-- iterated sierpsinsky renderer

iterations = 100000

local x,y

x = width/2
y = height/2

for iter=0, iterations do
    choice=math.random()

   if choice > 0.66 then
      x = (x+0.5 * width) / 2
      y = (y+0.0 * height) / 2
   elseif choice > 0.33 then
      x = (x+1   * width) / 2
      y = (y+1.0 * height) / 2
   else
      x = (x+0   * width) / 2
      y = (y+1.0 * height) / 2
   end
    
   set_value (x,y, 1)
   progress (iter / iterations)
end