Function throttle

packages/melonjs/src/utils/function.ts:37–62

(
	fn: (...args: T) => void,
	wait: number = 100,
)

 * @returns the function that will be throttled
 */
export const throttle = <T extends unknown[]>(
	fn: (...args: T) => void,
	wait: number = 100,
) => {
	let inThrottle: boolean,
		lastFn: ReturnType<typeof setTimeout>,
		lastTime: number;
	return (...args: T) => {
		if (!inThrottle) {
			fn.apply(this, args);
			lastTime = Date.now();
			inThrottle = true;
		} else {
			clearTimeout(lastFn);
			lastFn = setTimeout(
				() => {
					if (Date.now() - lastTime >= wait) {
						fn.apply(this, args);
						lastTime = Date.now();
					}
				},
				Math.max(wait - (Date.now() - lastTime), 0),
			);
		}
	};
};