Games are updated in discrete intervals. Knowing that, we can count time pretty easily. Assuming our game runs at 60 fps, we can do something like this...
int timer = 120; // Frames.
...
timer -= 1;
if (timer == 0)
DoTheThing();...and get a decent timer.
But there is a big problem: it fully depends on the game's fps. What if we want to have dynamic fps or time scaling? Then we will have to use deltatime. Deltatime is essentially just a variable which tells how much time has passed since the previous frame.
So now our timer will look like this:
int timer = 2; // Seconds.
...
timer -= dt;
if (timer <= 0)
DoTheThing();Now let's wrap dt into a nice class, and we got a TimeKeeper!
TimeKeeper has two purposes:
- Tell you how much time it is.
- Deceive you.
Time-telling part is pretty straightforward. Let's rewrite the code above once again to use TimeKeeper.
int timer = 2; // Seconds.
TimeKeeper _keeper = new TimeKeeper();
...
timer -= _keeper.Time();
if (timer <= 0)
DoTheThing();You can also do speeds with it.
var movementSpeed = 100; // 100 pixels per second.
x += TimeKeeper.Global.Time(movementSpeed); // Speed will be automatically multiplied by the delta time.
// NOTE: Here we've used a static TimeKeeper.Global, which is a regular TimeKeeper instance, just created by the engine for conveniency.And now, the main reason why you should use TimeKeeper. The deceiving.
TimeKeeper has a property named TimeMultiplier, which can trick your stuff into running faster or slower.
int timer = 2; // Seconds.
TimeKeeper _keeper = new TimeKeeper();
_keeper.TimeMultiplier = 0.5; // Now the timer will run for 4 seconds before firing.You can have several time keepers to slow down some parts of the game, but keep others at normal speed. Can you feel the power that gives you?! :0
So yeah, I do recommend using TimeKeeper even if you have fixed fps.