unity实现摄像头跟随

using UnityEngine;using System.Collections; public class FllowTarget : MonoBehaviour {   public Transform character;  //摄像机要跟随的人物  public float smoothTime = 0.01f; //摄像机平滑移动的时间  private Vector3 cameraVelocity = Vector3.zero;  private Camera mainCamera; //主摄像机（有时候会在工程中有多个摄像机，但是只能有一个主摄像机吧）    void Awake ()   {    mainCamera = Camera.main;  }   void Update()  {    transform.position = Vector3.SmoothDamp(transform.position, character.position + new Vector3(0, 0, -5), ref cameraVelocity, smoothTime);  }  }