03A Paper Texture Scene With a Zigzag Edge and a Curled Corner Where a Different Shadow Falls on Each Column
The edge teeth are cut as a polygon, and the sheet is treated as a gently curved surface so each column gets its own shade. The curled corner's shadow also follows the light angle.
Best forReceipt card UIs and coupon edge decoration
TOOTH_NCURL_PXLIGHT_DEGSHADE_MAX
<main class="stage">
<div class="rc is-demo" id="rc">
<canvas class="rc__canvas" data-role="canvas" width="480" height="300" tabindex="0" aria-label="A sheet with zigzag edges and a curled corner while the light angle keeps moving and each column gets a different shadow"></canvas>
<p class="rc__status" data-role="status" aria-live="polite">The light is moving</p>
<div class="rc__tools">
<button class="rc__btn" data-role="btn" type="button" aria-pressed="false">Hold light</button>
</div>
</div>
</main>@use "../../../../site/static/demo-tokens" as *;
@include stage($stage-ink);
.rc {
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;
}
.rc__canvas {
display: block;
width: 100%;
height: 100%;
}
.rc__canvas:focus-visible {
outline: 2px solid rgba(255, 255, 255, .85);
outline-offset: -6px;
}
.rc__status {
position: absolute;
left: $sp-3;
bottom: $sp-3;
max-width: 46%;
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;
}
.rc__tools {
position: absolute;
right: $sp-3;
bottom: $sp-3;
display: flex;
gap: $sp-2;
}
.rc__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;
}
.rc__btn[aria-pressed="true"] {
background: $subject-mint;
}
.rc__btn:focus-visible {
outline: 2px solid rgba(255, 255, 255, .95);
outline-offset: 2px;
}
.rc__canvas { touch-action: none; }
@media (max-width: 340px) {
.rc__btn { font-size: 10px; padding: $sp-1 $sp-2; }
.rc__status { font-size: 10px; padding: $sp-1 $sp-2; }
}
@media (prefers-reduced-motion: reduce) {
.rc { cursor: default; }
.rc__chip { cursor: default; }
}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);
}
.rc {
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;
}
.rc__canvas {
display: block;
width: 100%;
height: 100%;
}
.rc__canvas:focus-visible {
outline: 2px solid rgba(255, 255, 255, 0.85);
outline-offset: -6px;
}
.rc__status {
position: absolute;
left: 12px;
bottom: 12px;
max-width: 46%;
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;
}
.rc__tools {
position: absolute;
right: 12px;
bottom: 12px;
display: flex;
gap: 8px;
}
.rc__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;
}
.rc__btn[aria-pressed=true] {
background: #4cd4a6;
}
.rc__btn:focus-visible {
outline: 2px solid rgba(255, 255, 255, 0.95);
outline-offset: 2px;
}
.rc__canvas {
touch-action: none;
}
@media (max-width: 340px) {
.rc__btn {
font-size: 10px;
padding: 4px 8px;
}
.rc__status {
font-size: 10px;
padding: 4px 8px;
}
}
@media (prefers-reduced-motion: reduce) {
.rc {
cursor: default;
}
.rc__chip {
cursor: default;
}
}(function () {
const root = document.getElementById("rc");
if (!root) return;
const W = 480;
const H = 300;
const FIXED_DT = 16;
// 파스텔 팔레트 — 어두운 무대 위에 밝은 종이를 얹어 명도 차로 읽힌다
const BG = [29, 26, 44];
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)]; }
// 시드 고정 난수 — 같은 시드면 언제나 같은 수열 (선형 합동 방식)
function lcg(seed) {
let s = seed >>> 0;
return function () {
s = (Math.imul(s, 1664525) + 1013904223) >>> 0;
return s / 4294967296;
};
}
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)');
function fitCanvas() {
const dpr = window.devicePixelRatio || 1;
cv.width = Math.round(W * dpr);
cv.height = Math.round(H * dpr);
ctx.setTransform(dpr, 0, 0, dpr, 0, 0);
}
function onResize() {
fitCanvas();
if (reduceQuery.matches) {
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];
}
const TOOTH_N = 18;
const CURL_PX = 74;
const LIGHT_DEG = 38;
const SHADE_MAX = 0.46;
const SWAY_DEG = 46;
const SWAY_MS = 2400;
const SHEET_W = 300;
const SHEET_T = 22;
const SHEET_B = 262;
const TXT_AUTO = 'The light is moving';
const TXT_HOLD = 'Light angle held';
const LINES = ['Moonlight Shop', 'Milk', 'Bread', 'Apples'];
const PRICES = ['', '1,200', '2,800', '3,500'];
const holdBtn = root.querySelector('[data-role="btn"]');
let clock = 0;
let manual = false;
let manualDeg = LIGHT_DEG;
let dragging = false;
const sheetX = (W - SHEET_W) / 2;
// 지금 빛이 오는 각도(도) — 자동이면 기준 각도를 중심으로 계속 흔든다
function lightDeg() {
if (manual) {
return manualDeg;
}
return LIGHT_DEG + SWAY_DEG * Math.sin((clock / SWAY_MS) * Math.PI * 2);
}
// 가로 열 하나의 음영 세기 — 종이를 부드럽게 말린 곡면으로 보고 법선과 빛 방향의 내적을 쓴다
function shadeAt(col, deg) {
const u = col / SHEET_W * 2 - 1;
const slope = u * 0.62;
const nx = -slope;
const nz = Math.sqrt(1 - Math.min(0.99, slope * slope));
const rad = deg * Math.PI / 180;
const lx = Math.sin(rad);
const lz = Math.cos(rad);
const dot = clamp(nx * lx + nz * lz, 0, 1);
return (1 - dot) * SHADE_MAX;
}
function edgeY(i, top) {
const amp = 7;
const y = top ? SHEET_T : SHEET_B;
const up = (i % 2 === 0) === top;
return y + (up ? -amp * 0.4 : amp * 0.8);
}
function step() {
clock += FIXED_DT;
}
function settle() {
clock = SWAY_MS * 0.16;
}
function outline(ctx2, dx, dy) {
ctx2.beginPath();
const n = TOOTH_N;
ctx2.moveTo(sheetX + dx, edgeY(0, true) + dy);
for (let i = 1; i <= n; i += 1) {
ctx2.lineTo(sheetX + dx + (SHEET_W * i) / n, edgeY(i, true) + dy);
}
// 오른쪽 아래 모서리는 말려 올라간 만큼 잘라 낸다
ctx2.lineTo(sheetX + dx + SHEET_W, SHEET_B - CURL_PX + dy);
ctx2.lineTo(sheetX + dx + SHEET_W - CURL_PX, SHEET_B + dy);
for (let i = n - 1; i >= 0; i -= 1) {
ctx2.lineTo(sheetX + dx + (SHEET_W * i) / n, edgeY(i, false) + dy);
}
ctx2.closePath();
}
function draw() {
const deg = lightDeg();
ctx.fillStyle = rgba(BG, 1);
ctx.fillRect(0, 0, W, H);
// 바닥 그림자 — 빛 반대쪽으로 밀려 나간다
const rad = deg * Math.PI / 180;
const sx = -Math.sin(rad) * 14;
ctx.fillStyle = rgba([10, 8, 22], 0.45);
outline(ctx, sx + 4, 10);
ctx.fill();
// 종이 본체
ctx.fillStyle = rgba(PAPER, 1);
outline(ctx, 0, 0);
ctx.fill();
ctx.save();
outline(ctx, 0, 0);
ctx.clip();
// 열마다 다른 음영
const colW = 3;
for (let c = 0; c < SHEET_W; c += colW) {
const s = shadeAt(c + colW / 2, deg);
ctx.fillStyle = rgba(INK, s);
ctx.fillRect(sheetX + c, 0, colW, H);
}
// 가로 결과 글자
ctx.fillStyle = rgba(INK, 0.06);
for (let y = SHEET_T; y < SHEET_B; y += 8) {
ctx.fillRect(sheetX, y, SHEET_W, 1);
}
ctx.font = '600 13px "Noto Sans KR", ui-monospace, monospace';
for (let i = 0; i < LINES.length; i += 1) {
const y = 62 + i * 30;
ctx.fillStyle = rgba(INK, 0.9);
ctx.textAlign = i === 0 ? 'center' : 'left';
ctx.fillText(LINES[i], i === 0 ? sheetX + SHEET_W / 2 : sheetX + 26, y);
if (PRICES[i]) {
ctx.textAlign = 'right';
ctx.fillText(PRICES[i], sheetX + SHEET_W - 26, y);
}
}
// 말린 모서리가 종이 위에 던지는 그림자 — 빛이 기울면 길이와 방향이 바뀐다
const cx = sheetX + SHEET_W;
const cy = SHEET_B;
const throwX = Math.sin(rad) * 26;
ctx.fillStyle = rgba([40, 30, 60], 0.3);
ctx.beginPath();
ctx.moveTo(cx - CURL_PX, cy);
ctx.lineTo(cx, cy - CURL_PX);
ctx.lineTo(cx - CURL_PX * 0.55 - throwX, cy - CURL_PX * 0.55 - 12);
ctx.closePath();
ctx.fill();
ctx.restore();
// 접힌 날개 — 종이 뒷면이 빛을 받아 밝게 보인다
const flap = ctx.createLinearGradient(cx - CURL_PX, cy, cx, cy - CURL_PX);
const lit = 0.5 + 0.5 * Math.cos(rad - 0.9);
flap.addColorStop(0, rgba(mix(PAPER, LILAC, 0.5), 1));
flap.addColorStop(1, rgba(mix(PAPER, [255, 255, 255], 0.5 * lit), 1));
ctx.fillStyle = flap;
ctx.beginPath();
ctx.moveTo(cx - CURL_PX, cy);
ctx.lineTo(cx, cy - CURL_PX);
ctx.lineTo(cx - CURL_PX * 0.86, cy - CURL_PX * 0.86 + 4);
ctx.lineTo(cx - CURL_PX - 6, cy - 6);
ctx.closePath();
ctx.fill();
// 빛 방향 표시 — 위쪽 반원에서 해가 돈다
const hx = W / 2 + Math.sin(rad) * 190;
const hy = 18 - Math.cos(rad) * 6;
ctx.fillStyle = rgba(PEACH, 0.95);
ctx.beginPath();
ctx.arc(clamp(hx, 14, W - 14), hy + 6, 7, 0, Math.PI * 2);
ctx.fill();
}
function setHold(on) {
// 고정하는 순간의 각도를 먼저 읽는다 — manual 을 먼저 바꾸면 옛 manualDeg 로 튄다
if (on && !manual) {
manualDeg = lightDeg();
}
manual = on;
if (holdBtn) {
holdBtn.setAttribute('aria-pressed', on ? 'true' : 'false');
}
status.textContent = on ? TXT_HOLD : TXT_AUTO;
if (reduceQuery.matches) {
draw();
}
}
if (holdBtn) {
holdBtn.addEventListener('click', function () { setHold(!manual); });
}
cv.addEventListener('pointerdown', function (ev) {
dragging = true;
cv.setPointerCapture(ev.pointerId);
setHold(true);
manualDeg = clamp((toScene(ev)[0] / W - 0.5) * 120, -60, 60);
if (reduceQuery.matches) {
draw();
}
});
cv.addEventListener('pointermove', function (ev) {
if (!dragging) {
return;
}
manualDeg = clamp((toScene(ev)[0] / W - 0.5) * 120, -60, 60);
if (reduceQuery.matches) {
draw();
}
});
cv.addEventListener('pointerup', function () { dragging = false; });
cv.addEventListener('pointercancel', function () { dragging = false; });
cv.addEventListener('keydown', function (ev) {
if (ev.key === 'ArrowLeft' || ev.key === 'ArrowRight') {
ev.preventDefault();
if (!manual) {
setHold(true);
}
manualDeg = clamp(manualDeg + (ev.key === 'ArrowLeft' ? -6 : 6), -90, 90);
if (reduceQuery.matches) {
draw();
}
}
});
let rafId = 0;
let lastTs = -1;
let acc = 0;
function frame(ts) {
if (lastTs < 0) {
lastTs = ts;
}
acc += Math.min(ts - lastTs, 100);
lastTs = ts;
let n = 0;
while (acc >= FIXED_DT && n < 6) {
step();
acc -= FIXED_DT;
n += 1;
}
draw();
rafId = window.requestAnimationFrame(frame);
}
if (reduceQuery.matches) {
settle();
draw();
}
else {
rafId = window.requestAnimationFrame(frame);
}
return function () {
window.cancelAnimationFrame(rafId);
window.removeEventListener('resize', onResize);
};
})();// RecZigzagEdgePaperCurlShadow - vanilla 판(03-rec-zigzag-edge-paper-curl-shadow) 의 React 포트. 같은 계산을 useEffect 안에서 돌린다.
import { useEffect, useRef } from "react";
import styles from "./RecZigzagEdgePaperCurlShadow.module.scss";
const cx = (s: string): string => s.split(" ").map((n) => styles[n] ?? n).join(" ");
export default function RecZigzagEdgePaperCurlShadow() {
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 종이를 얹어 명도 차로 읽힌다
const BG: RGB = [29, 26, 44];
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)]; }
// 시드 고정 난수 — 같은 시드면 언제나 같은 수열 (선형 합동 방식)
function lcg(seed: number): () => number {
let s = seed >>> 0;
return function (): number {
s = (Math.imul(s, 1664525) + 1013904223) >>> 0;
return s / 4294967296;
};
}
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)');
function fitCanvas(): void {
const dpr = window.devicePixelRatio || 1;
cv.width = Math.round(W * dpr);
cv.height = Math.round(H * dpr);
ctx.setTransform(dpr, 0, 0, dpr, 0, 0);
}
function onResize(): void {
fitCanvas();
if (reduceQuery.matches) { 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];
}
const TOOTH_N = 18;
const CURL_PX = 74;
const LIGHT_DEG = 38;
const SHADE_MAX = 0.46;
const SWAY_DEG = 46;
const SWAY_MS = 2400;
const SHEET_W = 300;
const SHEET_T = 22;
const SHEET_B = 262;
const TXT_AUTO = '빛이 움직이는 중';
const TXT_HOLD = '빛 각도 고정';
const LINES: string[] = ['달빛 상점', '우유', '식빵', '사과'];
const PRICES: string[] = ['', '1,200', '2,800', '3,500'];
const holdBtn = root.querySelector('[data-role="btn"]') as HTMLButtonElement | null;
let clock = 0;
let manual = false;
let manualDeg = LIGHT_DEG;
let dragging = false;
const sheetX = (W - SHEET_W) / 2;
// 지금 빛이 오는 각도(도) — 자동이면 기준 각도를 중심으로 계속 흔든다
function lightDeg(): number {
if (manual) { return manualDeg; }
return LIGHT_DEG + SWAY_DEG * Math.sin((clock / SWAY_MS) * Math.PI * 2);
}
// 가로 열 하나의 음영 세기 — 종이를 부드럽게 말린 곡면으로 보고 법선과 빛 방향의 내적을 쓴다
function shadeAt(col: number, deg: number): number {
const u = col / SHEET_W * 2 - 1;
const slope = u * 0.62;
const nx = -slope;
const nz = Math.sqrt(1 - Math.min(0.99, slope * slope));
const rad = deg * Math.PI / 180;
const lx = Math.sin(rad);
const lz = Math.cos(rad);
const dot = clamp(nx * lx + nz * lz, 0, 1);
return (1 - dot) * SHADE_MAX;
}
function edgeY(i: number, top: boolean): number {
const amp = 7;
const y = top ? SHEET_T : SHEET_B;
const up = (i % 2 === 0) === top;
return y + (up ? -amp * 0.4 : amp * 0.8);
}
function step(): void {
clock += FIXED_DT;
}
function settle(): void {
clock = SWAY_MS * 0.16;
}
function outline(ctx2: CanvasRenderingContext2D, dx: number, dy: number): void {
ctx2.beginPath();
const n = TOOTH_N;
ctx2.moveTo(sheetX + dx, edgeY(0, true) + dy);
for (let i = 1; i <= n; i += 1) { ctx2.lineTo(sheetX + dx + (SHEET_W * i) / n, edgeY(i, true) + dy); }
// 오른쪽 아래 모서리는 말려 올라간 만큼 잘라 낸다
ctx2.lineTo(sheetX + dx + SHEET_W, SHEET_B - CURL_PX + dy);
ctx2.lineTo(sheetX + dx + SHEET_W - CURL_PX, SHEET_B + dy);
for (let i = n - 1; i >= 0; i -= 1) { ctx2.lineTo(sheetX + dx + (SHEET_W * i) / n, edgeY(i, false) + dy); }
ctx2.closePath();
}
function draw(): void {
const deg = lightDeg();
ctx.fillStyle = rgba(BG, 1);
ctx.fillRect(0, 0, W, H);
// 바닥 그림자 — 빛 반대쪽으로 밀려 나간다
const rad = deg * Math.PI / 180;
const sx = -Math.sin(rad) * 14;
ctx.fillStyle = rgba([10, 8, 22], 0.45);
outline(ctx, sx + 4, 10);
ctx.fill();
// 종이 본체
ctx.fillStyle = rgba(PAPER, 1);
outline(ctx, 0, 0);
ctx.fill();
ctx.save();
outline(ctx, 0, 0);
ctx.clip();
// 열마다 다른 음영
const colW = 3;
for (let c = 0; c < SHEET_W; c += colW) {
const s = shadeAt(c + colW / 2, deg);
ctx.fillStyle = rgba(INK, s);
ctx.fillRect(sheetX + c, 0, colW, H);
}
// 가로 결과 글자
ctx.fillStyle = rgba(INK, 0.06);
for (let y = SHEET_T; y < SHEET_B; y += 8) { ctx.fillRect(sheetX, y, SHEET_W, 1); }
ctx.font = '600 13px "Noto Sans KR", ui-monospace, monospace';
for (let i = 0; i < LINES.length; i += 1) {
const y = 62 + i * 30;
ctx.fillStyle = rgba(INK, 0.9);
ctx.textAlign = i === 0 ? 'center' : 'left';
ctx.fillText(LINES[i], i === 0 ? sheetX + SHEET_W / 2 : sheetX + 26, y);
if (PRICES[i]) {
ctx.textAlign = 'right';
ctx.fillText(PRICES[i], sheetX + SHEET_W - 26, y);
}
}
// 말린 모서리가 종이 위에 던지는 그림자 — 빛이 기울면 길이와 방향이 바뀐다
const cx = sheetX + SHEET_W;
const cy = SHEET_B;
const throwX = Math.sin(rad) * 26;
ctx.fillStyle = rgba([40, 30, 60], 0.3);
ctx.beginPath();
ctx.moveTo(cx - CURL_PX, cy);
ctx.lineTo(cx, cy - CURL_PX);
ctx.lineTo(cx - CURL_PX * 0.55 - throwX, cy - CURL_PX * 0.55 - 12);
ctx.closePath();
ctx.fill();
ctx.restore();
// 접힌 날개 — 종이 뒷면이 빛을 받아 밝게 보인다
const flap = ctx.createLinearGradient(cx - CURL_PX, cy, cx, cy - CURL_PX);
const lit = 0.5 + 0.5 * Math.cos(rad - 0.9);
flap.addColorStop(0, rgba(mix(PAPER, LILAC, 0.5), 1));
flap.addColorStop(1, rgba(mix(PAPER, [255, 255, 255], 0.5 * lit), 1));
ctx.fillStyle = flap;
ctx.beginPath();
ctx.moveTo(cx - CURL_PX, cy);
ctx.lineTo(cx, cy - CURL_PX);
ctx.lineTo(cx - CURL_PX * 0.86, cy - CURL_PX * 0.86 + 4);
ctx.lineTo(cx - CURL_PX - 6, cy - 6);
ctx.closePath();
ctx.fill();
// 빛 방향 표시 — 위쪽 반원에서 해가 돈다
const hx = W / 2 + Math.sin(rad) * 190;
const hy = 18 - Math.cos(rad) * 6;
ctx.fillStyle = rgba(PEACH, 0.95);
ctx.beginPath();
ctx.arc(clamp(hx, 14, W - 14), hy + 6, 7, 0, Math.PI * 2);
ctx.fill();
}
function setHold(on: boolean): void {
// 고정하는 순간의 각도를 먼저 읽는다 — manual 을 먼저 바꾸면 옛 manualDeg 로 튄다
if (on && !manual) { manualDeg = lightDeg(); }
manual = on;
if (holdBtn) { holdBtn.setAttribute('aria-pressed', on ? 'true' : 'false'); }
status.textContent = on ? TXT_HOLD : TXT_AUTO;
if (reduceQuery.matches) { draw(); }
}
if (holdBtn) {
holdBtn.addEventListener('click', function (): void { setHold(!manual); });
}
cv.addEventListener('pointerdown', function (ev: PointerEvent): void {
dragging = true;
cv.setPointerCapture(ev.pointerId);
setHold(true);
manualDeg = clamp((toScene(ev)[0] / W - 0.5) * 120, -60, 60);
if (reduceQuery.matches) { draw(); }
});
cv.addEventListener('pointermove', function (ev: PointerEvent): void {
if (!dragging) { return; }
manualDeg = clamp((toScene(ev)[0] / W - 0.5) * 120, -60, 60);
if (reduceQuery.matches) { draw(); }
});
cv.addEventListener('pointerup', function (): void { dragging = false; });
cv.addEventListener('pointercancel', function (): void { dragging = false; });
cv.addEventListener('keydown', function (ev: KeyboardEvent): void {
if (ev.key === 'ArrowLeft' || ev.key === 'ArrowRight') {
ev.preventDefault();
if (!manual) { setHold(true); }
manualDeg = clamp(manualDeg + (ev.key === 'ArrowLeft' ? -6 : 6), -90, 90);
if (reduceQuery.matches) { draw(); }
}
});
let rafId = 0;
let lastTs = -1;
let acc = 0;
function frame(ts: number): void {
if (lastTs < 0) { lastTs = ts; }
acc += Math.min(ts - lastTs, 100);
lastTs = ts;
let n = 0;
while (acc >= FIXED_DT && n < 6) {
step();
acc -= FIXED_DT;
n += 1;
}
draw();
rafId = window.requestAnimationFrame(frame);
}
if (reduceQuery.matches) {
settle();
draw();
} else {
rafId = window.requestAnimationFrame(frame);
}
return function (): void {
window.cancelAnimationFrame(rafId);
window.removeEventListener('resize', onResize);
};
}, []);
return (
<div className={cx("rc") + " is-demo"} ref={rootRef}>
<canvas className={cx("rc__canvas")} data-role="canvas" width={480} height={300} tabIndex={0} aria-label="톱니 가장자리와 말린 모서리가 있는 종이 위로 빛 각도가 계속 움직이며 열마다 다른 그림자가 지나가는 장면"></canvas>
<p className={cx("rc__status")} data-role="status" aria-live="polite">빛이 움직이는 중</p>
<div className={cx("rc__tools")}>
<button className={cx("rc__btn")} data-role="btn" type="button" aria-pressed="false">빛 고정</button>
</div>
</div>
);
}03 A Paper Texture Scene With a Zigzag Edge and a Curled Corner Where a Different Shadow Falls on Each Column — Measured area 36.52% · moving frames 23/23Original by GODRICH · SCSS and React ship in the zip · CSS Receipt: 9 Thermal Print and Tear-Off Scenes
The post this demo lives in
CSS Receipt: 9 Thermal Print and Tear-Off ScenesA css receipt layers print-head shiver, paper curl and a rolling total — scene 01 adds a tremor to each line step, and s See all demos in this post
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