public PhysicsElement findNext(PhysicsElement element, double x, double y) {
      for (int i = elements.indexOf(element)+1; i< elements.size(); i++) { // find
          if (elements.get(i).contains(x,y))    // next element in that position ahead in array
            return elements.get(i);
      }
      for (PhysicsElement e: elements)   // There was no element in that position ahead in array
          if (e.contains(x,y)) return e; // search for an element in that position from begining.
      return element;
   }