//
// ********************************************************************
// * License and Disclaimer                                           *
// *                                                                  *
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// * the Geant4 Collaboration.  It is provided  under  the terms  and *
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// * institutes,nor the agencies providing financial support for this *
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// * technical work of the GEANT4 collaboration.                      *
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// ********************************************************************
//
//
// $Id$
//
// 
// Andrew Walkden  10th February 1997
// OpenGL stored scene - creates OpenGL display lists.

#ifdef G4VIS_BUILD_OPENGL_DRIVER

// Included here - problems with HP compiler if not before other includes?
#include "G4NURBS.hh"

// Here follows a special for Mesa, the OpenGL emulator.  Does not affect
// other OpenGL's, as far as I'm aware.   John Allison 18/9/96.
#define CENTERLINE_CLPP  /* CenterLine C++ workaround: */
// Also seems to be required for HP's CC and AIX xlC, at least.

#include "G4OpenGLStoredSceneHandler.hh"

#include "G4PhysicalVolumeModel.hh"
#include "G4LogicalVolumeModel.hh"
#include "G4VPhysicalVolume.hh"
#include "G4LogicalVolume.hh"
#include "G4Polyline.hh"
#include "G4Polymarker.hh"
#include "G4Text.hh"
#include "G4Circle.hh"
#include "G4Square.hh"
#include "G4Polyhedron.hh"
#include "G4AttHolder.hh"
#include "G4OpenGLTransform3D.hh"
#include "G4OpenGLViewer.hh"
#include "G4AttHolder.hh"

#include <typeinfo>

G4OpenGLStoredSceneHandler::PO::PO():
  fDisplayListId(0),
  fPickName(0),
  fpG4TextPlus(0),
  fMarkerOrPolyline(false)
{}

G4OpenGLStoredSceneHandler::PO::PO(const G4OpenGLStoredSceneHandler::PO& po):
  fDisplayListId(po.fDisplayListId),
  fTransform(po.fTransform),
  fPickName(po.fPickName),
  fColour(po.fColour),
  fpG4TextPlus(po.fpG4TextPlus? new G4TextPlus(*po.fpG4TextPlus): 0),
  fMarkerOrPolyline(po.fMarkerOrPolyline)
{}

G4OpenGLStoredSceneHandler::PO::PO(G4int id, const G4Transform3D& tr):
  fDisplayListId(id),
  fTransform(tr),
  fPickName(0),
  fpG4TextPlus(0),
  fMarkerOrPolyline(false)
{}

G4OpenGLStoredSceneHandler::PO::~PO()
{
  delete fpG4TextPlus;
}

G4OpenGLStoredSceneHandler::PO& G4OpenGLStoredSceneHandler::PO::operator=
  (const G4OpenGLStoredSceneHandler::PO& rhs)
{
  if (&rhs == this) return *this;
  fDisplayListId = rhs.fDisplayListId;
  fTransform = rhs.fTransform;
  fPickName = rhs.fPickName;
  fColour = rhs.fColour;
  fpG4TextPlus = rhs.fpG4TextPlus? new G4TextPlus(*rhs.fpG4TextPlus): 0;
  fMarkerOrPolyline = rhs.fMarkerOrPolyline;
  return *this;
}

G4OpenGLStoredSceneHandler::TO::TO():
  fDisplayListId(0),
  fPickName(0),
  fStartTime(-DBL_MAX),
  fEndTime(DBL_MAX),
  fpG4TextPlus(0),
  fMarkerOrPolyline(false)
{}

G4OpenGLStoredSceneHandler::TO::TO(const G4OpenGLStoredSceneHandler::TO& to):
  fDisplayListId(to.fDisplayListId),
  fTransform(to.fTransform),
  fPickName(to.fPickName),
  fStartTime(to.fStartTime),
  fEndTime(to.fEndTime),
  fColour(to.fColour),
  fpG4TextPlus(to.fpG4TextPlus? new G4TextPlus(*to.fpG4TextPlus): 0),
  fMarkerOrPolyline(to.fMarkerOrPolyline)
{}

G4OpenGLStoredSceneHandler::TO::TO(G4int id, const G4Transform3D& tr):
  fDisplayListId(id),
  fTransform(tr),
  fPickName(0),
  fStartTime(-DBL_MAX),
  fEndTime(DBL_MAX),
  fpG4TextPlus(0),
  fMarkerOrPolyline(false)
{}

G4OpenGLStoredSceneHandler::TO::~TO()
{
  delete fpG4TextPlus;
}

G4OpenGLStoredSceneHandler::TO& G4OpenGLStoredSceneHandler::TO::operator=
  (const G4OpenGLStoredSceneHandler::TO& rhs)
{
  if (&rhs == this) return *this;
  fDisplayListId = rhs.fDisplayListId;
  fTransform = rhs.fTransform;
  fPickName = rhs.fPickName;
  fStartTime = rhs.fStartTime;
  fEndTime = rhs.fEndTime;
  fColour = rhs.fColour;
  fpG4TextPlus = rhs.fpG4TextPlus? new G4TextPlus(*rhs.fpG4TextPlus): 0;
  fMarkerOrPolyline = rhs.fMarkerOrPolyline;
  return *this;
}

G4OpenGLStoredSceneHandler::G4OpenGLStoredSceneHandler
(G4VGraphicsSystem& system,
 const G4String& name):
G4OpenGLSceneHandler (system, fSceneIdCount++, name),
fTopPODL (0)
{}

G4OpenGLStoredSceneHandler::~G4OpenGLStoredSceneHandler ()
{}

void G4OpenGLStoredSceneHandler::BeginPrimitives
(const G4Transform3D& objectTransformation)
{  
  G4OpenGLSceneHandler::BeginPrimitives (objectTransformation);
  if (fReadyForTransients) glDrawBuffer (GL_FRONT);
  // Display list setup moved to AddPrimitivePreamble.  See notes there.
}

void G4OpenGLStoredSceneHandler::EndPrimitives ()
{
  // See all primitives immediately...  At least soon...
  ScaledFlush();
  glDrawBuffer (GL_BACK);
  G4OpenGLSceneHandler::EndPrimitives ();
}

void G4OpenGLStoredSceneHandler::BeginPrimitives2D
(const G4Transform3D& objectTransformation)
{
  G4OpenGLSceneHandler::BeginPrimitives2D(objectTransformation);
  if (fReadyForTransients) glDrawBuffer (GL_FRONT);
}

void G4OpenGLStoredSceneHandler::EndPrimitives2D ()
{
  // See all primitives immediately...  At least soon...
  ScaledFlush();
  glDrawBuffer (GL_BACK);
  G4OpenGLSceneHandler::EndPrimitives2D ();
}

G4bool G4OpenGLStoredSceneHandler::AddPrimitivePreamble(const G4Visible& visible)
{
  const G4Colour& c = GetColour (visible);
  G4double opacity = c.GetAlpha ();

  G4bool transparency_enabled = true;
  G4bool isMarkerNotHidden = true;
  G4OpenGLViewer* pViewer = dynamic_cast<G4OpenGLViewer*>(fpViewer);
  if (pViewer) {
    transparency_enabled = pViewer->transparency_enabled;
    isMarkerNotHidden = pViewer->fVP.IsMarkerNotHidden();
  }
  
  G4bool isMarker = false;
  try {
    (void) dynamic_cast<const G4VMarker&>(visible);
    isMarker = true;
  }
  catch (std::bad_cast) {}
  
  G4bool isPolyline = false;
  try {
    (void) dynamic_cast<const G4Polyline&>(visible);
    isPolyline = true;
  }
  catch (std::bad_cast) {}
  
  G4bool isTransparent = opacity < 1.;
  G4bool isMarkerOrPolyline = isMarker || isPolyline;
  G4bool treatAsTransparent = transparency_enabled && isTransparent;
  G4bool treatAsNotHidden = isMarkerNotHidden && isMarkerOrPolyline;
  
  if (fProcessing2D) glDisable (GL_DEPTH_TEST);
  else {
    if (isMarkerOrPolyline && isMarkerNotHidden)
      glDisable (GL_DEPTH_TEST);
    else {glEnable (GL_DEPTH_TEST); glDepthFunc (GL_LEQUAL);}
  }

  if (fThreePassCapable) {
    
    // Ensure transparent objects are drawn opaque ones and before
    // non-hidden markers.  The problem of blending/transparency/alpha
    // is quite a tricky one - see History of opengl-V07-01-01/2/3.
    if (!(fSecondPassForTransparency || fThirdPassForNonHiddenMarkers)) {
      // First pass...
      if (treatAsTransparent) {  // Request pass for transparent objects...
        fSecondPassForTransparencyRequested = true;
      }
      if (treatAsNotHidden) {    // Request pass for non-hidden markers...
        fThirdPassForNonHiddenMarkersRequested = true;
      }
      // On first pass, transparent objects and non-hidden markers are not drawn...
      if (treatAsTransparent || treatAsNotHidden) {
        return false;  // No further processing.
      }
    }
    
    // On second pass, only transparent objects are drawn...
    if (fSecondPassForTransparency) {
      if (!treatAsTransparent) {
        return false;  // No further processing.
      }
    }
    
    // On third pass, only non-hidden markers are drawn...
    if (fThirdPassForNonHiddenMarkers) {
      if (!treatAsNotHidden) {
        return false;  // No further processing.
        
      }
    }
  }  // fThreePassCapable
  
  // Loads G4Atts for picking...
  G4bool isPicking = false;
  if (fpViewer->GetViewParameters().IsPicking()) {
    isPicking = true;
    glLoadName(++fPickName);
    G4AttHolder* holder = new G4AttHolder;
    LoadAtts(visible, holder);
    fPickMap[fPickName] = holder;
  }
  
  // Can we re-use a display list?
  const G4VSolid* pSolid = 0;
  G4PhysicalVolumeModel* pPVModel =
  dynamic_cast<G4PhysicalVolumeModel*>(fpModel);
  if (fpViewer->GetViewParameters().GetVisAttributesModifiers().size())
    // Touchables have been modified - don't risk re-using display list.
    goto end_of_display_list_reuse_test;
  if (pPVModel) {
    // Check that it isn't a G4LogicalVolumeModel (which is a sub-class of
    // G4PhysicalVolumeModel).
    G4LogicalVolumeModel* pLVModel =
    dynamic_cast<G4LogicalVolumeModel*>(pPVModel);
    if (pLVModel)
      // Logical volume model - don't re-use.
      goto end_of_display_list_reuse_test;
    if (pViewer->fVP.IsSection() || pViewer->fVP.IsCutaway())
      // sections and cutaways generate unique views of each model instance
      goto end_of_display_list_reuse_test;
    // If part of the geometry hierarchy, i.e., from a
    // G4PhysicalVolumeModel, check if a display list already exists for
    // this solid, re-use it if possible.  We could be smarter, and
    // recognise repeated branches of the geometry hierarchy, for
    // example.  But this algorithm should be secure, I think...
    pSolid = pPVModel->GetCurrentPV()->GetLogicalVolume()->GetSolid();
    EAxis axis = kRho;
    G4VPhysicalVolume* pCurrentPV = pPVModel->GetCurrentPV();
    if (pCurrentPV -> IsReplicated ()) {
      G4int nReplicas;
      G4double width;
      G4double offset;
      G4bool consuming;
      pCurrentPV->GetReplicationData(axis,nReplicas,width,offset,consuming);
    }
    // Provided it is not parametrised (because if so, the
    // solid's parameters might have been changed)...
    if (!(pCurrentPV -> IsParameterised ()) &&
        // Provided it is not replicated radially (because if so, the
        // solid's parameters will have been changed)...
        !(pCurrentPV -> IsReplicated () && axis == kRho) &&
        // ...and if the solid has already been rendered...
        (fSolidMap.find (pSolid) != fSolidMap.end ())) {
      fDisplayListId = fSolidMap [pSolid];
      PO po(fDisplayListId,fObjectTransformation);
      if (isPicking) po.fPickName = fPickName;
      po.fColour = c;
      po.fMarkerOrPolyline = isMarkerOrPolyline;
      fPOList.push_back(po);
      // No need to test if gl commands are used (result of
      // ExtraPOProcessing) because we have already decided they will
      // not, at least not here.  Also, pass a dummy G4Visible since
      // not relevant for G4PhysicalVolumeModel.
      (void) ExtraPOProcessing(G4Visible(), fPOList.size() - 1);
      return false;  // No further processing.
    }
  }
end_of_display_list_reuse_test:

  // Because of our need to control colour of transients (display by
  // time fading), display lists may only cover a single primitive.
  // So display list setup is here.
  
  if (fMemoryForDisplayLists) {
    fDisplayListId = glGenLists (1);
    if (glGetError() == GL_OUT_OF_MEMORY ||
	fDisplayListId > fDisplayListLimit) {
      G4cout <<
      "********************* WARNING! ********************"
      "\n*  Display list limit reached in OpenGL."
      "\n*  Continuing drawing WITHOUT STORING. Scene only partially refreshable."
      "\n*  Current limit: " << fDisplayListLimit <<
      ".  Change with \"/vis/ogl/set/displayListLimit\"."
      "\n***************************************************"
      << G4endl;
      fMemoryForDisplayLists = false;
    }
  }
  
  if (pSolid) fSolidMap [pSolid] = fDisplayListId;

  if (fMemoryForDisplayLists) {
    if (fReadyForTransients) {
      TO to(fDisplayListId, fObjectTransformation);
      if (isPicking) to.fPickName = fPickName;
      to.fColour = c;
      const G4VisAttributes* pVA =
	fpViewer->GetApplicableVisAttributes(visible.GetVisAttributes());
      to.fStartTime = pVA->GetStartTime();
      to.fEndTime = pVA->GetEndTime();
      to.fMarkerOrPolyline = isMarkerOrPolyline;
      fTOList.push_back(to);
      // For transient objects, colour, transformation, are kept in
      // the TO, so should *not* be in the display list.  As mentioned
      // above, in some cases (display-by-time fading) we need to have
      // independent control of colour.  But for now transform and set
      // colour for immediate display.
      glPushMatrix();
      G4OpenGLTransform3D oglt (fObjectTransformation);
      glMultMatrixd (oglt.GetGLMatrix ());
      if (transparency_enabled) {
        glColor4d(c.GetRed(),c.GetGreen(),c.GetBlue(),c.GetAlpha());
      } else {
        glColor3d(c.GetRed(),c.GetGreen(),c.GetBlue());
      }
      (void) ExtraTOProcessing(visible, fTOList.size() - 1);
      // Ignore return value of the above.  If this visible does not use
      // gl commands, a display list is created that is empty and not
      // used.
      glNewList (fDisplayListId, GL_COMPILE_AND_EXECUTE);
    } else {
      PO po(fDisplayListId, fObjectTransformation);
      if (isPicking) po.fPickName = fPickName;
      po.fColour = c;
      po.fMarkerOrPolyline = isMarkerOrPolyline;
      fPOList.push_back(po);
      // For permanent objects, colour is kept in the PO, so should
      // *not* be in the display list.  This is so that sub-classes
      // may implement colour modifications according to their own
      // criteria, e.g., scen tree slider in Qt.  But for now set
      // colour for immediate display.
      if (transparency_enabled) {
        glColor4d(c.GetRed(),c.GetGreen(),c.GetBlue(),c.GetAlpha());
      } else {
        glColor3d(c.GetRed(),c.GetGreen(),c.GetBlue());
      }
      G4bool usesGLCommands = ExtraPOProcessing(visible, fPOList.size() - 1);
      // Transients are displayed as they come (GL_COMPILE_AND_EXECUTE
      // above) but persistents are compiled into display lists
      // (GL_COMPILE only) and then drawn from the display lists with
      // their fObjectTransformation as stored in fPOList.  Thus,
      // there is no need to do glMultMatrixd here.  If
      // ExtraPOProcessing says the visible object does not use gl
      // commands, simply return and abandon further processing.  It
      // is assumed that all relevant information is kept in the
      // POList.
      if (!usesGLCommands) return false;
      glNewList (fDisplayListId, GL_COMPILE);
    }
  } else {  // Out of memory (or being used when display lists not required).
    glDrawBuffer (GL_FRONT);
    glPushMatrix();
    G4OpenGLTransform3D oglt (fObjectTransformation);
    glMultMatrixd (oglt.GetGLMatrix ());
    if (transparency_enabled) {
      glColor4d(c.GetRed(),c.GetGreen(),c.GetBlue(),c.GetAlpha());
    } else {
      glColor3d(c.GetRed(),c.GetGreen(),c.GetBlue());
    }
  }

  if (fProcessing2D) {
    // Push current 3D world matrices and load identity to define screen
    // coordinates...
    glMatrixMode (GL_PROJECTION);
    glPushMatrix();
    glLoadIdentity();
    glOrtho (-1., 1., -1., 1., -G4OPENGL_FLT_BIG, G4OPENGL_FLT_BIG);
    glMatrixMode (GL_MODELVIEW);
    glPushMatrix();
    glLoadIdentity();
    G4OpenGLTransform3D oglt (fObjectTransformation);
    glMultMatrixd (oglt.GetGLMatrix ());
    glDisable(GL_DEPTH_TEST);  // But see parent scene handler!!  In
    glDisable (GL_LIGHTING);   // some cases, we need to re-iterate this.
  }

  return true;
}

void G4OpenGLStoredSceneHandler::AddPrimitivePostamble()
{
  if (fProcessing2D) {
    // Pop current 3D world matrices back again...
    glMatrixMode (GL_PROJECTION);
    glPopMatrix();
    glMatrixMode (GL_MODELVIEW);
    glPopMatrix();
  }

  //  if ((glGetError() == GL_TABLE_TOO_LARGE) || (glGetError() == GL_OUT_OF_MEMORY)) {  // Could close?
  if (glGetError() == GL_OUT_OF_MEMORY) {  // Could close?
    G4cout <<
      "ERROR: G4OpenGLStoredSceneHandler::AddPrimitivePostamble: Failure"
      "  to allocate display List for fTopPODL - try OpenGL Immediated mode."
           << G4endl;
  }
  if (fMemoryForDisplayLists) {
    glEndList();
    if (glGetError() == GL_OUT_OF_MEMORY) {  // Could close?
      G4cout <<
        "ERROR: G4OpenGLStoredSceneHandler::AddPrimitivePostamble: Failure"
	"  to allocate display List for fTopPODL - try OpenGL Immediated mode."
             << G4endl;
    }
  }
  if (fReadyForTransients || !fMemoryForDisplayLists) {
    glPopMatrix();
  }
}

void G4OpenGLStoredSceneHandler::AddPrimitive (const G4Polyline& polyline)
{
  G4bool furtherprocessing = AddPrimitivePreamble(polyline);
  if (furtherprocessing) {
    G4OpenGLSceneHandler::AddPrimitive(polyline);
    AddPrimitivePostamble();
  }
}

void G4OpenGLStoredSceneHandler::AddPrimitive (const G4Polymarker& polymarker)
{
  G4bool furtherprocessing = AddPrimitivePreamble(polymarker);
  if (furtherprocessing) {
    G4OpenGLSceneHandler::AddPrimitive(polymarker);
    AddPrimitivePostamble();
  }
}

void G4OpenGLStoredSceneHandler::AddPrimitive (const G4Text& text)
{
  // Note: colour is still handled in
  // G4OpenGLSceneHandler::AddPrimitive(const G4Text&), so it still
  // gets into the display list
  G4bool furtherprocessing = AddPrimitivePreamble(text);
  if (furtherprocessing) {
    G4OpenGLSceneHandler::AddPrimitive(text);
    AddPrimitivePostamble();
  }
}

void G4OpenGLStoredSceneHandler::AddPrimitive (const G4Circle& circle)
{
  G4bool furtherprocessing = AddPrimitivePreamble(circle);
  if (furtherprocessing) {
    G4OpenGLSceneHandler::AddPrimitive(circle);
    AddPrimitivePostamble();
  }
}

void G4OpenGLStoredSceneHandler::AddPrimitive (const G4Square& square)
{
  G4bool furtherprocessing = AddPrimitivePreamble(square);
  if (furtherprocessing) {
    G4OpenGLSceneHandler::AddPrimitive(square);
    AddPrimitivePostamble();
  }
}

void G4OpenGLStoredSceneHandler::AddPrimitive (const G4Scale& scale)
{
  // Let base class split into primitives.
  G4OpenGLSceneHandler::AddPrimitive(scale);
}

void G4OpenGLStoredSceneHandler::AddPrimitive (const G4Polyhedron& polyhedron)
{
  // Note: colour is still handled in
  // G4OpenGLSceneHandler::AddPrimitive(const G4Polyhedron&), so it still
  // gets into the display list
  G4bool furtherprocessing = AddPrimitivePreamble(polyhedron);
  if (furtherprocessing) {
    G4OpenGLSceneHandler::AddPrimitive(polyhedron);
    AddPrimitivePostamble();
  }
}

void G4OpenGLStoredSceneHandler::AddPrimitive (const G4NURBS& nurbs)
{
  // Note: colour is still handled in
  // G4OpenGLSceneHandler::AddPrimitive(const G4NURBS&), so it still
  // gets into the display list
  G4bool furtherprocessing = AddPrimitivePreamble(nurbs);
  if (furtherprocessing) {
    G4OpenGLSceneHandler::AddPrimitive(nurbs);
    AddPrimitivePostamble();
  }
}

void G4OpenGLStoredSceneHandler::BeginModeling () {
  G4VSceneHandler::BeginModeling();
  /* Debug...
  fDisplayListId = glGenLists (1);
  G4cout << "OGL::fDisplayListId (start): " << fDisplayListId << G4endl;
  */
}

void G4OpenGLStoredSceneHandler::EndModeling () {
  // Make a List which calls the other lists.
  fTopPODL = glGenLists (1);
  if (glGetError() == GL_OUT_OF_MEMORY) {  // Could pre-allocate?
    G4cout <<
      "ERROR: G4OpenGLStoredSceneHandler::EndModeling: Failure to allocate"
      "  display List for fTopPODL - try OpenGL Immediated mode."
	   << G4endl;
  } else {

    glNewList (fTopPODL, GL_COMPILE); {
      for (size_t i = 0; i < fPOList.size (); i++) {
	glPushMatrix();
	G4OpenGLTransform3D oglt (fPOList[i].fTransform);
	glMultMatrixd (oglt.GetGLMatrix ());
	if (fpViewer->GetViewParameters().IsPicking())
	  glLoadName(fPOList[i].fPickName);
	glCallList (fPOList[i].fDisplayListId);
	glPopMatrix();
      }
    }
    glEndList ();

    if (glGetError() == GL_OUT_OF_MEMORY) {  // Could close?
      G4cout <<
        "ERROR: G4OpenGLStoredSceneHandler::EndModeling: Failure to allocate"
        "  display List for fTopPODL - try OpenGL Immediated mode."
             << G4endl;
    }
  }

  G4VSceneHandler::EndModeling ();
}

void G4OpenGLStoredSceneHandler::ClearStore () {

  //G4cout << "G4OpenGLStoredSceneHandler::ClearStore" << G4endl;

  G4VSceneHandler::ClearStore ();  // Sets need kernel visit, etc.

  // Delete OpenGL permanent display lists.
  for (size_t i = 0; i < fPOList.size (); i++)
    glDeleteLists (fPOList[i].fDisplayListId, 1);
  if (fTopPODL) glDeleteLists (fTopPODL, 1);
  fTopPODL = 0;

  // Clear other lists, dictionary, etc.
  fPOList.clear ();
  fSolidMap.clear ();
  ClearAndDestroyAtts();

  // ...and clear transient store...
  for (size_t i = 0; i < fTOList.size (); i++)
    glDeleteLists(fTOList[i].fDisplayListId, 1);
  fTOList.clear ();

  fMemoryForDisplayLists = true;
}

void G4OpenGLStoredSceneHandler::ClearTransientStore ()
{
  //G4cout << "G4OpenGLStoredSceneHandler::ClearTransientStore" << G4endl;

  // Delete OpenGL transient display lists and Transient Objects themselves.
  for (size_t i = 0; i < fTOList.size (); i++)
    glDeleteLists(fTOList[i].fDisplayListId, 1);
  fTOList.clear ();

  fMemoryForDisplayLists = true;

  // Redraw the scene ready for the next event.
  if (fpViewer) {
    fpViewer -> SetView ();
    fpViewer -> ClearView ();
    fpViewer -> DrawView ();
  }
}

G4int G4OpenGLStoredSceneHandler::fSceneIdCount = 0;

G4int  G4OpenGLStoredSceneHandler::fDisplayListId = 0;
G4bool G4OpenGLStoredSceneHandler::fMemoryForDisplayLists = true;
G4int  G4OpenGLStoredSceneHandler::fDisplayListLimit = 50000;

#endif