第三人视角，摄像机跟随代码

using UnityEngine;
using System.Collections;

public class CameraFollow : MonoBehaviour {

	public Transform target;
	// The distance in the x-z plane to the target
	public float distance = 10.0f;
	// the height we want the camera to be above the target
	public float height = 5.0f;
	
	void LateUpdate () {
		// Early out if we don't have a target
		if (!target)
			return;
		
		// Set the position of the camera on the x-z plane to:
		// distance meters behind the target
		transform.position = target.position;
		transform.position -=  Vector3.forward * distance;
		transform.position = new Vector3(transform.position.x,transform.position.y + height,
		                                 transform.position.z);
		
		// Always look at the target
	//	transform.LookAt (target);
	}
}