04A Maze That Reopens Dead Ends to Leave Multiple Ways Through
It scans the finished maze cell by cell for dead ends and, unless a dead end falls within the keep ratio, removes one wall at its tip to splice it into a neighboring passage. At 0 no dead end survives; the higher the ratio, the more of them remain.
Best forKids' puzzles and escape-room hint boards
BRAID_KEEPDEADEND_SCAN_MSSPLICE_GLOW
<main class="stage">
<div class="hs is-demo" id="hs">
<canvas class="hs__canvas" data-role="canvas" width="480" height="300" tabindex="0" aria-label="A board that scans a finished maze cell by cell and removes the wall at each dead-end tip to join the next passage. Press to change the keep ratio"></canvas>
<p class="hs__status" data-role="status" aria-live="off">Finding dead ends and splicing them</p>
<div class="hs__tools">
<button class="hs__btn" data-role="new" type="button">New maze</button>
<button class="hs__btn" data-role="keep" type="button">Change keep ratio</button>
</div>
</div>
</main>@use "../../../../site/static/demo-tokens" as *;
@include stage($stage-ink);
.hs {
position: relative;
width: min(92vw, calc(160vh - 12.8vw));
aspect-ratio: 480 / 300;
margin: 0 auto;
border-radius: $r-card;
overflow: hidden;
box-shadow: $shadow-raised;
background: $subject-ink;
}
.hs__canvas {
display: block;
width: 100%;
height: 100%;
cursor: crosshair;
}
.hs__canvas:focus-visible {
outline: 2px solid rgba(255, 255, 255, .85);
outline-offset: -6px;
}
.hs__status {
position: absolute;
left: $sp-3;
bottom: $sp-3;
box-sizing: border-box;
max-width: 34%;
margin: 0;
padding: $sp-1 $sp-3;
border-radius: $r-control;
background: rgba(255, 255, 255, .85);
color: $subject-ink;
font-weight: 500;
font-size: 11px;
line-height: 1.4;
pointer-events: none;
}
// 판은 오른쪽에 있다 — 버튼은 왼쪽 위 칸에 두고, 좁으면 줄을 바꿔 판을 덮지 않는다
.hs__tools {
position: absolute;
left: $sp-3;
top: $sp-3;
box-sizing: border-box;
max-width: 34%;
display: flex;
flex-wrap: wrap;
gap: $sp-2;
}
.hs__btn {
margin: 0;
padding: $sp-1 $sp-3;
border: 0;
border-radius: $r-pill;
background: rgba(255, 255, 255, .85);
color: $subject-ink;
font: inherit;
font-weight: 500;
font-size: 12px;
line-height: 1.4;
cursor: pointer;
transition: background-color $dur-quick ease-out;
}
.hs__btn:hover {
background: $subject-cream;
}
.hs__btn[aria-pressed="true"] {
background: $subject-mint;
}
.hs__btn:focus-visible {
outline: 2px solid rgba(255, 255, 255, .95);
outline-offset: 2px;
}
// 손가락 가로 끌기는 이 캔버스가 받고, 세로 쓸기는 브라우저에 남겨 페이지 스크롤이 막히지 않게 한다
.hs__canvas { touch-action: pan-y; }
@media (max-width: 340px) {
.hs__btn { font-size: 10px; padding: $sp-1 $sp-2; }
.hs__status { font-size: 10px; padding: $sp-1 $sp-2; }
}
@media (prefers-reduced-motion: reduce) {
.hs__btn { transition: none; }
}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);
}
.hs {
position: relative;
width: min(92vw, 160vh - 12.8vw);
aspect-ratio: 480/300;
margin: 0 auto;
border-radius: 16px;
overflow: hidden;
box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
background: #17141a;
}
.hs__canvas {
display: block;
width: 100%;
height: 100%;
cursor: crosshair;
}
.hs__canvas:focus-visible {
outline: 2px solid rgba(255, 255, 255, 0.85);
outline-offset: -6px;
}
.hs__status {
position: absolute;
left: 12px;
bottom: 12px;
box-sizing: border-box;
max-width: 34%;
margin: 0;
padding: 4px 12px;
border-radius: 12px;
background: rgba(255, 255, 255, 0.85);
color: #17141a;
font-weight: 500;
font-size: 11px;
line-height: 1.4;
pointer-events: none;
}
.hs__tools {
position: absolute;
left: 12px;
top: 12px;
box-sizing: border-box;
max-width: 34%;
display: flex;
flex-wrap: wrap;
gap: 8px;
}
.hs__btn {
margin: 0;
padding: 4px 12px;
border: 0;
border-radius: 999px;
background: rgba(255, 255, 255, 0.85);
color: #17141a;
font: inherit;
font-weight: 500;
font-size: 12px;
line-height: 1.4;
cursor: pointer;
transition: background-color 220ms ease-out;
}
.hs__btn:hover {
background: #fff7e6;
}
.hs__btn[aria-pressed=true] {
background: #4cd4a6;
}
.hs__btn:focus-visible {
outline: 2px solid rgba(255, 255, 255, 0.95);
outline-offset: 2px;
}
.hs__canvas {
touch-action: pan-y;
}
@media (max-width: 340px) {
.hs__btn {
font-size: 10px;
padding: 4px 8px;
}
.hs__status {
font-size: 10px;
padding: 4px 8px;
}
}
@media (prefers-reduced-motion: reduce) {
.hs__btn {
transition: none;
}
}(function () {
const root = document.getElementById("hs");
if (!root) return;
const W = 480;
const H = 300;
const FIXED_DT = 16;
// 파스텔 팔레트 — 어두운 무대 위에 밝은 바닥을 얹어 명도 차로 길이 읽힌다
const BG = [29, 26, 44];
const ROCK = [44, 39, 64];
const PAPER = [255, 248, 234];
const INK = [58, 48, 76];
const MINT = [126, 226, 192];
const SKY = [124, 196, 255];
const LILAC = [190, 164, 255];
const PINK = [255, 160, 190];
const PEACH = [255, 208, 168];
function clamp(v, lo, hi) { return v < lo ? lo : (v > hi ? hi : v); }
function lerp(a, b, k) { return a + (b - a) * k; }
function smooth(x) { const c = clamp(x, 0, 1); return c * c * (3 - 2 * c); }
function rgba(c, a) {
return 'rgba(' + Math.round(c[0]) + ',' + Math.round(c[1]) + ',' + Math.round(c[2]) + ',' + clamp(a, 0, 1).toFixed(3) + ')';
}
function mix(a, b, k) { return [lerp(a[0], b[0], k), lerp(a[1], b[1], k), lerp(a[2], b[2], k)]; }
const canvasEl = root.querySelector('[data-role="canvas"]');
const statusEl = root.querySelector('[data-role="status"]');
const ctxRaw = canvasEl ? canvasEl.getContext('2d') : null;
if (!canvasEl || !ctxRaw || !statusEl) {
return;
}
const cv = canvasEl;
const ctx = ctxRaw;
const status = statusEl;
const reduceQuery = window.matchMedia('(prefers-reduced-motion: reduce)');
const still = reduceQuery.matches;
// 자동 시연 중인가 — 사람이 처음 만지는 순간 시연을 멈추고 상태 줄을 읽어 주기 시작한다
let demo = root.classList.contains('is-demo');
function wake() {
if (!demo) {
return;
}
demo = false;
root.classList.remove('is-demo');
status.setAttribute('aria-live', 'polite');
}
function say(text) {
if (status.textContent !== text) {
status.textContent = text;
}
}
function fitCanvas() {
// 배율은 2 에서 자른다 — 배율 3 기기에서 화소가 2.25배로 늘어 프레임마다 일이 그만큼 커지지 않게
const dpr = Math.min(window.devicePixelRatio || 1, 2);
cv.width = Math.round(W * dpr);
cv.height = Math.round(H * dpr);
ctx.setTransform(dpr, 0, 0, dpr, 0, 0);
}
function onResize() {
fitCanvas();
draw();
}
fitCanvas();
window.addEventListener('resize', onResize);
// 화면 좌표(CSS px) → 장면 좌표(480x300). 리사이즈 뒤에도 늘 현재 크기로 다시 잰다
function toScene(ev) {
const r = cv.getBoundingClientRect();
return [((ev.clientX - r.left) / r.width) * W, ((ev.clientY - r.top) / r.height) * H];
}
// 시드 고정 난수 — 같은 시드면 같은 미로가 다시 나온다 (32비트 정수 섞기)
function makeRng(seed) {
let s = seed >>> 0;
return function () {
s = (s + 0x6d2b79f5) >>> 0;
let t = s;
t = Math.imul(t ^ (t >>> 15), t | 1);
t ^= t + Math.imul(t ^ (t >>> 7), t | 61);
return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
};
}
// 격자 — 31×31 칸, 칸마다 벽 네 장을 비트 하나씩으로 든다
const GRID_N = 31;
const CELL_N = GRID_N * GRID_N;
const CS = 9;
const BOARD = GRID_N * CS;
let BX = W - 12 - BOARD;
const BY = (H - BOARD) / 2;
const ENTRY = 0;
const EXIT = CELL_N - 1;
// 방향 0 북 · 1 동 · 2 남 · 3 서 — 시계 방향 순서라 +1 이 오른쪽으로 돌기, +3 이 왼쪽으로 돌기
const DX = [0, 1, 0, -1];
const DY = [-1, 0, 1, 0];
const BIT = [1, 2, 4, 8];
const ALL_WALLS = 15;
function neighbor(i, d) {
const x = (i % GRID_N) + DX[d];
const y = Math.floor(i / GRID_N) + DY[d];
return x < 0 || y < 0 || x >= GRID_N || y >= GRID_N ? -1 : y * GRID_N + x;
}
function isOpen(walls, i, d) {
return (walls[i] & BIT[d]) === 0 && neighbor(i, d) >= 0;
}
// 벽 한 장 걷기 — 양쪽 칸의 비트를 함께 지운다 (한쪽만 지우면 길이 일방통행이 된다)
function knock(walls, i, d) {
const n = neighbor(i, d);
walls[i] &= ~BIT[d];
walls[n] &= ~BIT[(d + 2) % 4];
return n;
}
function openCount(walls, i) {
let c = 0;
for (let d = 0; d < 4; d += 1) {
if (isOpen(walls, i, d)) {
c += 1;
}
}
return c;
}
function cellX(i) { return BX + (i % GRID_N) * CS; }
function cellY(i) { return BY + Math.floor(i / GRID_N) * CS; }
function cellAt(sx, sy) {
const x = Math.floor((sx - BX) / CS);
const y = Math.floor((sy - BY) / CS);
return x < 0 || y < 0 || x >= GRID_N || y >= GRID_N ? -1 : y * GRID_N + x;
}
function fillCell(i, c, a) {
ctx.fillStyle = rgba(c, a);
ctx.fillRect(cellX(i), cellY(i), CS, CS);
}
// 벽 비트를 선분으로 — 칸마다 동·남 벽만 긋고 맨 윗줄·맨 왼줄만 북·서 벽을 더 긋는다 (같은 벽을 두 번 긋지 않는다)
function strokeWalls(walls, color, lw) {
ctx.beginPath();
for (let i = 0; i < CELL_N; i += 1) {
const x = cellX(i);
const y = cellY(i);
const w = walls[i];
if ((w & 2) !== 0) {
ctx.moveTo(x + CS, y);
ctx.lineTo(x + CS, y + CS);
}
if ((w & 4) !== 0) {
ctx.moveTo(x, y + CS);
ctx.lineTo(x + CS, y + CS);
}
if (i < GRID_N && (w & 1) !== 0) {
ctx.moveTo(x, y);
ctx.lineTo(x + CS, y);
}
if (i % GRID_N === 0 && (w & 8) !== 0) {
ctx.moveTo(x, y);
ctx.lineTo(x, y + CS);
}
}
ctx.strokeStyle = color;
ctx.lineWidth = lw;
ctx.lineCap = 'square';
ctx.stroke();
}
// 입구(왼쪽 위)·출구(오른쪽 아래) 표시 — 바깥 벽 밖에 작은 삼각형
function drawGates() {
ctx.fillStyle = rgba(MINT, 0.95);
ctx.beginPath();
ctx.moveTo(BX - 9, BY + 1);
ctx.lineTo(BX - 2, BY + CS / 2);
ctx.lineTo(BX - 9, BY + CS - 1);
ctx.closePath();
ctx.fill();
ctx.fillStyle = rgba(PINK, 0.95);
ctx.beginPath();
ctx.moveTo(BX + BOARD + 2, BY + BOARD - CS + 1);
ctx.lineTo(BX + BOARD + 9, BY + BOARD - CS / 2);
ctx.lineTo(BX + BOARD + 2, BY + BOARD - 1);
ctx.closePath();
ctx.fill();
}
// 왼쪽 칸의 수치 — 이름표 한 줄 + 값 한 줄
function panelRow(row, label, value) {
const y = 104 + row * 34;
ctx.textAlign = 'left';
ctx.textBaseline = 'alphabetic';
ctx.fillStyle = rgba(PAPER, 0.62);
ctx.font = '500 11px sans-serif';
ctx.fillText(label, 16, y);
ctx.fillStyle = rgba(PAPER, 0.96);
ctx.font = '700 15px sans-serif';
ctx.fillText(value, 16, y + 18);
}
function clearStage() {
ctx.fillStyle = rgba(BG, 1);
ctx.fillRect(0, 0, W, H);
}
// 깊이 우선 파기 한 번에 끝까지 — 스택 머리에서 안 판 이웃을 골라 벽을 걷고, 없으면 하나 뺀다
function carveDfsAll(seed, start) {
const walls = new Uint8Array(CELL_N).fill(ALL_WALLS);
const seen = new Uint8Array(CELL_N);
const stk = new Int32Array(CELL_N);
const rnd = makeRng(seed);
let sp = 0;
stk[sp] = start;
sp = 1;
seen[start] = 1;
const opts = [];
while (sp > 0) {
const cur = stk[sp - 1];
opts.length = 0;
for (let d = 0; d < 4; d += 1) {
const n = neighbor(cur, d);
if (n >= 0 && seen[n] === 0) {
opts.push(d);
}
}
if (opts.length === 0) {
sp -= 1;
continue;
}
const n = knock(walls, cur, opts[Math.floor(rnd() * opts.length)]);
seen[n] = 1;
stk[sp] = n;
sp += 1;
}
return walls;
}
// 너비 우선 거리 — 큐에서 꺼낸 칸의 열린 이웃에 거리+1 을 적는다. 닿지 않은 칸은 -1
function bfsDist(walls, src) {
const dist = new Int32Array(CELL_N).fill(-1);
const q = new Int32Array(CELL_N);
let head = 0;
let tail = 0;
dist[src] = 0;
q[tail] = src;
tail += 1;
while (head < tail) {
const c = q[head];
head += 1;
for (let d = 0; d < 4; d += 1) {
if (!isOpen(walls, c, d)) {
continue;
}
const n = neighbor(c, d);
if (dist[n] >= 0) {
continue;
}
dist[n] = dist[c] + 1;
q[tail] = n;
tail += 1;
}
}
return dist;
}
// Dead ends = 열린 쪽이 하나뿐인 칸
function isDeadEnd(walls, i) { return openCount(walls, i) === 1; }
// Dead ends 끝의 벽 하나를 걷어 옆길과 잇는다 — 옆 칸도 막다른 골목이면 그쪽을 먼저 골라 두 골목을 한 번에 없앤다
function spliceAt(walls, i, rnd) {
const shut = [];
const dead = [];
for (let d = 0; d < 4; d += 1) {
const n = neighbor(i, d);
if (n < 0 || (walls[i] & BIT[d]) === 0) {
continue;
}
shut.push(d);
if (isDeadEnd(walls, n)) {
dead.push(d);
}
}
const pool = dead.length > 0 ? dead : shut;
if (pool.length === 0) {
return -1;
}
const d = pool[Math.floor(rnd() * pool.length)];
knock(walls, i, d);
return d;
}
// 판 전체를 한 번 훑어 막다른 골목마다 keep 확률로 남기고 나머지는 잇는다 — 이은 수를 돌려준다
function braidAll(walls, keep, rnd) {
let joined = 0;
for (let i = 0; i < CELL_N; i += 1) {
if (!isDeadEnd(walls, i)) {
continue;
}
if (rnd() < keep) {
continue;
}
if (spliceAt(walls, i, rnd) >= 0) {
joined += 1;
}
}
return joined;
}
// Dead ends 가운데 그대로 Keep ratio — 0 이면 하나도 남기지 않고 전부 옆길과 잇는다
const BRAID_KEEP = 0;
// 칸 하나를 훑는 데 쓰는 시간 — 961칸이면 한 번 훑는 데 약 5.8초
const DEADEND_SCAN_MS = 6;
// 이은 벽 자리에 번지는 빛의 반지름(px)
const SPLICE_GLOW = 11;
const GLOW_MS = 900;
const SEED = 464;
const HOLD_MS = 1400;
const KEEP_STEPS = [BRAID_KEEP, 0.3, 0.6, 1];
const TXT_SCAN = 'Finding dead ends and splicing them';
const TXT_DONE = 'Scan done — spliced by the keep ratio';
const newBtn = root.querySelector('[data-role="new"]');
const keepBtn = root.querySelector('[data-role="keep"]');
let keep = BRAID_KEEP;
let pass = 0;
let base = carveDfsAll(SEED, ENTRY);
const walls = new Uint8Array(CELL_N);
const joinedMark = new Uint8Array(CELL_N);
const keptMark = new Uint8Array(CELL_N);
let rnd = makeRng(SEED);
let glows = [];
let si = 0;
let joined = 0;
let kept = 0;
let distNow = 0;
let stepAcc = 0;
let holdLeft = 0;
function deadCount() {
let c = 0;
for (let i = 0; i < CELL_N; i += 1) {
if (isDeadEnd(walls, i)) {
c += 1;
}
}
return c;
}
// 같은 미로를 처음 상태로 되돌려 다시 훑는다 — 비율을 바꿔도 미로는 그대로라 차이만 보인다
function rescan() {
walls.set(base);
joinedMark.fill(0);
keptMark.fill(0);
rnd = makeRng(SEED + pass * 7 + 1);
glows = [];
si = 0;
joined = 0;
kept = 0;
distNow = bfsDist(walls, ENTRY)[EXIT];
stepAcc = 0;
holdLeft = 0;
}
// 칸 하나 훑기 — 지금 막다른 골목이면 keep 확률로 남기고, 아니면 끝의 벽 하나를 걷어 옆길과 잇는다
function scanStep() {
if (si >= CELL_N) {
return;
}
const i = si;
si += 1;
if (!isDeadEnd(walls, i)) {
return;
}
if (rnd() < keep) {
kept += 1;
keptMark[i] = 1;
return;
}
const d = spliceAt(walls, i, rnd);
if (d < 0) {
return;
}
joined += 1;
joinedMark[i] = 1;
joinedMark[neighbor(i, d)] = 1;
glows.push({ cell: i, dir: d, age: 0 });
distNow = bfsDist(walls, ENTRY)[EXIT];
}
function done() { return si >= CELL_N; }
function report() { say(done() ? TXT_DONE : TXT_SCAN); }
function scan(n) {
for (let k = 0; k < n && !done(); k += 1) {
scanStep();
}
}
function step() {
for (const g of glows) {
g.age += FIXED_DT;
}
glows = glows.filter(function (g) { return g.age < GLOW_MS; });
if (done()) {
return;
}
stepAcc += FIXED_DT;
while (stepAcc >= DEADEND_SCAN_MS && !done()) {
stepAcc -= DEADEND_SCAN_MS;
scanStep();
}
report();
}
function settle() {
scan(CELL_N);
glows = [];
report();
}
function demoTick(t) {
if (!done() || t < 0) {
return;
}
holdLeft += FIXED_DT;
if (holdLeft >= HOLD_MS) {
newMaze();
}
}
const FLOOR = mix(PAPER, BG, 0.04);
const SCANNED = mix(PAPER, SKY, 0.22);
function draw() {
clearStage();
for (let i = 0; i < CELL_N; i += 1) {
let c = i < si ? SCANNED : FLOOR;
if (joinedMark[i] === 1) {
c = mix(c, MINT, 0.55);
}
fillCell(i, c, 1);
}
if (!done()) {
// 지금 훑는 줄 — 줄 전체를 옅게 덮고 지금 칸은 진하게
const row = Math.floor(si / GRID_N);
ctx.fillStyle = rgba(LILAC, 0.35);
ctx.fillRect(BX, BY + row * CS, BOARD, CS);
ctx.fillStyle = rgba(LILAC, 0.9);
ctx.fillRect(cellX(si), cellY(si), CS, CS);
}
strokeWalls(walls, rgba(INK, 1), 2);
for (let i = 0; i < CELL_N; i += 1) {
const dead = isDeadEnd(walls, i);
if (!dead) {
continue;
}
ctx.fillStyle = rgba(PINK, keptMark[i] === 1 ? 1 : 0.85);
ctx.beginPath();
ctx.arc(cellX(i) + CS / 2, cellY(i) + CS / 2, keptMark[i] === 1 ? 2.6 : 1.9, 0, Math.PI * 2);
ctx.fill();
}
for (const g of glows) {
const k = 1 - g.age / GLOW_MS;
const x = cellX(g.cell) + CS / 2 + DX[g.dir] * CS / 2;
const y = cellY(g.cell) + CS / 2 + DY[g.dir] * CS / 2;
const gr = ctx.createRadialGradient(x, y, 0, x, y, SPLICE_GLOW);
gr.addColorStop(0, rgba(PAPER, 0.95 * k));
gr.addColorStop(0.45, rgba(MINT, 0.7 * k));
gr.addColorStop(1, rgba(MINT, 0));
ctx.fillStyle = gr;
ctx.fillRect(x - SPLICE_GLOW, y - SPLICE_GLOW, SPLICE_GLOW * 2, SPLICE_GLOW * 2);
}
drawGates();
panelRow(0, 'Dead ends', String(deadCount()));
panelRow(1, 'Spliced', String(joined));
panelRow(2, 'Keep ratio', keep.toFixed(1));
panelRow(3, 'Entrance→exit', String(distNow));
}
function after() {
if (still) {
settle();
}
report();
draw();
}
function newMaze() {
pass += 1;
base = carveDfsAll(SEED + pass, ENTRY);
rescan();
after();
}
function setKeep(k) {
keep = k;
rescan();
after();
}
function stepKeep(dirn) {
const i = KEEP_STEPS.indexOf(keep);
setKeep(KEEP_STEPS[(i + dirn + KEEP_STEPS.length) % KEEP_STEPS.length]);
}
cv.addEventListener('pointerdown', function () { wake(); stepKeep(1); });
cv.addEventListener('keydown', function (ev) {
if (ev.key === 'ArrowUp') {
ev.preventDefault();
wake();
stepKeep(1);
}
else if (ev.key === 'ArrowDown') {
ev.preventDefault();
wake();
stepKeep(-1);
}
else if (ev.key === 'ArrowRight') {
ev.preventDefault();
wake();
scan(60);
after();
}
else if (ev.key === 'Home' || ev.key === 'Enter') {
ev.preventDefault();
wake();
newMaze();
}
});
if (newBtn) {
newBtn.addEventListener('click', function () { wake(); newMaze(); });
}
if (keepBtn) {
keepBtn.addEventListener('click', function () { wake(); stepKeep(1); });
}
rescan();
report();
let rafId = 0;
let lastTs = -1;
let acc = 0;
let clock = 0;
function frame(ts) {
if (lastTs < 0) {
lastTs = ts;
}
// 탭이 숨었다 돌아와도 한 번에 100ms 까지만 따라잡는다 — 순간이동 대신 이어서 움직인다
acc += Math.min(ts - lastTs, 100);
lastTs = ts;
let n = 0;
while (acc >= FIXED_DT && n < 6) {
clock += FIXED_DT;
if (demo) {
demoTick(clock);
}
step();
acc -= FIXED_DT;
n += 1;
}
draw();
rafId = window.requestAnimationFrame(frame);
}
if (still) {
settle();
draw();
}
else {
rafId = window.requestAnimationFrame(frame);
}
return function () {
window.cancelAnimationFrame(rafId);
window.removeEventListener('resize', onResize);
};
})();// MzBraidOpenLoopDeadend - vanilla 판(04-mz-braid-open-loop-deadend) 의 React 포트. 같은 계산을 useEffect 안에서 돌린다.
import { useEffect, useRef } from "react";
import styles from "./MzBraidOpenLoopDeadend.module.scss";
const cx = (s: string): string => s.split(" ").map((n) => styles[n] ?? n).join(" ");
export default function MzBraidOpenLoopDeadend() {
const rootRef = useRef<HTMLDivElement | null>(null);
useEffect(() => {
const rootEl = rootRef.current;
if (!rootEl) return;
const root: HTMLElement = rootEl;
type RGB = [number, number, number];
const W = 480;
const H = 300;
const FIXED_DT = 16;
// 파스텔 팔레트 — 어두운 무대 위에 밝은 바닥을 얹어 명도 차로 길이 읽힌다
const BG: RGB = [29, 26, 44];
const ROCK: RGB = [44, 39, 64];
const PAPER: RGB = [255, 248, 234];
const INK: RGB = [58, 48, 76];
const MINT: RGB = [126, 226, 192];
const SKY: RGB = [124, 196, 255];
const LILAC: RGB = [190, 164, 255];
const PINK: RGB = [255, 160, 190];
const PEACH: RGB = [255, 208, 168];
function clamp(v: number, lo: number, hi: number): number { return v < lo ? lo : (v > hi ? hi : v); }
function lerp(a: number, b: number, k: number): number { return a + (b - a) * k; }
function smooth(x: number): number { const c = clamp(x, 0, 1); return c * c * (3 - 2 * c); }
function rgba(c: RGB, a: number): string {
return 'rgba(' + Math.round(c[0]) + ',' + Math.round(c[1]) + ',' + Math.round(c[2]) + ',' + clamp(a, 0, 1).toFixed(3) + ')';
}
function mix(a: RGB, b: RGB, k: number): RGB { return [lerp(a[0], b[0], k), lerp(a[1], b[1], k), lerp(a[2], b[2], k)]; }
const canvasEl = root.querySelector('[data-role="canvas"]') as HTMLCanvasElement | null;
const statusEl = root.querySelector('[data-role="status"]') as HTMLElement | null;
const ctxRaw = canvasEl ? canvasEl.getContext('2d') : null;
if (!canvasEl || !ctxRaw || !statusEl) { return; }
const cv: HTMLCanvasElement = canvasEl;
const ctx: CanvasRenderingContext2D = ctxRaw;
const status: HTMLElement = statusEl;
const reduceQuery = window.matchMedia('(prefers-reduced-motion: reduce)');
const still = reduceQuery.matches;
// 자동 시연 중인가 — 사람이 처음 만지는 순간 시연을 멈추고 상태 줄을 읽어 주기 시작한다
let demo = root.classList.contains('is-demo');
function wake(): void {
if (!demo) { return; }
demo = false;
root.classList.remove('is-demo');
status.setAttribute('aria-live', 'polite');
}
function say(text: string): void {
if (status.textContent !== text) { status.textContent = text; }
}
function fitCanvas(): void {
// 배율은 2 에서 자른다 — 배율 3 기기에서 화소가 2.25배로 늘어 프레임마다 일이 그만큼 커지지 않게
const dpr = Math.min(window.devicePixelRatio || 1, 2);
cv.width = Math.round(W * dpr);
cv.height = Math.round(H * dpr);
ctx.setTransform(dpr, 0, 0, dpr, 0, 0);
}
function onResize(): void {
fitCanvas();
draw();
}
fitCanvas();
window.addEventListener('resize', onResize);
// 화면 좌표(CSS px) → 장면 좌표(480x300). 리사이즈 뒤에도 늘 현재 크기로 다시 잰다
function toScene(ev: PointerEvent): [number, number] {
const r = cv.getBoundingClientRect();
return [((ev.clientX - r.left) / r.width) * W, ((ev.clientY - r.top) / r.height) * H];
}
// 시드 고정 난수 — 같은 시드면 같은 미로가 다시 나온다 (32비트 정수 섞기)
function makeRng(seed: number): () => number {
let s = seed >>> 0;
return function (): number {
s = (s + 0x6d2b79f5) >>> 0;
let t = s;
t = Math.imul(t ^ (t >>> 15), t | 1);
t ^= t + Math.imul(t ^ (t >>> 7), t | 61);
return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
};
}
// 격자 — 31×31 칸, 칸마다 벽 네 장을 비트 하나씩으로 든다
const GRID_N = 31;
const CELL_N = GRID_N * GRID_N;
const CS = 9;
const BOARD = GRID_N * CS;
let BX = W - 12 - BOARD;
const BY = (H - BOARD) / 2;
const ENTRY = 0;
const EXIT = CELL_N - 1;
// 방향 0 북 · 1 동 · 2 남 · 3 서 — 시계 방향 순서라 +1 이 오른쪽으로 돌기, +3 이 왼쪽으로 돌기
const DX = [0, 1, 0, -1];
const DY = [-1, 0, 1, 0];
const BIT = [1, 2, 4, 8];
const ALL_WALLS = 15;
function neighbor(i: number, d: number): number {
const x = (i % GRID_N) + DX[d];
const y = Math.floor(i / GRID_N) + DY[d];
return x < 0 || y < 0 || x >= GRID_N || y >= GRID_N ? -1 : y * GRID_N + x;
}
function isOpen(walls: Uint8Array, i: number, d: number): boolean {
return (walls[i] & BIT[d]) === 0 && neighbor(i, d) >= 0;
}
// 벽 한 장 걷기 — 양쪽 칸의 비트를 함께 지운다 (한쪽만 지우면 길이 일방통행이 된다)
function knock(walls: Uint8Array, i: number, d: number): number {
const n = neighbor(i, d);
walls[i] &= ~BIT[d];
walls[n] &= ~BIT[(d + 2) % 4];
return n;
}
function openCount(walls: Uint8Array, i: number): number {
let c = 0;
for (let d = 0; d < 4; d += 1) { if (isOpen(walls, i, d)) { c += 1; } }
return c;
}
function cellX(i: number): number { return BX + (i % GRID_N) * CS; }
function cellY(i: number): number { return BY + Math.floor(i / GRID_N) * CS; }
function cellAt(sx: number, sy: number): number {
const x = Math.floor((sx - BX) / CS);
const y = Math.floor((sy - BY) / CS);
return x < 0 || y < 0 || x >= GRID_N || y >= GRID_N ? -1 : y * GRID_N + x;
}
function fillCell(i: number, c: RGB, a: number): void {
ctx.fillStyle = rgba(c, a);
ctx.fillRect(cellX(i), cellY(i), CS, CS);
}
// 벽 비트를 선분으로 — 칸마다 동·남 벽만 긋고 맨 윗줄·맨 왼줄만 북·서 벽을 더 긋는다 (같은 벽을 두 번 긋지 않는다)
function strokeWalls(walls: Uint8Array, color: string, lw: number): void {
ctx.beginPath();
for (let i = 0; i < CELL_N; i += 1) {
const x = cellX(i);
const y = cellY(i);
const w = walls[i];
if ((w & 2) !== 0) { ctx.moveTo(x + CS, y); ctx.lineTo(x + CS, y + CS); }
if ((w & 4) !== 0) { ctx.moveTo(x, y + CS); ctx.lineTo(x + CS, y + CS); }
if (i < GRID_N && (w & 1) !== 0) { ctx.moveTo(x, y); ctx.lineTo(x + CS, y); }
if (i % GRID_N === 0 && (w & 8) !== 0) { ctx.moveTo(x, y); ctx.lineTo(x, y + CS); }
}
ctx.strokeStyle = color;
ctx.lineWidth = lw;
ctx.lineCap = 'square';
ctx.stroke();
}
// 입구(왼쪽 위)·출구(오른쪽 아래) 표시 — 바깥 벽 밖에 작은 삼각형
function drawGates(): void {
ctx.fillStyle = rgba(MINT, 0.95);
ctx.beginPath();
ctx.moveTo(BX - 9, BY + 1);
ctx.lineTo(BX - 2, BY + CS / 2);
ctx.lineTo(BX - 9, BY + CS - 1);
ctx.closePath();
ctx.fill();
ctx.fillStyle = rgba(PINK, 0.95);
ctx.beginPath();
ctx.moveTo(BX + BOARD + 2, BY + BOARD - CS + 1);
ctx.lineTo(BX + BOARD + 9, BY + BOARD - CS / 2);
ctx.lineTo(BX + BOARD + 2, BY + BOARD - 1);
ctx.closePath();
ctx.fill();
}
// 왼쪽 칸의 수치 — 이름표 한 줄 + 값 한 줄
function panelRow(row: number, label: string, value: string): void {
const y = 104 + row * 34;
ctx.textAlign = 'left';
ctx.textBaseline = 'alphabetic';
ctx.fillStyle = rgba(PAPER, 0.62);
ctx.font = '500 11px sans-serif';
ctx.fillText(label, 16, y);
ctx.fillStyle = rgba(PAPER, 0.96);
ctx.font = '700 15px sans-serif';
ctx.fillText(value, 16, y + 18);
}
function clearStage(): void {
ctx.fillStyle = rgba(BG, 1);
ctx.fillRect(0, 0, W, H);
}
// 깊이 우선 파기 한 번에 끝까지 — 스택 머리에서 안 판 이웃을 골라 벽을 걷고, 없으면 하나 뺀다
function carveDfsAll(seed: number, start: number): Uint8Array {
const walls = new Uint8Array(CELL_N).fill(ALL_WALLS);
const seen = new Uint8Array(CELL_N);
const stk = new Int32Array(CELL_N);
const rnd = makeRng(seed);
let sp = 0;
stk[sp] = start;
sp = 1;
seen[start] = 1;
const opts: number[] = [];
while (sp > 0) {
const cur = stk[sp - 1];
opts.length = 0;
for (let d = 0; d < 4; d += 1) {
const n = neighbor(cur, d);
if (n >= 0 && seen[n] === 0) { opts.push(d); }
}
if (opts.length === 0) { sp -= 1; continue; }
const n = knock(walls, cur, opts[Math.floor(rnd() * opts.length)]);
seen[n] = 1;
stk[sp] = n;
sp += 1;
}
return walls;
}
// 너비 우선 거리 — 큐에서 꺼낸 칸의 열린 이웃에 거리+1 을 적는다. 닿지 않은 칸은 -1
function bfsDist(walls: Uint8Array, src: number): Int32Array {
const dist = new Int32Array(CELL_N).fill(-1);
const q = new Int32Array(CELL_N);
let head = 0;
let tail = 0;
dist[src] = 0;
q[tail] = src;
tail += 1;
while (head < tail) {
const c = q[head];
head += 1;
for (let d = 0; d < 4; d += 1) {
if (!isOpen(walls, c, d)) { continue; }
const n = neighbor(c, d);
if (dist[n] >= 0) { continue; }
dist[n] = dist[c] + 1;
q[tail] = n;
tail += 1;
}
}
return dist;
}
// 막다른 골목 = 열린 쪽이 하나뿐인 칸
function isDeadEnd(walls: Uint8Array, i: number): boolean { return openCount(walls, i) === 1; }
// 막다른 골목 끝의 벽 하나를 걷어 옆길과 잇는다 — 옆 칸도 막다른 골목이면 그쪽을 먼저 골라 두 골목을 한 번에 없앤다
function spliceAt(walls: Uint8Array, i: number, rnd: () => number): number {
const shut: number[] = [];
const dead: number[] = [];
for (let d = 0; d < 4; d += 1) {
const n = neighbor(i, d);
if (n < 0 || (walls[i] & BIT[d]) === 0) { continue; }
shut.push(d);
if (isDeadEnd(walls, n)) { dead.push(d); }
}
const pool = dead.length > 0 ? dead : shut;
if (pool.length === 0) { return -1; }
const d = pool[Math.floor(rnd() * pool.length)];
knock(walls, i, d);
return d;
}
// 판 전체를 한 번 훑어 막다른 골목마다 keep 확률로 남기고 나머지는 잇는다 — 이은 수를 돌려준다
function braidAll(walls: Uint8Array, keep: number, rnd: () => number): number {
let joined = 0;
for (let i = 0; i < CELL_N; i += 1) {
if (!isDeadEnd(walls, i)) { continue; }
if (rnd() < keep) { continue; }
if (spliceAt(walls, i, rnd) >= 0) { joined += 1; }
}
return joined;
}
// 막다른 골목 가운데 그대로 남길 비율 — 0 이면 하나도 남기지 않고 전부 옆길과 잇는다
const BRAID_KEEP = 0;
// 칸 하나를 훑는 데 쓰는 시간 — 961칸이면 한 번 훑는 데 약 5.8초
const DEADEND_SCAN_MS = 6;
// 이은 벽 자리에 번지는 빛의 반지름(px)
const SPLICE_GLOW = 11;
const GLOW_MS = 900;
const SEED = 464;
const HOLD_MS = 1400;
const KEEP_STEPS = [BRAID_KEEP, 0.3, 0.6, 1];
const TXT_SCAN = '막다른 골목을 찾아 잇는 중';
const TXT_DONE = '훑기 끝 — 남길 비율대로 이음';
const newBtn = root.querySelector('[data-role="new"]') as HTMLButtonElement | null;
const keepBtn = root.querySelector('[data-role="keep"]') as HTMLButtonElement | null;
type Glow = { cell: number; dir: number; age: number };
let keep = BRAID_KEEP;
let pass = 0;
let base = carveDfsAll(SEED, ENTRY);
const walls = new Uint8Array(CELL_N);
const joinedMark = new Uint8Array(CELL_N);
const keptMark = new Uint8Array(CELL_N);
let rnd = makeRng(SEED);
let glows: Glow[] = [];
let si = 0;
let joined = 0;
let kept = 0;
let distNow = 0;
let stepAcc = 0;
let holdLeft = 0;
function deadCount(): number {
let c = 0;
for (let i = 0; i < CELL_N; i += 1) { if (isDeadEnd(walls, i)) { c += 1; } }
return c;
}
// 같은 미로를 처음 상태로 되돌려 다시 훑는다 — 비율을 바꿔도 미로는 그대로라 차이만 보인다
function rescan(): void {
walls.set(base);
joinedMark.fill(0);
keptMark.fill(0);
rnd = makeRng(SEED + pass * 7 + 1);
glows = [];
si = 0;
joined = 0;
kept = 0;
distNow = bfsDist(walls, ENTRY)[EXIT];
stepAcc = 0;
holdLeft = 0;
}
// 칸 하나 훑기 — 지금 막다른 골목이면 keep 확률로 남기고, 아니면 끝의 벽 하나를 걷어 옆길과 잇는다
function scanStep(): void {
if (si >= CELL_N) { return; }
const i = si;
si += 1;
if (!isDeadEnd(walls, i)) { return; }
if (rnd() < keep) { kept += 1; keptMark[i] = 1; return; }
const d = spliceAt(walls, i, rnd);
if (d < 0) { return; }
joined += 1;
joinedMark[i] = 1;
joinedMark[neighbor(i, d)] = 1;
glows.push({ cell: i, dir: d, age: 0 });
distNow = bfsDist(walls, ENTRY)[EXIT];
}
function done(): boolean { return si >= CELL_N; }
function report(): void { say(done() ? TXT_DONE : TXT_SCAN); }
function scan(n: number): void {
for (let k = 0; k < n && !done(); k += 1) { scanStep(); }
}
function step(): void {
for (const g of glows) { g.age += FIXED_DT; }
glows = glows.filter(function (g: Glow): boolean { return g.age < GLOW_MS; });
if (done()) { return; }
stepAcc += FIXED_DT;
while (stepAcc >= DEADEND_SCAN_MS && !done()) {
stepAcc -= DEADEND_SCAN_MS;
scanStep();
}
report();
}
function settle(): void {
scan(CELL_N);
glows = [];
report();
}
function demoTick(t: number): void {
if (!done() || t < 0) { return; }
holdLeft += FIXED_DT;
if (holdLeft >= HOLD_MS) { newMaze(); }
}
const FLOOR = mix(PAPER, BG, 0.04);
const SCANNED = mix(PAPER, SKY, 0.22);
function draw(): void {
clearStage();
for (let i = 0; i < CELL_N; i += 1) {
let c = i < si ? SCANNED : FLOOR;
if (joinedMark[i] === 1) { c = mix(c, MINT, 0.55); }
fillCell(i, c, 1);
}
if (!done()) {
// 지금 훑는 줄 — 줄 전체를 옅게 덮고 지금 칸은 진하게
const row = Math.floor(si / GRID_N);
ctx.fillStyle = rgba(LILAC, 0.35);
ctx.fillRect(BX, BY + row * CS, BOARD, CS);
ctx.fillStyle = rgba(LILAC, 0.9);
ctx.fillRect(cellX(si), cellY(si), CS, CS);
}
strokeWalls(walls, rgba(INK, 1), 2);
for (let i = 0; i < CELL_N; i += 1) {
const dead = isDeadEnd(walls, i);
if (!dead) { continue; }
ctx.fillStyle = rgba(PINK, keptMark[i] === 1 ? 1 : 0.85);
ctx.beginPath();
ctx.arc(cellX(i) + CS / 2, cellY(i) + CS / 2, keptMark[i] === 1 ? 2.6 : 1.9, 0, Math.PI * 2);
ctx.fill();
}
for (const g of glows) {
const k = 1 - g.age / GLOW_MS;
const x = cellX(g.cell) + CS / 2 + DX[g.dir] * CS / 2;
const y = cellY(g.cell) + CS / 2 + DY[g.dir] * CS / 2;
const gr = ctx.createRadialGradient(x, y, 0, x, y, SPLICE_GLOW);
gr.addColorStop(0, rgba(PAPER, 0.95 * k));
gr.addColorStop(0.45, rgba(MINT, 0.7 * k));
gr.addColorStop(1, rgba(MINT, 0));
ctx.fillStyle = gr;
ctx.fillRect(x - SPLICE_GLOW, y - SPLICE_GLOW, SPLICE_GLOW * 2, SPLICE_GLOW * 2);
}
drawGates();
panelRow(0, '막다른 골목', String(deadCount()));
panelRow(1, '이은 골목', String(joined));
panelRow(2, '남길 비율', keep.toFixed(1));
panelRow(3, '입구→출구 거리', String(distNow));
}
function after(): void {
if (still) { settle(); }
report();
draw();
}
function newMaze(): void {
pass += 1;
base = carveDfsAll(SEED + pass, ENTRY);
rescan();
after();
}
function setKeep(k: number): void {
keep = k;
rescan();
after();
}
function stepKeep(dirn: number): void {
const i = KEEP_STEPS.indexOf(keep);
setKeep(KEEP_STEPS[(i + dirn + KEEP_STEPS.length) % KEEP_STEPS.length]);
}
cv.addEventListener('pointerdown', function (): void { wake(); stepKeep(1); });
cv.addEventListener('keydown', function (ev: KeyboardEvent): void {
if (ev.key === 'ArrowUp') { ev.preventDefault(); wake(); stepKeep(1); }
else if (ev.key === 'ArrowDown') { ev.preventDefault(); wake(); stepKeep(-1); }
else if (ev.key === 'ArrowRight') { ev.preventDefault(); wake(); scan(60); after(); }
else if (ev.key === 'Home' || ev.key === 'Enter') { ev.preventDefault(); wake(); newMaze(); }
});
if (newBtn) { newBtn.addEventListener('click', function (): void { wake(); newMaze(); }); }
if (keepBtn) { keepBtn.addEventListener('click', function (): void { wake(); stepKeep(1); }); }
rescan();
report();
let rafId = 0;
let lastTs = -1;
let acc = 0;
let clock = 0;
function frame(ts: number): void {
if (lastTs < 0) { lastTs = ts; }
// 탭이 숨었다 돌아와도 한 번에 100ms 까지만 따라잡는다 — 순간이동 대신 이어서 움직인다
acc += Math.min(ts - lastTs, 100);
lastTs = ts;
let n = 0;
while (acc >= FIXED_DT && n < 6) {
clock += FIXED_DT;
if (demo) { demoTick(clock); }
step();
acc -= FIXED_DT;
n += 1;
}
draw();
rafId = window.requestAnimationFrame(frame);
}
if (still) {
settle();
draw();
} else {
rafId = window.requestAnimationFrame(frame);
}
return function (): void {
window.cancelAnimationFrame(rafId);
window.removeEventListener('resize', onResize);
};
}, []);
return (
<div className={cx("hs") + " is-demo"} ref={rootRef}>
<canvas className={cx("hs__canvas")} data-role="canvas" width={480} height={300} tabIndex={0} aria-label="완성된 미로를 한 칸씩 훑어 막다른 골목 끝의 벽을 걷어 옆길과 잇는 판. 누르면 남길 비율이 바뀐다"></canvas>
<p className={cx("hs__status")} data-role="status" aria-live="off">막다른 골목을 찾아 잇는 중</p>
<div className={cx("hs__tools")}>
<button className={cx("hs__btn")} data-role="new" type="button">새 미로</button>
<button className={cx("hs__btn")} data-role="keep" type="button">남길 비율 바꾸기</button>
</div>
</div>
);
}04 A Maze That Reopens Dead Ends to Leave Multiple Ways Through — Measured area 19.073% · moving frames 23/23Original by GODRICH · SCSS and React ship in the zip · Maze Generator: 9 Carve-and-Solve Scenes
The post this demo lives in
Maze Generator: 9 Carve-and-Solve ScenesIn this maze generator set, mazes are carved, not drawn — 02 reads carve order from a random frontier's ripple bands, 06 See all demos in this post
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