Adventures in Unity – 2.6 Pause & Resume


Whenever a bonus is collected a message box is displayed and the game pauses momentarily.

It’s not a function of the game I particularly like; and I probably wouldn’t use it in the final release – But, since the point of this project is to try things out & help me learn Unity, I figured I’d try and replicate it anyway.


When displaying the message box, the entire game should pause – including problematic functions like particles/physics/etc.. things controlled by the Unity engine.

Google found me a solution pretty quickly – Time.timeScale

To freeze the game set Time.timeScale = 0 – To resume the game set Time.timeScale = 1.

Time.timeScale is a float variable.
Every loop, Unity multiplies Time.deltaTime against Time.timeScale.
This determines the speed of the game – For anything that references Time.deltaTime – Any update that doesn’t reference Time.deltaTime will be unaffected (Though you really should be using Time.deltaTime).

It’s usually used to pause games & tends to be set with values 0 or 1.
Though it can be used to dynamically slow/speed up gameplay – values higher than 1 may legally require that yakety sax be played at all times.

With everything paused; the next problem was how to animate the message box – (fade in, display for x seconds, fade out).

I can run the animation without using Time.DeltaTime – But then I won’t receive any of the benefits.

Another quick google search identified the solution – A homebrew Time.deltaTime using replacement using Time.realtimeSinceStartup.

Unity documentation explains ‘realtimeSinceStartup returns the time since startup, not affected by Time.timeScale. realtimeSinceStartup also keeps increasing while the player is paused (in the background). Using realtimeSinceStartup is useful when you want to pause the game by setting Time.timeScale to zero, but still want to be able to measure time somehow.

I use The replacement Time.deltaTime as a timer;

  IEnumerator PauseTimer(float delay)

     float start = Time.realtimeSinceStartup;
     timerComplete = false;

     while (Time.realtimeSinceStartup < start + delay)
          yield return null;

     timerComplete = true;



Next Post: 2.7 Mesh Fade

Last post: 2.5b Palette Shift

Contents page.


One Reply to “Adventures in Unity – 2.6 Pause & Resume”

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s