!7

p {
  RGBImage a = loadRGBImage(#1006818), b = loadRGBImage(#1006819);
  compare(a, b);
}

svoid compare(RGBImage a, RGBImage b) {
  //new HashSet<Pt> deltas;
  new Best<Rect> best;
  repeat {
    Rect r = randomScreenRect(50, 50);
    RGBImage clip = a.clip(r);
    if (rgbInnerPrecision(clip) >= 0.5f) {
      Rect r2 = rgbSearchPrecise(b, clip);
      if (r2 != null && neq(r, r2)) {
        Pt delta = new Pt(r2.x-r.x, r2.y-r.y);
        Rect match = expandMatch(a, b, r, r2);
        if (best.put(match, match.w*match.h)) {
          print("New best. Movement: " + delta + ". Match size: " + match.w + "/" + match.h);
          packFrameInTopRightCorner(quickShowImage(rgbScale(a.clip(match), 1)));
        }
      }
    }
  }
}

static Rect expandMatch(RGBImage a, RGBImage b, Rect r1, Rect r2) {
  assertEquals(r1.w, r2.w);
  assertEquals(r1.h, r2.h);
  int w = a.w(), h = a.h();
  print("Comparing " + r1 + " and " + r2);
  repeat {
    Rect r = r1;
    
    // left
    if (r2.x > 0 && r1.x > 0 && rgbImageSectionsIdentical(a, new Rect(r1.x-1, r1.y, 1, r1.h), b, new Rect(r2.x-1, r2.y, 1, r2.h))) {
      r1 = growRectLeft(r1, 1); r2 = growRectLeft(r2, 1);
    }
    
    // right
    if (r2.x2() < w && r2.x2() < w && rgbImageSectionsIdentical(a, new Rect(r1.x2(), r1.y, 1, r1.h), b, new Rect(r2.x2(), r2.y, 1, r2.h))) {
      r1 = growRectRight(r1, 1); r2 = growRectRight(r2, 1);
    }
  
    // top
    if (r2.y > 0 && r1.y > 0 && rgbImageSectionsIdentical(a, new Rect(r1.x, r1.y-1, r1.w, 1), b, new Rect(r2.x, r2.y-1, r2.w, 1))) {
      r1 = growRectTop(r1, 1); r2 = growRectTop(r2, 1);
    }
    
    // bottom
    if (r2.y2() < h && r2.y2() < h && rgbImageSectionsIdentical(a, new Rect(r1.x, r1.y2(), r1.w, 1), b, new Rect(r2.x, r2.y2(), r2.w, 1))) {
      r1 = growRectBottom(r1, 1); r2 = growRectBottom(r2, 1);
    }
    
    if (eq(r, r1)) break;
 
  ret r1;
}