06QR Code That Settles as Its Jitter Amplitude Shrinks While Generating

<main class="stage">
<div class="gns is-demo" id="gnsRoot">
  <div class="gns__badge" id="gnsBadge">Generating code</div>
  <button class="gns__ctrl" id="gnsCtrl" type="button">Pause</button>
  <div class="gns__canvas-wrap">
    <canvas class="gns__canvas" id="gnsCanvas" width="240" height="200"></canvas>
  </div>
</div>
</main>

@use "../../../../site/static/demo-tokens" as *;

// 핵심: 모듈별 위상·방향으로 흔드는 노이즈 진폭이 시간에 따라 지수 감쇠해
// 0으로 수렴한다 — 흔들리던 픽셀이 점점 제자리로 가라앉는다.

@include stage($stage-ink);

.gns {
  position: relative;
  width: min(100%, 280px);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: $sp-3;
}

.gns__badge {
  padding: $sp-1 $sp-3;
  border-radius: $r-pill;
  background: rgba(255, 247, 230, .08);
  color: $subject-cream;
  font-weight: 700;
  font-size: 11px;
  font-variant-numeric: tabular-nums;
}

.gns__ctrl {
  position: absolute;
  top: 0;
  right: 0;
  border: 0;
  border-radius: $r-xs;
  padding: $sp-1 $sp-2;
  background: rgba(255, 247, 230, .12);
  color: $subject-cream;
  font-weight: 600;
  font-size: 10px;
  line-height: 1.4;
  cursor: pointer;
}
.gns__ctrl:focus-visible { outline: 2px solid $subject-blue-light; outline-offset: 2px; }

.gns__canvas-wrap {
  width: 100%;
  aspect-ratio: 7 / 5;
  border-radius: $r-card;
  background: rgba(255, 255, 255, .04);
  display: grid;
  place-items: center;
  overflow: hidden;
}

.gns__canvas {
  width: 100%;
  height: 100%;
  display: block;
}

@media (max-width: 340px) {
  .gns { gap: $sp-1; }
  .gns__badge { padding: $sp-1 $sp-2; font-size: 10px; }
  .gns__canvas-wrap { max-width: 150px; aspect-ratio: 3 / 2; margin: 0 auto; }
}

@media (prefers-reduced-motion: reduce) {
  .gns__canvas-wrap { background: rgba(255, 255, 255, .04); }
}

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);
}

.gns {
  position: relative;
  width: min(100%, 280px);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.gns__badge {
  padding: 4px 12px;
  border-radius: 999px;
  background: rgba(255, 247, 230, 0.08);
  color: #fff7e6;
  font-weight: 700;
  font-size: 11px;
  font-variant-numeric: tabular-nums;
}

.gns__ctrl {
  position: absolute;
  top: 0;
  right: 0;
  border: 0;
  border-radius: 4px;
  padding: 4px 8px;
  background: rgba(255, 247, 230, 0.12);
  color: #fff7e6;
  font-weight: 600;
  font-size: 10px;
  line-height: 1.4;
  cursor: pointer;
}

.gns__ctrl:focus-visible {
  outline: 2px solid #5b8cf8;
  outline-offset: 2px;
}

.gns__canvas-wrap {
  width: 100%;
  aspect-ratio: 7/5;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.04);
  display: grid;
  place-items: center;
  overflow: hidden;
}

.gns__canvas {
  width: 100%;
  height: 100%;
  display: block;
}

@media (max-width: 340px) {
  .gns {
    gap: 4px;
  }
  .gns__badge {
    padding: 4px 8px;
    font-size: 10px;
  }
  .gns__canvas-wrap {
    max-width: 150px;
    aspect-ratio: 3/2;
    margin: 0 auto;
  }
}
@media (prefers-reduced-motion: reduce) {
  .gns__canvas-wrap {
    background: rgba(255, 255, 255, 0.04);
  }
}

(function () {
  // QR_NOISE_SETTLE_AMPLITUDE_PX — 변형 1: 6 → 2 로 늘리면 초기 흔들림 폭이 더 커진다(전값이 초기값).
  var QR_NOISE_SETTLE_AMPLITUDE_PX = 6;
  var LOOP_MS = 2000;
  var SETTLE_MS = 1500;
  var SIZE = 13;

  var canvas = document.getElementById('gnsCanvas');
  var ctx = canvas.getContext('2d');
  var badge = document.getElementById('gnsBadge');
  var ctrl = document.getElementById('gnsCtrl');
  var root = document.getElementById('gnsRoot');

  function seedRand(seed) {
    var s = seed >>> 0;
    return function () { s = (s * 1664525 + 1013904223) >>> 0; return s / 4294967296; };
  }
  var rand = seedRand(407060);
  var modules = [];
  for (var y = 0; y < SIZE; y += 1) {
    for (var x = 0; x < SIZE; x += 1) {
      if (rand() < 0.45) {
        modules.push({
          x: x, y: y,
          phase: rand() * Math.PI * 2,
          freq: 6 + rand() * 4,
          dir: rand() * Math.PI * 2
        });
      }
    }
  }

  function draw(elapsed) {
    var cw = canvas.width, ch = canvas.height;
    ctx.clearRect(0, 0, cw, ch);
    var box = Math.min(cw, ch) - 40;
    var cell = box / SIZE;
    var ox = (cw - box) / 2, oy = (ch - box) / 2;

    // 계산 한 겹: 진폭이 시간에 따라 지수 감쇠 — 초기 QR_NOISE_SETTLE_AMPLITUDE_PX 에서
    // SETTLE_MS 동안 0으로 잦아들며, 모듈마다 다른 위상·방향으로 흔들려 자리를 잡는다.
    var settleP = Math.min(1, elapsed / SETTLE_MS);
    var amp = QR_NOISE_SETTLE_AMPLITUDE_PX * Math.exp(-4 * settleP);

    ctx.fillStyle = 'rgb(255,247,230)';
    modules.forEach(function (m) {
      var wobble = Math.sin(elapsed / 1000 * m.freq + m.phase) * amp;
      var jx = Math.cos(m.dir) * wobble;
      var jy = Math.sin(m.dir) * wobble;
      var s = cell * 0.68;
      var cx = ox + m.x * cell + cell / 2 + jx;
      var cy = oy + m.y * cell + cell / 2 + jy;
      ctx.globalAlpha = 0.55 + 0.45 * settleP;
      ctx.fillRect(cx - s / 2, cy - s / 2, s, s);
    });
    ctx.globalAlpha = 1;

    badge.textContent = settleP >= 1 ? 'Code generated' : 'Generating code ' + Math.round(settleP * 100) + '%';
  }

  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  var playing = true;
  var elapsed = reduce ? SETTLE_MS : 0;
  if (reduce) {
    playing = false;
    root.classList.remove('is-demo');
  }

  var lastTs = null;
  function tick(ts) {
    if (lastTs === null) lastTs = ts;
    var dt = ts - lastTs;
    lastTs = ts;
    if (playing) {
      elapsed += dt;
      if (elapsed >= LOOP_MS) elapsed -= LOOP_MS;
    }
    draw(elapsed);
    requestAnimationFrame(tick);
  }
  draw(elapsed);
  requestAnimationFrame(tick);

  ctrl.addEventListener('click', function () {
    playing = !playing;
    ctrl.textContent = playing ? 'Pause' : 'Play';
  });
  ctrl.addEventListener('keydown', function (e) {
    if ((e.key === 'r' || e.key === 'R') && !reduce) {
      elapsed = 0;
      playing = true;
      ctrl.textContent = 'Pause';
    }
  });
})();

import { useEffect, useRef, useState } from "react";
import styles from "./GenerateNoiseSettle.module.scss";

export default function GenerateNoiseSettle() {
  const rootRef = useRef<HTMLDivElement>(null);
  const canvasRef = useRef<HTMLCanvasElement>(null);
  const ctrlRef = useRef<HTMLButtonElement>(null);
  const [badge, setBadge] = useState("코드 생성 중");
  const [ctrlLabel, setCtrlLabel] = useState("일시정지");

  useEffect(() => {
    const root = rootRef.current;
    const canvas = canvasRef.current;
    const ctrl = ctrlRef.current;
    if (!root || !canvas || !ctrl) return;
    const ctx = canvas.getContext("2d");
    if (!ctx) return;

    // QR_NOISE_SETTLE_AMPLITUDE_PX — 변형 1: 6 → 2 로 늘리면 초기 흔들림 폭이 더 커진다(전값이 초기값).
    const QR_NOISE_SETTLE_AMPLITUDE_PX = 6;
    const LOOP_MS = 2000;
    const SETTLE_MS = 1500;
    const SIZE = 13;

    function seedRand(seed: number) {
      let s = seed >>> 0;
      return function () {
        s = (s * 1664525 + 1013904223) >>> 0;
        return s / 4294967296;
      };
    }
    const rand = seedRand(407060);
    const modules: { x: number; y: number; phase: number; freq: number; dir: number }[] = [];
    for (let y = 0; y < SIZE; y += 1) {
      for (let x = 0; x < SIZE; x += 1) {
        if (rand() < 0.45) {
          modules.push({
            x, y,
            phase: rand() * Math.PI * 2,
            freq: 6 + rand() * 4,
            dir: rand() * Math.PI * 2,
          });
        }
      }
    }

    function draw(elapsed: number) {
      const cw = canvas!.width, ch = canvas!.height;
      ctx!.clearRect(0, 0, cw, ch);
      const box = Math.min(cw, ch) - 40;
      const cell = box / SIZE;
      const ox = (cw - box) / 2, oy = (ch - box) / 2;

      // 계산 한 겹: 진폭이 시간에 따라 지수 감쇠 — 초기 QR_NOISE_SETTLE_AMPLITUDE_PX 에서
      // SETTLE_MS 동안 0으로 잦아들며, 모듈마다 다른 위상·방향으로 흔들려 자리를 잡는다.
      const settleP = Math.min(1, elapsed / SETTLE_MS);
      const amp = QR_NOISE_SETTLE_AMPLITUDE_PX * Math.exp(-4 * settleP);

      ctx!.fillStyle = "rgb(255,247,230)";
      modules.forEach((m) => {
        const wobble = Math.sin((elapsed / 1000) * m.freq + m.phase) * amp;
        const jx = Math.cos(m.dir) * wobble;
        const jy = Math.sin(m.dir) * wobble;
        const s = cell * 0.68;
        const cx = ox + m.x * cell + cell / 2 + jx;
        const cy = oy + m.y * cell + cell / 2 + jy;
        ctx!.globalAlpha = 0.55 + 0.45 * settleP;
        ctx!.fillRect(cx - s / 2, cy - s / 2, s, s);
      });
      ctx!.globalAlpha = 1;

      setBadge(settleP >= 1 ? "코드 생성 완료" : "코드 생성 중 " + Math.round(settleP * 100) + "%");
    }

    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
    let playing = true;
    let elapsed = reduce ? SETTLE_MS : 0;
    if (reduce) {
      playing = false;
      root.classList.remove("is-demo");
    }

    let lastTs: number | null = null;
    let raf = 0;
    function tick(ts: number) {
      if (lastTs === null) lastTs = ts;
      const dt = ts - lastTs;
      lastTs = ts;
      if (playing) {
        elapsed += dt;
        if (elapsed >= LOOP_MS) elapsed -= LOOP_MS;
      }
      draw(elapsed);
      raf = requestAnimationFrame(tick);
    }
    draw(elapsed);
    raf = requestAnimationFrame(tick);

    function onClick() {
      playing = !playing;
      setCtrlLabel(playing ? "일시정지" : "재생");
    }
    function onKeydown(e: KeyboardEvent) {
      if ((e.key === "r" || e.key === "R") && !reduce) {
        elapsed = 0;
        playing = true;
        setCtrlLabel("일시정지");
      }
    }
    ctrl.addEventListener("click", onClick);
    ctrl.addEventListener("keydown", onKeydown);

    return () => {
      cancelAnimationFrame(raf);
      ctrl.removeEventListener("click", onClick);
      ctrl.removeEventListener("keydown", onKeydown);
    };
  }, []);

  return (
    <main className={styles.stage}>
      <div className={`${styles.gns} is-demo`} ref={rootRef}>
        <div className={styles.gns__badge}>{badge}</div>
        <button className={styles.gns__ctrl} type="button" ref={ctrlRef}>{ctrlLabel}</button>
        <div className={styles["gns__canvas-wrap"]}>
          <canvas className={styles.gns__canvas} ref={canvasRef} width={240} height={200} />
        </div>
      </div>
    </main>
  );
}