using System.Collections;
using System.Collections.Generic;
using UnityEngine;

/// <summary>
/// FPS 顯示于OnGUI 
/// </summary>
public class FPSOnGUIText : MonoBehaviour {

 float updateInterval = 1.0f;   //當前時間間隔
 private float accumulated = 0.0f;  //在此期間累積 
 private float frames = 0;    //在間隔內繪制的幀 
 private float timeRemaining;   //當前間隔的剩余時間
 private float fps = 15.0f;    //當前幀 Current FPS
 private float lastSample;

 void Start()
 {
  DontDestroyOnLoad(this.gameObject); //不銷毀此游戲對象，在哪個場景都可以顯示，，不需要則注釋
  timeRemaining = updateInterval;
  lastSample = Time.realtimeSinceStartup; //實時自啟動
 }
 
 void Update()
 {
  ++frames;
  float newSample = Time.realtimeSinceStartup;
  float deltaTime = newSample - lastSample;
  lastSample = newSample;
  timeRemaining -= deltaTime;
  accumulated += 1.0f / deltaTime;
 
  if (timeRemaining <= 0.0f)
  {
   fps = accumulated / frames;
   timeRemaining = updateInterval;
   accumulated = 0.0f;
   frames = 0;
  }
 }

 void OnGUI()
 {
  GUIStyle style = new GUIStyle
  {
   border = new RectOffset(10, 10, 10, 10),
   fontSize = 50,
   fontStyle = FontStyle.BoldAndItalic,   
  };
  //自定義寬度 ，高度大小 顏色，style
  GUI.Label(new Rect(Screen.width/2-50, Screen.height - 100, 200, 200), "<color=#00ff00><size=30>" + "FPS:" + fps.ToString("f2")+ "</size></color>", style);
 }
}