u3d fpsCounter

因为u3d自己的stats下面的fpscounter不是实际意义上的fps，所以看到demo的fpsCounter，把它改写为c#的

using UnityEngine;
using System.Collections;

public class FpsCounterex : MonoBehaviour
{
    private GUIText guitex;
    private double updateInterval = 1.0f;
    private double lastInterval;
    private int frames = 0;

    // Use this for initialization
    void Start ()
    {
        lastInterval = Time.realtimeSinceStartup;
        frames = 0;
    }

    void Exit()
    {
        if (guiText)
            DestroyImmediate(guiText.gameObject);
    
    
    }
    void OnDisable()
    {
        if (guiText)
            DestroyImmediate(guiText.gameObject);
    }
    // Update is called once per frame
    void Update ()
    {
        ++frames;
        float timeNow = Time.realtimeSinceStartup;
        if (timeNow > lastInterval + updateInterval)
        {
            if (!guitex)
            {
               GameObject go= new GameObject("FPS Display");
               go.AddComponent("GUIText");
              // go.hideFlags = HideFlags.HideAndDontSave;
               go.transform.position =new  Vector3(0,0,0);
               guitex = go.guiText;
               guitex.pixelOffset =new  Vector2(5,55);
            }
            float fps=(float) frames /(float) (timeNow - lastInterval);
            float ms  = 1000.0f / Mathf.Max((float)fps, 0.00001f);
            guitex.text = ms.ToString("f1") + "ms " + fps.ToString("f6") + "FPS";
           // guitex.text = "abasdfasdfadsf";
            frames = 0;
            lastInterval = timeNow;
        }

       // guitex.text = "asdfasdfadsfas";
    }
}

代码放到gameobject下面，界面会自己现实fps