    #! /usr/local/bin/ruby -w

    require 'RMagick'

    pr = Magick::Draw.new

    # Outline the image
    pr.stroke('lavender')
    pr.fill_opacity(0)
    pr.stroke_width(1)
    pr.rectangle(0,0,249,199)

    # Define a clip-path.
    pr.define_clip_path('example') {    # The name of the clip-path is "example"
        pr.polygon(125,37.5,    139.5,80.5, 184.5,80.5,  148.5,107.5,
                   161.5,150.5, 125,125,    88.5,150.5,  101.5,107.5,
                   65.5,80.5,   110.5,80.5)
        }                               # End the clip-path definition

    pr.clip_path('example')             # Enable the clip-path

    # Composite the Balloon Girl image over
    # the background using the clip-path
    bg = Magick::ImageList.new "images/Balloon_Girl.jpg"
    pr.composite(0,0, 250,200, bg)

    # Just for illustration, outline the clip-path in blue.
    pr.stroke('blue')
    pr.stroke_width(2)
    pr.fill_opacity(0)
    pr.polygon(125,37.5,    139.5,80.5, 184.5,80.5,  148.5,107.5,
               161.5,150.5, 125,125,    88.5,150.5,  101.5,107.5,
               65.5,80.5,   110.5,80.5)

    # Create a canvas to draw on
    img = Magick::ImageList.new
    img.new_image(250,200) { self.background_color = 'transparent' }

    # Execute the primitives
    pr.draw(img)
    #img.display
    img.write("clip_path.gif")

    exit