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

    require 'RMagick'

    gc = Magick::Draw.new
    gc.pattern('checkerboard', 0, 0, 16, 16) {
        gc.fill('red')
        gc.stroke('black')
        gc.rectangle(0,0,7,7)
        gc.rectangle(8,8,15,15)
        gc.fill('black')
        gc.rectangle(8,0,15,7)
        gc.rectangle(0,8,7,15)
    }

    gc.stroke('checkerboard')
    gc.stroke_width(16)
    gc.fill_opacity(0)
    gc.ellipse(150, 75, 130, 60, 0, 360)

    i = Magick::ImageList.new
    i.new_image(300, 150, Magick::HatchFill.new('white','gray90',8))
    gc.draw(i)

    #i.display
    i.write('pattern1.gif')
    exit