// similarity = e.g. 0.99f

static L<FoundImg> bwRawImageSearchInPart(BWImage big, BWImage pat, Rect part, float similarity, int maxEntries) {

  new L<FoundImg> found;

  int wp = pat.getWidth(), hp = pat.getHeight();

  int w = big.getWidth(), h = big.getHeight();

  float maxError = (1f-similarity)*wp*hp;

  int x2 = min(w-wp, part.x2());

  int y2 = min(h-hp, part.y2());

  for (int y = part.y; y < y2; y++)

    for (int x = part.x; x < x2; x++) {

      float diff = bwImageSectionsSimilarity(big, pat, x, y, maxError);

      if (diff <= maxError) {

        float sim = 1-diff/(wp*hp);

        Rect r = new Rect(x, y, wp, hp);

        found.add(new FoundImg(r, sim));

        ping();

        if (l(found) >= maxEntries) ret found;

        x += wp-1;

      }

    }

  ret found;

}