Time.realtimeSinceStartupAsDouble

Description

The real time in seconds since the game started (Read Only). Double precision version of Time.realtimeSinceStartup.

This property is the time in seconds since the start of the application and isn't constant if called multiple times in a frame. Time.timeScale doesn't affect this property. In almost all cases, use realtimeSinceStartupAsDouble over realtimeSinceStartup. realtimeSinceStartupAsDouble offers more precision, particularly over extended periods of real-world time.

In most use cases, use Time.time, Time.timeAsDouble, Time.unscaledTime, or Time.unscaledTimeAsDouble instead of this property. However, realtimeSinceStartupAsDouble is useful if you want to set timeScale to zero to pause your application, but you also still want to measure time. In Editor scripts, you can also use realtimeSinceStartupAsDouble to measure time while the Editor is paused.

realtimeSinceStartupAsDouble returns time as reported by the system timer. Depending on the platform and the hardware, it might report the same time even in several consecutive frames. If you're dividing something by time difference, take this into account (for example, time difference might become zero). On desktop, web, XR, and mobile platforms, the returned value includes time that elapsed while the system is in sleep mode. On console platforms, this behavior differs. For more information, refer to the platform-specific documentation.

NOTE: There is a known issue where realtimeSinceStartup and realtimeSinceStartupAsDouble return incorrect values when using OnDestroy@@.

using UnityEngine;
using System.Collections;

// An FPS counter.
// It calculates frames/second over each updateInterval,
// so the display does not keep changing wildly.
public class ExampleClass : MonoBehaviour
{
    public float updateInterval = 0.5F;
    private double lastInterval;
    private int frames = 0;
    private float fps;
    void Start()
    {
        lastInterval = Time.realtimeSinceStartupAsDouble;
        frames = 0;
    }

    void OnGUI()
    {
        GUILayout.Label("" + fps.ToString("f2"));
    }

    void Update()
    {
        ++frames;
        double timeNow = Time.realtimeSinceStartupAsDouble;
        if (timeNow > lastInterval + updateInterval)
        {
            fps = (float)(frames / (timeNow - lastInterval));
            frames = 0;
            lastInterval = timeNow;
        }
    }
}