07Thermal-Paper Text That Darkens Only Where Heat Touched and Fades Unevenly Over Time Following a Noise Map
Heat is stacked onto a text mask (spots without text get only a faint warmth) and a noise map sets a different fade speed at each spot. When a value drops below the cutoff, that point returns to the paper color.
Best forAged receipt looks and faded document effects
HEAT_GAINFADE_RATENOISE_SCALECUTOFF
<main class="stage">
<div class="rc is-demo" id="rc">
<canvas class="rc__canvas" data-role="canvas" width="480" height="300" aria-label="Thermal-paper text fading away at a different speed in each spot according to a noise map"></canvas>
<p class="rc__status" data-role="status" aria-live="polite">Printing</p>
<div class="rc__tools">
<button class="rc__btn" data-role="btn" type="button">Print again</button>
<button class="rc__btn" data-role="sun" type="button" aria-pressed="false">Sunlight</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;
}
@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;
}
@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 HEAT_GAIN = 1;
const FADE_RATE = 0.4;
const NOISE_SCALE = 30;
const CUTOFF = 0.25;
const SPREAD = 2.4;
const PRINT_MS = 700;
const CYCLE_MS = 2800;
const HALO = 0.24;
const SUN_X = 3;
const PW = 280;
const PX = (W - PW) / 2;
const TXT_PRINT = 'Printing';
const TXT_FADE = 'Fading';
const TXT_GONE = 'Fully faded';
const TXT_LINES = ['Moonlight Shop', 'Milk', 'Bread', 'Apples', 'Eggs', 'Tangerines', 'Total', 'Thank you'];
const TXT_PRICES = ['', '1,200', '2,800', '3,500', '4,100', '1,900', '13,500', ''];
const againBtn = root.querySelector('[data-role="btn"]');
const sunBtn = root.querySelector('[data-role="sun"]');
const off = document.createElement('canvas');
off.width = PW;
off.height = H;
const offCtxRaw = off.getContext('2d');
if (!offCtxRaw) {
return;
}
const offCtx = offCtxRaw;
const img = offCtx.createImageData(PW, H);
const mask = new Float32Array(PW * H);
const heat = new Float32Array(PW * H);
const rate = new Float32Array(PW * H);
let front = 0;
let phaseT = 0;
let phase = 'print';
let sun = false;
let clock = 0;
function hash2(x, y) {
let h = (Math.imul(x | 0, 374761393) + Math.imul(y | 0, 668265263) + 1442695041) | 0;
h = Math.imul(h ^ (h >>> 13), 1274126177);
h ^= h >>> 16;
return (h >>> 0) / 4294967296;
}
// 값 노이즈 — 격자점 해시 네 개를 부드럽게 섞는다
function noise2(x, y) {
const xi = Math.floor(x);
const yi = Math.floor(y);
const fx = smooth(x - xi);
const fy = smooth(y - yi);
const a = hash2(xi, yi);
const b = hash2(xi + 1, yi);
const c = hash2(xi, yi + 1);
const d = hash2(xi + 1, yi + 1);
return lerp(lerp(a, b, fx), lerp(c, d, fx), fy);
}
// 한 자리의 바램 속도(초당 열 감소량) — 지도 값 n(0~1)이 클수록 빨리 바랜다
function decayAt(n) {
return FADE_RATE * (1 + SPREAD * n);
}
// 바램 속도 지도 — 위치마다 다른 값 (큰 덩이 + 잔 무늬)
function buildRate() {
for (let y = 0; y < H; y += 1) {
for (let x = 0; x < PW; x += 1) {
const n = 0.7 * noise2(x / NOISE_SCALE, y / NOISE_SCALE) + 0.3 * noise2(x / (NOISE_SCALE * 0.35) + 9, y / (NOISE_SCALE * 0.35) + 4);
rate[y * PW + x] = n;
}
}
}
// 글자 마스크 — 한 번만 그려서 읽는다 (한 번뿐이라 틱마다 읽지 않는다)
function buildMask() {
offCtx.clearRect(0, 0, PW, H);
offCtx.fillStyle = '#ffffff';
offCtx.font = '700 17px "Noto Sans KR", ui-monospace, monospace';
offCtx.textBaseline = 'middle';
for (let i = 0; i < TXT_LINES.length; i += 1) {
const y = 28 + i * 34;
offCtx.textAlign = i === 0 || i === TXT_LINES.length - 1 ? 'center' : 'left';
offCtx.fillText(TXT_LINES[i], i === 0 || i === TXT_LINES.length - 1 ? PW / 2 : 22, y);
if (TXT_PRICES[i]) {
offCtx.textAlign = 'right';
offCtx.fillText(TXT_PRICES[i], PW - 22, y);
}
}
offCtx.fillRect(18, 28 + 6 * 34 - 17, PW - 36, 2);
const d = offCtx.getImageData(0, 0, PW, H).data;
for (let i = 0; i < PW * H; i += 1) {
mask[i] = d[i * 4 + 3] / 255;
}
}
function restart() {
heat.fill(0);
front = 0;
phase = 'print';
phaseT = 0;
status.textContent = TXT_PRINT;
}
function step() {
clock += FIXED_DT;
phaseT += FIXED_DT;
const dt = FIXED_DT / 1000;
// 인쇄 머리가 위에서 아래로 지나가며 열을 쌓는다
if (phase === 'print') {
const nf = Math.min(H, Math.round((phaseT / PRINT_MS) * H));
for (let y = front; y < nf; y += 1) {
for (let x = 0; x < PW; x += 1) {
const m = mask[y * PW + x];
heat[y * PW + x] = m > 0.05 ? Math.min(1.2, HEAT_GAIN * m) : HALO;
}
}
front = nf;
if (phaseT >= PRINT_MS) {
phase = 'fade';
status.textContent = TXT_FADE;
}
}
const mul = (sun ? SUN_X : 1) * dt;
let alive = 0;
for (let i = 0; i < PW * H; i += 1) {
const h = heat[i];
if (h <= 0) {
continue;
}
const nh = h - mul * decayAt(rate[i]);
heat[i] = nh > 0 ? nh : 0;
if (nh > CUTOFF) {
alive += 1;
}
}
if (phase === 'fade' && alive === 0 && !gone) {
gone = true;
status.textContent = TXT_GONE;
}
if (phaseT >= CYCLE_MS) {
gone = false;
restart();
}
}
let gone = false;
function settle() {
for (let i = 0; i < PW * H; i += 1) {
heat[i] = mask[i];
}
phase = 'fade';
status.textContent = TXT_FADE;
}
function paint() {
const d = img.data;
for (let y = 0; y < H; y += 1) {
for (let x = 0; x < PW; x += 1) {
const i = y * PW + x;
const h = heat[i];
// 종이 바탕에도 지도가 옅게 비친다
const base = mix(PAPER, PEACH, rate[i] * 0.16);
let r = base[0];
let g = base[1];
let b = base[2];
if (h > 0 && h <= CUTOFF) {
// 글자가 없는 자리도 옅게 달아올랐다 식는다 — 바램 지도가 색으로 드러난다
const w = (h / CUTOFF) * 0.55;
r = lerp(r, 238, w);
g = lerp(g, 186, w);
b = lerp(b, 150, w);
}
else if (h > CUTOFF) {
const a = smooth((h - CUTOFF) / 0.55);
const warm = a;
const k2 = a * a;
r = lerp(r, 205, warm * 0.8);
g = lerp(g, 150, warm * 0.8);
b = lerp(b, 135, warm * 0.8);
r = lerp(r, INK[0], k2);
g = lerp(g, INK[1], k2);
b = lerp(b, INK[2], k2);
}
// 가장자리 음영
const e = Math.min(x, PW - 1 - x);
const sh = e < 10 ? 0.9 + 0.1 * (e / 10) : 1;
d[i * 4] = r * sh;
d[i * 4 + 1] = g * sh;
d[i * 4 + 2] = b * sh;
d[i * 4 + 3] = 255;
}
}
offCtx.putImageData(img, 0, 0);
}
function draw() {
ctx.fillStyle = rgba(BG, 1);
ctx.fillRect(0, 0, W, H);
ctx.fillStyle = rgba([10, 8, 22], 0.45);
ctx.fillRect(PX + 7, 0, PW, H);
paint();
ctx.imageSmoothingEnabled = false;
ctx.drawImage(off, PX, 0);
ctx.fillStyle = rgba(mix(BG, LILAC, 0.14), 1);
ctx.fillRect(0, H - 28, W, 28);
// 인쇄 머리 선
if (phase === 'print') {
ctx.fillStyle = rgba(PINK, 0.9);
ctx.fillRect(PX - 16, front - 1, PW + 32, 3);
}
}
buildRate();
buildMask();
if (againBtn) {
againBtn.addEventListener('click', function () {
gone = false;
restart();
if (reduceQuery.matches) {
settle();
draw();
}
});
}
if (sunBtn) {
sunBtn.addEventListener('click', function () {
sun = !sun;
sunBtn.setAttribute('aria-pressed', sun ? 'true' : 'false');
if (reduceQuery.matches) {
draw();
}
});
}
restart();
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);
};
})();// RecThermalFadeNoiseBurnMap - vanilla 판(07-rec-thermal-fade-noise-burn-map) 의 React 포트. 같은 계산을 useEffect 안에서 돌린다.
import { useEffect, useRef } from "react";
import styles from "./RecThermalFadeNoiseBurnMap.module.scss";
const cx = (s: string): string => s.split(" ").map((n) => styles[n] ?? n).join(" ");
export default function RecThermalFadeNoiseBurnMap() {
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 HEAT_GAIN = 1;
const FADE_RATE = 0.4;
const NOISE_SCALE = 30;
const CUTOFF = 0.25;
const SPREAD = 2.4;
const PRINT_MS = 700;
const CYCLE_MS = 2800;
const HALO = 0.24;
const SUN_X = 3;
const PW = 280;
const PX = (W - PW) / 2;
const TXT_PRINT = '인쇄 중';
const TXT_FADE = '바래는 중';
const TXT_GONE = '다 바램';
const TXT_LINES: string[] = ['달빛 상점', '우유', '식빵', '사과', '달걀', '귤', '합계', '감사합니다'];
const TXT_PRICES: string[] = ['', '1,200', '2,800', '3,500', '4,100', '1,900', '13,500', ''];
const againBtn = root.querySelector('[data-role="btn"]') as HTMLButtonElement | null;
const sunBtn = root.querySelector('[data-role="sun"]') as HTMLButtonElement | null;
const off = document.createElement('canvas');
off.width = PW;
off.height = H;
const offCtxRaw = off.getContext('2d');
if (!offCtxRaw) { return; }
const offCtx: CanvasRenderingContext2D = offCtxRaw;
const img = offCtx.createImageData(PW, H);
const mask = new Float32Array(PW * H);
const heat = new Float32Array(PW * H);
const rate = new Float32Array(PW * H);
let front = 0;
let phaseT = 0;
let phase = 'print';
let sun = false;
let clock = 0;
function hash2(x: number, y: number): number {
let h = (Math.imul(x | 0, 374761393) + Math.imul(y | 0, 668265263) + 1442695041) | 0;
h = Math.imul(h ^ (h >>> 13), 1274126177);
h ^= h >>> 16;
return (h >>> 0) / 4294967296;
}
// 값 노이즈 — 격자점 해시 네 개를 부드럽게 섞는다
function noise2(x: number, y: number): number {
const xi = Math.floor(x);
const yi = Math.floor(y);
const fx = smooth(x - xi);
const fy = smooth(y - yi);
const a = hash2(xi, yi);
const b = hash2(xi + 1, yi);
const c = hash2(xi, yi + 1);
const d = hash2(xi + 1, yi + 1);
return lerp(lerp(a, b, fx), lerp(c, d, fx), fy);
}
// 한 자리의 바램 속도(초당 열 감소량) — 지도 값 n(0~1)이 클수록 빨리 바랜다
function decayAt(n: number): number {
return FADE_RATE * (1 + SPREAD * n);
}
// 바램 속도 지도 — 위치마다 다른 값 (큰 덩이 + 잔 무늬)
function buildRate(): void {
for (let y = 0; y < H; y += 1) {
for (let x = 0; x < PW; x += 1) {
const n = 0.7 * noise2(x / NOISE_SCALE, y / NOISE_SCALE) + 0.3 * noise2(x / (NOISE_SCALE * 0.35) + 9, y / (NOISE_SCALE * 0.35) + 4);
rate[y * PW + x] = n;
}
}
}
// 글자 마스크 — 한 번만 그려서 읽는다 (한 번뿐이라 틱마다 읽지 않는다)
function buildMask(): void {
offCtx.clearRect(0, 0, PW, H);
offCtx.fillStyle = '#ffffff';
offCtx.font = '700 17px "Noto Sans KR", ui-monospace, monospace';
offCtx.textBaseline = 'middle';
for (let i = 0; i < TXT_LINES.length; i += 1) {
const y = 28 + i * 34;
offCtx.textAlign = i === 0 || i === TXT_LINES.length - 1 ? 'center' : 'left';
offCtx.fillText(TXT_LINES[i], i === 0 || i === TXT_LINES.length - 1 ? PW / 2 : 22, y);
if (TXT_PRICES[i]) {
offCtx.textAlign = 'right';
offCtx.fillText(TXT_PRICES[i], PW - 22, y);
}
}
offCtx.fillRect(18, 28 + 6 * 34 - 17, PW - 36, 2);
const d = offCtx.getImageData(0, 0, PW, H).data;
for (let i = 0; i < PW * H; i += 1) { mask[i] = d[i * 4 + 3] / 255; }
}
function restart(): void {
heat.fill(0);
front = 0;
phase = 'print';
phaseT = 0;
status.textContent = TXT_PRINT;
}
function step(): void {
clock += FIXED_DT;
phaseT += FIXED_DT;
const dt = FIXED_DT / 1000;
// 인쇄 머리가 위에서 아래로 지나가며 열을 쌓는다
if (phase === 'print') {
const nf = Math.min(H, Math.round((phaseT / PRINT_MS) * H));
for (let y = front; y < nf; y += 1) {
for (let x = 0; x < PW; x += 1) {
const m = mask[y * PW + x];
heat[y * PW + x] = m > 0.05 ? Math.min(1.2, HEAT_GAIN * m) : HALO;
}
}
front = nf;
if (phaseT >= PRINT_MS) { phase = 'fade'; status.textContent = TXT_FADE; }
}
const mul = (sun ? SUN_X : 1) * dt;
let alive = 0;
for (let i = 0; i < PW * H; i += 1) {
const h = heat[i];
if (h <= 0) { continue; }
const nh = h - mul * decayAt(rate[i]);
heat[i] = nh > 0 ? nh : 0;
if (nh > CUTOFF) { alive += 1; }
}
if (phase === 'fade' && alive === 0 && !gone) {
gone = true;
status.textContent = TXT_GONE;
}
if (phaseT >= CYCLE_MS) { gone = false; restart(); }
}
let gone = false;
function settle(): void {
for (let i = 0; i < PW * H; i += 1) { heat[i] = mask[i]; }
phase = 'fade';
status.textContent = TXT_FADE;
}
function paint(): void {
const d = img.data;
for (let y = 0; y < H; y += 1) {
for (let x = 0; x < PW; x += 1) {
const i = y * PW + x;
const h = heat[i];
// 종이 바탕에도 지도가 옅게 비친다
const base = mix(PAPER, PEACH, rate[i] * 0.16);
let r = base[0];
let g = base[1];
let b = base[2];
if (h > 0 && h <= CUTOFF) {
// 글자가 없는 자리도 옅게 달아올랐다 식는다 — 바램 지도가 색으로 드러난다
const w = (h / CUTOFF) * 0.55;
r = lerp(r, 238, w);
g = lerp(g, 186, w);
b = lerp(b, 150, w);
} else if (h > CUTOFF) {
const a = smooth((h - CUTOFF) / 0.55);
const warm = a;
const k2 = a * a;
r = lerp(r, 205, warm * 0.8);
g = lerp(g, 150, warm * 0.8);
b = lerp(b, 135, warm * 0.8);
r = lerp(r, INK[0], k2);
g = lerp(g, INK[1], k2);
b = lerp(b, INK[2], k2);
}
// 가장자리 음영
const e = Math.min(x, PW - 1 - x);
const sh = e < 10 ? 0.9 + 0.1 * (e / 10) : 1;
d[i * 4] = r * sh;
d[i * 4 + 1] = g * sh;
d[i * 4 + 2] = b * sh;
d[i * 4 + 3] = 255;
}
}
offCtx.putImageData(img, 0, 0);
}
function draw(): void {
ctx.fillStyle = rgba(BG, 1);
ctx.fillRect(0, 0, W, H);
ctx.fillStyle = rgba([10, 8, 22], 0.45);
ctx.fillRect(PX + 7, 0, PW, H);
paint();
ctx.imageSmoothingEnabled = false;
ctx.drawImage(off, PX, 0);
ctx.fillStyle = rgba(mix(BG, LILAC, 0.14), 1);
ctx.fillRect(0, H - 28, W, 28);
// 인쇄 머리 선
if (phase === 'print') {
ctx.fillStyle = rgba(PINK, 0.9);
ctx.fillRect(PX - 16, front - 1, PW + 32, 3);
}
}
buildRate();
buildMask();
if (againBtn) {
againBtn.addEventListener('click', function (): void {
gone = false;
restart();
if (reduceQuery.matches) { settle(); draw(); }
});
}
if (sunBtn) {
sunBtn.addEventListener('click', function (): void {
sun = !sun;
sunBtn.setAttribute('aria-pressed', sun ? 'true' : 'false');
if (reduceQuery.matches) { draw(); }
});
}
restart();
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} aria-label="감열지 글자가 노이즈 지도에 따라 위치마다 다른 속도로 바래 사라지는 장면"></canvas>
<p className={cx("rc__status")} data-role="status" aria-live="polite">인쇄 중</p>
<div className={cx("rc__tools")}>
<button className={cx("rc__btn")} data-role="btn" type="button">다시 인쇄</button>
<button className={cx("rc__btn")} data-role="sun" type="button" aria-pressed="false">햇빛 쬐기</button>
</div>
</div>
);
}07 Thermal-Paper Text That Darkens Only Where Heat Touched and Fades Unevenly Over Time Following a Noise Map — Measured area 40.473% · moving frames 18/23Original 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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