!752

p {
  BWImage img = shootScreenBW();
  print(go(img));
  setFrameTitle("g = " + g, showImageWithSelections(img.getBufferedImage(), clips));
  g = 3;
  print(go(img));
  setFrameTitle("g = " + g, showImageWithSelections(img.getBufferedImage(), clips));
}

static L<Rect> clips;
static int[] grid;
static int gw, gh;
static int g = 4;

static Rect fill(int x, int y, Rect r) {
  if (x < 0 || y < 0 || x >= gw || y >= gh)
    return r;
  int idx = y*gw+x;
  if (grid[idx] == 0)
    return r;
  grid[idx] = 0;
  Rect me = new Rect(x, y, 1, 1);
  if (r == null)
    r = me;
  else
    r = rectUnion(r, me);

  r = fill(x-1, y, r);
  r = fill(x+1, y, r);
  r = fill(x, y-1, r);
  r = fill(x, y+1, r);
  return r;
}

static S go(BWImage img) {
  int w = img.getWidth(), h = img.getHeight();
  gw = w/g;
  gh = h/g; // width & height of grid

  grid = new int[gw*gh];

  for (int gy = 0; gy <= h- g; gy += g)
    next: for (int gx = 0; gx <= w- g; gx += g) {
      float min = 1, max = 0;
      for (int y = gy; y < gy + g; y++)
        for (int x = gx; x < gx + g; x++) {
          float b = img.getPixel(x, y);
          min = Math.min(min, b);
          max = Math.max(max, b);
          if (min < 0.5 && max > 0.5) {
            grid[(gy / g) * gw + (gx / g)] = 2;
            continue next;
          }
        }
    }

  new L<S> result;
  clips = new L;

  for (int y = 0; y < gh; y++)
    for (int x = 0; x < gw; x++) {
      Rect r = fill(x, y, null);
      if (r != null) {
        r = scaleRect(r, g);
        clips.add(r);
        r = autoCropOfBWImage(img, r);

        BWImage cropped = img.clip(r);
        String hash = md5OfBWImage(cropped);

        result.add(r + " -> " + hash);
      }
    }

  return "Floodfill: " + join("|", result);
}