diff --git a/Core/Code/Rendering/mitkGLMapper.cpp b/Core/Code/Rendering/mitkGLMapper.cpp
index e383a306d4..c0440dcacf 100644
--- a/Core/Code/Rendering/mitkGLMapper.cpp
+++ b/Core/Code/Rendering/mitkGLMapper.cpp
@@ -1,56 +1,60 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 
 #include "mitkGL.h"
 #include "mitkGLMapper.h"
 
 
 mitk::GLMapper::GLMapper()
 {
 }
 
 mitk::GLMapper::~GLMapper()
 {
 }
 
 void mitk::GLMapper::MitkRender(mitk::BaseRenderer* renderer, mitk::VtkPropRenderer::RenderType /* type */)
 {
   bool visible = true;
 
   GetDataNode()->GetVisibility(visible, renderer, "visible");
 
   if(!visible)
     return;
 
-  Paint(renderer);
+  // the if-condition ensures that Paint(renderer) is only called once, otherwise it will be called four times
+  // it does not mean that OpenGL renders only an opaque scene
+  if(type == mitk::VtkPropRenderer::Opaque)
+    Paint(renderer);
+
 }
 
 bool mitk::GLMapper::IsVtkBased() const
 {
   return false;
 }
 
 void mitk::GLMapper::ApplyColorAndOpacityProperties(mitk::BaseRenderer* renderer, vtkActor* /*actor*/)
 {
     float rgba[4]={1.0f,1.0f,1.0f,1.0f};
     // check for color prop and use it for rendering if it exists
     GetDataNode()->GetColor(rgba, renderer, "color");
     // check for opacity prop and use it for rendering if it exists
     GetDataNode()->GetOpacity(rgba[3], renderer, "opacity");
 
     glColor4fv(rgba);
 }
diff --git a/Core/Code/Rendering/mitkVtkPropRenderer.cpp b/Core/Code/Rendering/mitkVtkPropRenderer.cpp
index 59fc8efcef..22e1a83215 100644
--- a/Core/Code/Rendering/mitkVtkPropRenderer.cpp
+++ b/Core/Code/Rendering/mitkVtkPropRenderer.cpp
@@ -1,926 +1,927 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 
 #include "mitkVtkPropRenderer.h"
 
 // MAPPERS
 #include "mitkMapper.h"
 #include "mitkImageVtkMapper2D.h"
 #include "mitkVtkMapper.h"
 #include "mitkGLMapper.h"
 #include "mitkGeometry2DDataVtkMapper3D.h"
 #include "mitkPointSetGLMapper2D.h"
 
 #include "mitkImageSliceSelector.h"
 #include "mitkRenderingManager.h"
 #include "mitkGL.h"
 #include "mitkGeometry3D.h"
 #include "mitkDisplayGeometry.h"
 #include "mitkLevelWindow.h"
 #include "mitkCameraController.h"
 #include "mitkVtkInteractorCameraController.h"
 #include "mitkPlaneGeometry.h"
 #include "mitkProperties.h"
 #include "mitkSurface.h"
 #include "mitkNodePredicateDataType.h"
 #include "mitkVtkInteractorStyle.h"
 
 // VTK
 #include <vtkRenderer.h>
 #include <vtkRendererCollection.h>
 #include <vtkLight.h>
 #include <vtkLightKit.h>
 #include <vtkRenderWindow.h>
 #include <vtkLinearTransform.h>
 #include <vtkCamera.h>
 #include <vtkWorldPointPicker.h>
 #include <vtkPointPicker.h>
 #include <vtkCellPicker.h>
 #include <vtkTextActor.h>
 #include <vtkTextProperty.h>
 #include <vtkProp.h>
 #include <vtkAssemblyPath.h>
 #include <vtkAssemblyNode.h>
 #include <vtkMapper.h>
 #include <vtkSmartPointer.h>
 #include <vtkTransform.h>
 #include <vtkInteractorStyleTrackballCamera.h>
 
 
 mitk::VtkPropRenderer::VtkPropRenderer( const char* name, vtkRenderWindow * renWin, mitk::RenderingManager* rm )
   : BaseRenderer(name,renWin, rm),
   m_VtkMapperPresent(false),
   m_CameraInitializedForMapperID(0)
 {
   didCount=false;
 
   m_WorldPointPicker = vtkWorldPointPicker::New();
 
   m_PointPicker = vtkPointPicker::New();
   m_PointPicker->SetTolerance( 0.0025 );
 
   m_CellPicker = vtkCellPicker::New();
   m_CellPicker->SetTolerance( 0.0025 );
 
   mitk::Geometry2DDataVtkMapper3D::Pointer geometryMapper = mitk::Geometry2DDataVtkMapper3D::New();
   m_CurrentWorldGeometry2DMapper = geometryMapper;
   m_CurrentWorldGeometry2DNode->SetMapper(2, geometryMapper);
 
   m_LightKit = vtkLightKit::New();
   m_LightKit->AddLightsToRenderer(m_VtkRenderer);
   m_PickingMode = WorldPointPicking;
 
   m_TextRenderer = vtkRenderer::New();
   m_TextRenderer->SetRenderWindow(renWin);
   m_TextRenderer->SetInteractive(0);
   m_TextRenderer->SetErase(0);
 }
 
 /*!
 \brief Destructs the VtkPropRenderer.
 */
 mitk::VtkPropRenderer::~VtkPropRenderer()
 {
   // Workaround for GLDisplayList Bug
   {
     m_MapperID=0;
     checkState();
   }
 
   if (m_LightKit != NULL)
     m_LightKit->Delete();
 
   if (m_VtkRenderer!=NULL)
   {
     m_CameraController = NULL;
 
     m_VtkRenderer->Delete();
 
     m_VtkRenderer = NULL;
   }
   else
     m_CameraController = NULL;
 
   if (m_WorldPointPicker != NULL)
     m_WorldPointPicker->Delete();
   if (m_PointPicker != NULL)
     m_PointPicker->Delete();
   if (m_CellPicker != NULL)
     m_CellPicker->Delete();
   if (m_TextRenderer != NULL)
     m_TextRenderer->Delete();
 }
 
 
 void mitk::VtkPropRenderer::SetDataStorage(  mitk::DataStorage* storage  )
 {
   if ( storage == NULL )
     return;
 
   BaseRenderer::SetDataStorage(storage);
 
   static_cast<mitk::Geometry2DDataVtkMapper3D*>(m_CurrentWorldGeometry2DMapper.GetPointer())->SetDataStorageForTexture( m_DataStorage.GetPointer() );
 
   // Compute the geometry from the current data tree bounds and set it as world geometry
   this->SetWorldGeometryToDataStorageBounds();
 }
 
 
 bool mitk::VtkPropRenderer::SetWorldGeometryToDataStorageBounds()
 {
   if ( m_DataStorage.IsNull() )
     return false;
 
   //initialize world geometry
   mitk::TimeSlicedGeometry::Pointer geometry = m_DataStorage->ComputeVisibleBoundingGeometry3D( NULL, "includeInBoundingBox" );
 
   if ( geometry.IsNull() )
     return false;
 
   this->SetWorldGeometry(geometry);
   //this->GetDisplayGeometry()->SetSizeInDisplayUnits( this->m_TextRenderer->GetRenderWindow()->GetSize()[0], this->m_TextRenderer->GetRenderWindow()->GetSize()[1] );
   this->GetDisplayGeometry()->Fit();
   this->GetVtkRenderer()->ResetCamera();
   this->Modified();
   return true;
 }
 
 
 /*!
 \brief
 
 Called by the vtkMitkRenderProp in order to start MITK rendering process.
 */
 int mitk::VtkPropRenderer::Render(mitk::VtkPropRenderer::RenderType type)
 {
 
   // Do we have objects to render?
   if ( this->GetEmptyWorldGeometry())
     return 0;
 
   if ( m_DataStorage.IsNull())
     return 0;
 
   // Update mappers and prepare mapper queue
   if (type == VtkPropRenderer::Opaque)
     this->PrepareMapperQueue();
 
   //go through the generated list and let the sorted mappers paint
   bool lastVtkBased = true;
   //bool sthVtkBased = false;
 
   for(MappersMapType::iterator it = m_MappersMap.begin(); it != m_MappersMap.end(); it++)
   {
     Mapper * mapper = (*it).second;
 
     VtkMapper* vtkmapper = dynamic_cast<VtkMapper*>(mapper);
 
     if(vtkmapper)
     {
       //sthVtkBased = true;
       if(!lastVtkBased)
       {
         Disable2DOpenGL();
         lastVtkBased = true;
       }
     }
     else
       if(lastVtkBased)
       {
       Enable2DOpenGL();
       lastVtkBased = false;
     }
 
   mapper->MitkRender(this, type);
 
   }
 
   if (lastVtkBased == false)
     Disable2DOpenGL();
 
   // Render text
   if (type == VtkPropRenderer::Overlay)
   {
     if (m_TextCollection.size() > 0)
     {
       for (TextMapType::iterator it = m_TextCollection.begin(); it != m_TextCollection.end() ; it++)
         m_TextRenderer->AddViewProp((*it).second);
       m_TextRenderer->Render();
     }
   }
   return 1;
 }
 
 /*!
 \brief PrepareMapperQueue iterates the datatree
 
 PrepareMapperQueue iterates the datatree in order to find mappers which shall be rendered. Also, it sortes the mappers wrt to their layer.
 */
 void mitk::VtkPropRenderer::PrepareMapperQueue()
 {
   // variable for counting LOD-enabled mappers
   m_NumberOfVisibleLODEnabledMappers = 0;
 
   // Do we have to update the mappers ?
   if ( m_LastUpdateTime < GetMTime() || m_LastUpdateTime < GetDisplayGeometry()->GetMTime() ) {
     Update();
   }
   else if (m_MapperID>=1 && m_MapperID < 6)
     Update();
 
   // remove all text properties before mappers will add new ones
   m_TextRenderer->RemoveAllViewProps();
 
   for ( unsigned int i=0; i<m_TextCollection.size(); i++ )
   {
     m_TextCollection[i]->Delete();
   }
   m_TextCollection.clear();
 
   // clear priority_queue
   m_MappersMap.clear();
 
   int mapperNo = 0;
 
   //DataStorage
   if( m_DataStorage.IsNull() )
     return;
 
   DataStorage::SetOfObjects::ConstPointer allObjects = m_DataStorage->GetAll();
 
   for (DataStorage::SetOfObjects::ConstIterator it = allObjects->Begin();  it != allObjects->End(); ++it)
   {
     DataNode::Pointer node = it->Value();
     if ( node.IsNull() )
       continue;
     mitk::Mapper::Pointer mapper = node->GetMapper(m_MapperID);
 
     if ( mapper.IsNull() )
       continue;
 
     bool visible = true;
     node->GetVisibility(visible, this, "visible");
 
     // The information about LOD-enabled mappers is required by RenderingManager
     if ( mapper->IsLODEnabled( this ) && visible )
     {
       ++m_NumberOfVisibleLODEnabledMappers;
     }
     // mapper without a layer property get layer number 1
     int layer = 1;
     node->GetIntProperty("layer", layer, this);
     int nr = (layer<<16) + mapperNo;
     m_MappersMap.insert( std::pair< int, Mapper * >( nr, mapper ) );
     mapperNo++;
   }
 }
 
 /*!
 \brief
 
 Enable2DOpenGL() and Disable2DOpenGL() are used to switch between 2D rendering (orthographic projection) and 3D rendering (perspective projection)
 */
 void mitk::VtkPropRenderer::Enable2DOpenGL()
 {
   GLint iViewport[4];
 
   // Get a copy of the viewport
   glGetIntegerv( GL_VIEWPORT, iViewport );
 
   // Save a copy of the projection matrix so that we can restore it
   // when it's time to do 3D rendering again.
   glMatrixMode( GL_PROJECTION );
   glPushMatrix();
   glLoadIdentity();
 
   // Set up the orthographic projection
   glOrtho(
       iViewport[0], iViewport[0]+iViewport[2],
       iViewport[1], iViewport[1]+iViewport[3],
       -1.0, 1.0
       );
   glMatrixMode( GL_MODELVIEW );
   glPushMatrix();
   glLoadIdentity();
 
   // Make sure depth testing and lighting are disabled for 2D rendering until
   // we are finished rendering in 2D
   glPushAttrib( GL_DEPTH_BUFFER_BIT | GL_LIGHTING_BIT );
   glDisable( GL_DEPTH_TEST );
   glDisable( GL_LIGHTING );
   // disable the texturing here so crosshair is painted in the correct colors
   // vtk will reenable texturing every time it is needed
   glDisable( GL_TEXTURE_1D );
   glDisable( GL_TEXTURE_2D );
+  glLineWidth(1.0);
 }
 
 /*!
 \brief Initialize the VtkPropRenderer
 
 Enable2DOpenGL() and Disable2DOpenGL() are used to switch between 2D rendering (orthographic projection) and 3D rendering (perspective projection)
 */
 void mitk::VtkPropRenderer::Disable2DOpenGL()
 {
   glPopAttrib();
   glMatrixMode( GL_PROJECTION );
   glPopMatrix();
   glMatrixMode( GL_MODELVIEW );
   glPopMatrix();
 }
 
 
 void mitk::VtkPropRenderer::Update(mitk::DataNode* datatreenode)
 {
   if(datatreenode!=NULL)
   {
     mitk::Mapper::Pointer mapper = datatreenode->GetMapper(m_MapperID);
     if(mapper.IsNotNull())
     {
       GLMapper* glmapper=dynamic_cast<GLMapper*>(mapper.GetPointer());
 
       if(GetDisplayGeometry()->IsValid())
       {
         if(glmapper != NULL)
         {
           glmapper->Update(this);
           m_VtkMapperPresent=false;
         }
         else
         {
           VtkMapper* vtkmapper=dynamic_cast<VtkMapper*>(mapper.GetPointer());
           if(vtkmapper != NULL)
           {
             vtkmapper->Update(this);
             vtkmapper->UpdateVtkTransform(this);
             m_VtkMapperPresent=true;
           }
         }
       }
     }
   }
 }
 
 
 void mitk::VtkPropRenderer::Update()
 {
   if( m_DataStorage.IsNull() )
     return;
 
   m_VtkMapperPresent = false;
   mitk::DataStorage::SetOfObjects::ConstPointer all = m_DataStorage->GetAll();
   for (mitk::DataStorage::SetOfObjects::ConstIterator it = all->Begin(); it != all->End(); ++it)
     Update(it->Value());
 
   Modified();
   m_LastUpdateTime = GetMTime();
 }
 
 
 /*!
 \brief
 
 This method is called from the two Constructors
 */
 void mitk::VtkPropRenderer::InitRenderer(vtkRenderWindow* renderWindow)
 {
   BaseRenderer::InitRenderer(renderWindow);
 
   if(renderWindow == NULL)
   {
     m_InitNeeded = false;
     m_ResizeNeeded = false;
     return;
   }
 
   m_InitNeeded = true;
   m_ResizeNeeded = true;
 
   m_LastUpdateTime = 0;
 
 }
 
 
 /*!
 \brief Resize the OpenGL Window
 */
 void mitk::VtkPropRenderer::Resize(int w, int h)
 {
   BaseRenderer::Resize(w, h);
   m_RenderingManager->RequestUpdate(this->GetRenderWindow());
 }
 
 
 void mitk::VtkPropRenderer::InitSize(int w, int h)
 {
   m_RenderWindow->SetSize(w,h);
   Superclass::InitSize(w, h);
   Modified();
   Update();
   if(m_VtkRenderer!=NULL)
   {
     int w=vtkObject::GetGlobalWarningDisplay();
     vtkObject::GlobalWarningDisplayOff();
     m_VtkRenderer->ResetCamera();
     vtkObject::SetGlobalWarningDisplay(w);
   }
 }
 
 
 void mitk::VtkPropRenderer::SetMapperID(const MapperSlotId mapperId)
 {
   if(m_MapperID != mapperId)
     Superclass::SetMapperID(mapperId);
 
   // Workaround for GL Displaylist Bug
   checkState();
 }
 
 
 /*!
 \brief Activates the current renderwindow.
 */
 void mitk::VtkPropRenderer::MakeCurrent()
 {
   if(m_RenderWindow!=NULL)
     m_RenderWindow->MakeCurrent();
 }
 
 
 void mitk::VtkPropRenderer::PickWorldPoint(const mitk::Point2D& displayPoint, mitk::Point3D& worldPoint) const
 {
   if(m_VtkMapperPresent)
   {
     //m_WorldPointPicker->SetTolerance (0.0001);
     switch ( m_PickingMode )
     {
     case (WorldPointPicking) :
       {
         m_WorldPointPicker->Pick(displayPoint[0], displayPoint[1], 0, m_VtkRenderer);
         vtk2itk(m_WorldPointPicker->GetPickPosition(), worldPoint);
         break;
       }
     case (PointPicking) :
       {
         // create a new vtkRenderer
         // give it all necessary information (camera position, etc.)
         // get all surfaces from datastorage, get actors from them
         // add all those actors to the new renderer
         // give this new renderer to pointpicker
         /*
        vtkRenderer* pickingRenderer = vtkRenderer::New();
        pickingRenderer->SetActiveCamera( );
 
        DataStorage* dataStorage = m_DataStorage;
        TNodePredicateDataType<Surface> isSurface;
 
        DataStorage::SetOfObjects::ConstPointer allSurfaces = dataStorage->GetSubset( isSurface );
        MITK_INFO << "in picking: got " << allSurfaces->size() << " surfaces." << std::endl;
 
        for (DataStorage::SetOfObjects::const_iterator iter = allSurfaces->begin();
             iter != allSurfaces->end();
             ++iter)
        {
          const DataNode* currentNode = *iter;
          VtkMapper3D* baseVtkMapper3D = dynamic_cast<VtkMapper3D*>( currentNode->GetMapper( BaseRenderer::Standard3D ) );
          if ( baseVtkMapper3D )
          {
            vtkActor* actor = dynamic_cast<vtkActor*>( baseVtkMapper3D->GetViewProp() );
            if (actor)
            {
              MITK_INFO << "a" << std::flush;
              pickingRenderer->AddActor( actor );
            }
          }
        }
 
        MITK_INFO << ";" << std::endl;
        */
         m_PointPicker->Pick(displayPoint[0], displayPoint[1], 0, m_VtkRenderer);
         vtk2itk(m_PointPicker->GetPickPosition(), worldPoint);
         break;
       }
     }
   }
   else
   {
     Superclass::PickWorldPoint(displayPoint, worldPoint);
   }
 }
 
 mitk::DataNode *
     mitk::VtkPropRenderer::PickObject( const Point2D &displayPosition, Point3D &worldPosition ) const
 {
   if ( m_VtkMapperPresent )
   {
     m_CellPicker->InitializePickList();
 
     // Iterate over all DataStorage objects to determine all vtkProps intended
     // for picking
     DataStorage::SetOfObjects::ConstPointer allObjects = m_DataStorage->GetAll();
     for ( DataStorage::SetOfObjects::ConstIterator it = allObjects->Begin();
     it != allObjects->End();
     ++it )
     {
       DataNode *node = it->Value();
       if ( node == NULL )
         continue;
 
       bool pickable = false;
       node->GetBoolProperty( "pickable", pickable );
       if ( !pickable )
         continue;
 
       VtkMapper *mapper = dynamic_cast < VtkMapper * >  ( node->GetMapper( m_MapperID ) );
       if ( mapper == NULL )
         continue;
 
       vtkProp *prop = mapper->GetVtkProp( (mitk::BaseRenderer *)this );
       if ( prop == NULL )
         continue;
 
       m_CellPicker->AddPickList( prop );
     }
 
 
     // Do the picking and retrieve the picked vtkProp (if any)
     m_CellPicker->PickFromListOn();
     m_CellPicker->Pick( displayPosition[0], displayPosition[1], 0.0, m_VtkRenderer );
     m_CellPicker->PickFromListOff();
 
     vtk2itk( m_CellPicker->GetPickPosition(), worldPosition );
     vtkProp *prop = m_CellPicker->GetViewProp();
 
     if ( prop == NULL )
     {
       return NULL;
     }
 
     // Iterate over all DataStorage objects to determine if the retrieved
     // vtkProp is owned by any associated mapper.
     for ( DataStorage::SetOfObjects::ConstIterator it = allObjects->Begin();
     it != allObjects->End();
     ++it)
     {
       DataNode::Pointer node = it->Value();
       if ( node.IsNull() )
         continue;
 
       mitk::Mapper * mapper = node->GetMapper( m_MapperID );
       if ( mapper == NULL)
         continue;
 
       mitk::VtkMapper * vtkmapper = dynamic_cast< VtkMapper * >(mapper);
 
       if(vtkmapper){
         //if vtk-based, then ...
        if ( vtkmapper->HasVtkProp( prop, const_cast< mitk::VtkPropRenderer * >( this ) ) )
        {
           return node;
        }
       }
     }
 
     return NULL;
   }
   else
   {
     return Superclass::PickObject( displayPosition, worldPosition );
   }
 };
 
 
 
 /*!
 \brief Writes some 2D text as overlay. Function returns an unique int Text_ID for each call, which can be used via the GetTextLabelProperty(int text_id) function
 in order to get a vtkTextProperty. This property enables the setup of font, font size, etc.
 */
 int mitk::VtkPropRenderer::WriteSimpleText(std::string text, double posX, double posY, double color1, double color2, double color3, float opacity)
 {
   if(text.size() > 0)
   {
     vtkTextActor* textActor = vtkTextActor::New();
 
     textActor->SetPosition(posX,posY);
     textActor->SetInput(text.c_str());
     textActor->GetTextProperty()->SetColor(color1, color2, color3); //TODO: Read color from node property
     textActor->GetTextProperty()->SetOpacity( opacity );
     int text_id = m_TextCollection.size();
     m_TextCollection.insert(TextMapType::value_type(text_id,textActor));
     return text_id;
   }
   return -1;
 }
 
 
 /*!
 \brief Can be used in order to get a vtkTextProperty for a specific text_id. This property enables the setup of font, font size, etc.
 */
 vtkTextProperty* mitk::VtkPropRenderer::GetTextLabelProperty(int text_id)
 {
   return this->m_TextCollection[text_id]->GetTextProperty();
 }
 
 
 void mitk::VtkPropRenderer::InitPathTraversal()
 {
   if (m_DataStorage.IsNotNull())
   {
     m_PickingObjects = m_DataStorage->GetAll();
     m_PickingObjectsIterator = m_PickingObjects->begin();
   }
 }
 
 
 vtkAssemblyPath* mitk::VtkPropRenderer::GetNextPath()
 {
   if (m_DataStorage.IsNull() )
   {
     return NULL;
   }
 
   if ( m_PickingObjectsIterator == m_PickingObjects->end() )
   {
     return NULL;
   }
 
   vtkAssemblyPath* returnPath = vtkAssemblyPath::New();
   //returnPath->Register(NULL);
 
   bool success = false;
 
   while (!success)
   {
     // loop until AddNode can be called successfully
     const DataNode* node = *m_PickingObjectsIterator;
     if (node)
     {
       Mapper* mapper = node->GetMapper( BaseRenderer::Standard3D );
       if (mapper)
       {
         VtkMapper* vtkmapper = dynamic_cast<VtkMapper*>( mapper );
         if (vtkmapper)
         {
           vtkProp* prop = vtkmapper->GetVtkProp(this);
           if ( prop && prop->GetVisibility() )
           {
             // add to assembly path
             returnPath->AddNode( prop, prop->GetMatrix() );
             success = true;
           }
         }
       }
     }
 
     ++m_PickingObjectsIterator;
 
     if ( m_PickingObjectsIterator == m_PickingObjects->end() ) break;
   }
 
   if ( success )
   {
     return returnPath;
   }
   else
   {
     return NULL;
   }
 }
 
 
 void mitk::VtkPropRenderer::ReleaseGraphicsResources(vtkWindow *renWin)
 {
   if( m_DataStorage.IsNull() )
     return;
 
   DataStorage::SetOfObjects::ConstPointer allObjects = m_DataStorage->GetAll();
   for (DataStorage::SetOfObjects::const_iterator iter = allObjects->begin(); iter != allObjects->end(); ++iter)
   {
     DataNode::Pointer node = *iter;
     if ( node.IsNull() )
       continue;
 
       Mapper * mapper = node->GetMapper(m_MapperID);
 
       if (mapper)
       {
         VtkMapper* vtkmapper = dynamic_cast<VtkMapper*>( mapper );
 
        if(vtkmapper)
          vtkmapper->ReleaseGraphicsResources(renWin);
       }
    }
 }
 
 
 const vtkWorldPointPicker *mitk::VtkPropRenderer::GetWorldPointPicker() const
 {
   return m_WorldPointPicker;
 }
 
 
 const vtkPointPicker *mitk::VtkPropRenderer::GetPointPicker() const
 {
   return m_PointPicker;
 }
 
 
 const vtkCellPicker *mitk::VtkPropRenderer::GetCellPicker() const
 {
   return m_CellPicker;
 }
 
 
 mitk::VtkPropRenderer::MappersMapType mitk::VtkPropRenderer::GetMappersMap() const
 {
   return m_MappersMap;
 }
 
 
 // Workaround for GL Displaylist bug
 
 static int glWorkAroundGlobalCount = 0;
 
 bool mitk::VtkPropRenderer::useImmediateModeRendering()
 {
   return glWorkAroundGlobalCount>1;
 }
 
 void mitk::VtkPropRenderer::checkState()
 {
   if (m_MapperID == Standard3D)
   {
     if (!didCount)
     {
       didCount = true;
       glWorkAroundGlobalCount++;
 
       if (glWorkAroundGlobalCount == 2)
       {
         MITK_INFO << "Multiple 3D Renderwindows active...: turning Immediate Rendering ON for legacy mappers";
         //          vtkMapper::GlobalImmediateModeRenderingOn();
       }
       //MITK_INFO << "GLOBAL 3D INCREASE " << glWorkAroundGlobalCount << "\n";
 
     }
   }
   else
   {
     if(didCount)
     {
       didCount=false;
       glWorkAroundGlobalCount--;
       if(glWorkAroundGlobalCount==1)
       {
         MITK_INFO << "Single 3D Renderwindow active...: turning Immediate Rendering OFF for legacy mappers";
         //        vtkMapper::GlobalImmediateModeRenderingOff();
       }
       //MITK_INFO << "GLOBAL 3D DECREASE " << glWorkAroundGlobalCount << "\n";
     }
   }
 }
 
 //### Contains all methods which are neceassry before each VTK Render() call
 void mitk::VtkPropRenderer::PrepareRender()
 {
   if ( this->GetMapperID() != m_CameraInitializedForMapperID )
   {
     Initialize2DvtkCamera(); //Set parallel projection etc.
   }
 
   AdjustCameraToScene(); //Prepare camera for 2D render windows
 }
 
 bool mitk::VtkPropRenderer::Initialize2DvtkCamera()
 {
   if ( this->GetMapperID() == Standard3D )
   {
     //activate parallel projection for 2D
     this->GetVtkRenderer()->GetActiveCamera()->SetParallelProjection(false);
     this->GetRenderWindow()->GetInteractor()->SetInteractorStyle( vtkInteractorStyleTrackballCamera::New() );
     m_CameraInitializedForMapperID = Standard3D;
   }
   else if( this->GetMapperID() == Standard2D)
   {
     //activate parallel projection for 2D
     this->GetVtkRenderer()->GetActiveCamera()->SetParallelProjection(true);
     //turn the light out in the scene in order to render correct grey values.
     //TODO Implement a property for light in the 2D render windows (in another method)
     this->GetVtkRenderer()->RemoveAllLights();
 
     this->GetRenderWindow()->GetInteractor()->SetInteractorStyle( mitkVtkInteractorStyle::New() );
 
     m_CameraInitializedForMapperID = Standard2D;
   }
   return true;
 }
 
 void mitk::VtkPropRenderer::AdjustCameraToScene(){
   if(this->GetMapperID() == Standard2D)
   {
     const mitk::DisplayGeometry* displayGeometry = this->GetDisplayGeometry();
 
     double objectHeightInMM = this->GetCurrentWorldGeometry2D()->GetExtentInMM(1);//the height of the current object slice in mm
     double displayHeightInMM = displayGeometry->GetSizeInMM()[1]; //the display height in mm (gets smaller when you zoom in)
     double zoomFactor = objectHeightInMM/displayHeightInMM; //displayGeometry->GetScaleFactorMMPerDisplayUnit()
     //determine how much of the object can be displayed
 
     Vector2D displayGeometryOriginInMM = displayGeometry->GetOriginInMM();  //top left of the render window (Origin)
     Vector2D displayGeometryCenterInMM = displayGeometryOriginInMM + displayGeometry->GetSizeInMM()*0.5; //center of the render window: (Origin + Size/2)
 
     //Scale the rendered object:
     //The image is scaled by a single factor, because in an orthographic projection sizes
     //are preserved (so you cannot scale X and Y axis with different parameters). The
     //parameter sets the size of the total display-volume. If you set this to the image
     //height, the image plus a border with the size of the image will be rendered.
     //Therefore, the size is imageHeightInMM / 2.
     this->GetVtkRenderer()->GetActiveCamera()->SetParallelScale(objectHeightInMM*0.5 );
     //zooming with the factor calculated by dividing displayHeight through imegeHeight. The factor is inverse, because the VTK zoom method is working inversely.
     this->GetVtkRenderer()->GetActiveCamera()->Zoom(zoomFactor);
 
     //the center of the view-plane
     double viewPlaneCenter[3];
     viewPlaneCenter[0] = displayGeometryCenterInMM[0];
     viewPlaneCenter[1] = displayGeometryCenterInMM[1];
     viewPlaneCenter[2] = 0.0; //the view-plane is located in the XY-plane with Z=0.0
 
     //define which direction is "up" for the ciamera (like default for vtk (0.0, 1.0, 0.0)
     double cameraUp[3];
     cameraUp[0] = 0.0;
     cameraUp[1] = 1.0;
     cameraUp[2] = 0.0;
 
     //the position of the camera (center[0], center[1], 900000)
     double cameraPosition[3];
     cameraPosition[0] = viewPlaneCenter[0];
     cameraPosition[1] = viewPlaneCenter[1];
     cameraPosition[2] = 900000.0; //Reason for 900000: VTK seems to calculate the clipping planes wrong for small values. See VTK bug (id #7823) in VTK bugtracker.
 
     //set the camera corresponding to the textured plane
     vtkSmartPointer<vtkCamera> camera = this->GetVtkRenderer()->GetActiveCamera();
     if (camera)
     {
       camera->SetPosition( cameraPosition ); //set the camera position on the textured plane normal (in our case this is the view plane normal)
       camera->SetFocalPoint( viewPlaneCenter ); //set the focal point to the center of the textured plane
       camera->SetViewUp( cameraUp ); //set the view-up for the camera
       //      double distance = sqrt((cameraPosition[2]-viewPlaneCenter[2])*(cameraPosition[2]-viewPlaneCenter[2]));
       //      camera->SetClippingRange(distance-50, distance+50); //Reason for huge range: VTK seems to calculate the clipping planes wrong for small values. See VTK bug (id #7823) in VTK bugtracker.
       camera->SetClippingRange(0.1, 1000000); //Reason for huge range: VTK seems to calculate the clipping planes wrong for small values. See VTK bug (id #7823) in VTK bugtracker.
     }
 
     const PlaneGeometry *planeGeometry = dynamic_cast< const PlaneGeometry * >( this->GetCurrentWorldGeometry2D() );
     if ( planeGeometry != NULL )
     {
       //Transform the camera to the current position (transveral, coronal and saggital plane).
       //This is necessary, because the SetUserTransform() method does not manipulate the vtkCamera.
       //(Without not all three planes would be visible).
       vtkSmartPointer<vtkTransform> trans = vtkSmartPointer<vtkTransform>::New();
       vtkSmartPointer<vtkMatrix4x4> matrix = vtkSmartPointer<vtkMatrix4x4>::New();
       Point3D origin;
       Vector3D right, bottom, normal;
 
       origin = planeGeometry->GetOrigin();
       right  = planeGeometry->GetAxisVector( 0 ); // right = Extent of Image in mm (worldspace)
       bottom = planeGeometry->GetAxisVector( 1 );
       normal = planeGeometry->GetNormal();
 
       right.Normalize();
       bottom.Normalize();
       normal.Normalize();
 
       matrix->SetElement(0, 0, right[0]);
       matrix->SetElement(1, 0, right[1]);
       matrix->SetElement(2, 0, right[2]);
       matrix->SetElement(0, 1, bottom[0]);
       matrix->SetElement(1, 1, bottom[1]);
       matrix->SetElement(2, 1, bottom[2]);
       matrix->SetElement(0, 2, normal[0]);
       matrix->SetElement(1, 2, normal[1]);
       matrix->SetElement(2, 2, normal[2]);
       matrix->SetElement(0, 3, origin[0]);
       matrix->SetElement(1, 3, origin[1]);
       matrix->SetElement(2, 3, origin[2]);
       matrix->SetElement(3, 0, 0.0);
       matrix->SetElement(3, 1, 0.0);
       matrix->SetElement(3, 2, 0.0);
       matrix->SetElement(3, 3, 1.0);
 
       trans->SetMatrix(matrix);
       //Transform the camera to the current position (transveral, coronal and saggital plane).
       this->GetVtkRenderer()->GetActiveCamera()->ApplyTransform(trans);
     }
   }
 }