add methods to rmagick to generate Conway's life iterations

lifemagick.rb

require 'rubygems'
require 'RMagick'

# add methods to rmagick to generate Conway's life iterations

module Magick

  class Image

    def occupied?(x, y); pixel_color(x, y).to_color == 'black' end

    def neighbors(x, y)
      [
        [x - 1, y - 1],
        [x, y - 1],
        [x + 1, y - 1],
        [x + 1, y],
        [x + 1, y + 1],
        [x, y + 1],
        [x - 1, y + 1],
        [x - 1, y]].collect { |x,y| occupied?(x, y) ? 1 : 0 }.
      inject { |sum,n| sum + n }
    end

    def life_next
      next_iter = copy

      (0...rows).each do |x|
        (0...columns).each do |y|
          nb = neighbors(x, y)
          next_iter.pixel_color(x, y,
            (nb == 3 or (occupied?(x, y) and nb == 2)) ? 'black' : 'white')
        end
      end

      next_iter
    end

  end

  class Magick::ImageList

    def add_life_next(n=1)
      n.times { self << last.life_next }
    end

  end
end

blob = <<-eos
/* XPM */
static char * xpm[] = {
"32 32 2 1",
" 	c #ffffff",
".	c #000000",
"                                ",
"               ......           ",
"            ..........          ",
"            ...........         ",
"          ..............        ",
"          ..............        ",
"         ................       ",
"        ....      ..   ..       ",
"        ..             ...      ",
"        ..             ...      ",
"        ..              ..      ",
"        .               ..      ",
"       ..    ..     .   ..      ",
"        .  . ..   ..... ..      ",
"        .   . .   ....  ..      ",
"        .         ..     .      ",
"                                ",
"                  .             ",
"                                ",
"         .       ..     .       ",
"         .      ....    .       ",
"         ..   .......   .       ",
"         ..  ............       ",
"          ....     ... .        ",
"          .... .........        ",
"          ..... ... ....        ",
"           ............         ",
"            ............        ",
"             ........           ",
"               ....             ",
"                 .              ",
"                                "};
eos

img = Magick::ImageList.new
img.from_blob(blob)
img.add_life_next(82)

img.delay = 75

# img.to_a.each do |i|
#   i.resize!(512, 512, filter=Magick::LanczosFilter, support=0.0)
# end

img.write('anim.gif')