!7

// Actually the relationship between the white and the black part

// could be much more general. Why do they have to touch each other?

// Why do they need to have the same aspect ratio? Only the area has

// to be the same.

//

// And even that could be lifted by applying a correction factor

// (area white / area black).

//

// Finally, they can even overlap, then you'd use a factor of

// (non-overlapping white area / non-overlapping black area).

//

// No idea if these would then be called "generalized Haar features" or what

//

// The general unit returned by a Haar match should be pixels*brightness

// (value can be negative too).

//

// Result classification:

//   positive = match

//   0        = non-match (indifferent/not applicable)

//   negative = anti-match (Haar feature should be inverted)

p-subst {

  repeat with sleep 1 {

    currentImage(newBufferedImage(200, 200, Color.gray));

    Rect r = randomRect();

    Pair<Rect> p;

    if (tossCoin()) {

      r.h &= ~1; // make even

      p = splitRectInVerticalHalves(r);

    } else {

      r.w &= ~1; // make even

      p = splitRectInHorizontalHalves(r);

    }

    if (oneInTwoChance()) p = reversePair(p);

    fillRect(p.a, Color.black);

    fillRect(p.b, Color.white);

    quickShowImage();

  }

}