Whyday 2011

Happy Whyday! We’re doing a last minute contest that will end next Monday. This weekend, put your best practices away and celebrate Why’s contributions to our unique culture. Create something wonderful. If you’re still looking for something to build, check out some of the example ideas on the Whyday website.

Go wild! Put your work in a Gist and include a README explaining what it does and how it works. Again, you only have until Monday, so get started as soon as you can!

Happy hacking!

Prize

This week’s winner will receive a code for $25 worth of credit for the 6sync hosting platform!

This contest is finished

Congratulations to this week's winners! The entries and the contestant names are shown below.

Joris van Rooij

foxes

#!/usr/bin/env ruby

require File.join(File.dirname(__FILE__), 'foxes.rb')

unless ARGV.length == 1
  $stderr.puts "Usage: #{$0} input.png"
  exit 1
end

begin
  input = File.open(ARGV[0], 'r')

  foxes = Foxes.new input
rescue
  $stderr.puts "Argh! #{$!}"
  exit 1
end

begin
  foxes.execute
rescue Foxes::NotFoxified
  $stderr.puts "#{ARGV[0]} is not yet foxified!"
  exit 1
end

foxify

#!/usr/bin/env ruby

require File.join(File.dirname(__FILE__), 'foxes.rb')

unless ARGV.length == 3
  $stderr.puts "Usage: #{$0} input.png code.rb output.png"
  exit 1
end

begin
  modes = %w{r r w+}
  input, code, output = *ARGV.map { |a| File.open(a, modes.shift) }

  foxes = Foxes.new input
  foxes.foxify code
  foxes.png output
rescue
  $stderr.puts "Argh! #{$!}"
  exit 1
end

README.md

Foxes

Adds Ruby code to a PNG file. This allows foxes to run a PNG file as Ruby code, while keeping the PNG file intact and viewable. It basically just adds the "ruby" ancillary FourCC to the PNG spec and throws the code in.

If you read the PNG spec, you'll notice PNG is just like bacon.

The foxes are licensed by why the lucky stiff under the CC BY-SA 2.0 license, and are part of why's (poignant) guide to Ruby.

Usage

$ ./foxify foxes.png bacon.rb output.png
$ ./foxes output.png
Chunky bacon!!
Chunky bacon!!

foxes.png

bacon.rb

2.times do
  puts "Chunky bacon!!"
end

foxes.rb

require 'zlib'

class Foxes
  PNG_HEADER = "\x89PNG\r\n\x1A\n"
  class NotFoxified < RuntimeError; end
  
  # Foxes accepts a File pointing to a PNG image.
  def initialize(file)
    @file = file
    @file.seek 0

    if @file.read(8) != PNG_HEADER
      raise ArgumentError, 'Not a PNG file!'
    end

    # Simple way to read the PNG file.
    @chunks = {}
    while !@file.eof?
      length, type = *@file.read(8).unpack('NA*')
      data = @file.read length
      crc = @file.read(4).unpack('N').first

      if Zlib::crc32(type + data) != crc
        raise RuntimeError, "CRC checksum error on #{type}"
      end
      
      @chunks[type] ||= []
      @chunks[type] << data
    end
  end

  # Adds to code in the file to the PNG file.
  def foxify(file)
    @chunks['ruby'] = [Zlib::Deflate.deflate(file.read)]
  end

  # Executes the Ruby code in the PNG file.
  def execute
    raise NotFoxified unless @chunks['ruby']
    Object.class_eval(Zlib::Inflate.inflate(@chunks['ruby'].join),
                      @file.path)
  end

  # Writes the PNG data to file.
  def png(file)
    file.write PNG_HEADER

    # Make sure IEND is actually at the end (Ruby 1.9).
    iend = @chunks.delete 'IEND'
    @chunks['IEND'] = iend

    @chunks.each do |type, data|
      data.each do |data_part|
        file.write [data_part.length, type].pack('NA*')
        file.write data_part
        file.write [Zlib::crc32(type + data_part)].pack('N')
      end
    end
  end
end

View full entry

Finished in 1st place with a final score of 4.0/5. (View the Gist)

Benoit Daloze

README.md

Binary Clock

A simple and concise (474 bytes minified, 1KB normal) binary clock in Shoes.

Compatible with Shoes 2 (Raisins) and 3 (Policeman).

Design inspired by The Game of Life on the ShoeBox.

capture.png

binary_clock.rb

margin, space, width = 30, 20, 24
with_help = true

Shoes.app :title => "Binary Clock",
          :width =>  6*width+5*space+2*margin,
          :height => 3*width+2*space+2*margin,
          :resizable => false do

  on, off = rgb(0, 0, 255, 0.45), gray(0,0)

  if Shoes::VERSION == 'Policeman'
    background rgb(6, 6, 89)
  else
    background gradient(rgb(0, 0, 128), rgb(12, 12, 50))
  end
  stroke gray(1.0, 0.5)
  strokewidth 2.5
  fill off

  lights = Array.new(3) { |i|
    Array.new(6) { |j|
      next if i == 0 and j == 5 # The first light is not needed for hours
      x, y = margin + (5-j)*(space+width), margin + i*(space+width)
      para 2**j, :size => 'xx-small', :left => x+20, :top => y+20, :stroke => gray if with_help
      oval x, y, width
    }
  } and lights.first.compact!

  every 1 do
    now = Time.now
    [now.hour, now.min, now.sec].zip(lights) { |v, row|
      row.each_with_index { |light, i|
        light.style :fill => (v[i] == 1 ? on : off)
      }
    }
  end
end

binary_clock.minified.rb

Shoes.app(:title=>"Binary Clock",:width=>304,:height=>172,:resizable=>false){
on,off=rgb(0,0,255,0.45),gray(0,0);background rgb(6,6,89)
stroke gray(1.0,0.5);strokewidth 2.5;fill off
lights=Array.new(3){|i|Array.new(6){|j|next if j-i==5;x,y=250-j*44,30+i*44
para 2**j,:size=>'xx-small',:left=>x+20,:top=>y+20,:stroke=>gray;oval x,y,24}}
lights[0].pop;every(1){now=Time.now;[now.hour,now.min,now.sec].zip(lights){|v,r|
r.each_with_index{|l,j|l.style:fill=>(v[j]==1?on:off)}}}}