@gamestdio/timer

@gamestdio/timer

Timing Events tied to colyseus/clock.

ClockTimer is a subclass of Clock, which adds methods to handle timeout and intervals relying on Clock's ticks.

Why?

Once built-in setTimeout and setInterval relies on CPU load, functions may delay an unexpected amount of time to execute. Having it tied to a clock's time is guaranteed to execute in a precise way.

Therefore there is ideally one single CPU clock for all the timers and then they are executed in sequence.

See a quote from W3C Timers Specification:

This API does not guarantee that timers will fire exactly on schedule. Delays due to CPU load, other tasks, etc, are to be expected.

It does however guarantees an order of « does this timer should execute based on elapsed time since last tick call ? » based on when they were registered.

In classic timer if we have a setInterval of 0ms it will fill the event loop timer queue with callbacks (like A LOT) and if we have another of 1000ms interval it will be executed only after many of the 0ms callbacks are executed. This is not the case with ClockTimer, as it loops through all timers and checks if they should be executed there are more chance that the 1000ms callback will be executed in time.

You can also call .tick() manually to check all the timers at once on a specific important time.

Other cool stuff is that you manage all your timers in one place and therefore you can clear all of them at once. This is useful for example when you want to clear all timers when a game is over. Or when using those is irrelevant.

API

Clock

• setInterval(handler, time, ...args) -> Delayed
• setTimeout(handler, time, ...args) -> Delayed
• duration(ms: number) -> Promise<void> - Convenience method to wait for a duration in async functions or promises. See associated JSdoc for more details.
• clear() - clear all intervals and timeouts, and throw any promise created with duration.

Delayed

• clear() -> void - Clear timeout/interval
• reset() -> void - Reset elapsed time
• active -> Boolean - Is it still active?
• pause() -> void - Pause the execution
• resume() -> void - Continue the execution
• paused -> Boolean - Is is paused?

License

MIT