timer — Scheduling updates

Kate updates its internal state at a maximum of 30 FPS, regardless of the host device capabilities. This is, however, synchronised with the device’s refresh rate and the browser’s rendering loop.

The Timer API provides a single event, emitted whenever the emulator is ready to refresh. All listeners of the event are called synchronously and expected to run to completion during that call. That is, you should not have asynchronous processes spawning (e.g.: by using promises) from your listener function, as that will cause the code to run without any synchronisation, and the behaviour of querying the Kate emulator state will thus be unpredictable.

property KateAPI.timer.on_tick: EventStream[number]

Emitted whenever Kate is ready to refresh. The data in this event is a monotonic timestamp, which you can then use to calculate how much time has passed since your update function was previously called.

property KateAPI.timer.fps: number

The current estimated number of frames the game is running at. Can be useful for debugging performance issues with your game’s loop.