private void updateAnimators(float delta) {
   if (animators.size() > 0) {
     for (Animator animator : animators) {
       animator.update(delta);
       if (animator.didFinish()) {
         animatorsToRemove.add(animator);
       }
     }
     for (Animator animator : animatorsToRemove) {
       animators.remove(animator);
     }
     animatorsToRemove.clear();
   }
 }
 @SuppressWarnings("unused")
 public void addAndStartAnimator(Animator anim) {
   anim.setSprite(this);
   animators.add(anim);
 }