int setHeight = 60;
color setColour = color(184 + random(-40, 40),
                        124 + random(-40, 40),
                        124 + random(-40, 40));
int wid = 600;

void setup() {
  size(wid, (int)((log(wid) / log(3) + 1) * (setHeight + 5)));
  background(0);
  smooth();
  
  cantorSet(10, 10, width - 20, setColour);
  
  save("cantorSet.png");
}

float rnd(float x) {
  return x + random(-20, 20);
}

void brushRect(int x, int y, int w, int h) {
  for (int i = 0; i < h; ++i) {
    float r = random(3);
    strokeWeight(r);
    float downpull = random(h / 4);
    float shudder = random(-2, 2);
    line(x + shudder, y + i, x + w - shudder, y + i + downpull);
  }
}

void cantorSet(int y, int offX, int wid, color col) {
  if ((y > height - 10) || (wid < 1))
    return;

  stroke(col);
  brushRect(offX, y, wid, setHeight);
  //fill(col);
  //rect(offX, y, wid, setHeight);
  
  color newCol = color(rnd(red(col)), rnd(green(col)),
                      rnd(blue(col)));
  cantorSet(y + setHeight + 5, offX, wid / 3, newCol);
  cantorSet(y + setHeight + 5, offX + wid*2/3, wid / 3, newCol);
}

# The Array power set is stolen from http://snippets.dzone.com/posts/show/3524
class Array
  # Returns the "power set" for this Array. This means that an array with all
  # subsets of the array's elements will be returned.
  def power_set
    # the power set line is stolen from http://johncarrino.net/blog/2006/08/11/powerset-in-ruby/
    inject([[]]){|c,y|r=[];c.each{|i|r<<i;r<<i+[y]};r}
  end
end

class Hash
  def power_set
    # Returns the "power set" for this Hash. This means that a array with hashes of all
    # subsets of the hash's (key => value) pairs will be returned.
    # Example:
    # >> {:feedback_type=>"", :language_code=>"", :comment=>""}.power_set
    #
    # [{}, {:comment=>""}, {:language_code=>""}, {:language_code=>"", :comment=>""}, {:feedback_type=>""}, {:feedback_type=>"", :comment=>""}, {:feedback_type=>"", :language_code=>""}, {:feedback_type=>"", :language_code=>"", :comment=>""}]
    
    hash_to_array = self.to_a
    array_power_set = hash_to_array.power_set
    hash_power_set = array_power_set.collect { |pairs| pairs.inject({}) { |hash,pair| hash[pair[0]] = pair[1]; hash } }
    hash_power_set
  end
end