# File vtk/tk/vtkTkImageViewerWidget.rb, line 246
  def ResetTkImageViewer
    # Reset: Set window level to show all values
    viewer = @ImageViewer
    input = viewer.GetInput
    if input == nil
      return nil
    end

    # Get the extent in viewer
    z = viewer.GetZSlice

    input.SetUpdateExtent(-99999,99999,-99999,99999,z,z)
    input.Update

    low,high = input.GetScalarRange
   
    viewer.SetColorWindow(high - low)
    viewer.SetColorLevel((high + low) * 0.5)

    self.Render
  end