get("#356") -- num2hex

get("#485") -- containsColor

-- Job: Distinguish two classes of images

-- Two images are supplied at once, one of each class.

-- Task is to find out if the two images are swapped or not.

--

-- input variables: img1, img2, solution [to last pair]

-- output: a function returning true or false (swapped or no)

function selectColor(img)

  local x, y = math.random(0, img.width-1), math.random(0, img.height-1)

  color = img.getInt(x, y)

end

return function()

  -- select a new color when last guess was wrong

  if solution ~= guess then color = nil end

  if color == nil then

    if solution == nil then

      lastimg1, lastimg2 = img1, img2

      return false -- just return something

    end

    selectColor(lastimg1)

    class2sampled = solution

    print("color of class "..(class2sampled and "2" or "1")..": ".. num2hex(color))

  end

  lastimg1, lastimg2 = img1, img2

  flag1 = containsColor(img1, color)

  flag2 = containsColor(img2, color)

  if flag1 == flag2 then

    color = nil

    return false

  end

  guess = flag1 == class2sampled

  return guess

end