//====================================================================================
//
// Purpose: Provide GUI view of the current frames per second in the game
//
// This script must be attached to a Text element within a Canvas that has the
// Render Mode set to "Screen Space - Camera" and the Render Camera set to the
// [CameraRig]-> Camera (head) -> Camera (eye) object with a plane distance of 0.1.
//
// This script is pretty much a copy and paste from the script at:
// http://talesfromtherift.com/vr-fps-counter/
//
// So all credit to Peter Koch for his work. Twitter: @peterept
//
//====================================================================================

using UnityEngine;
using UnityEngine.UI;

public class FramsPerSecondViewer : MonoBehaviour {
    public bool displayFPS = true;
    public int targetFPS = 90;
    public int fontSize = 32;
    public Vector3 position = Vector3.zero;
    public Color goodColor = Color.green;
    public Color warnColor = Color.yellow;
    public Color badColor = Color.red;

    private const float updateInterval = 0.5f;
    private int framesCount;
    private float framesTime;
    private Text text;

    void Start()
    {
        text = this.GetComponent<Text>();
        text.fontSize = fontSize;
        text.transform.localPosition = position;
    }

    void Update()
    {
        framesCount++;
        framesTime += Time.unscaledDeltaTime;

        if (framesTime > updateInterval)
        {
            if (text != null)
            {
                if (displayFPS)
                {
                    float fps = framesCount / framesTime;
                    text.text = System.String.Format("{0:F2} FPS", fps);
                    text.color = (fps > (targetFPS - 5) ? goodColor :
                                 (fps > (targetFPS - 30) ? warnColor :
                                  badColor));
                }
                else
                {
                    text.text = "";
                }
            }
            framesCount = 0;
            framesTime = 0;
        }
    }
}