was introduced):
      } else { // ADD TO AVOID KernelVisit=1 and nothing to display
        //DrawDisplayLists ();  ????????? (JA)
        //FinishView ();        ????????? (JA)

26th May 2010 Laurent Garnier  (opengl-V09-03-02)
 - G4OpenGLQtViewer : Some improvments with auto rotation mode.

20th May 2010 Laurent Garnier  (opengl-V09-03-01)
 Co-working tag : intercoms-V09-03-01, interfaces-V09-03-02
 - GNUMakefile, G4OpenGLQtViewer : Better inclusion of new tabs in UI part

11th May 2010  John Allison  (opengl-V09-03-00)
- G4OpenGLSceneHandler:
  o Use generic section and cutaway algorithm.
  o Follow change in generic section and cutaway interface.
- G4OpenGLViewer.cc:
  o Use generic section and cutaway algorithm.
  o Fix compiler warning (*p++).
  o Replace strdup by local inline code.

29th April 2010 Laurent Garnier
 - G4OpenGLSceneHandler : Speed Improvment by drawing vector of
   markers instead one by one

27th April 2010 Laurent Garnier
 - G4OpenGLStoredXmViewer : remove viewer form list at destruction
 - G4OpenGLViewer : Fix a problem when printing in gl2ps

9th March 2010 Laurent Garnier
 - G4OpenGLViewer : Fix clipping when resizing non square size windows
   Remove error message when no scene present.
 - G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer :
    - Add some protections if viewer is in tab
    -  fix some redraw probems when focus was outside frame
    - Add ShowView() and paintEvent() methods
    - DrawView method is now the same in Store and Immediate mode
 - G4OpenGLQtViewer : Add things for viewer in tabs

3rd March 2010 Laurent Garnier
- G4OpenGLViewer : Add protection against null pointer scene

27th January 2010  Gabriele Cosmo
- Fixed compilation warnings on G4OpenGLQtViewer and corrected compilation
  error when using Qt-3.

6th January 2010  Laurent Garnier (needs interfaces-V09-02-07 + laurent-QtUI_with_tabs_v1)
- GNUMakefile : Add include for interfaces/basic
- G4OpenGLQtWiewer : Integration into QtUI Tab

17th November 2009  John Allison  (opengl-V09-02-10)
- Tagged for vis tag.

17th November 2009  Gabriele Cosmo
- Fixed problem in the generation of dependencies on Windows for some
  files, due to redefinition of min and max macros from windows.h in
  G4OpenGL.hh.
- Fixed GNUmakefile.

3rd November 2009  John Allison  (opengl-V09-02-09 coworks greps-V09-02-03)
- Tagged for system testing.

3rd November 2009  Laurent Garnier
- G4OpenGLImmediateQtViewer, G4OpenGLStoredQtViewer : Protec Qt4 method
  introduce 13rd october 09 by ifdef

3rd November 2009  John Allison
- G4OpenGLXmPanningCallbacks: Fixed pView compilation problem.

21 October 2009 Laurent Garnier
 -  G4OpenGLQtViewer : Prepare to attach viewer In UI

21st October 2009  John Allison  (opengl-V09-02-08 coworks greps-V09-02-02)
- Added default AddCompound (const G4THitsMap<G4double>&) methods.
  o Prevents warnings about hiding - calls G4VSceneHandler base class.

15 October 2009 Laurent Garnier
 - G4OpenGLViewer.cc : Fix a problem with printing. On mac OSX version
   > 10.5.7? or Ubuntu > 9.04? AND with user account configure in french
   (or canadian I believe), the decimal point character was defined by
   "," (see LC_NUMERIC). This cause a problem on reading eps files.
   Changed "," to "."

13 October 2009 Laurent Garnier
 - G4OpenGLImmediateQtViewer/StoredQtViewer : some cleaning
 - G4OpenGLImmediateQtViewer : Remove picking to true at initialisation
 - G4OpenGLQtViewer.cc : Fix a redraw problem on mac OS X 10.6
 - G4OpenGLStoreQtViewer.cc,G4OpenGLImmediateQtViewer.cc : Fix width()
   and height() problem on mac OS X 10.6

29 September 2009  John Allison  (opengl-V09-02-07)
- Tagged.

18 August 2009 Laurent Garnier
 - G4OpenGLXmViewer : Fix a wrong initialization introduce by the
   new way of handling window size hints (January 2009)

29 July 2009, Laurent Garnier
 - G4OpenGLQtViewer : Ensure the GL frame size will be correct
   by setting a 0 size margin around

27 July 2009, Laurent Garnier
 - G4OpenGLStoredQtViewer : Remove picking to true at initialisation

20 May 2009, Laurent Garnier (opengl-V09-02-06)
 - Fixed compilation errors on WIN32-VC for WIN32 specific drivers.

18 May 2009, Joseph Perl (opengl-V09-02-05)
 - Correct G4OpenGLViewerMessenger.hh

14 May 2009, Laurent Garnier (opengl-V09-02-04)
 - G4OpenGLViewer : Add methods to manage print size and filename
 - G4OpenGLViewerMessenger : Added /vis/ogl/set/printSize
 - G4OpenGLViewerMessenger : Added /vis/ogl/set/printFilename
 - G4OpenGLQtViewer.cc,G4OpenGLXmMainMenuBarCallback.cc, renaming
   according to first point.

13 May 2009, Laurent Garnier
 - G4OpenGLStoredQtViewer.cc: Fix a second view redraw at ShowView() call
 - G4OpenGLQtViewer : Remove unuseful variables, renaming others
 - G4OpenGLViewer : Add method for resizing properly windows. Add methods
   to get window width, height and to know if size has changed
 - G4OpenGLQtViewer, G4OpenGLStoredQtViewer, G4OpenGLImmediateQtViewer,
   G4OpenGLXmViewer, G4XmWindowsHandlingCallback, G4OpenGLXViewer :
     Apply the previous changes.

6 May 2009, Laurent Garnier
 - G4OpenGLQtViewer.cc: Fix compilation warning and error with gcc4.4

28th April 2009, John Allison
 - G4OpenGLViewerMessenger.cc: Added return statement at end of every
   "if (command == ..." statement.  (Because of test for OGLS, it is
   not elegant to use "if...else if...else" structure.)

28th April 2009, Laurent Garnier
 - G4OpenGLXViewer,G4OpenGLViewer : End of moving printEPS and associated
   functions from GLXViewer to GLViewer.
 - G4OpenGLXViewer :
   - Remove debug methods
   - Add check in SetView() method
 - G4OpenGLViewer : Add a glReadBuffer before glReadPixel in grabPixel method

8th April 2009, Laurent Garnier
 - G4OpenGLBitmapStore.hh : BugFix correction for windows (introduce 2nd February ?)
 - G4OpenGLViewer.hh : move methods in private
 - G4OpenGLXViewer.hh : Add debug methods
 - G4OpenGLImmediateXmViewer.cc, G4OpenGLStoredViewer.cc, G4OpenGLStoredXmViewer.cc,
   G4OpenGLStoredXViewer.cc, G4OpenGLViewer.cc   : Add debug messages
 - G4OpenGLStoredXmViewer.cc,G4OpenGLStoredXViewer.cc, G4OpenGLStoredWin32Viewer.cc :
   - Add a DrawDisplay list in case of KernelVisit=1 and  nothing new to display.
   - Add a flush at the end of the view.
 - G4OpenGLViewer.cc :
   - Improve the fix and resizing when X/Y size was even (lack of precision
     in a /2)
   - Set line/point size at a default size when printing.
 - G4OpenGLXmWindowsHandlingCallbacks.cc : print method rename in printEPS
 - G4OpenGLXViewer.cc : Lot of changes, try to debug it. Pb when printing in pixmap
   mode on some windows size

6th April 2009, Joseph Perl (opengl-V09-02-02, then opengl-V09-02-03)
 - New tag to clean up all of the cases of files that changed only in the cvs id.

24th March 2009, Laurent Garnier (opengl-V09-02-01)
 - G4OpenGLViewer : Add a fix and resizing when X/Y size was even (lack of precision
   in a /2)

18th March 2009  John Allison
- G4OpenGLViewerMessenger.cc: printMode and transparency are available
  for all OGL windows (they were previously inadvertently hidden by
  an OGLS requirement).

16th March 2009, Laurent Garnier
 - G4OpenGLViewer : Add a check on max viewport dimensions when setting size.

4rd March 2009, Laurent Garnier
 - G4OpenGLQtViewer:
   - Suppress some warnings when saving file
   - Changing size is now allowed when saving (to save with better resolution than screen size)
 - G4OpenGLViewer:
  - Some renaming for print methods to be more clear about Vectored and non Vectored
  - Now using Gl2PS method to do PS (changes also in G4OpenGLXViewer and G4OpenGLQtViewer)
  - Suppress unuseful printX methods (heritated form XViewer)
  - Add methods to handle printVectored and NonVector cases
 - G4OpenGLViewerMessanger : Changes methods to get new G4OpenGLViewer methods to print

1st March 2009, Laurent Garnier
 - Remplacing glBitmap by GL_POINTS to draw marker : Speed improvment
  and gl2ps can now draw Markers.

16 February 2009, Laurent Garnier
 - Modifications in GNUMakefile for gl2ps.
 - G4OpenGLViewer,G4OpenGLViewerMessenger.cc,G4OpenGLXmMainMenubarCallbacks.cc
   ,G4OpenGLXmViewer.cc modified for gl2ps and some renaming "print" in
   "printVectoredEPS"

2nd February 2009  Laurent Garnier
- Improve Anticipate headers declaration in all files
- Factorize grabPixels function in G4OpenGLViewer
- Begin of refactoring printEPS function

22th January 2009  Laurent Garnier
- Fix bug in ratio and geometry on X/Xm/Qt/Win32 viewers

19th January 2009  Laurent Garnier
- Change G4DEBUG definition by G4DEBUG_VIS_OGL

12th January 2009  John Allison
- G4OpenGLViewer.cc: Pick up X and Y window size hints to define viewport.

2 December, Laurent Garnier
 - G4OpenGLImmediateXmViewer,G4OpenGLStoredXmViewer,G4OpenGLXmViewer
   G4OpenGLImmediateXViewer, G4OpenGLStoredXViewer, G4OpenGLXViewer,
   G4OpenGLXmWindowHandlingCallbacks,
   G4OpenGLImmediateQtViewer.cc, G4OpenGLStoredQtViewer, G4OpenGLQtViewer
   G4OpenGLImmediateWin32Viewer.cc, G4OpenGLStoredWin32Viewer, G4OpenGLWin32Viewer
   ->  Replace WinSize by fWinSize and some improvments about size initialization

 - G4OpenGLQtViewer.hh : Suppress WinSize private variable
 - Now Could pass XString like 400x600-0+0 to viewers and set position and location. It
   will work for Qt, X, Win32 for the moment.

24 October, Laurent Garnier (opengl-V09-01-03)
 - Change GEANT4_QT_DEBUG flag by QTDEBUG
 - Suppress unuseful DEBUG messages

12th October Laurent Garnier
 - G4OpenGLQtExportDialog : improvments for Qt3"
 - G4OpenGLQtViewer,G4OpenGLImmediateQtViewer,G4OpenGLStoreQtViewer : Add the name on OpenGlQt viewers
 - G4OpenGLStoredQtViewer,G4OpenGLImmediateQt, G4OpenGLStoredQt : Change OGLSQT and OGLIQT by OGLSQt and OGLIQt

2 October Laurent Garnier
 - Fix a crash when there was no scene.

28 July Laurent Garnier
 - Fix a bug in XmRotation panel introduce in last commit by myself.

20th June 2008  Laurent Garnier
 - Correct some warnings
 - Move rotation code of Xm and Qt in G4OpenGLViewer::rotateScene. Same code in now shared

12th June 2008  Laurent Garnier
 - Emit signals when moving/rotate scene, in order to get them in external app

28th Mai 2008  Laurent Garnier
 - Add mouse wheel zoom commands

28th April 2008  Laurent Garnier
 - Add better moc control/compilation step in GNUmakefile
 - Fix a problem when launching QT VIS without QT UI (N02 for example)

28th April 2008  John Allison  (opengl-V09-01-02)
- G4OpenGLStoredSceneHandler: Tidied constructors of nested classes.

4th April 2008  John Allison  (opengl-V09-01-01)
- Fixed DBL_MAX problem in 2D drawing:
  o changed G4OPENGL_DBL_MAX to G4OPENGL_FLT_BIG.
- Fix gcc-4.3.0 compiler warnings.

11th March 2008, Laurent Garnier
 - Resolve QT3 compilation errors

10th March 2008, Laurent Garnier
 - Add a dialog panel to make movies (Right button->Actions->Movie parameters)
 - Add ability to "auto rotate" volume launched with quick mouse move
 - Lots of improvments for Qt3
 - Improvments on moving steps with shortcuts
 - Could now select between orthogonal/perspective view mode

1st February 2008  John Allison
 - G4OpenGLQtViewer.cc: Fix #ifdef QT protection.
 - G4OpenGLSceneHandler.cc: Small improvement to logic of setting GL_LIGHTING.

30th January 2008, Laurent Garnier
 - Add moving camera on left/right/up/down arrown, going forward/backward
   on SHIFT+up/down, zoom in with +/- keys
 - Add a context menu entry for projection perspective/orthographic
 - Fix some bugs on windows in export dialog

15th January 2008, Laurent Garnier
 - Fixed some layout problems on export dialog box
 - Some improvements on exports formats
 - Fix a bug in the help command : The clic callback on a item was not
   working on windows
 - Fix a crash at exit when launched on a MAC.
 - EPS export format is now ready for Qt3
 - Add Vectoriel EPS export format
 - Fix an aspect ratio deformation when resize the widget
 - Fix a crash at launch with leopard
 - When selecting the "move" mouse action, this action was set even when
   mouse button was released. Fixed : Now we should clic to have the move action
 - GNUmakefile : Added a macro for moc file
 - Moc files : Suppression of all theses files. They are now autogenerated
   thanks to config/common.gmk

4th January 2008  John Allison  (opengl-V09-01-00)
- Implemented extended 2D interface.

30th November 2007  Laurent Garnier
- Improvements for Qt3
- moc files : Adding other versions for QT_MOC_REVISION 28,58 and
   59, but this is not the right solution..

19th November 2007  Joseph Perl (for Laurent Garnier) (opengl-V09-00-04)
- Added GEANT4_QT_DEBUG flag to more places

15th November 2007  John Allison  (opengl-V09-00-03)
- Re-introduced Qt files, now properly protected by cpp flags.
- cpp flags also added to some other files not previously properly protected.

15 Nov 2007, Laurent Garnier
 - G4UIQt,G4Qt : Adding a GEANT4_QT_DEBUG flag to hide all debug messages
 - G4UIQt,G4Qt : Compilation improvements for Qt3
 - G4UIQt,G4Qt : Minors corrections on G4UIQt helpWidget

14 Nov 2007, Laurent Garnier
 - G4OpenGLStoredQtViewer.cc : Correction of a bug with mouse move event in
     Qt4
 - G4OpenGLQtExportDialog_moc.cc, G4OpenGLQtViewer.cc, G4OpenGLQtViewer_moc.cc :
     Adding protection for Qt version between 4.0 and 4.2

13th November 2007  John Allison  (opengl-V09-00-02)
- Removed Qt files from tag.  File are still at head - need fixing.

13 Nov 2007, Laurent Garnier
 - G4UIQt,G4Qt : Moving all moc in one big file interface/G4UIQT_moc.cc,
   including Qt3 and Qt4 moc support

10th November 2007  John Allison  (opengl-V09-00-01)
- Moved WinSize_x, y to base class G4OpenGLViewer.
- Minor improvement in guidance for /vis/ogl/printEPS.

09 Nov 2007, Laurent Garnier
 - G4UIQt,G4Qt : Change all include directive to be compatible with Qt3

08 Nov 2007, Laurent Garnier
 - moc_G4OpenGLQtExportDialog.cc move in G4OpenGLQtExportDialog_moc.cc
 - moc_G4OpenGLQtViewer.cc move to G4OpenGLQtViewer_moc.cc

27 Sept 2007, Laurent Garnier
 - Adding sur files for G4UIQt driver :
   - G4OpenGLImmediateQt.cc
   - G4OpenGLImmediateQtViewer.cc
   - G4OpenGLQtExportDialog.cc
   - G4OpenGLQtViewer.cc
   - G4OpenGLStoredQt.cc
   - G4OpenGLStoredQtViewer.cc
   - moc_G4OpenGLQtExportDialog.cc
   - moc_G4OpenGLQtViewer.cc

28th September 2007  lgarnier
- first import of G4UI Qt files : Do not try to compil them

21st August 2007  John Allison  (opengl-V09-00-00)
- Removed redundant G4OpenGLXViewerMessenger.

25th May 2007  John Allison  (opengl-V08-03-03)
- G4OpenGLSceneHandler and G4OpenGLXViewerMessenger:
  Fixed gcc-4.1.2 compiler warnings.

25th May 2007  John Allison  (opengl-V08-03-02)
- G4OpenGLXViewer: Trapped glXMakeCurrent in Initialise function.

24th May 2007  John Allison  (opengl-V08-03-01)
- Fixes for SUN.

16th May 2007  John Allison  (opengl-V08-03-00)
- Fix compiler warnings on SLC4.
- Bug fixes:
  o Correct path /vis/ogl/set/printMode.
  o Add SetView to pixmap screen dump ("/vis/ogl/set/printMode pixmap"
    and "/vis/ogl/printEPS").

8th May 2007  John Allison  (opengl-V08-02-06)
- Moved vectored PostScript printing to G4OpenGLViewer.
- /vis/ogl/printEPS should work for all viewers, including Win32.
- Introduced /vis/ogl/set/printMode vectored|pixmap, currently only
  effective on X windows (and still somewhat buggy).

4th April 2007  John Allison  (opengl-V08-02-05 - needs visman-V08-02-04)
- Implemented picking for OGLSX ( as well as OGLIX).  Hopefully works
  for OGL*Win32.  Still doesn't work for OGL*Xm.

3rd April 2007  John Allison  (opengl-V08-02-04 - needs visman-V08-02-03)
- G4OpenGLStoredSceneHandler:
  o Re-organised display lists on a per-primitive basis, i.e., one
    display list per primitive.  (This is so that, except for text,
    the colour - or, rather, intensity - can be brought out of the
    display list into the TOList (Transient Object List) and
    controlled for the Display-by-Time feature.  Previously, if more
    than one primitive were drawn between BeginPrimitives and
    EndPrimitives, it would finish up all in one display list, colour
    commands included. Rationalises and fixes a rare bug in the
    Display-by-Time feature - see August 2006.)
  o Added AddPrimitive(const G4Polymarker&) so that it is treated as
    one primoitive to fit with the above re-organisation.
- Implemented picking for OGLIX.

25th March 2007  John Allison  (opengl-V08-02-03)
- Fix compiler warnings.

8th February 2007  John Allison  (opengl-V08-02-02)
- Fixed Windows problem with DBL_MAX.  (Introduced G4OPENGL_DBL_MAX.)
- G4OpenGLXViewer.cc: Small bug fix in print().  (Context was switched
  .but not switched back.  Not serious, because context was always set
  before normal drawing.)

9th January 2007  John Allison  (opengl-V08-02-01)
- Implemented bitmap markers for MarkerSizeType == screen.  (The old
  polygon implementation remains for MarkerSizeType == world.)
- Added G4OpenGLBitMapStore to assist the above.
- G4OpenGLXViewer::CreateGLXContext:
  o Bug fix: Added missing break in colormap lookup routine.

5th January 2007  John Allison  (opengl-V08-02-00)
- G4OpenGLSceneHandler.cc:
  o Followed change of signature of GetLineWidth in visman-V08-02-00.
  o Minor efficiency improvements.

21st November 2006  John Allison  (opengl-V08-01-09)
- Fixed compiler warnings.

1st November 2006  John Allison  (opengl-V08-01-08)
- Replace /vis/oglx/set/printEPS by /vis/oglx/printEPS.  The new command
  actually initiates a print, rather than set a flag for printing.

24th October 2006  John Allison  (opengl-V08-01-07)
- G4OpenGLStoredViewer.cc: Calculate light front horizon properly.
- G4OpenGLViewerMessenger.cc: Make refresh depend on auto-refresh.

19th September 2006  John Allison  (opengl-V08-01-06)
- Added time origin for light front.
- Added /vis/ogl/set/transparency.
- G4OpenGLStoredViewer.cc: Bug fix in time range acceptance.

4th September 2006  John Allison  (opengl-V08-01-05)
- Implement cutaways.
- Immediate mode: G4OpenGLImmediateSceneHandler.cc: Flush all
  primitives (see detector being drawn).
- /vis/oglx/set/printEPS: change parameter default to true.

30th August 2006  John Allison  (opengl-V08-01-04)
- G4OpenGLSceneHandler:
  o Implemented line width.
  o Switched off back face culling when clipping so that the inside of
    volumes can be seen.
  o Added CreateSection/CutawayPolyhedron to exploit generic
    sectioning (DCUT) and cutaways.  Currently not activated due to
    instabilities in BooleanProcessor.  Local sectioning still active
    but broken (at least on Mac) due to apparent change in effect of
    clipping planes (polyhedron edges not reconstructed).
  o Rationalised calculation of marker size.
- G4OpenGLStoredSceneHandler:
  o Fixed bug due to recursive calls of AddPrimitive (polymarkers -> markers).
  o Pick up time range from G4VisAttributes.
- G4OpenGLViewer(Messenger):
  o Added position and colour to /vis/ogl/set/displayHeadTime.
  o Added /vis/ogl/set/displayLightFront.
- G4OpenGLStoredViewer.cc:
  o Rationalised CompareForKernelVisit.  (Local sectioning still active.)
  o Added position and colour to DisplayHeadTime.
  o Added DisplayLightFront.

16th August 2006  John Allison  (opengl-V08-01-03)
- Corrected Solaris compilation error.
- Added /vis/ogl/set/fade and displayHeadTime.

14th August 2006  John Allison  (opengl-V08-01-02)
- Needs visman-V08-01-02.
- G4OpenGLStored: Implemented display-by-time.  Only available in
  stored mode at present.  Only implemented for circle, square,
  polyline and polymarker at present, enough for currently available
  trajectory models.  Time is communicated via G4AttValues.
- Added G4OpenGLViewerMessenger.
- Added /vis/ogl/set/startTime and endTime of displayed objects.
- All factories: Instantiated G4OpenGLViewerMessenger.
- G4OpenGLViewer: Added fStart/EndTime.
- G4OpenGLXViewer.cc: Graceful recovery from unexpected tokens in
  spewPrimitiveEPS and spewSortedFeedback.

17th July  John Allison  (opengl-V08-01-01)
- Added /vis/oglx/set/printEPS (prints eps file on every update).

3rd July 2006  John Allison  (opengl-V08-01-00)
- Elimination of redundant variable doublebuffer and implementation of
  FinishView in all viewers.

30th May 2006  Joseph Perl  (opengl-V08-00-08)
- G4OpenGLImmediateWin32Viewer: Removed tests on doublebuffer since that
  variable seems to have random behavior and should be assumed false for
  this viewer.

29th May 2006  Joseph Perl  (opengl-V08-00-07)
- G4OpenGLWin32Viewer, G4OpenGLImmediateWin32Viewer, G4OpenGLStoredWin32Viewer:
  Removed common FinishView and instead made separate FinishView for the two different
  versions of this viewer since each wants a different buffer swapping behaviour.

12th May 2006  John Allison  (opengl-V08-00-06)
- G4OpenGLWin32Viewer: Fixed buffer swapping behaviour.

28th April 2006  John Allison  (opengl-V08-00-05 - needs visman-V08-00-14)
- G4OpenGLStoredX/Xm/Win32Viewer.cc: Fixed buffer swapping problem when
  recomputing transients.

24th April 2006  John Allison  (opengl-V08-00-04)
- Fixed compilation problem on Windows.

19th April 2006  John Allison  (opengl-V08-00-03)
- G4OpenGLSceneHandler, G4OpenGLStoredSceneHandler and
  G4OpenGLImmediateSceneHandler:
  o Implemented Begin/EndPrimitives2D (needs visman-V08-00-12 and
    greps-V08-00-02).
  o Migrated to direct access to G4PhysicalVolumeModel.
- G4OpenGLStoredX/Xm/Win32Viewer.cc: bug fix for conditional drawing
  of display lists in DrawView.

14th March 2006  John Allison  (opengl-V08-00-02)
- Refined display list building and re-drawing algorithm.
  o G4OpenGLStoredSceneHandler::EndModeling: Changed to GL_COMPILE_AND_EXECUTE.
  o Avoided unnecessary re-execution in DrawView (X, Xm and Win32).
- G4OpenGLStoredSceneHandler::RequestPrimitives: Refined display list
  re-use algorithm.  In test19 with global culling off, numbers of
  display lists used are:
  o 191  No re-use:
  o  73  Before this change: re-use except replicas (includes parameterised).
  o  33  After this change: re-use except parameterised and replicas in radius.

26th January 2006  John Allison  (opengl-V08-00-01)
- Coworks with visman-V08-00-04 (removed fModified).
- Removed references to fModified.
- Tidying: Removed unnecessary ClearView.
- G4OpenGLSceneHandler.cc: Added some (commented out) code for
  possible future implementation of 2D drawing.
- G4OpenGLXViewer.cc: Improved exception printing.

11th January 2006  John Allison  (opengl-V08-00-00)
- Improved efficiency: all DrawView's:
  o Don't call ClearView.
  o Set flag so SetView will not be called in ProcessView.
  o Leave background colour to ClearView.
- Used dynamic_cast<G4OpenGLViewer*>, no need for G4OpenGLViewerDataStore.
- G4OpenGLXmViewerMessenger: Made a smart singleton; interrogates vis manager
  for current viewer.

24th November 2005  John Allison  (opengl-V07-01-09)
- Protected G4OpenGLXmViewerMessenger with #ifdef G4VIS_BUILD_OPENGLXM_DRIVER.

22nd November 2005  John Allison  (opengl-V07-01-08)
- Added G4OpenGLXmViewerMessenger.
- Corrected text position.
- Made depth test for polyhedron GL_LEQUAL (slightly dominant).

17th November 2005  Gabriele Cosmo
- Fixed settings of background style for WIN32 viewers.

13th November 2005  John Allison  (opengl-V07-01-07)
- Implemented X-Window-style geometry hints in G4OpenGLXViewer.

13th October 2005  John Allison  (opengl-V07-01-06)
- Allowed any colour background.
- Implemented non-uniform scaling.
- Migration to <sstream>.

29th September 2005  John Allison  (opengl-V07-01-05)
- Added G4OpenGLViewerDataStore to facilitate access of viewer data by
  scene handler.
- Re-implemented transparency button in OpenGLXm.

13th September 2005  John Allison  (opengl-V07-01-04 - needs visman-V07-01-02)
- Implemented white background for all OGL viewers.
- G4OpenGLSceneHandler.cc:
  o Fixed hidden line removal (bug introduced in opengl-V07-01-02).
  o Fixed treatment of triangular polygons for drawing of auxiliary/soft lines.
  o Corrected GetTextColour(text).
  o Corrected GetColour(polyhedron).

5th September 2005  John Allison  (opengl-V07-01-03)
- Bug fix: stored transparent objects were being lost.

2nd September 2005  John Allison  (opengl-V07-01-02 - needs visman-V07-01-01)
- Bug fix: edgeflags problem introduced with smooth shading in
  opengl-V07-01-00.
- Implementation of a "better algorithm" for the rendering of
  transparent polyhedron objects.  It renders all opaque objects
  first, then renders the transparent objects with the depth buffer in
  read-only mode (see OpenGL Programming Guide).  It uses the new
  facility in G4VSceneHandler::ProcessScene for an optional second pass
  of the run-duration models in the scene.  Note this algorithm is
  still only an approximation.  It will still give the wrong blended
  colour if two transparent objects are rendered front first.  For
  nested transparent objects, this is unfortunate, because
  G4PhysicalVolumeModel traverses Geant4's mother-daughter hierarchy
  in such a way that mothers come first.  Also, there is no guaranteed
  relationship between the order of rendering and the depth of two
  transparent objects if they are at the same level or in different
  branches of the hierarchy.  Still, the only error will be an
  incorrect colour - the objects will still give the appearance of
  transparency, so it's a pretty good algorithm.  (An even better
  algorithm would be to attempt to render the facets in depth order,
  deepest first.  But how do you calculate the depth - centre of area,
  deepest corner?  One can still imagine pathalogical cases that would
  sometimes give the wrong colour.  Also, for stored mode, the order
  is fixed in a display list so when the user rotates the view, one
  would lose the depth ordering.  I think we have to accept that
  blending in OpenGL is only ever an approximation.  For accurate
  blending, use RayTracer.)

28th August 2005  John Allison  (opengl-V07-01-01)
- Half-way implementation of rendering of transparent polyhedron
  objects.  In this implementation, no account is taken of the order
  of rendering.  Transparent objects are rendered with depth testing
  off so that objects behind can still be seen.  But this means that
  opaque objects in front do not obscure them - and they jolly well
  should!  A better algorithm is to render all opaque objects first,
  then render the transparent objects with the depth buffer in
  read-only mode (see OpenGL Programming Guide).  This is going to
  take a little more thought - see opengl-V07-01-02.

20th July 2005  John Allison  (opengl-V07-01-00)
- Introduced smooth shading, taking advantage of hitherto un-noticed
  feature of HepPolyhedron::GetNextFacet that calculates the normals
  at each vertex so that curved surfaces are rendered more
  realistically (Gouraud shading).
- G4OpenGLImmediateSceneHandler.cc: Removed unnecessary #include's.
- G4OpenGLXmViewer.cc: Fixed to use window size hints.  This changes
  the default window size.  It used to be 400x400, hardcoded in
  G4OpenGLXmViewer.cc, but now it picks up the
  G4ViewParameters::GetWindowSizeHintX/Y, which defaults to 600x600.
  The user may change it on the command line, e.g:
    /vis/open OGLSXm 500
  or
    /vis/viewer/create ! ! 500

30th May 2005  John Allison  (opengl-V07-00-03)
- Fixed compilation problem in OpenGL on SUN.  (Replaced multimap by
  map of vectors in G4OpenGLFontBaseStore.)

4th May 2005  John Allison  (opengl-V07-00-02)
- Restored sequence Set/Clear/DrawView in ClearTransientStore.  (It
  was taken out to prevent recursive calling, but that seems to be OK,
  and it is needed to implement refresh at end of event/run.)

22nd April 2005  John Allison  (opengl-V07-00-01)
- Rationalised work of opengl-V07-00-00.  Functionality unchanged.
  o G4OpenGLViewer.hh: Created virtual void CreateFontLists(){}.
  o In all concrete viewers, added call to CreateFontLists().
  o Moved font code for X to G4OpenGLXViewer::CreateFontLists().
  o There is no longer a need to implement in the XmViewer, since it
    now inherits.  Thus the font code now only appears once for X.
  o Awaiting implementation for WIN32.

17th April 2005  John Allison  (opengl-V07-00-00)
- Based on vis-V07-00-13.
- Implemented text for X-Windows viewers.  Uses glXUseXFont, which
  creates display lists for nominated fonts.  Simple-minded scheme in
  which each viewer creates its own font display lists for a variety
  of sizes, which are accessed by the scene handler through a new
  class, G4OpenGLFontBaseStore.  Affected methods:
    G4OpenGLXViewer::CreateMainWindow()
    G4OpenGLXmViewer::CreateMainWindow()
    G4OpenGLSceneHandler::AddPrimitive (const G4Text& text)

18th November 2004  John Allison  (opengl-V06-02-07)
- Removed redundant fLastVP from G4OpenGLStoredSceneHandler.

15th November 2004  Guy Barrand
- G4OpenGLWin32Viewer::ShowView : glFlush was not sufficient
  to see trajectories (for example with N03). Correct so that
  ShowView do a FinishView that does : glFlush, wglSwapBuffer
  and empty the Windows message queue.

22nd September 2004  John Allison  (opengl-V06-02-06)
- doxygen output to tmp area.
- Trap non-regular polyhedrons.

13th September 2004  Gabriele Cosmo  (opengl-V06-02-05)
- G4OpenGLTransform3D.cc: simplified implementation for GetMatrix()
  to allow for porting on CLHEP-1.9.X series.

23rd July 2004  John Allison
- Draws auxiliary edges if required.
- Added auxiliary edge button.

16th July 2004  John Allison  (opengl-V06-02-04)
- Refinements to hidden line, hidden surface removal.

14th July 2004  John Allison  (opengl-V06-02-03)
- Removed superfluous #include "G4VisManager.hh" from G4OpenGLXmViewer.cc.

13th July 2004  John Allison  (opengl-V06-02-02)
- Hidden line *and* hidden surface removal now works.

9th July 2004  John Allison  (opengl-V06-02-01)
- Fixed long-standing problem with hidden line removal.
- Improved messages on failure to get visual.
- Added GLX_STENCIL_SIZE explicit request to visual attributes - most
  systems provided by default anyway, so no effect.

1st July 2004  John Allison  (opengl-V06-02-00)
- Rationalised G4OpenGLSceneHandler ready for hidden line removal.
- Bug fix in G4OpenGLXmPanningCallbacks.cc for dolly control.

18th June 2004  Gunter Folger (geant4-06-02)
9th June 2004  Gabriele Cosmo  (vis-V06-01-03)
7th June 2004  Gabriele Cosmo  (vis-V06-01-02)
- GNUmakefile and disclaimer changes - see visualization/History.

9th April 2004  John Allison  (vis-V06-01-01 + interfaces-V06-01-00)
- Tagged OpenGL as below.  Joint with interfaces-V06-01-00.

7th April 2004  Guy Barrand
- visualization/OpenGL/* : use the G4OpenGL.hh file.
- Added : visualization/OpenGL/include/G4OpenGL.hh to encapsulate
  the include of gl/gl.h and gl/glu.h that may be platform dependant.
  It permits to rm some #ifdef WIN32 spread in the code. It opens also
  the way to the usage of the Apple OpenGL on a Mac.

17th February 2004  John Allison  (opengl-V06-00-00)
- Fixed bug #581: wrong order of statements in
  G4OpenGLXViewer::~G4OpenGLXViewer (see bug report).

4th October 2003  Gabriele Cosmo  (vis-V05-02-01)
- GNUmakefile:
  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)
- Cosmetic change to regularise names:
  o changed _Feedback3Dcolo to G4OpenGLXViewerFeedback3Dcolor.
  o changed _DepthIndex to G4OpenGLXViewerDepthIndex.

23rd June 2003  Guy Barrand  (opengl-V05-01-02)
- Commit a first implementation of G4OpenGLWin32Viewer.

10th June 2003  Gabriele Cosmo  (opengl-V05-01-01)
- More fixes for warnings in viewers classes.
- Added inclusion of <windows.h> for WIN32 platforms when GL headers
  are included.

05th June 2003  Gabriele Cosmo  (opengl-V05-01-00)
- Fixes for porting compilation on WIN32:
  o G4OpenGLWin32Viewer[.hh.cc]: removed inclusion of <GL/glx.h>.
  o G4OpenGLViewer.cc: replaced local variables near/far with pnear/pfar
    since declared 'obsolete' in WIN32 platforms.

27th November 2002  John Allison  (vis-V04-01-08)
- Improved algorithm of CompareForKernelVisit.

11th November 2002  John Allison  (opengl-V04-01-02)
- Corrected inclusion of G4OpenGLXViewer #ifdef X_DRIVER.
- Added G4OpenGLSceneHandler::AddThis for trajectories and hits - simply
  call default but there as a marker and encourager.
- Added tracking and digits+hits/hits to GNUmakefile.

16th October 2002  John Allison  (opengl-V04-01-01)
- Fix for WIN32.  Now compiles but viewer not implemented.

24th June 2002  John Allison  (opengl-V04-01-00)
- Further cosmetic changes in G4OpenGLXViewer.cc for DEC compiler.

10th June 2002  John Allison  (opengl-V04-00-03)
- Cosmetic changes for SUN-CC in G4OpenGLXmConvenienceRoutines.cc.

6th June 2002  John Allison  (opengl-V04-00-02)
- Cosmetic changes for GNU compiler in G4OpenGLXViewer.cc.

23rd February 2002  John Allison  (opengl-V04-00-01)
- Changes to encourage compilation on Windows in preparation for
  implementation of G4OpenGLWin32Viewer.  Removed spurious includes of
  glx.h, unistd.h and assert.h.

24th August 2001  John Allison  (vis-V03-02-13)
- Limited the printing of warnings in
  G4OpenGLSceneHandler::AddPrimitive (const G4Text& text).

14th August 2001  John Allison  (vis-V03-02-11)
- Improved KernelVisitDecision.
- Fixed a few small bugs in multiple "stored" viewers, but see next item.
- There's an outstanding bug in OpenGL Stored.  If there is more than
  one viewer controlled by a scene handler, after a ClearStore on the
  scene handler, e.g., with /vis/scene/notifyHandlers, the first
  viewer to get refreshed should trigger the display list rebuild, but
  the second need not.  However, when the second viewer's turn comes,
  the display lists are there, and are called, e.g.,
  G4OpenGLStoredXViewer::DrawView calls
  G4OpenGLStoredViewer::DrawDisplayLists that calls glCallList, but
  nothing appears on the screen.  To overcome this there is some
  temporary code in G4VViewer::NeedKernelVisit which marks *all*
  viewers to force a rebuild.  To see the symptoms, comment out that
  temporary code and issue these commands:
    /vis/verbose c
    /control/verbose 2
    /vis/scene/create
    /vis/scene/add/volume
    /vis/sceneHandler/create OGLSX
    /vis/viewer/create ! ! 1
    /run/beamOn
    /vis/viewer/create ! ! 1
    /vis/viewer/select viewer-0
    /vis/viewer/viewpointThetaPhi 20 20
    /vis/viewer/select viewer-1
    /vis/viewer/viewpointThetaPhi 40 40
    /vis/viewer/set/style surface
    /vis/viewer/refresh
    /vis/viewer/select viewer-0
    /vis/viewer/refresh
    /vis/viewer/select viewer-1
    /vis/viewer/set/style wireframe
    /vis/scene/notifyHandlers
  You may have to do this too:
    /vis/viewer/select viewer-0
    /vis/scene/notifyHandlers
  One of the viewers is empty.  Curious!!

9th August 2001  John Allison  (vis-V03-02-10-00)
- Implemented G4OpenGLStoredSceneHandler::ClearTransientStore()
- Removed G4OpenGLSceneHandler::AddPrimitive (const G4Polymarker&) (it only
  invoked G4VSceneHandler::AddPrimitive (const G4Polymarker&) which is
  picked up by inheritance anyway.
- Removed lots of unnecessary header files from G4OpenGLStoredSceneHandler.cc.
- Corrected order of calling base class functions in
  G4OpenGLStoredSceneHandler::Begin/EndModeling.

24th July 2001  John Allison  (vis-V03-02-06)
- G4OpenGLSceneHandler::AddPrimitive (const G4Text&) handles transformation.

14th July 2001  John Allison (opengl-V03-02-00)
- Fixed crash in optimised mode: added Initialise() to viewers so
  that windows are opened after viewers are fully constructed.

2nd April 2001  John Allison (opengl-V03-00-01 wrt vis-V03-00-09)
- Tidied G4OpenGLXmViewer callback code.  Removed superfluous header files.

7th March 2001  John Allison
- Changed char* to const char* in many places and that gave problems in
  calls to Xt and Xm.  Hope all's OK.  Differences:
    cvs diff -r vis-V03-00-06 vis-V03-00-07

25th January 2001  John Allison  (opengl-V03-00-00)
- Implemented running re-calculation of up-vector in the case of "object
  rotation" (lights move with camera) to prevent "flipping" of view when
  camera passes through up-vector.  Note that the default is "camera
  rotation" (lights do not move with camera, i.e., remain fixed relative
  to object) so the default is that this "flipping" can happen.  To set
  "object rotation" (lights move with camera) use
  /vis/lights/move_with_camera true (soon to be
  /vis/viewer/set/lights move-with-camera) or click "Object" radio button
  on Rotation Panel in OpenGLXm mode.
- Changed some objects to references for efficiency.  E.g.:
  const G4Vector3D& vp = pView->fVP.GetViewpointDirection ().unit ();

22nd May 2000  John Allison  (opengl-V01-01-00)
- Fixed slow response of 2nd window of OpenGLXm.  Worked around Mesa bug
  by sharing static visuals in G4OpenGLXViewer (Guy Barrand):
    static XVisualInfo* vi_single_buffer;
    static XVisualInfo* vi_double_buffer;
- Removed ChooseVisual from G4OpenGLXmViewer.cc - done in base class
  G4OpenGLXViewer.
- Protected double deletion of window in destructors of G4OpenGLXmViewer
  and G4OpenGLXViewer (Guy Barrand).
- Changed requested bits per colour to r,g,b = 1,1,1 in G4OpenGLViewer.cc.
- Corrected order of CreateMainWindow() and InitializeGLView() in X*Viewer
  constructors.
