07360-degree view you drag around

<main class="stage">
  <div class="sp is-demo" id="sp">
    <div class="sp__win" id="sp-win" tabindex="0" role="img" aria-label="Mug in 360 degrees. Turn it with the arrow keys">
      <div class="sp__track" id="sp-track">
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
        <div class="sp__f"><i class="sp__handle"></i><i class="sp__body"></i><i class="sp__logo"></i></div>
      </div>
    </div>
  </div>
</main>

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

$duration: $dur-base;
$easing: $ease-out;
$color: $subject-ink;

@include stage($stage-yellow);

.sp { position: relative; }

.sp__win {
  box-sizing: border-box;
  width: 288px;
  height: 168px;
  overflow: hidden;
  border-radius: $r-card;
  background: linear-gradient($stage-ink, #2f2838);
  box-shadow: $shadow-raised;
  cursor: grab;
  touch-action: none;
}
.sp__win:focus-visible { outline: 3px solid $subject-ink; outline-offset: 2px; }

// 열두 칸이 한 줄로 붙어 있고 창은 한 칸만 보여 준다. gap 은 0 — 있으면 한 바퀴마다 어긋난다
.sp__track {
  display: flex;
  width: 1200%;
  height: 100%;
  transform: translateX(0);
}
.sp__f {
  position: relative;
  flex: 0 0 8.3333%;
  height: 100%;
  display: grid;
  place-items: center;
}
.sp__f > i {
  position: absolute;
  left: 50%;
  top: 50%;
  display: block;
}

// 가짜 사진 — 파일 없이 그린 머그컵. 손잡이와 로고가 각도마다 자리를 바꾼다
.sp__body {
  width: 92px;
  height: 108px;
  margin-left: -46px;
  margin-top: -54px;
  border-radius: $r-control $r-control $r-card $r-card;
  background: linear-gradient(90deg, #a96953 0 14%, $stage-orange 38%, $subject-pink 58%, $error 100%);
  box-shadow: inset 0 -12px 20px rgba(23, 20, 26, .45);
  z-index: 1;
}
.sp__handle {
  width: 44px;
  height: 56px;
  margin-left: -22px;
  margin-top: -24px;
  border: 10px solid #b98272;
  border-radius: 50%;
  transform: translateX(calc(44px * var(--sin))) scaleX(var(--hs));
  z-index: var(--hz);
}
.sp__logo {
  width: 36px;
  height: 36px;
  margin-left: -18px;
  margin-top: -16px;
  border-radius: 50%;
  background: $stage-yellow;
  opacity: var(--lo);
  transform: translateX(calc(-44px * var(--sin))) scaleX(var(--ls));
  z-index: 2;
}

// 30도씩 열두 각도. --sin 은 손잡이 가로 위치(반지름 44px 에 곱한다),
// --hs 는 옆으로 뻗은 손잡이가 정면을 볼수록 납작해지는 정도, --ls 는 컵에 찍힌 로고가 돌아가며 눌리는 정도,
// --hz 는 손잡이가 컵 앞(2)인지 뒤(0)인지, --lo 는 로고가 이쪽을 보는지.
// 첫 칸을 60도로 잡아, 루프를 끈 정지 화면에서도 손잡이가 보이는 3/4 각도로 선다
.sp__f:nth-child(1)  { --sin: .87;  --hs: .87; --ls: .5;  --hz: 2; --lo: 0; }
.sp__f:nth-child(2)  { --sin: 1;    --hs: 1;   --ls: 0;   --hz: 2; --lo: 0; }
.sp__f:nth-child(3)  { --sin: .87;  --hs: .87; --ls: .5;  --hz: 0; --lo: 1; }
.sp__f:nth-child(4)  { --sin: .5;   --hs: .5;  --ls: .87; --hz: 0; --lo: 1; }
.sp__f:nth-child(5)  { --sin: 0;    --hs: .06; --ls: 1;   --hz: 0; --lo: 1; }
.sp__f:nth-child(6)  { --sin: -.5;  --hs: .5;  --ls: .87; --hz: 0; --lo: 1; }
.sp__f:nth-child(7)  { --sin: -.87; --hs: .87; --ls: .5;  --hz: 0; --lo: 1; }
.sp__f:nth-child(8)  { --sin: -1;   --hs: 1;   --ls: 0;   --hz: 2; --lo: 0; }
.sp__f:nth-child(9)  { --sin: -.87; --hs: .87; --ls: .5;  --hz: 2; --lo: 0; }
.sp__f:nth-child(10) { --sin: -.5;  --hs: .5;  --ls: .87; --hz: 2; --lo: 0; }
.sp__f:nth-child(11) { --sin: 0;    --hs: .06; --ls: 1;   --hz: 2; --lo: 0; }
.sp__f:nth-child(12) { --sin: .5;   --hs: .5;  --ls: .87; --hz: 2; --lo: 0; }

// ── 자동 루프 (2s) ────────────────────────────────────
// steps(12, end) 가 0/12 부터 11/12 까지 열두 칸을 정확히 밟는다.
// 열두 번째 다음이 첫 장이고 그 둘은 이어지는 각도라 한 바퀴가 매끄럽다
.sp.is-demo .sp__track {
  animation-name: sp-spin;
  animation-duration: $dur-loop;
  animation-timing-function: steps(12, end);
  animation-iteration-count: infinite;
}

@keyframes sp-spin {
  0%   { transform: translateX(0); }
  100% { transform: translateX(-100%); }
}

@media (max-width: 360px) {
  .sp__win { height: 160px; }
  .sp__body { width: 84px; height: 100px; margin-left: -42px; margin-top: -50px; }
}

@media (prefers-reduced-motion: reduce) {
  .sp.is-demo .sp__track { animation: none !important; transform: translateX(-25%); }
}

html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffd23f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.sp {
  position: relative;
}

.sp__win {
  box-sizing: border-box;
  width: 288px;
  height: 168px;
  overflow: hidden;
  border-radius: 16px;
  background: linear-gradient(#17141a, #2f2838);
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  cursor: grab;
  touch-action: none;
}

.sp__win:focus-visible {
  outline: 3px solid #17141a;
  outline-offset: 2px;
}

.sp__track {
  display: flex;
  width: 1200%;
  height: 100%;
  transform: translateX(0);
}

.sp__f {
  position: relative;
  flex: 0 0 8.3333%;
  height: 100%;
  display: grid;
  place-items: center;
}

.sp__f > i {
  position: absolute;
  left: 50%;
  top: 50%;
  display: block;
}

.sp__body {
  width: 92px;
  height: 108px;
  margin-left: -46px;
  margin-top: -54px;
  border-radius: 12px 12px 16px 16px;
  background: linear-gradient(90deg, #a96953 0 14%, #ff4d1f 38%, #ff9ebb 58%, #c2361a 100%);
  box-shadow: inset 0 -12px 20px rgba(23, 20, 26, 0.45);
  z-index: 1;
}

.sp__handle {
  width: 44px;
  height: 56px;
  margin-left: -22px;
  margin-top: -24px;
  border: 10px solid #b98272;
  border-radius: 50%;
  transform: translateX(calc(44px * var(--sin))) scaleX(var(--hs));
  z-index: var(--hz);
}

.sp__logo {
  width: 36px;
  height: 36px;
  margin-left: -18px;
  margin-top: -16px;
  border-radius: 50%;
  background: #ffd23f;
  opacity: var(--lo);
  transform: translateX(calc(-44px * var(--sin))) scaleX(var(--ls));
  z-index: 2;
}

.sp__f:nth-child(1) {
  --sin: .87;
  --hs: .87;
  --ls: .5;
  --hz: 2;
  --lo: 0;
}

.sp__f:nth-child(2) {
  --sin: 1;
  --hs: 1;
  --ls: 0;
  --hz: 2;
  --lo: 0;
}

.sp__f:nth-child(3) {
  --sin: .87;
  --hs: .87;
  --ls: .5;
  --hz: 0;
  --lo: 1;
}

.sp__f:nth-child(4) {
  --sin: .5;
  --hs: .5;
  --ls: .87;
  --hz: 0;
  --lo: 1;
}

.sp__f:nth-child(5) {
  --sin: 0;
  --hs: .06;
  --ls: 1;
  --hz: 0;
  --lo: 1;
}

.sp__f:nth-child(6) {
  --sin: -.5;
  --hs: .5;
  --ls: .87;
  --hz: 0;
  --lo: 1;
}

.sp__f:nth-child(7) {
  --sin: -.87;
  --hs: .87;
  --ls: .5;
  --hz: 0;
  --lo: 1;
}

.sp__f:nth-child(8) {
  --sin: -1;
  --hs: 1;
  --ls: 0;
  --hz: 2;
  --lo: 0;
}

.sp__f:nth-child(9) {
  --sin: -.87;
  --hs: .87;
  --ls: .5;
  --hz: 2;
  --lo: 0;
}

.sp__f:nth-child(10) {
  --sin: -.5;
  --hs: .5;
  --ls: .87;
  --hz: 2;
  --lo: 0;
}

.sp__f:nth-child(11) {
  --sin: 0;
  --hs: .06;
  --ls: 1;
  --hz: 2;
  --lo: 0;
}

.sp__f:nth-child(12) {
  --sin: .5;
  --hs: .5;
  --ls: .87;
  --hz: 2;
  --lo: 0;
}

.sp.is-demo .sp__track {
  animation-name: sp-spin;
  animation-duration: 2s;
  animation-timing-function: steps(12, end);
  animation-iteration-count: infinite;
}

@keyframes sp-spin {
  0% {
    transform: translateX(0);
  }
  100% {
    transform: translateX(-100%);
  }
}
@media (max-width: 360px) {
  .sp__win {
    height: 160px;
  }
  .sp__body {
    width: 84px;
    height: 100px;
    margin-left: -42px;
    margin-top: -50px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .sp.is-demo .sp__track {
    animation: none !important;
    transform: translateX(-25%);
  }
}

// 실제 동작: 끈 거리를 프레임 번호로 바꾼다. 열두 장이 한 바퀴다.
var sp = document.getElementById('sp');
var spWin = document.getElementById('sp-win');
var spTrack = document.getElementById('sp-track');
var SP_N = 12, SP_STEP = 18;
var spI = 0, spDrag = null;
function spPaint() {
  sp.classList.remove('is-demo');           // 사람이 손대면 자동 루프를 멈춘다
  spI = ((spI % SP_N) + SP_N) % SP_N;
  spTrack.style.transform = 'translateX(' + (-spI * 100 / SP_N) + '%)';
}
spWin.addEventListener('pointerdown', function (e) {
  spDrag = { x: e.clientX, i: spI };
  spWin.setPointerCapture(e.pointerId);
});
spWin.addEventListener('pointermove', function (e) {
  if (!spDrag) return;
  spI = spDrag.i - Math.round((e.clientX - spDrag.x) / SP_STEP);
  spPaint();
});
spWin.addEventListener('pointerup', function () { spDrag = null; });
spWin.addEventListener('keydown', function (e) {
  if (e.key !== 'ArrowLeft' && e.key !== 'ArrowRight') return;
  e.preventDefault();
  spI += e.key === 'ArrowRight' ? 1 : -1;
  spPaint();
});

import { useRef, useState } from "react";
import type { CSSProperties } from "react";
import styles from "./SpinView360.module.scss";

export type SpinView360Props = {
  label?: string;
  /** 한 바퀴를 이루는 칸 수. module.scss 의 steps(N, end) 와 같아야 한다 */
  frames?: number;
  /** 한 칸을 넘기는 데 필요한 드래그 거리(px) */
  dragStep?: number;
  /** 자동 재생 루프 (갤러리용). 사람이 손대면 꺼진다 */
  demo?: boolean;
  duration?: number;
  easing?: string;
  color?: string;
};

type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };
type DragEvt = { clientX: number; pointerId: number };
type KeyEvt = { key: string; preventDefault: () => void };

export default function SpinView360({
  label = "Mug in 360 degrees. Turn it with the arrow keys",
  frames = 12,
  dragStep = 18,
  demo = true,
  duration = 300,
  easing = "ease-out",
  color = "#17141a",
}: SpinView360Props) {
  const drag = useRef<{ x: number; i: number } | null>(null);
  const [live, setLive] = useState(demo);
  const [i, setI] = useState(0);

  function go(next: number) {
    setLive(false);
    setI(((next % frames) + frames) % frames);
  }

  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };
  const track: CSSProperties = { transform: `translateX(${(-i * 100) / frames}%)` };

  return (
    <div className={[styles.root, live ? styles.isDemo : ""].join(" ")} style={vars}>
      <div
        className={styles.win}
        tabIndex={0}
        role="img"
        aria-label={label}
        onPointerDown={(e: DragEvt) => { drag.current = { x: e.clientX, i }; }}
        onPointerMove={(e: DragEvt) => {
          const d = drag.current;
          if (!d) return;
          go(d.i - Math.round((e.clientX - d.x) / dragStep));
        }}
        onPointerUp={() => { drag.current = null; }}
        onKeyDown={(e: KeyEvt) => {
          if (e.key !== "ArrowLeft" && e.key !== "ArrowRight") return;
          e.preventDefault();
          go(i + (e.key === "ArrowRight" ? 1 : -1));
        }}
      >
        <div className={styles.track} style={live ? undefined : track}>
          {Array.from({ length: frames }, (_, k) => (
            <div className={styles.f} key={k}>
              <i className={styles.handle} />
              <i className={styles.body} />
              <i className={styles.logo} />
            </div>
          ))}
        </div>
      </div>
    </div>
  );
}