short helpers

lkrm.ts

// DEBUG
const _$ = console.log.bind(console);

// LKRM_STD
const $ = <T extends HTMLElement = HTMLElement>(selector: string) => document.querySelector<T>(selector);
const $$ = <T extends HTMLElement = HTMLElement>(selector: string) => document.querySelectorAll<T>(selector);

const lerp =(x: number, a: number, b: number): number => a + x * (b - a);
const { sqrt, log: ln, pow, min, max, sin, cos, tan, asin, acos, atan, atan2, PI, E } = Math;
const to_radians = (x: number) => x / 180 * PI;
const to_degrees = (x: number) => x / PI * 180;
const clamp = (x: number, minimum: number, maximum: number): number => min(max(x, minimum), maximum);
const clamp_lerp = (x: number, a: number, b: number) => lerp(clamp(x, 0, 1), a, b);
const lerp_range = (f: number, x: number, y: number, a: number, b: number) => lerp((f - x) / (y - x), a, b);
const clamp_lerp_range = (f: number, x: number, y: number, a: number, b: number) => clamp_lerp((f - x) / (y - x), a, b);

const animate = (func: (fac: number) => void, time: number) => {
    let start: number, previous_timestamp: number;

    return new Promise<void>((resolve: () => void) => window.requestAnimationFrame(function step(timestamp) {
        if (start === undefined)
            start = timestamp;
        const elapsed = timestamp - start;
    
        if (previous_timestamp !== timestamp)
            func(min(elapsed/time, 1.0));
    
        if (elapsed < time) {
            previous_timestamp = timestamp;
            window.requestAnimationFrame(step);
        }
        else
            resolve();
    }));
};