@debuffjp/juice

Game-feel building blocks: tweens, easing, pooled particles, trails and squash-and-stretch. No dependencies, and each export can be used on its own.

import { Particles, squash, Tweens } from "@debuffjp/juice";

const tweens = new Tweens();
const particles = new Particles(() => game.random.next()); // seeded, so captures are reproducible

// on impact
squash(tweens, player, 0.35);
particles.emit({ x, y, count: 16, colors: ["#ffd166", "#ef476f"], gravity: 200 });
game.camera.shake(0.3);
game.freeze(0.06); // hit-stop

// every step
tweens.update(dt);
particles.update(dt);

API

• Tweens: to(target, props, { duration, ease, delay, yoyo, repeat, onComplete }) → { done, cancel(), finished }, kill(target), update(dt)
• ease: linear, in/out/inOutQuad, in/out/inOutCubic, outBack, outElastic, outBounce
• Particles: emit({ x, y, count, speed, angle, spread, life, size, sizeEnd, colors, gravity, drag, shape, additive }), update(dt), draw(draw), clear()
• Trail: push(x, y), draw(draw), clear()
• squash(tweens, target, amount?, duration?): replaces only the scale tweens on target, so a move or fade on it keeps running. Before 0.8 it stopped every tween on the target.