09위에서 떨어져 튕기며 쌓이는 낙하 벽돌
카드마다 목표 열의 높이까지 중력으로 낙하하고, 닿는 순간 반발 계수로 튕긴 뒤 세로로 눌렸다 펴지며 정지해 쌓이는 느낌이 난다.
쓰임로딩 직후 등장 연출
GRAVITYBOUNCESQUASHDROP_DELAY

<main class="stage">
<div class="mr is-demo" id="mr" data-demo="1">
<div class="mr__bar">
<div class="mr__btns"><button class="mr__btn" type="button" data-r="again">섞어서 다시</button></div>
<p class="mr__live" data-r="live" aria-live="off" aria-atomic="true"><span class="mr__k">쌓인 카드</span> <b data-r="rest">0</b></p>
</div>
<div class="mr__wall" data-r="wall"></div>
</div>
</main>@use "../../../../site/static/demo-tokens" as *;
// 핵심: 중력으로 떨어져 반발 계수로 튕기고 닿는 속도만큼 눌렸다 펴지며 쌓인다. 배치는 JS 가 계산하고 CSS 는 모양만 맡는다.
@include stage($stage-ink);
$fg: $subject-cream;
$mute: $tick-mute;
$btn-bg: rgba($subject-cream, .14);
$wall-bg: rgba($subject-cream, .06);
$focus: $subject-pink;
$on: $stage-ink;
.mr {
position: relative;
box-sizing: border-box;
width: min(100%, 440px);
height: min(252px, calc(100vh - 2 * clamp(8px, 4vw, 24px)));
display: flex;
flex-direction: column;
gap: $sp-2;
color: $fg;
font-size: 12px;
line-height: 16px;
font-weight: 600;
user-select: none;
}
.mr b { font-weight: 800; font-variant-numeric: tabular-nums; }
.mr__bar {
display: flex;
flex-wrap: wrap;
align-items: center;
justify-content: space-between;
gap: $sp-2;
min-height: 28px;
}
.mr__btns {
display: flex;
flex-wrap: wrap;
gap: $sp-1;
}
.mr__btn {
box-sizing: border-box;
min-width: 28px;
height: 28px;
padding: 0 $sp-3;
border: 0;
border-radius: $r-pill;
background: $btn-bg;
color: $fg;
font-size: 12px;
line-height: 16px;
font-weight: 700;
white-space: nowrap;
cursor: pointer;
}
.mr__btn[aria-pressed="true"] { background: $fg; color: $on; }
.mr__btn:focus-visible { outline: 3px solid $focus; outline-offset: 2px; }
.mr__live { margin: 0; color: $mute; white-space: nowrap; }
.mr__live b { color: $fg; }
.mr__wall {
position: relative;
flex: 1 1 auto;
min-height: 0;
overflow: hidden;
border-radius: $r-card;
background: $wall-bg;
}
.mr__card {
position: absolute;
left: 0;
top: 0;
box-sizing: border-box;
overflow: hidden;
border-radius: $r-sm;
background: linear-gradient(150deg, $subject-lilac, $subject-pink);
color: $subject-ink;
will-change: transform;
box-shadow: 0 calc(2px + var(--lift, 0) * 10px) calc(6px + var(--lift, 0) * 14px) rgba($subject-ink, .22);
}
.mr__card::after {
content: "";
position: absolute;
inset: 0;
background: linear-gradient(135deg, rgba($stage-paper, .45), rgba($stage-paper, 0) 55%);
pointer-events: none;
}
.mr__card[data-c="1"] { background: linear-gradient(150deg, $subject-sky, $subject-mint); }
.mr__card[data-c="2"] { background: linear-gradient(150deg, $subject-mint, $subject-lilac); }
.mr__card[data-c="3"] { background: linear-gradient(150deg, $subject-sky, $subject-lilac); }
.mr__card[data-c="4"] { background: linear-gradient(150deg, $subject-pink, $subject-lilac); }
.mr__card[data-c="5"] { background: linear-gradient(150deg, $subject-mint, $subject-sky); }
.mr__card i {
position: absolute;
left: $sp-2;
top: $sp-1;
font-style: normal;
font-size: 12px;
line-height: 16px;
font-weight: 800;
z-index: 1;
opacity: .85;
}
.mr__card { transform-origin: 50% 100%; }
.mr__mark {
position: absolute;
left: 0;
top: 0;
height: $sp-1;
border-radius: $r-pill;
background: rgba($fg, .3);
z-index: 3;
pointer-events: none;
}
.mr__mark[data-low] { background: $subject-mint; }
@media (prefers-reduced-motion: reduce) {
.mr__cursor, .mr__ring { display: none; }
.mr__card { will-change: auto; }
}html, body {
margin: 0;
overflow: hidden;
}
.stage {
box-sizing: border-box;
min-height: 100vh;
display: grid;
place-items: center;
margin: 0;
background: #17141a;
font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
padding: clamp(8px, 4vw, 24px);
}
.mr {
position: relative;
box-sizing: border-box;
width: min(100%, 440px);
height: min(252px, 100vh - 2 * clamp(8px, 4vw, 24px));
display: flex;
flex-direction: column;
gap: 8px;
color: #fff7e6;
font-size: 12px;
line-height: 16px;
font-weight: 600;
user-select: none;
}
.mr b {
font-weight: 800;
font-variant-numeric: tabular-nums;
}
.mr__bar {
display: flex;
flex-wrap: wrap;
align-items: center;
justify-content: space-between;
gap: 8px;
min-height: 28px;
}
.mr__btns {
display: flex;
flex-wrap: wrap;
gap: 4px;
}
.mr__btn {
box-sizing: border-box;
min-width: 28px;
height: 28px;
padding: 0 12px;
border: 0;
border-radius: 999px;
background: rgba(255, 247, 230, 0.14);
color: #fff7e6;
font-size: 12px;
line-height: 16px;
font-weight: 700;
white-space: nowrap;
cursor: pointer;
}
.mr__btn[aria-pressed=true] {
background: #fff7e6;
color: #17141a;
}
.mr__btn:focus-visible {
outline: 3px solid #ff9ebb;
outline-offset: 2px;
}
.mr__live {
margin: 0;
color: #9a93a6;
white-space: nowrap;
}
.mr__live b {
color: #fff7e6;
}
.mr__wall {
position: relative;
flex: 1 1 auto;
min-height: 0;
overflow: hidden;
border-radius: 16px;
background: rgba(255, 247, 230, 0.06);
}
.mr__card {
position: absolute;
left: 0;
top: 0;
box-sizing: border-box;
overflow: hidden;
border-radius: 8px;
background: linear-gradient(150deg, #b9a0ff, #ff9ebb);
color: #17141a;
will-change: transform;
box-shadow: 0 calc(2px + var(--lift, 0) * 10px) calc(6px + var(--lift, 0) * 14px) rgba(23, 20, 26, 0.22);
}
.mr__card::after {
content: "";
position: absolute;
inset: 0;
background: linear-gradient(135deg, rgba(255, 255, 255, 0.45), rgba(255, 255, 255, 0) 55%);
pointer-events: none;
}
.mr__card[data-c="1"] {
background: linear-gradient(150deg, #6ec8ff, #4cd4a6);
}
.mr__card[data-c="2"] {
background: linear-gradient(150deg, #4cd4a6, #b9a0ff);
}
.mr__card[data-c="3"] {
background: linear-gradient(150deg, #6ec8ff, #b9a0ff);
}
.mr__card[data-c="4"] {
background: linear-gradient(150deg, #ff9ebb, #b9a0ff);
}
.mr__card[data-c="5"] {
background: linear-gradient(150deg, #4cd4a6, #6ec8ff);
}
.mr__card i {
position: absolute;
left: 8px;
top: 4px;
font-style: normal;
font-size: 12px;
line-height: 16px;
font-weight: 800;
z-index: 1;
opacity: 0.85;
}
.mr__card {
transform-origin: 50% 100%;
}
.mr__mark {
position: absolute;
left: 0;
top: 0;
height: 4px;
border-radius: 999px;
background: rgba(255, 247, 230, 0.3);
z-index: 3;
pointer-events: none;
}
.mr__mark[data-low] {
background: #4cd4a6;
}
@media (prefers-reduced-motion: reduce) {
.mr__cursor, .mr__ring {
display: none;
}
.mr__card {
will-change: auto;
}
}(function () {
const root = document.getElementById("mr");
const CLS = { card: "mr__card" };
const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
let demo = !reduce;
let raf = 0;
let last = -1;
let ready = false;
const offs = [];
function q(sel) {
return root.querySelector(sel);
}
const wall = q("[data-r=wall]");
const live = q("[data-r=live]");
function clamp(v, lo, hi) {
return Math.max(lo, Math.min(hi, v));
}
function makeRng(seed) {
let s = seed >>> 0;
return function () {
s = (Math.imul(s, 1664525) + 1013904223) >>> 0;
return s / 4294967296;
};
}
function on(el, type, fn) {
el.addEventListener(type, fn);
offs.push(function () {
el.removeEventListener(type, fn);
});
}
function stopDemo() {
if (!demo) return;
demo = false;
root.removeAttribute("data-demo");
root.classList.remove("is-demo");
live.setAttribute("aria-live", "polite");
}
if (reduce) live.setAttribute("aria-live", "polite");
// 카드: 시드 LCG 로 비율을 뽑는다. 이미지 파일은 없고 그라디언트와 번호만 있다.
function makeCards(n, seed, lo, hi) {
const rng = makeRng(seed);
const list = [];
for (let i = 0; i < n; i += 1) {
const el = document.createElement("div");
el.className = CLS.card;
el.setAttribute("data-c", String(i % 6));
el.innerHTML = "<i>" + (i + 1) + "</i>";
wall.appendChild(el);
list.push({
el: el, ratio: lo + rng() * (hi - lo), cat: Math.floor(rng() * 3),
x: 0, y: 0, w: 0, h: 0, tx: 0, ty: 0, tw: 0, th: 0,
s: 1, ds: 1, o: 1, dop: 1, vx: 0, vy: 0,
ox: 0, oy: 0, osx: 0, osy: 0, ovx: 0, ovy: 0, ovsx: 0, ovsy: 0,
fx: 0, fy: 0, fs: 1, fo: 1, t0: 0, sq: 0, rest: 0, wait: 0
});
}
return list;
}
function colW(cols, gap) {
return (wall.clientWidth - gap * (cols - 1)) / cols;
}
// 최단 열 배치: 카드를 순서대로 읽으며 지금 가장 낮은 열 끝에 얹고 그 열 높이에 카드 높이와 간격을 더한다.
function pack(hs, cols, cw, gap) {
const colH = [];
for (let k = 0; k < cols; k += 1) colH.push(0);
const out = [];
for (let i = 0; i < hs.length; i += 1) {
let best = 0;
for (let k = 1; k < cols; k += 1) {
if (colH[k] < colH[best] - 0.5) best = k;
}
out.push({ x: best * (cw + gap), y: colH[best] });
colH[best] += hs[i] + gap;
}
return out;
}
function put(c, x, y, sx, sy) {
const st = c.el.style;
st.width = c.w.toFixed(1) + "px";
st.height = c.h.toFixed(1) + "px";
st.transform = "translate3d(" + x.toFixed(2) + "px," + y.toFixed(2) + "px,0) scale(" + sx.toFixed(3) + "," + sy.toFixed(3) + ")";
}
function frame(ts) {
const dt = last < 0 ? 0.016 : Math.min(0.05, (ts - last) / 1000);
last = ts;
if (demo) script(ts);
step(dt, ts);
render();
raf = requestAnimationFrame(frame);
}
const ro = new ResizeObserver(function () {
relayout();
});
ro.observe(root);
// 기법: 카드마다 중력 가속으로 떨어지다가 목표 높이에 닿으면 속도를 -BOUNCE 배로 뒤집고, 닿는 속도에 비례해 세로로 눌렸다가 펴진다.
const GRAVITY = 2600;
const BOUNCE = 0.32;
const SQUASH = 0.8;
const DROP_DELAY = 140;
const COLUMNS = 3;
const GAP = 8;
const COUNT = 9;
const cards = makeCards(COUNT, 21, 0.22, 0.48);
const restEl = q("[data-r=rest]");
let seed = 21;
let startAt = -1;
let restNow = -1;
function reset(now) {
startAt = now;
for (let i = 0; i < cards.length; i += 1) {
const c = cards[i];
c.y = -c.h - 24;
c.x = c.tx;
c.vy = 0;
c.sq = 0;
c.rest = 0;
}
showRest();
}
function showRest() {
let n = 0;
for (let i = 0; i < cards.length; i += 1) n += cards[i].rest;
const shown = n === cards.length ? n : 0;
if (shown !== restNow) {
restNow = shown;
restEl.textContent = String(shown);
}
}
function reroll() {
seed += 1;
const rng = makeRng(seed);
for (let i = 0; i < cards.length; i += 1) cards[i].ratio = 0.22 + rng() * 0.26;
relayout();
}
function relayout() {
const cw = colW(COLUMNS, GAP);
const hs = cards.map(function (c) {
return c.ratio * cw;
});
const at = pack(hs, COLUMNS, cw, GAP);
for (let i = 0; i < cards.length; i += 1) {
const c = cards[i];
c.w = cw;
c.h = hs[i];
c.tx = at[i].x;
c.ty = at[i].y;
c.x = c.tx;
if (c.rest === 1 || reduce) {
c.y = c.ty;
c.rest = 1;
}
}
if (!ready) {
if (reduce) {
for (let i = 0; i < cards.length; i += 1) cards[i].rest = 1;
} else {
reset(performance.now());
}
}
ready = true;
showRest();
if (reduce) render();
}
function script(ts) {
const base = Math.floor(ts / 2000) * 2000 + 100;
if (base !== startAt) reset(base);
}
function step(dt, ts) {
const n = Math.max(1, Math.ceil(dt / (1 / 120)));
const h = dt / n;
for (let s = 0; s < n; s += 1) {
for (let i = 0; i < cards.length; i += 1) {
const c = cards[i];
c.sq *= Math.exp(-14 * h);
if (c.rest === 1 || ts - startAt < i * DROP_DELAY) continue;
c.vy += GRAVITY * h;
c.y += c.vy * h;
if (c.y >= c.ty) {
const hit = c.vy;
c.y = c.ty;
if (hit > 90) {
c.vy = -hit * BOUNCE;
c.sq = Math.max(c.sq, Math.min(0.3, (SQUASH * hit) / 4200));
} else {
c.vy = 0;
c.rest = 1;
}
}
}
}
showRest();
}
function render() {
for (let i = 0; i < cards.length; i += 1) {
const c = cards[i];
put(c, c.x, c.y, 1 + c.sq * 0.45, 1 - c.sq);
}
}
on(q("[data-r=again]"), "click", function () {
stopDemo();
reroll();
if (!reduce) reset(performance.now());
});
relayout();
if (reduce) {
render();
} else {
raf = requestAnimationFrame(frame);
}
})();// GravityDropStack - vanilla 판(09-mr-gravity-drop-stack) 의 React 포트. 같은 계산을 useEffect 안에서 돌린다.
import { useEffect, useRef } from "react";
import styles from "./GravityDropStack.module.scss";
type Card = {
el: HTMLElement; ratio: number; cat: number;
x: number; y: number; w: number; h: number; tx: number; ty: number; tw: number; th: number;
s: number; ds: number; o: number; dop: number; vx: number; vy: number;
ox: number; oy: number; osx: number; osy: number; ovx: number; ovy: number; ovsx: number; ovsy: number;
fx: number; fy: number; fs: number; fo: number; t0: number; sq: number; rest: number; wait: number;
};
export default function GravityDropStack() {
const rootRef = useRef<HTMLDivElement | null>(null);
useEffect(() => {
const rootEl = rootRef.current;
if (!rootEl) return;
const root: HTMLElement = rootEl;
const CLS = { card: styles["mr__card"] };
const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
let demo = !reduce;
let raf: number = 0;
let last: number = -1;
let ready = false;
const offs: Array<() => void> = [];
function q(sel: string): HTMLElement {
return root.querySelector(sel) as HTMLElement;
}
const wall = q("[data-r=wall]");
const live = q("[data-r=live]");
function clamp(v: number, lo: number, hi: number): number {
return Math.max(lo, Math.min(hi, v));
}
function makeRng(seed: number): () => number {
let s = seed >>> 0;
return function (): number {
s = (Math.imul(s, 1664525) + 1013904223) >>> 0;
return s / 4294967296;
};
}
function on(el: EventTarget, type: string, fn: (e: any) => void): void {
el.addEventListener(type, fn);
offs.push(function (): void {
el.removeEventListener(type, fn);
});
}
function stopDemo(): void {
if (!demo) return;
demo = false;
root.removeAttribute("data-demo");
root.classList.remove("is-demo");
live.setAttribute("aria-live", "polite");
}
if (reduce) live.setAttribute("aria-live", "polite");
// 카드: 시드 LCG 로 비율을 뽑는다. 이미지 파일은 없고 그라디언트와 번호만 있다.
function makeCards(n: number, seed: number, lo: number, hi: number): Card[] {
const rng = makeRng(seed);
const list: Card[] = [];
for (let i = 0; i < n; i += 1) {
const el = document.createElement("div");
el.className = CLS.card;
el.setAttribute("data-c", String(i % 6));
el.innerHTML = "<i>" + (i + 1) + "</i>";
wall.appendChild(el);
list.push({
el: el, ratio: lo + rng() * (hi - lo), cat: Math.floor(rng() * 3),
x: 0, y: 0, w: 0, h: 0, tx: 0, ty: 0, tw: 0, th: 0,
s: 1, ds: 1, o: 1, dop: 1, vx: 0, vy: 0,
ox: 0, oy: 0, osx: 0, osy: 0, ovx: 0, ovy: 0, ovsx: 0, ovsy: 0,
fx: 0, fy: 0, fs: 1, fo: 1, t0: 0, sq: 0, rest: 0, wait: 0
});
}
return list;
}
function colW(cols: number, gap: number): number {
return (wall.clientWidth - gap * (cols - 1)) / cols;
}
// 최단 열 배치: 카드를 순서대로 읽으며 지금 가장 낮은 열 끝에 얹고 그 열 높이에 카드 높이와 간격을 더한다.
function pack(hs: number[], cols: number, cw: number, gap: number): Array<{ x: number; y: number }> {
const colH: number[] = [];
for (let k = 0; k < cols; k += 1) colH.push(0);
const out: Array<{ x: number; y: number }> = [];
for (let i = 0; i < hs.length; i += 1) {
let best = 0;
for (let k = 1; k < cols; k += 1) {
if (colH[k] < colH[best] - 0.5) best = k;
}
out.push({ x: best * (cw + gap), y: colH[best] });
colH[best] += hs[i] + gap;
}
return out;
}
function put(c: Card, x: number, y: number, sx: number, sy: number): void {
const st = c.el.style;
st.width = c.w.toFixed(1) + "px";
st.height = c.h.toFixed(1) + "px";
st.transform = "translate3d(" + x.toFixed(2) + "px," + y.toFixed(2) + "px,0) scale(" + sx.toFixed(3) + "," + sy.toFixed(3) + ")";
}
function frame(ts: number): void {
const dt = last < 0 ? 0.016 : Math.min(0.05, (ts - last) / 1000);
last = ts;
if (demo) script(ts);
step(dt, ts);
render();
raf = requestAnimationFrame(frame);
}
const ro = new ResizeObserver(function (): void {
relayout();
});
ro.observe(root);
// 기법: 카드마다 중력 가속으로 떨어지다가 목표 높이에 닿으면 속도를 -BOUNCE 배로 뒤집고, 닿는 속도에 비례해 세로로 눌렸다가 펴진다.
const GRAVITY = 2600;
const BOUNCE = 0.32;
const SQUASH = 0.8;
const DROP_DELAY = 140;
const COLUMNS = 3;
const GAP = 8;
const COUNT = 9;
const cards = makeCards(COUNT, 21, 0.22, 0.48);
const restEl = q("[data-r=rest]");
let seed = 21;
let startAt = -1;
let restNow = -1;
function reset(now: number): void {
startAt = now;
for (let i = 0; i < cards.length; i += 1) {
const c = cards[i];
c.y = -c.h - 24;
c.x = c.tx;
c.vy = 0;
c.sq = 0;
c.rest = 0;
}
showRest();
}
function showRest(): void {
let n = 0;
for (let i = 0; i < cards.length; i += 1) n += cards[i].rest;
const shown = n === cards.length ? n : 0;
if (shown !== restNow) {
restNow = shown;
restEl.textContent = String(shown);
}
}
function reroll(): void {
seed += 1;
const rng = makeRng(seed);
for (let i = 0; i < cards.length; i += 1) cards[i].ratio = 0.22 + rng() * 0.26;
relayout();
}
function relayout(): void {
const cw = colW(COLUMNS, GAP);
const hs = cards.map(function (c: Card): number {
return c.ratio * cw;
});
const at = pack(hs, COLUMNS, cw, GAP);
for (let i = 0; i < cards.length; i += 1) {
const c = cards[i];
c.w = cw;
c.h = hs[i];
c.tx = at[i].x;
c.ty = at[i].y;
c.x = c.tx;
if (c.rest === 1 || reduce) {
c.y = c.ty;
c.rest = 1;
}
}
if (!ready) {
if (reduce) {
for (let i = 0; i < cards.length; i += 1) cards[i].rest = 1;
} else {
reset(performance.now());
}
}
ready = true;
showRest();
if (reduce) render();
}
function script(ts: number): void {
const base = Math.floor(ts / 2000) * 2000 + 100;
if (base !== startAt) reset(base);
}
function step(dt: number, ts: number): void {
const n = Math.max(1, Math.ceil(dt / (1 / 120)));
const h = dt / n;
for (let s = 0; s < n; s += 1) {
for (let i = 0; i < cards.length; i += 1) {
const c = cards[i];
c.sq *= Math.exp(-14 * h);
if (c.rest === 1 || ts - startAt < i * DROP_DELAY) continue;
c.vy += GRAVITY * h;
c.y += c.vy * h;
if (c.y >= c.ty) {
const hit = c.vy;
c.y = c.ty;
if (hit > 90) {
c.vy = -hit * BOUNCE;
c.sq = Math.max(c.sq, Math.min(0.3, (SQUASH * hit) / 4200));
} else {
c.vy = 0;
c.rest = 1;
}
}
}
}
showRest();
}
function render(): void {
for (let i = 0; i < cards.length; i += 1) {
const c = cards[i];
put(c, c.x, c.y, 1 + c.sq * 0.45, 1 - c.sq);
}
}
on(q("[data-r=again]"), "click", function (): void {
stopDemo();
reroll();
if (!reduce) reset(performance.now());
});
relayout();
if (reduce) {
render();
} else {
raf = requestAnimationFrame(frame);
}
return () => {
cancelAnimationFrame(raf);
offs.forEach((f) => f());
ro.disconnect();
};
}, []);
return (
<main className={styles["stage"]}>
<div ref={rootRef} className={styles["mr"] + " is-demo"} data-demo="1">
<div className={styles["mr__bar"]}>
<div className={styles["mr__btns"]}><button className={styles["mr__btn"]} type="button" data-r="again">섞어서 다시</button></div>
<p className={styles["mr__live"]} data-r="live" aria-live="off" aria-atomic="true"><span className={styles["mr__k"]}>쌓인 카드</span> <b data-r="rest">0</b></p>
</div>
<div className={styles["mr__wall"]} data-r="wall"></div>
</div>
</main>
);
}09 위에서 떨어져 튕기며 쌓이는 낙하 벽돌 — 측정 누적면적 46.294% · 움직인 프레임 22/23GODRICH 원작 · zip 에 SCSS·React 포함 · css masonry layout 9가지 — 높이가 다른 카드가 빈틈없이 자리를 찾는 배열
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