unity中用第三人称视角控制角色移动的方法

using UnityEngine;
using System.Collections;

public class Player : MonoBehaviour
{   private CharacterController controller;
     public int speed=10;

void Start(){
       controller=GetCompoment<CharacterController>();
}

void Update(){
controller.SimpleMove(new Vecter3(Input.GetAxis("Horizontal")*speed,0,Input.Getaxis("Vertical")*speed);
}
}