/**
  * Removes a particular item from the manager. This will stop it from being updated or painted.
  *
  * @param gs The Terrain to remove
  */
 public void remove(T gs) {
   if (gs == null) {
     return;
   }
   myGameSprites.remove(gs);
   gs.setChanged();
   gs.notifyObservers("remove");
 }
 private void removeIterator(T gs) {
   myRemoval.remove();
   gs.setChanged();
   gs.notifyObservers("remove");
 }
 /**
  * Adds items to the manager. These items will then be observed by the NodeMap and will be updated
  * and painted every cycle.
  *
  * @param gs The item to add
  */
 public void add(T gs) {
   gs.addObserver(GameState.getMap().getNodeMap());
   gs.setChanged();
   gs.notifyObservers(gs.getWorldLocation());
   myGameSprites.add(gs);
 }