unity 游戏物体自动循环移动脚本

using UnityEngine;
using System.Collections;
public class SwanMove : MonoBehaviour {
private float moveSpeed=4; //swan的移动速度.
// Use this for initialization
void Start () {
//设置天鹅的初始位置.
transform.position=new Vector3(22,3,0);
}
// Update is called once per frame
void Update () {
if(transform.position.x>-22){
//天鹅移动.
transform.Translate(Vector3.right*-moveSpeed*Time.deltaTime);
}
else{
transform.position=new Vector3(22,3,0);
}
}
}