# ellipse.rb

    #!/usr/local/bin/ruby18 -w
    require 'RMagick'

    imgl = Magick::ImageList.new
    imgl.new_image(360, 250, Magick::HatchFill.new('white','LightCyan2'))

    gc = Magick::Draw.new

    gc.fill_opacity(0)
    gc.stroke('red').stroke_width(3)

    # Draw ellipse
    gc.ellipse(180,125, 150,75, 0, 270)

    # Draw horizontal width line
    gc.stroke('gray50').stroke_width(1)
    gc.line(180-150, 125, 180, 125)

    # Draw vertical height line
    gc.line(180, 125-75, 180, 125)
    gc.fill_opacity(0)

    # Draw arcStart circle
    gc.circle(180+150, 125, 180+150+3, 125+3)

    # Draw arcEnd circle
    gc.circle(180, 125-75, 180+3, 125-75+3)

    # Annotate
    gc.fill_opacity(1)
    gc.circle(180,125, 183,128)
    gc.fill('black')
    gc.stroke('transparent')
    gc.text(187,125, "'180,125'")
    gc.text(253, 118, "'Start 0 degrees'")
    gc.text(187, 50, "'End 270 degrees'")
    gc.text(120, 100, "'Height=75'")
    gc.text(85, 140, "'Width=150'")
    gc.draw(imgl)

    imgl.border!(1,1, "LightCyan2")

    imgl.write("ellipse.gif")

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