# File vtk/gtk/GtkVTKRenderWindow.rb, line 228
  def initialize
    super

    @CurrentRenderer = nil
    @CurrentCamera = nil
    @CurrentZoom = 1.0
    @CurrentLight = nil

    @ViewportCenterX = 0
    @ViewportCenterY = 0

    @Picker = Vtk::CellPicker.new
    @PickedAssembly = nil
    @PickedProperty = Vtk::Property.new
    @PickedProperty.SetColor(1, 0, 0)
    @PrePickedProperty = nil

    @OldFocus = nil

    # these record the previous mouse position
    @LastX = 0
    @LastY = 0
  end