# File easy_vtk.rb, line 901
  def fixed_text( str, x, y, options={} )
    vertical_justification = false
    horizontal_justification = false
    color = false
    options.each{ |key, val|
      case key
      when 'vertical_justification'
        vertical_justification = val
      when 'horizontal_justification'
        horizontal_justification = val
      when 'color'
        unless Array === val
          raise "value of option['color'] must be Array"
        end
        color = val
      else
        raise "option (#{key}) is invalid"
      end
    }
    text = Vtk::TextMapper.new
    text.SetInput( str )
    prop = text.GetTextProperty
    if vertical_justification
      case vertical_justification
      when 'bottom'
        prop.SetVerticalJustificationToBottom
      when 'top'
        prop.SetVerticalJustificationToTop
      when 'center'
        prop.SetVerticalJustificationToCentered
      else
        raise "value of option['vertical_justification'] (=#{val}) is invalid"
      end
    end
    if horizontal_justification
      case horizontal_justification
      when 'left'
        prop.SetJustificationToLeft
      when 'right'
        prop.SetJustificationToRight
      when 'center'
        prop.SetJustificationToCentered
      else
        raise "value of option['horizontal_justification'] (=#{val}) is invalid"
      end
    end
    prop.SetColor( color ) if color
    actor = Vtk::Actor2D.new
    actor.SetMapper( text )
    actor.GetPositionCoordinate.SetCoordinateSystemToNormalizedDisplay
    actor.GetPositionCoordinate.SetValue( x, y )
    @ren.AddActor( actor )
    return nil
  end