void mitk::SurfaceGLMapper2D::Paint(mitk::BaseRenderer * renderer)
{
  bool visible = true;
  GetDataNode()->GetVisibility(visible, renderer, "visible");
  if(!visible) return;

  Surface::Pointer input  = const_cast<Surface*>(this->GetInput());

  if(input.IsNull())
    return;

  //
  // get the TimeGeometry of the input object
  //
  const TimeGeometry* inputTimeGeometry = input->GetTimeGeometry();
  if(( inputTimeGeometry == NULL ) || ( inputTimeGeometry->CountTimeSteps() == 0 ) )
    return;

  m_LineWidth = 1;
  GetDataNode()->GetIntProperty("line width", m_LineWidth, renderer);

  //
  // get the world time
  //
  ScalarType time =renderer->GetTime();
  int timestep=0;

  if( time > itk::NumericTraits<mitk::ScalarType>::NonpositiveMin() )
    timestep = inputTimeGeometry->TimePointToTimeStep( time );

 // int timestep = this->GetTimestep();

  if( inputTimeGeometry->IsValidTimeStep( timestep ) == false )
    return;

  vtkPolyData * vtkpolydata = input->GetVtkPolyData( timestep );
  if((vtkpolydata==NULL) || (vtkpolydata->GetNumberOfPoints() < 1 ))
    return;

  //apply color and opacity read from the PropertyList
  this->ApplyAllProperties(renderer);

  if (m_DrawNormals)
  {
    m_PointLocator->SetDataSet( vtkpolydata );
    m_PointLocator->BuildLocatorFromPoints( vtkpolydata->GetPoints() );
  }

  if(vtkpolydata!=NULL)
  {
    Point3D point;
    Vector3D normal;

    //Check if Lookup-Table is already given, else use standard one.
    double* scalarLimits = m_LUT->GetTableRange();
    double scalarsMin = scalarLimits[0], scalarsMax = scalarLimits[1];

    vtkLookupTable *lut;

    LookupTableProperty::Pointer lookupTableProp;
    this->GetDataNode()->GetProperty(lookupTableProp, "LookupTable", renderer);
    if (lookupTableProp.IsNotNull() )
    {
      lut = lookupTableProp->GetLookupTable()->GetVtkLookupTable();

      GetDataNode()->GetDoubleProperty("ScalarsRangeMinimum", scalarsMin, renderer);
      GetDataNode()->GetDoubleProperty("ScalarsRangeMaximum", scalarsMax, renderer);

      // check if the scalar range has been changed, e.g. manually, for the data tree node, and rebuild the LUT if necessary.
      double* oldRange = lut->GetTableRange();
      if( oldRange[0] != scalarsMin || oldRange[1] != scalarsMax )
      {
        lut->SetTableRange(scalarsMin, scalarsMax);
        lut->Build();
      }
    }
    else
    {
      lut = m_LUT;
    }

    vtkLinearTransform * vtktransform = GetDataNode()->GetVtkTransform(timestep);
    PlaneGeometry::ConstPointer worldGeometry = renderer->GetCurrentWorldPlaneGeometry();
    assert( worldGeometry.IsNotNull() );
    if (worldGeometry.IsNotNull())
    {
      // set up vtkPlane according to worldGeometry
      point=worldGeometry->GetOrigin();
      normal=worldGeometry->GetNormal(); normal.Normalize();
      m_Plane->SetTransform((vtkAbstractTransform*)NULL);
    }
    else
    {
      AbstractTransformGeometry::ConstPointer worldAbstractGeometry = dynamic_cast<const AbstractTransformGeometry*>(renderer->GetCurrentWorldPlaneGeometry());
      if(worldAbstractGeometry.IsNotNull())
      {
        AbstractTransformGeometry::ConstPointer surfaceAbstractGeometry = dynamic_cast<const AbstractTransformGeometry*>(input->GetTimeGeometry()->GetGeometryForTimeStep(0).GetPointer());
        if(surfaceAbstractGeometry.IsNotNull()) //@todo substitude by operator== after implementation, see bug id 28
        {
          PaintCells(renderer, vtkpolydata, worldGeometry, renderer->GetDisplayGeometry(), vtktransform, lut);
          return;
        }
        else
        {
          //@FIXME: does not work correctly. Does m_Plane->SetTransform really transforms a "flat plane" into a "curved plane"?
          return;
          // set up vtkPlane according to worldGeometry
          point=const_cast<BoundingBox*>(worldAbstractGeometry->GetParametricBoundingBox())->GetMinimum();
          FillVector3D(normal, 0, 0, 1);
          m_Plane->SetTransform(worldAbstractGeometry->GetVtkAbstractTransform()->GetInverse());
        }
      }
      else
        return;
    }

    double vp[3], vnormal[3];

    vnl2vtk(point.GetVnlVector(), vp);
    vnl2vtk(normal.GetVnlVector(), vnormal);

    //normally, we would need to transform the surface and cut the transformed surface with the cutter.
    //This might be quite slow. Thus, the idea is, to perform an inverse transform of the plane instead.
    //@todo It probably does not work for scaling operations yet:scaling operations have to be
    //dealed with after the cut is performed by scaling the contour.
    vtkLinearTransform * inversetransform = vtktransform->GetLinearInverse();
    inversetransform->TransformPoint(vp, vp);
    inversetransform->TransformNormalAtPoint(vp, vnormal, vnormal);

    m_Plane->SetOrigin(vp);
    m_Plane->SetNormal(vnormal);

    //set data into cutter
    m_Cutter->SetInputData(vtkpolydata);
    m_Cutter->Update();
    //    m_Cutter->GenerateCutScalarsOff();
    //    m_Cutter->SetSortByToSortByCell();

    if (m_DrawNormals)
    {
      m_Stripper->SetInputData( m_Cutter->GetOutput() );
      // calculate the cut
      m_Stripper->Update();
      PaintCells(renderer, m_Stripper->GetOutput(), worldGeometry, renderer->GetDisplayGeometry(), vtktransform, lut, vtkpolydata);
    }
    else
    {
      PaintCells(renderer, m_Cutter->GetOutput(), worldGeometry, renderer->GetDisplayGeometry(), vtktransform, lut, vtkpolydata);
    }
  }
}
void mitk::UnstructuredGridMapper2D::Paint( mitk::BaseRenderer* renderer )
{
  if ( IsVisible( renderer ) == false )
    return ;

  vtkLinearTransform * vtktransform = GetDataNode()->GetVtkTransform();
  vtkLinearTransform * inversetransform = vtktransform->GetLinearInverse();

  Geometry2D::ConstPointer worldGeometry = renderer->GetCurrentWorldGeometry2D();
  PlaneGeometry::ConstPointer worldPlaneGeometry = dynamic_cast<const PlaneGeometry*>( worldGeometry.GetPointer() );

  Point3D point;
  Vector3D normal;

  if(worldPlaneGeometry.IsNotNull())
  {
    // set up vtkPlane according to worldGeometry
    point=worldPlaneGeometry->GetOrigin();
    normal=worldPlaneGeometry->GetNormal(); normal.Normalize();
    m_Plane->SetTransform((vtkAbstractTransform*)NULL);
  }
  else
  {
    //@FIXME: does not work correctly. Does m_Plane->SetTransform really transforms a "plane plane" into a "curved plane"?
    return;
    AbstractTransformGeometry::ConstPointer worldAbstractGeometry = dynamic_cast<const AbstractTransformGeometry*>(renderer->GetCurrentWorldGeometry2D());
    if(worldAbstractGeometry.IsNotNull())
    {
      // set up vtkPlane according to worldGeometry
      point=const_cast<mitk::BoundingBox*>(worldAbstractGeometry->GetParametricBoundingBox())->GetMinimum();
      FillVector3D(normal, 0, 0, 1);
      m_Plane->SetTransform(worldAbstractGeometry->GetVtkAbstractTransform()->GetInverse());
    }
    else
      return;
  }

  vtkFloatingPointType vp[ 3 ], vnormal[ 3 ];

  vnl2vtk(point.Get_vnl_vector(), vp);
  vnl2vtk(normal.Get_vnl_vector(), vnormal);

  //normally, we would need to transform the surface and cut the transformed surface with the cutter.
  //This might be quite slow. Thus, the idea is, to perform an inverse transform of the plane instead.
  //@todo It probably does not work for scaling operations yet:scaling operations have to be
  //dealed with after the cut is performed by scaling the contour.
  inversetransform->TransformPoint( vp, vp );
  inversetransform->TransformNormalAtPoint( vp, vnormal, vnormal );

  m_Plane->SetOrigin( vp );
  m_Plane->SetNormal( vnormal );

  // set data into cutter
  m_Slicer->SetInput( m_VtkPointSet );
  //    m_Cutter->GenerateCutScalarsOff();
  //    m_Cutter->SetSortByToSortByCell();

  // calculate the cut
  m_Slicer->Update();

  // fetch geometry
  mitk::DisplayGeometry::Pointer displayGeometry = renderer->GetDisplayGeometry();
  assert( displayGeometry );
  //  float toGL=displayGeometry->GetSizeInDisplayUnits()[1];

  //apply color and opacity read from the PropertyList
  ApplyProperties( renderer );

  // traverse the cut contour
  vtkPolyData * contour = m_Slicer->GetOutput();

  vtkPoints *vpoints = contour->GetPoints();
  vtkCellArray *vlines = contour->GetLines();
  vtkCellArray *vpolys = contour->GetPolys();
  vtkPointData *vpointdata = contour->GetPointData();
  vtkDataArray* vscalars = vpointdata->GetScalars();

  vtkCellData *vcelldata = contour->GetCellData();
  vtkDataArray* vcellscalars = vcelldata->GetScalars();

  const int numberOfLines = contour->GetNumberOfLines();
  const int numberOfPolys = contour->GetNumberOfPolys();

  const bool useCellData = m_ScalarMode->GetVtkScalarMode() == VTK_SCALAR_MODE_DEFAULT ||
              m_ScalarMode->GetVtkScalarMode() == VTK_SCALAR_MODE_USE_CELL_DATA;
  const bool usePointData = m_ScalarMode->GetVtkScalarMode() == VTK_SCALAR_MODE_USE_POINT_DATA;

  Point3D p;
  Point2D p2d;

  vlines->InitTraversal();
  vpolys->InitTraversal();
  
  mitk::Color outlineColor = m_Color->GetColor();

  glLineWidth((float)m_LineWidth->GetValue());

  for (int i = 0;i < numberOfLines;++i )
  {
    vtkIdType *cell(0);
    vtkIdType cellSize(0);

    vlines->GetNextCell( cellSize, cell );

    float rgba[4] = {outlineColor[0], outlineColor[1], outlineColor[2], 1.0f};
    if (m_ScalarVisibility->GetValue() && vcellscalars)
    {
      if ( useCellData )
      {  // color each cell according to cell data
        double scalar = vcellscalars->GetComponent( i, 0 );
        double rgb[3] = { 1.0f, 1.0f, 1.0f };
        m_ScalarsToColors->GetColor(scalar, rgb);
        rgba[0] = (float)rgb[0];
        rgba[1] = (float)rgb[1];
        rgba[2] = (float)rgb[2];
        rgba[3] = (float)m_ScalarsToOpacity->GetValue(scalar);
      }
      else if ( usePointData )
      {
        double scalar = vscalars->GetComponent( i, 0 );
        double rgb[3] = { 1.0f, 1.0f, 1.0f };
        m_ScalarsToColors->GetColor(scalar, rgb);
        rgba[0] = (float)rgb[0];
        rgba[1] = (float)rgb[1];
        rgba[2] = (float)rgb[2];
        rgba[3] = (float)m_ScalarsToOpacity->GetValue(scalar);
      }
    }
    
    glColor4fv( rgba );
    
    glBegin ( GL_LINE_LOOP );
    for ( int j = 0;j < cellSize;++j )
    {
      vpoints->GetPoint( cell[ j ], vp );
      //take transformation via vtktransform into account
      vtktransform->TransformPoint( vp, vp );

      vtk2itk( vp, p );

      //convert 3D point (in mm) to 2D point on slice (also in mm)
      worldGeometry->Map( p, p2d );

      //convert point (until now mm and in worldcoordinates) to display coordinates (units )
      displayGeometry->WorldToDisplay( p2d, p2d );

      //convert display coordinates ( (0,0) is top-left ) in GL coordinates ( (0,0) is bottom-left )
      //p2d[1]=toGL-p2d[1];

      //add the current vertex to the line
      glVertex2f( p2d[0], p2d[1] );
    }
    glEnd ();

  }
  
  bool polyOutline = m_Outline->GetValue();
  bool scalarVisibility = m_ScalarVisibility->GetValue();

  // only draw polygons if there are cell scalars
  // or the outline property is set to true
  if ((scalarVisibility && vcellscalars) || polyOutline)
  {
    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);

    // cache the transformed points
    // a fixed size array is way faster than 'new'
    // slices through 3d cells usually do not generated
    // polygons with more than 6 vertices
    Point2D cachedPoints[10];

    for (int i = 0;i < numberOfPolys;++i )
    {
      vtkIdType *cell(0);
      vtkIdType cellSize(0);

      vpolys->GetNextCell( cellSize, cell );

      float rgba[4] = {1.0f, 1.0f, 1.0f, 0};
      if (scalarVisibility && vcellscalars)
      {
        if ( useCellData )
        {  // color each cell according to cell data
          double scalar = vcellscalars->GetComponent( i, 0 );
          double rgb[3] = { 1.0f, 1.0f, 1.0f };
          m_ScalarsToColors->GetColor(scalar, rgb);
          rgba[0] = (float)rgb[0];
          rgba[1] = (float)rgb[1];
          rgba[2] = (float)rgb[2];
          rgba[3] = (float)m_ScalarsToOpacity->GetValue(scalar);
        }
        else if ( usePointData )
        {
          double scalar = vscalars->GetComponent( i, 0 );
          double rgb[3] = { 1.0f, 1.0f, 1.0f };
          m_ScalarsToColors->GetColor(scalar, rgb);
          rgba[0] = (float)rgb[0];
          rgba[1] = (float)rgb[1];
          rgba[2] = (float)rgb[2];
          rgba[3] = (float)m_ScalarsToOpacity->GetValue(scalar);
        }
      }
      glColor4fv( rgba );

      glBegin( GL_POLYGON );
      for (int j = 0; j < cellSize; ++j)
      {
        vpoints->GetPoint( cell[ j ], vp );
        //take transformation via vtktransform into account
        vtktransform->TransformPoint( vp, vp );

        vtk2itk( vp, p );

        //convert 3D point (in mm) to 2D point on slice (also in mm)
        worldGeometry->Map( p, p2d );

        //convert point (until now mm and in worldcoordinates) to display coordinates (units )
        displayGeometry->WorldToDisplay( p2d, p2d );

        //convert display coordinates ( (0,0) is top-left ) in GL coordinates ( (0,0) is bottom-left )
        //p2d[1]=toGL-p2d[1];

        cachedPoints[j][0] = p2d[0];
        cachedPoints[j][1] = p2d[1];

        //add the current vertex to the line
        glVertex2f( p2d[0], p2d[1] );
      }
      glEnd();

      if (polyOutline)
      {
        glColor4f(outlineColor[0], outlineColor[1], outlineColor[2], 1.0f);

        glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
        glBegin( GL_POLYGON );
        //glPolygonOffset(1.0, 1.0);
        for (int j = 0; j < cellSize; ++j)
        {
          //add the current vertex to the line
          glVertex2f( cachedPoints[j][0], cachedPoints[j][1] );
        }
        glEnd();
      }
    }
    glDisable(GL_BLEND);
  }
}
void mitk::PolyDataGLMapper2D::Paint( mitk::BaseRenderer * renderer )
{
    if ( IsVisible( renderer ) == false )
        return ;

    // ok, das ist aus GenerateData kopiert
    mitk::BaseData::Pointer input = const_cast<mitk::BaseData*>( GetData() );

    assert( input );

    input->Update();

    vtkPolyData * vtkpolydata = this->GetVtkPolyData();
    assert( vtkpolydata );


    vtkLinearTransform * vtktransform = GetDataNode() ->GetVtkTransform();

    if (vtktransform)
    {
      vtkLinearTransform * inversetransform = vtktransform->GetLinearInverse();

      Geometry2D::ConstPointer worldGeometry = renderer->GetCurrentWorldGeometry2D();
      PlaneGeometry::ConstPointer worldPlaneGeometry = dynamic_cast<const PlaneGeometry*>( worldGeometry.GetPointer() );

      if ( vtkpolydata != NULL )
      {
          Point3D point;
          Vector3D normal;

          if(worldPlaneGeometry.IsNotNull())
          {
            // set up vtkPlane according to worldGeometry
            point=worldPlaneGeometry->GetOrigin();
            normal=worldPlaneGeometry->GetNormal(); normal.Normalize();
            m_Plane->SetTransform((vtkAbstractTransform*)NULL);
          }
          else
          {
            //@FIXME: does not work correctly. Does m_Plane->SetTransform really transforms a "plane plane" into a "curved plane"?
            return;
            AbstractTransformGeometry::ConstPointer worldAbstractGeometry = dynamic_cast<const AbstractTransformGeometry*>(renderer->GetCurrentWorldGeometry2D());
            if(worldAbstractGeometry.IsNotNull())
            {
              // set up vtkPlane according to worldGeometry
              point=const_cast<mitk::BoundingBox*>(worldAbstractGeometry->GetParametricBoundingBox())->GetMinimum();
              FillVector3D(normal, 0, 0, 1);
              m_Plane->SetTransform(worldAbstractGeometry->GetVtkAbstractTransform()->GetInverse());
            }
            else
              return;
          }

          vtkFloatingPointType vp[ 3 ], vnormal[ 3 ];

          vnl2vtk(point.Get_vnl_vector(), vp);
          vnl2vtk(normal.Get_vnl_vector(), vnormal);

          //normally, we would need to transform the surface and cut the transformed surface with the cutter.
          //This might be quite slow. Thus, the idea is, to perform an inverse transform of the plane instead.
          //@todo It probably does not work for scaling operations yet:scaling operations have to be
          //dealed with after the cut is performed by scaling the contour.
          inversetransform->TransformPoint( vp, vp );
          inversetransform->TransformNormalAtPoint( vp, vnormal, vnormal );

          m_Plane->SetOrigin( vp );
          m_Plane->SetNormal( vnormal );

          // set data into cutter
          m_Cutter->SetInput( vtkpolydata );
          //    m_Cutter->GenerateCutScalarsOff();
          //    m_Cutter->SetSortByToSortByCell();

          // calculate the cut
          m_Cutter->Update();

          // fetch geometry
          mitk::DisplayGeometry::Pointer displayGeometry = renderer->GetDisplayGeometry();
          assert( displayGeometry );
          //  float toGL=displayGeometry->GetSizeInDisplayUnits()[1];

          //apply color and opacity read from the PropertyList
          ApplyProperties( renderer );

          // traverse the cut contour
          vtkPolyData * contour = m_Cutter->GetOutput();

          vtkPoints *vpoints = contour->GetPoints();
          vtkCellArray *vpolys = contour->GetLines();
          vtkPointData *vpointdata = contour->GetPointData();
          vtkDataArray* vscalars = vpointdata->GetScalars();

          vtkCellData *vcelldata = contour->GetCellData();
          vtkDataArray* vcellscalars = vcelldata->GetScalars();

          int i, numberOfCells = vpolys->GetNumberOfCells();

          Point3D p;
          Point2D p2d, last, first;

          vpolys->InitTraversal();
          vtkScalarsToColors* lut = GetVtkLUT();
          assert ( lut != NULL );

          for ( i = 0;i < numberOfCells;++i )
          {
              vtkIdType *cell(NULL);
              vtkIdType cellSize(0);

              vpolys->GetNextCell( cellSize, cell );

              if ( m_ColorByCellData )
              {  // color each cell according to cell data
                vtkFloatingPointType* color = lut->GetColor( vcellscalars->GetComponent( i, 0 ) );
                glColor3f( color[ 0 ], color[ 1 ], color[ 2 ] );
              }
              if ( m_ColorByPointData )
              {
                vtkFloatingPointType* color = lut->GetColor( vscalars->GetComponent( cell[0], 0 ) );
                glColor3f( color[ 0 ], color[ 1 ], color[ 2 ] );
              }

              glBegin ( GL_LINE_LOOP );
              for ( int j = 0;j < cellSize;++j )
              {
                  vpoints->GetPoint( cell[ j ], vp );
                  //take transformation via vtktransform into account
                  vtktransform->TransformPoint( vp, vp );

                  vtk2itk( vp, p );

                  //convert 3D point (in mm) to 2D point on slice (also in mm)
                  worldGeometry->Map( p, p2d );

                  //convert point (until now mm and in worldcoordinates) to display coordinates (units )
                  displayGeometry->WorldToDisplay( p2d, p2d );

                  //convert display coordinates ( (0,0) is top-left ) in GL coordinates ( (0,0) is bottom-left )
                  //p2d[1]=toGL-p2d[1];

                  //add the current vertex to the line
                  glVertex2f( p2d[0], p2d[1] );
              }
              glEnd ();
          }
      }
    }
}