【Unity3D自学记录】Unity3D显示NPC名称

using UnityEngine;
using System.Collections;

public class NPCName : MonoBehaviour {
//主角对象
private GameObject player;
//主摄像机对象
private Camera camera;
//NPC名称
private string name = "我是NPC";

void Start()
{
//根据Tag得到主角对象
player = GameObject.FindGameObjectWithTag("MainCamera");
camera = Camera.main;
}

void OnGUI()
{
//得到NPC头顶在3D世界中的坐标
Vector3 worldPosition = new Vector3(transform.position.x, transform.position.y + 0.5f, transform.position.z);
//根据NPC头顶的3D坐标换算成它在2D屏幕中的坐标
Vector2 position = camera.WorldToScreenPoint(worldPosition);
//得到真实NPC头顶的2D坐标
position = new Vector2(position.x, Screen.height - position.y);
//计算NPC名称的宽高
Vector2 nameSize = GUI.skin.label.CalcSize(new GUIContent(name));
//设置显示颜色为黄色
GUI.color = Color.red;
//绘制NPC名称
GUI.Label(new Rect(position.x - (nameSize.x / 2), position.y - nameSize.y, nameSize.x, nameSize.y), name);

}
}