JoyStone.cs

using UnityEngine;
using System.Collections;

public class JoyStone : MonoBehaviour 
{
	#region Field
	public int coinValue;
	private Vector3 heroPosition;
	//private Hero hero;
	private Vector3 selfPosition;
	private Vector3 distanceToHero;
	private float distanceToHeroSqrf;
	public float moneySuckRange;
	public float jstoneMovingSpeed;
	private float moneySuckRangeSqr;
	public GameObject hero;
	#endregion

	// Use this for initialization
	void Start () 
	{
		hero = GameObject.Find("Hero");
			//.GetComponent("Hero");
		selfPosition = new Vector3 (transform.position.x, 0, transform.position.z);
		moneySuckRangeSqr = moneySuckRange * moneySuckRange;
	}
	
	// money suck
	void Update () 
	{
		heroPosition = new Vector3 ( hero.gameObject.transform.position.x, 0, hero.gameObject.transform.position.z);
		distanceToHero = heroPosition - selfPosition;
		distanceToHeroSqrf = distanceToHero.sqrMagnitude;
		if( distanceToHeroSqrf <= moneySuckRangeSqr)
		{
			float amtToMove = jstoneMovingSpeed * Time.deltaTime;
			transform.Translate( (heroPosition - selfPosition) * amtToMove,Space.World);
		}
	}
	//when collide with player call player addscore func to gain score
	void OnTriggerEnter(Collider otherObject)
	{
		//Debug.Log ("got hit");

		if (otherObject.tag == "Player")
		{
			otherObject.gameObject.SendMessage("heroGotCoin",coinValue);
			Destroy(this.gameObject);
		}
	}
}