private void OnFulcrumHover(FulcrumBehaiver fulcrum)
 {
     if (onFulcrumHover != null)
     {
         onFulcrumHover.Invoke(fulcrum);
     }
 }
 private void OnFulcrumClicked(FulcrumBehaiver fulcrum)
 {
     if (onFulcrumClicked != null)
     {
         onFulcrumClicked.Invoke(fulcrum);
     }
 }
 internal void RegistFulcrum(FulcrumBehaiver fulcrum)
 {
     if (!this.fulcrums.Contains(fulcrum))
     {
         fulcrum.onHover   = OnFulcrumHover;
         fulcrum.onClicked = OnFulcrumClicked;
         this.fulcrums.Add(fulcrum);
     }
 }