public void Initialize()
{
_pool.SetObjectPositionCache(new Dictionary <TilePos, List <Entity> >());
_positionableGroup = _pool.GetGroup(GameMatcher.Position);
_positionableGroup.OnEntityAdded += (g, e, i, c) => AddToCache(e, c as PositionComponent);
_positionableGroup.OnEntityRemoved += (g, e, i, c) => RemoveFromCache(e, c as PositionComponent);
}
