Game Base

Base classes for game development. Low overhead, high performance.

Ticker

Ticker allows scheduling update and render functions to fire on every animation frame in definite order to avoid layout thrashing and unnecessary style recalculations.

In the update phase, all functions should only read properties and attributes from the DOM without modifying it. Instead, these changes should be collected and flushed within the render phase. This enables the browser to only do one style and layout recalculation and one paint on every frame.

Phases available to register listeners for are executed in the following order:

• head (cleared after every frame)
• update
• render
• tail (cleared after every frame)

Example

import { Ticker } from "game-base";

const ticker = new Ticker();

const div = document.querySelector("#some-div")! as HTMLDivElement;

let w = 0;
let h = 0;

const onUpdate = () => {
  const rect = div.getBoundingClientRect();
  w = rect.width;
  h = rect.heigth;
};

const onRender = () => {
  rect.style.background = `rgb(${w % 256}, ${h % 256}, 0)`;
  rect.textContent = `${w} × ${h}`;
};

ticker.register(onUpdate, "update");
ticker.register(onRender, "render");

// the listeners will not fire until ticker is started
ticker.start();

API

All listeners should be of type (delta: number) => void. delta is the number of milliseconds passed since the last animation frame.

When starting Ticker all registered listeners will be called with delta = 0.

Ticker will ignore errors thrown by each listener and continue with execution. Errors will be logged to the console.

| method | description | | ------------------------------ | ------------------------------------------------------------------------------------------------------------------ | | register(listener, phase?) | Registers a function to run in the given phase. Defaults to render. | | unregister(listener, phase?) | Unregisters a function that runs in the given phase. Defaults to render. | | start() | Starts the ticker. It immediately fires all listeners with delta = 0 and registers with requestAnimationFrame. | | stop() | Stops the ticker by unregistering the next requestAnimationFrame. | | running | A boolean representing the ticker's running state. | | phases | A dictionary of Set<Listener>s containing all of the registered listeners. |