09A Responsive Signal That Ends Green When Cars Stop Coming and Extends It While They Do
When the gap between cars crossing the detector exceeds 60 frames the green is withdrawn; otherwise each car pushes the limit to 50 frames from now, never past 300 frames in total, and each extension drops a dot on the bar.
Best forA smart-traffic service intro
GAP_THRESHOLDEXTEND_STEPMAX_GREENDETECTOR_X
<main class="stage">
<div class="sc is-demo" id="scRoot">
<canvas class="sc__canvas" id="scCanvas" width="480" height="300" tabindex="0" aria-label="A Responsive Signal That Ends Green When Cars Stop Coming and Extends It While They Do"></canvas>
<p class="sc__status" id="scStatus" aria-live="polite">Green — go</p>
<button class="sc__btn" id="scBtn" type="button">Pause</button>
<p class="sc__caption">A Responsive Signal That Ends Green When Cars Stop Coming and Extends It While They Do</p>
</div>
</main>@use "../../../../site/static/demo-tokens" as *;
@include stage($stage-ink);
.sc {
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;
}
.sc__canvas {
display: block;
width: 100%;
height: 100%;
touch-action: none;
}
.sc__canvas:focus-visible {
outline: 2px solid rgba(255, 255, 255, .85);
outline-offset: -6px;
}
.sc__status {
position: absolute;
left: $sp-3;
top: $sp-3;
max-width: 62%;
margin: 0;
padding: $sp-1 $sp-3;
border-radius: $r-pill;
background: rgba(255, 255, 255, .85);
color: $subject-ink;
font-weight: 500;
font-size: 11px;
line-height: 1.4;
pointer-events: none;
}
.sc__btn {
position: absolute;
right: $sp-3;
bottom: $sp-3;
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;
}
.sc__btn:focus-visible {
outline: 2px solid #ffffff;
outline-offset: 2px;
}
.sc__caption {
position: absolute;
left: $sp-3;
bottom: $sp-3;
max-width: 68%;
margin: 0;
padding: $sp-1 $sp-3;
border-radius: $r-pill;
background: rgba(255, 255, 255, .85);
color: $subject-ink;
font-weight: 500;
font-size: 12px;
line-height: 1.4;
pointer-events: none;
}
@media (max-width: 340px) {
.sc__caption, .sc__btn { font-size: 10px; padding: $sp-1 $sp-2; }
.sc__status { font-size: 10px; }
}
@media (prefers-reduced-motion: reduce) {
.sc { 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);
}
.sc {
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;
}
.sc__canvas {
display: block;
width: 100%;
height: 100%;
touch-action: none;
}
.sc__canvas:focus-visible {
outline: 2px solid rgba(255, 255, 255, 0.85);
outline-offset: -6px;
}
.sc__status {
position: absolute;
left: 12px;
top: 12px;
max-width: 62%;
margin: 0;
padding: 4px 12px;
border-radius: 999px;
background: rgba(255, 255, 255, 0.85);
color: #17141a;
font-weight: 500;
font-size: 11px;
line-height: 1.4;
pointer-events: none;
}
.sc__btn {
position: absolute;
right: 12px;
bottom: 12px;
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;
}
.sc__btn:focus-visible {
outline: 2px solid #ffffff;
outline-offset: 2px;
}
.sc__caption {
position: absolute;
left: 12px;
bottom: 12px;
max-width: 68%;
margin: 0;
padding: 4px 12px;
border-radius: 999px;
background: rgba(255, 255, 255, 0.85);
color: #17141a;
font-weight: 500;
font-size: 12px;
line-height: 1.4;
pointer-events: none;
}
@media (max-width: 340px) {
.sc__caption, .sc__btn {
font-size: 10px;
padding: 4px 8px;
}
.sc__status {
font-size: 10px;
}
}
@media (prefers-reduced-motion: reduce) {
.sc {
cursor: default;
}
}(function () {
const W = 480;
const H = 300;
const PI2 = Math.PI * 2;
const FIXED_DT = 16;
const REDUCE_STEP_MS = 900;
const REDUCE_START_MS = 1200;
const KEY_STEP = 12;
const FONT = '-apple-system, "Segoe UI", "Noto Sans KR", sans-serif';
const SIG_GREEN = 0;
const SIG_YELLOW = 1;
const SIG_RED = 2;
const GREEN_RGB = [61, 214, 140];
const YELLOW_RGB = [255, 200, 64];
const RED_RGB = [255, 92, 102];
const SIGNAL_RGBS = [GREEN_RGB, YELLOW_RGB, RED_RGB];
const SKY_RGB = [226, 238, 252];
const GRASS_RGB = [206, 236, 214];
const ROAD_RGB = [188, 192, 212];
const ROAD_EDGE_RGB = [162, 166, 192];
const MARK_RGB = [250, 250, 255];
const INK_RGB = [58, 52, 84];
const CAR_RGBS = [[255, 184, 196], [170, 208, 255], [196, 176, 255], [158, 232, 200], [255, 222, 150], [255, 196, 224]];
const TXT_GO = 'Green — go';
const TXT_READY = 'Yellow — get ready to stop';
const TXT_STOP = 'Red — stop';
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]) + ',' + a.toFixed(3) + ')';
}
// 시드 고정 난수 — 같은 시드면 언제나 같은 수열
function mulberry32(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 점의 값 — 정수 두 개를 섞어 0..1 로 (같은 입력은 언제나 같은 값)
function hash2(ix, iy) {
let h = Math.imul(ix | 0, 374761393) + Math.imul(iy | 0, 668265263);
h = Math.imul(h ^ (h >>> 13), 1274126177);
return ((h ^ (h >>> 16)) >>> 0) / 4294967296;
}
// 2차원 값 잡음 — 네 격자 점을 부드럽게 보간
function vnoise(x, y) {
const ix = Math.floor(x);
const iy = Math.floor(y);
const fx = smooth(x - ix);
const fy = smooth(y - iy);
return lerp(lerp(hash2(ix, iy), hash2(ix + 1, iy), fx), lerp(hash2(ix, iy + 1), hash2(ix + 1, iy + 1), fx), fy);
}
function glow(ctx, x, y, r, c, a) {
const g = ctx.createRadialGradient(x, y, 0, x, y, r);
g.addColorStop(0, rgba(c, a));
g.addColorStop(1, rgba(c, 0));
ctx.fillStyle = g;
ctx.fillRect(x - r, y - r, r * 2, r * 2);
}
function rrect(ctx, x, y, w, h, r) {
const rr = Math.min(r, w / 2, h / 2);
ctx.beginPath();
ctx.moveTo(x + rr, y);
ctx.arcTo(x + w, y, x + w, y + h, rr);
ctx.arcTo(x + w, y + h, x, y + h, rr);
ctx.arcTo(x, y + h, x, y, rr);
ctx.arcTo(x, y, x + w, y, rr);
ctx.closePath();
}
// 주기 [초록, 노랑, 빨강] 프레임 수에서 프레임 f 의 신호 상태
function phaseAt(f, g, y, r) {
const total = g + y + r;
const m = ((f % total) + total) % total;
return m < g ? SIG_GREEN : (m < g + y ? SIG_YELLOW : SIG_RED);
}
function stateText(state) {
return state === SIG_GREEN ? TXT_GO : (state === SIG_YELLOW ? TXT_READY : TXT_STOP);
}
// 신호 상태 -> 빨강·노랑·초록 렌즈 밝기 (위에서 아래)
function litOf(state) {
return [state === SIG_RED ? 1 : 0, state === SIG_YELLOW ? 1 : 0, state === SIG_GREEN ? 1 : 0];
}
const LENS_RGBS = [RED_RGB, YELLOW_RGB, GREEN_RGB];
// 세로 신호등 머리 — 렌즈 세 개와 켜진 렌즈의 빛 번짐
function drawHead(ctx, cx, cy, r, lit) {
const step = r * 2.5;
rrect(ctx, cx - r * 1.45, cy - step - r * 1.45, r * 2.9, step * 2 + r * 2.9, r * 0.9);
ctx.fillStyle = rgba(INK_RGB, 1);
ctx.fill();
for (let i = 0; i < 3; i += 1) {
const ly = cy + (i - 1) * step;
ctx.beginPath();
ctx.arc(cx, ly, r, 0, PI2);
ctx.fillStyle = rgba(LENS_RGBS[i], 0.2 + 0.8 * lit[i]);
ctx.fill();
if (lit[i] > 0.02) {
glow(ctx, cx, ly, r * 3.2, LENS_RGBS[i], 0.55 * lit[i]);
}
}
}
// 위에서 본 차 — 앞 범퍼가 x, 가운데가 y. 제동 중이면 뒷등이 켜진다
function drawCar(ctx, x, y, len, wid, rgb, braking) {
const x0 = x - len;
rrect(ctx, x0, y - wid / 2, len, wid, 6);
ctx.fillStyle = rgba(rgb, 1);
ctx.fill();
rrect(ctx, x - len * 0.62, y - wid / 2 + 3, len * 0.34, wid - 6, 3);
ctx.fillStyle = 'rgba(255,255,255,0.62)';
ctx.fill();
ctx.fillStyle = 'rgba(255,248,214,1)';
ctx.fillRect(x - 3, y - wid / 2 + 2, 3, 4);
ctx.fillRect(x - 3, y + wid / 2 - 6, 3, 4);
ctx.fillStyle = braking ? rgba(RED_RGB, 1) : 'rgba(150,120,150,0.8)';
ctx.fillRect(x0, y - wid / 2 + 2, 3, 4);
ctx.fillRect(x0, y + wid / 2 - 6, 3, 4);
if (braking) {
glow(ctx, x0, y, 12, RED_RGB, 0.45);
}
}
// 한 줄 도로 장면의 바탕 — 잔디 위에 도로띠 하나, 정지선과 횡단보도
function drawLaneBackdrop(ctx, roadY, roadH, stopX, seedTrees) {
ctx.fillStyle = rgba(GRASS_RGB, 1);
ctx.fillRect(0, 0, W, H);
const rnd = mulberry32(seedTrees);
for (let i = 0; i < 14; i += 1) {
const tx = 16 + rnd() * (W - 32);
const up = rnd() < 0.5;
const ty = up ? roadY - roadH / 2 - 22 - rnd() * 26 : roadY + roadH / 2 + 22 + rnd() * 26;
ctx.beginPath();
ctx.arc(tx, ty, 9 + rnd() * 6, 0, PI2);
ctx.fillStyle = 'rgba(160,214,184,0.9)';
ctx.fill();
}
ctx.fillStyle = rgba(ROAD_RGB, 1);
ctx.fillRect(0, roadY - roadH / 2, W, roadH);
ctx.fillStyle = rgba(ROAD_EDGE_RGB, 1);
ctx.fillRect(0, roadY - roadH / 2, W, 2);
ctx.fillRect(0, roadY + roadH / 2 - 2, W, 2);
ctx.fillStyle = rgba(MARK_RGB, 0.8);
for (let x = 6; x < W; x += 36) {
ctx.fillRect(x, roadY - 1, 18, 2);
}
for (let k = 0; k < 5; k += 1) {
ctx.fillRect(stopX + 5, roadY - roadH / 2 + 3 + k * (roadH - 6) / 5, 12, (roadH - 6) / 5 - 3);
}
ctx.fillRect(stopX - 2, roadY - roadH / 2, 3, roadH);
}
// 한 줄 차량 흐름 — 앞차 간격(IDM)과 정지선을 같은 식으로 다룬다. 차는 앞쪽부터 0번이다
class Lane {
constructor(seed, p) {
this.cars = [];
this.nextAt = 0;
this.made = 0;
this.p = p;
this.rnd = mulberry32(seed);
}
accelFor(v, s, vL, g0) {
const p = this.p;
const sStar = g0 + Math.max(0, v * p.headway + v * (v - vL) / (2 * Math.sqrt(p.accel * p.brake)));
return p.accel * (1 - Math.pow(v / p.vmax, p.delta) - Math.pow(sStar / Math.max(s, 0.5), 2));
}
// f 프레임에, 뒤쪽이 비어 있고 때가 됐으면 한 대 들여보낸다
maybeSpawn(f, minGap, maxGap, v0) {
if (f < this.nextAt) {
return false;
}
const last = this.cars.length > 0 ? this.cars[this.cars.length - 1] : null;
if (last && last.x - last.len < this.p.gap + 10) {
return false;
}
const rgb = CAR_RGBS[this.made % CAR_RGBS.length];
this.cars.push({ x: -2, v: v0, len: this.p.len, rgb: rgb, go: false, decided: false, sigK: -1, brake: false, id: this.made });
this.made += 1;
this.nextAt = f + minGap + Math.floor(this.rnd() * (maxGap - minGap + 1));
return true;
}
// 신호 목록은 x 오름차순. 한 번 호출 = 한 프레임. 정지선을 넘은 차(detect 용) id 를 돌려준다
step(sigs, onCross, watchX) {
const p = this.p;
for (let i = 0; i < this.cars.length; i += 1) {
const c = this.cars[i];
let acc = this.accelFor(c.v, 1e6, c.v, p.gap);
if (i > 0) {
const L = this.cars[i - 1];
acc = Math.min(acc, this.accelFor(c.v, (L.x - L.len) - c.x, L.v, p.gap));
}
let k = -1;
for (let j = 0; j < sigs.length; j += 1) {
if (sigs[j].x >= c.x) {
k = j;
break;
}
}
let clampX = 1e9;
if (k >= 0) {
const sg = sigs[k];
if (c.sigK !== k) {
c.sigK = k;
c.decided = false;
c.go = false;
}
if (sg.state === SIG_GREEN) {
c.decided = false;
c.go = false;
}
else {
if (!c.decided) {
c.decided = true;
c.go = c.v * c.v / (2 * p.brake) > sg.x - c.x;
}
if (!c.go) {
acc = Math.min(acc, this.accelFor(c.v, sg.x - c.x - 2, 0, p.lineGap));
clampX = sg.x - 1.5;
}
}
}
acc = Math.max(acc, -p.brake * 3);
const prevX = c.x;
c.v = Math.max(0, c.v + acc);
c.x += c.v;
if (c.x > clampX && prevX <= clampX) {
c.x = clampX;
c.v = 0;
}
c.brake = acc < -0.012 || c.v < 0.05;
if (prevX < watchX && c.x >= watchX) {
onCross(c, watchX);
}
}
while (this.cars.length > 0 && this.cars[0].x - this.cars[0].len > W + 20) {
this.cars.shift();
}
}
// 정지선 뒤에서 서 있는 차 수
waiting(stopX) {
let n = 0;
for (let i = 0; i < this.cars.length; i += 1) {
const c = this.cars[i];
if (c.v < 0.25 && c.x < stopX + 2 && c.x > stopX - 260) {
n += 1;
}
}
return n;
}
}
function main(rootEl, canvas, statusEl, btnEl) {
const ctx0 = canvas.getContext('2d');
if (!ctx0) {
return function () { return; };
}
canvas.width = W;
canvas.height = H;
const reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
const scene = makeScene(ctx0, reduce);
if (reduce) {
rootEl.classList.remove('is-demo');
}
let paused = false;
let rafId = 0;
let lastTs = null;
let accMs = 0;
let lastLabel = '';
let px = W / 2;
let py = H / 2;
const cleaners = [];
function listen(target, type, fn) {
target.addEventListener(type, fn);
cleaners.push(function () { target.removeEventListener(type, fn); });
}
function show() {
scene.draw();
const t = scene.label();
if (t !== lastLabel) {
lastLabel = t;
statusEl.textContent = t;
}
}
function advance(ms) {
const n = Math.round(ms / FIXED_DT);
for (let i = 0; i < n; i += 1) {
scene.step();
}
}
function setButton() {
btnEl.textContent = reduce ? 'Next scene' : (paused ? 'Play' : 'Pause');
}
function toLocal(e) {
const r = canvas.getBoundingClientRect();
return [clamp((e.clientX - r.left) * W / r.width, 0, W), clamp((e.clientY - r.top) * H / r.height, 0, H)];
}
function moved() {
if (scene.point) {
scene.point(px, py);
}
if (reduce) {
show();
}
}
function onButton() {
if (reduce) {
advance(REDUCE_STEP_MS);
show();
return;
}
paused = !paused;
if (paused) {
rootEl.classList.remove('is-demo');
}
else {
rootEl.classList.add('is-demo');
}
setButton();
}
function onAction() {
if (scene.tap) {
scene.tap();
if (reduce) {
show();
}
return;
}
onButton();
}
function tick(ts) {
if (lastTs === null) {
lastTs = ts;
}
const frameDt = Math.min(ts - lastTs, 160);
lastTs = ts;
if (!paused) {
accMs += frameDt;
while (accMs >= FIXED_DT) {
scene.step();
accMs -= FIXED_DT;
}
show();
}
rafId = requestAnimationFrame(tick);
}
listen(btnEl, 'click', function () { onButton(); });
listen(canvas, 'pointerdown', function (e) {
const p = toLocal(e);
px = p[0];
py = p[1];
moved();
if (scene.tap) {
scene.tap();
if (reduce) {
show();
}
}
});
listen(canvas, 'pointermove', function (e) {
const p = toLocal(e);
px = p[0];
py = p[1];
moved();
});
listen(canvas, 'keydown', function (e) {
const k = e.key;
if (k === 'Enter' || k === ' ') {
e.preventDefault();
onAction();
return;
}
let dx = 0;
let dy = 0;
if (k === 'ArrowLeft') {
dx = -KEY_STEP;
}
else if (k === 'ArrowRight') {
dx = KEY_STEP;
}
else if (k === 'ArrowUp') {
dy = -KEY_STEP;
}
else if (k === 'ArrowDown') {
dy = KEY_STEP;
}
else {
return;
}
e.preventDefault();
px = clamp(px + dx, 0, W);
py = clamp(py + dy, 0, H);
moved();
});
advance(REDUCE_START_MS);
setButton();
show();
if (!reduce) {
rafId = requestAnimationFrame(tick);
}
function destroy() {
cancelAnimationFrame(rafId);
for (let i = 0; i < cleaners.length; i += 1) {
cleaners[i]();
}
}
return destroy;
}
const GAP_THRESHOLD = 60;
const EXTEND_STEP = 50;
const MAX_GREEN = 300;
const MIN_GREEN = 90;
const DETECTOR_X = 330;
const STOP_LINE_X = 372;
const YELLOW_LEN = 24;
const RED_LEN = 120;
const ROAD_Y = 100;
const ROAD_H = 72;
const CAR_LEN = 40;
const CAR_WID = 26;
const BAR_X = 40;
const BAR_W = 400;
const BAR_Y = 206;
const DENSE_FRAMES = 520;
const SEED = 446;
function makeScene(ctx, reduce) {
const lane = new Lane(SEED, { accel: 0.06, brake: 0.08, gap: 10, lineGap: 3, vmax: 2.1, headway: 8, delta: 4, len: CAR_LEN });
const sig = { x: STOP_LINE_X, state: SIG_RED };
const sigs = [sig];
let f = 0;
let phaseF = RED_LEN - 40;
let greenElapsed = 0;
let budget = MIN_GREEN;
let gapTimer = 0;
let ended = '';
const pips = [];
let detLit = 0;
function onDetect(c, x) {
detLit = 8;
if (sig.state !== SIG_GREEN) {
return;
}
if (gapTimer < GAP_THRESHOLD) {
budget = Math.min(MAX_GREEN, Math.max(budget, greenElapsed + EXTEND_STEP));
pips.push(greenElapsed);
}
gapTimer = 0;
}
function startGreen() {
sig.state = SIG_GREEN;
phaseF = 0;
greenElapsed = 0;
budget = MIN_GREEN;
gapTimer = 0;
pips.length = 0;
ended = '';
}
const scene = {
step: function () {
f += 1;
phaseF += 1;
if (detLit > 0) {
detLit -= 1;
}
const dense = (Math.floor(f / DENSE_FRAMES) % 2) === 0;
if (dense) {
lane.maybeSpawn(f, 30, 46, 2);
}
else {
lane.maybeSpawn(f, 110, 180, 2);
}
if (sig.state === SIG_GREEN) {
greenElapsed += 1;
gapTimer += 1;
if (greenElapsed >= MIN_GREEN && gapTimer >= GAP_THRESHOLD && greenElapsed < budget) {
budget = greenElapsed;
ended = 'gap';
}
if (greenElapsed >= MAX_GREEN) {
budget = greenElapsed;
ended = 'max';
}
if (greenElapsed >= budget) {
sig.state = SIG_YELLOW;
phaseF = 0;
if (ended === '') {
ended = 'gap';
}
}
}
else if (sig.state === SIG_YELLOW) {
if (phaseF >= YELLOW_LEN) {
sig.state = SIG_RED;
phaseF = 0;
}
}
else if (phaseF >= RED_LEN) {
startGreen();
}
lane.step(sigs, onDetect, DETECTOR_X);
},
// 누르면 감지선 바로 위로 차 한 대가 들어온다
tap: function () {
const last = lane.cars.length > 0 ? lane.cars[lane.cars.length - 1] : null;
if (!last || last.x - last.len > 16) {
lane.nextAt = 0;
lane.maybeSpawn(f, 30, 40, 2);
}
},
label: function () {
if (sig.state === SIG_GREEN) {
return 'Green extending — cars keep coming';
}
if (sig.state === SIG_YELLOW) {
return ended === 'max' ? 'Yellow — reached the cap' : 'Yellow — cars stopped coming, green withdrawn';
}
return TXT_STOP;
},
draw: function () {
drawLaneBackdrop(ctx, ROAD_Y, ROAD_H, STOP_LINE_X, 99);
// 정지선 앞 차로 색칠 — 신호 상태가 도로 전체에 번진다
ctx.fillStyle = rgba(SIGNAL_RGBS[sig.state], sig.state === SIG_RED ? 0.1 : 0.17);
ctx.fillRect(0, ROAD_Y - ROAD_H / 2, STOP_LINE_X, ROAD_H);
// 감지선 — 차가 지나는 순간 켜진다
rrect(ctx, DETECTOR_X - 12, ROAD_Y - ROAD_H / 2 + 6, 24, ROAD_H - 12, 4);
ctx.fillStyle = detLit > 0 ? rgba(YELLOW_RGB, 0.9) : 'rgba(255,255,255,0.45)';
ctx.fill();
ctx.lineWidth = 2;
ctx.strokeStyle = rgba(INK_RGB, 0.7);
ctx.stroke();
for (let i = 0; i < lane.cars.length; i += 1) {
const c = lane.cars[i];
drawCar(ctx, c.x, ROAD_Y, c.len, CAR_WID, c.rgb, c.brake);
}
drawHead(ctx, STOP_LINE_X + 20, ROAD_Y - ROAD_H / 2 - 36, 7, litOf(sig.state));
ctx.fillStyle = rgba(INK_RGB, 1);
ctx.fillRect(STOP_LINE_X + 18, ROAD_Y - ROAD_H / 2 - 6, 4, 6);
// 초록 예산 막대 — 흐른 시간 · 늘어난 한도 · 늘릴 때마다 찍힌 점 · 상한
rrect(ctx, BAR_X, BAR_Y, BAR_W, 16, 6);
ctx.fillStyle = 'rgba(255,255,255,0.8)';
ctx.fill();
const inGreen = sig.state === SIG_GREEN;
const limitW = BAR_W * (inGreen ? budget : (sig.state === SIG_YELLOW ? greenElapsed : 0)) / MAX_GREEN;
ctx.fillStyle = rgba(GREEN_RGB, 0.28);
rrect(ctx, BAR_X, BAR_Y, Math.max(limitW, 0), 16, 6);
ctx.fill();
const doneW = BAR_W * (inGreen || sig.state === SIG_YELLOW ? greenElapsed : 0) / MAX_GREEN;
ctx.fillStyle = rgba(GREEN_RGB, 1);
rrect(ctx, BAR_X, BAR_Y, Math.max(doneW, 0), 16, 6);
ctx.fill();
for (let i = 0; i < pips.length; i += 1) {
const px = BAR_X + BAR_W * pips[i] / MAX_GREEN;
ctx.beginPath();
ctx.moveTo(px, BAR_Y - 8);
ctx.lineTo(px + 4, BAR_Y - 3);
ctx.lineTo(px, BAR_Y + 2);
ctx.lineTo(px - 4, BAR_Y - 3);
ctx.closePath();
ctx.fillStyle = rgba(INK_RGB, 1);
ctx.fill();
}
ctx.fillStyle = rgba(RED_RGB, 1);
ctx.fillRect(BAR_X + BAR_W - 3, BAR_Y - 4, 3, 24);
ctx.fillStyle = rgba(INK_RGB, 0.55);
ctx.fillRect(BAR_X + BAR_W * MIN_GREEN / MAX_GREEN - 1, BAR_Y - 2, 2, 20);
// 차 사이 간격 시계 — 기준에 닿으면 초록을 거둔다
const gw = BAR_W * 0.5;
rrect(ctx, BAR_X, BAR_Y + 30, gw, 10, 4);
ctx.fillStyle = 'rgba(255,255,255,0.8)';
ctx.fill();
const gf = inGreen ? clamp(gapTimer / GAP_THRESHOLD, 0, 1) : 0;
ctx.fillStyle = rgba(gf > 0.8 ? RED_RGB : YELLOW_RGB, 1);
rrect(ctx, BAR_X, BAR_Y + 30, Math.max(gw * gf, 0), 10, 4);
ctx.fill();
}
};
for (let i = 0; i < 300; i += 1) {
scene.step();
}
void reduce;
return scene;
}
main(document.getElementById('scRoot'), document.getElementById('scCanvas'), document.getElementById('scStatus'), document.getElementById('scBtn'));
})();import { useEffect, useRef } from "react";
import styles from "./TlGapOutGreenExtension.module.scss";
const W = 480;
const H = 300;
const PI2 = Math.PI * 2;
const FIXED_DT = 16;
const REDUCE_STEP_MS = 900;
const REDUCE_START_MS = 1200;
const KEY_STEP = 12;
const FONT = '-apple-system, "Segoe UI", "Noto Sans KR", sans-serif';
const SIG_GREEN = 0;
const SIG_YELLOW = 1;
const SIG_RED = 2;
const GREEN_RGB = [61, 214, 140];
const YELLOW_RGB = [255, 200, 64];
const RED_RGB = [255, 92, 102];
const SIGNAL_RGBS = [GREEN_RGB, YELLOW_RGB, RED_RGB];
const SKY_RGB = [226, 238, 252];
const GRASS_RGB = [206, 236, 214];
const ROAD_RGB = [188, 192, 212];
const ROAD_EDGE_RGB = [162, 166, 192];
const MARK_RGB = [250, 250, 255];
const INK_RGB = [58, 52, 84];
const CAR_RGBS = [[255, 184, 196], [170, 208, 255], [196, 176, 255], [158, 232, 200], [255, 222, 150], [255, 196, 224]];
const TXT_GO = '초록불 — 진행';
const TXT_READY = '노란불 — 정지 준비';
const TXT_STOP = '빨간불 — 정지';
type Pt = [number, number];
interface Scene {
step(): void;
draw(): void;
label(): string;
point?(x: number, y: number): void;
tap?(): void;
}
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: number[], a: number): string {
return 'rgba(' + Math.round(c[0]) + ',' + Math.round(c[1]) + ',' + Math.round(c[2]) + ',' + a.toFixed(3) + ')';
}
// 시드 고정 난수 — 같은 시드면 언제나 같은 수열
function mulberry32(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 점의 값 — 정수 두 개를 섞어 0..1 로 (같은 입력은 언제나 같은 값)
function hash2(ix: number, iy: number): number {
let h = Math.imul(ix | 0, 374761393) + Math.imul(iy | 0, 668265263);
h = Math.imul(h ^ (h >>> 13), 1274126177);
return ((h ^ (h >>> 16)) >>> 0) / 4294967296;
}
// 2차원 값 잡음 — 네 격자 점을 부드럽게 보간
function vnoise(x: number, y: number): number {
const ix = Math.floor(x);
const iy = Math.floor(y);
const fx = smooth(x - ix);
const fy = smooth(y - iy);
return lerp(lerp(hash2(ix, iy), hash2(ix + 1, iy), fx), lerp(hash2(ix, iy + 1), hash2(ix + 1, iy + 1), fx), fy);
}
function glow(ctx: CanvasRenderingContext2D, x: number, y: number, r: number, c: number[], a: number): void {
const g = ctx.createRadialGradient(x, y, 0, x, y, r);
g.addColorStop(0, rgba(c, a));
g.addColorStop(1, rgba(c, 0));
ctx.fillStyle = g;
ctx.fillRect(x - r, y - r, r * 2, r * 2);
}
function rrect(ctx: CanvasRenderingContext2D, x: number, y: number, w: number, h: number, r: number): void {
const rr = Math.min(r, w / 2, h / 2);
ctx.beginPath();
ctx.moveTo(x + rr, y);
ctx.arcTo(x + w, y, x + w, y + h, rr);
ctx.arcTo(x + w, y + h, x, y + h, rr);
ctx.arcTo(x, y + h, x, y, rr);
ctx.arcTo(x, y, x + w, y, rr);
ctx.closePath();
}
// 주기 [초록, 노랑, 빨강] 프레임 수에서 프레임 f 의 신호 상태
function phaseAt(f: number, g: number, y: number, r: number): number {
const total = g + y + r;
const m = ((f % total) + total) % total;
return m < g ? SIG_GREEN : (m < g + y ? SIG_YELLOW : SIG_RED);
}
function stateText(state: number): string {
return state === SIG_GREEN ? TXT_GO : (state === SIG_YELLOW ? TXT_READY : TXT_STOP);
}
// 신호 상태 -> 빨강·노랑·초록 렌즈 밝기 (위에서 아래)
function litOf(state: number): number[] {
return [state === SIG_RED ? 1 : 0, state === SIG_YELLOW ? 1 : 0, state === SIG_GREEN ? 1 : 0];
}
const LENS_RGBS = [RED_RGB, YELLOW_RGB, GREEN_RGB];
// 세로 신호등 머리 — 렌즈 세 개와 켜진 렌즈의 빛 번짐
function drawHead(ctx: CanvasRenderingContext2D, cx: number, cy: number, r: number, lit: number[]): void {
const step = r * 2.5;
rrect(ctx, cx - r * 1.45, cy - step - r * 1.45, r * 2.9, step * 2 + r * 2.9, r * 0.9);
ctx.fillStyle = rgba(INK_RGB, 1);
ctx.fill();
for (let i = 0; i < 3; i += 1) {
const ly = cy + (i - 1) * step;
ctx.beginPath();
ctx.arc(cx, ly, r, 0, PI2);
ctx.fillStyle = rgba(LENS_RGBS[i], 0.2 + 0.8 * lit[i]);
ctx.fill();
if (lit[i] > 0.02) {
glow(ctx, cx, ly, r * 3.2, LENS_RGBS[i], 0.55 * lit[i]);
}
}
}
// 위에서 본 차 — 앞 범퍼가 x, 가운데가 y. 제동 중이면 뒷등이 켜진다
function drawCar(ctx: CanvasRenderingContext2D, x: number, y: number, len: number, wid: number, rgb: number[], braking: boolean): void {
const x0 = x - len;
rrect(ctx, x0, y - wid / 2, len, wid, 6);
ctx.fillStyle = rgba(rgb, 1);
ctx.fill();
rrect(ctx, x - len * 0.62, y - wid / 2 + 3, len * 0.34, wid - 6, 3);
ctx.fillStyle = 'rgba(255,255,255,0.62)';
ctx.fill();
ctx.fillStyle = 'rgba(255,248,214,1)';
ctx.fillRect(x - 3, y - wid / 2 + 2, 3, 4);
ctx.fillRect(x - 3, y + wid / 2 - 6, 3, 4);
ctx.fillStyle = braking ? rgba(RED_RGB, 1) : 'rgba(150,120,150,0.8)';
ctx.fillRect(x0, y - wid / 2 + 2, 3, 4);
ctx.fillRect(x0, y + wid / 2 - 6, 3, 4);
if (braking) {
glow(ctx, x0, y, 12, RED_RGB, 0.45);
}
}
// 한 줄 도로 장면의 바탕 — 잔디 위에 도로띠 하나, 정지선과 횡단보도
function drawLaneBackdrop(ctx: CanvasRenderingContext2D, roadY: number, roadH: number, stopX: number, seedTrees: number): void {
ctx.fillStyle = rgba(GRASS_RGB, 1);
ctx.fillRect(0, 0, W, H);
const rnd = mulberry32(seedTrees);
for (let i = 0; i < 14; i += 1) {
const tx = 16 + rnd() * (W - 32);
const up = rnd() < 0.5;
const ty = up ? roadY - roadH / 2 - 22 - rnd() * 26 : roadY + roadH / 2 + 22 + rnd() * 26;
ctx.beginPath();
ctx.arc(tx, ty, 9 + rnd() * 6, 0, PI2);
ctx.fillStyle = 'rgba(160,214,184,0.9)';
ctx.fill();
}
ctx.fillStyle = rgba(ROAD_RGB, 1);
ctx.fillRect(0, roadY - roadH / 2, W, roadH);
ctx.fillStyle = rgba(ROAD_EDGE_RGB, 1);
ctx.fillRect(0, roadY - roadH / 2, W, 2);
ctx.fillRect(0, roadY + roadH / 2 - 2, W, 2);
ctx.fillStyle = rgba(MARK_RGB, 0.8);
for (let x = 6; x < W; x += 36) {
ctx.fillRect(x, roadY - 1, 18, 2);
}
for (let k = 0; k < 5; k += 1) {
ctx.fillRect(stopX + 5, roadY - roadH / 2 + 3 + k * (roadH - 6) / 5, 12, (roadH - 6) / 5 - 3);
}
ctx.fillRect(stopX - 2, roadY - roadH / 2, 3, roadH);
}
interface Car { x: number; v: number; len: number; rgb: number[]; go: boolean; decided: boolean; sigK: number; brake: boolean; id: number; }
interface Sig { x: number; state: number; }
interface LaneParams { accel: number; brake: number; gap: number; lineGap: number; vmax: number; headway: number; delta: number; len: number; }
// 한 줄 차량 흐름 — 앞차 간격(IDM)과 정지선을 같은 식으로 다룬다. 차는 앞쪽부터 0번이다
class Lane {
cars: Car[] = [];
p: LaneParams;
rnd: () => number;
nextAt = 0;
made = 0;
constructor(seed: number, p: LaneParams) {
this.p = p;
this.rnd = mulberry32(seed);
}
accelFor(v: number, s: number, vL: number, g0: number): number {
const p = this.p;
const sStar = g0 + Math.max(0, v * p.headway + v * (v - vL) / (2 * Math.sqrt(p.accel * p.brake)));
return p.accel * (1 - Math.pow(v / p.vmax, p.delta) - Math.pow(sStar / Math.max(s, 0.5), 2));
}
// f 프레임에, 뒤쪽이 비어 있고 때가 됐으면 한 대 들여보낸다
maybeSpawn(f: number, minGap: number, maxGap: number, v0: number): boolean {
if (f < this.nextAt) { return false; }
const last = this.cars.length > 0 ? this.cars[this.cars.length - 1] : null;
if (last && last.x - last.len < this.p.gap + 10) { return false; }
const rgb = CAR_RGBS[this.made % CAR_RGBS.length];
this.cars.push({ x: -2, v: v0, len: this.p.len, rgb: rgb, go: false, decided: false, sigK: -1, brake: false, id: this.made });
this.made += 1;
this.nextAt = f + minGap + Math.floor(this.rnd() * (maxGap - minGap + 1));
return true;
}
// 신호 목록은 x 오름차순. 한 번 호출 = 한 프레임. 정지선을 넘은 차(detect 용) id 를 돌려준다
step(sigs: Sig[], onCross: (c: Car, x: number) => void, watchX: number): void {
const p = this.p;
for (let i = 0; i < this.cars.length; i += 1) {
const c = this.cars[i];
let acc = this.accelFor(c.v, 1e6, c.v, p.gap);
if (i > 0) {
const L = this.cars[i - 1];
acc = Math.min(acc, this.accelFor(c.v, (L.x - L.len) - c.x, L.v, p.gap));
}
let k = -1;
for (let j = 0; j < sigs.length; j += 1) {
if (sigs[j].x >= c.x) { k = j; break; }
}
let clampX = 1e9;
if (k >= 0) {
const sg = sigs[k];
if (c.sigK !== k) { c.sigK = k; c.decided = false; c.go = false; }
if (sg.state === SIG_GREEN) {
c.decided = false;
c.go = false;
} else {
if (!c.decided) {
c.decided = true;
c.go = c.v * c.v / (2 * p.brake) > sg.x - c.x;
}
if (!c.go) {
acc = Math.min(acc, this.accelFor(c.v, sg.x - c.x - 2, 0, p.lineGap));
clampX = sg.x - 1.5;
}
}
}
acc = Math.max(acc, -p.brake * 3);
const prevX = c.x;
c.v = Math.max(0, c.v + acc);
c.x += c.v;
if (c.x > clampX && prevX <= clampX) {
c.x = clampX;
c.v = 0;
}
c.brake = acc < -0.012 || c.v < 0.05;
if (prevX < watchX && c.x >= watchX) { onCross(c, watchX); }
}
while (this.cars.length > 0 && this.cars[0].x - this.cars[0].len > W + 20) {
this.cars.shift();
}
}
// 정지선 뒤에서 서 있는 차 수
waiting(stopX: number): number {
let n = 0;
for (let i = 0; i < this.cars.length; i += 1) {
const c = this.cars[i];
if (c.v < 0.25 && c.x < stopX + 2 && c.x > stopX - 260) { n += 1; }
}
return n;
}
}
function main(rootEl: HTMLElement, canvas: HTMLCanvasElement, statusEl: HTMLElement, btnEl: HTMLButtonElement): () => void {
const ctx0 = canvas.getContext('2d');
if (!ctx0) { return function (): void { return; }; }
canvas.width = W;
canvas.height = H;
const reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
const scene = makeScene(ctx0, reduce);
if (reduce) { rootEl.classList.remove('is-demo'); }
let paused = false;
let rafId = 0;
let lastTs: number | null = null;
let accMs = 0;
let lastLabel = '';
let px = W / 2;
let py = H / 2;
const cleaners: Array<() => void> = [];
function listen(target: EventTarget, type: string, fn: (e: Event) => void): void {
target.addEventListener(type, fn);
cleaners.push(function (): void { target.removeEventListener(type, fn); });
}
function show(): void {
scene.draw();
const t = scene.label();
if (t !== lastLabel) {
lastLabel = t;
statusEl.textContent = t;
}
}
function advance(ms: number): void {
const n = Math.round(ms / FIXED_DT);
for (let i = 0; i < n; i += 1) { scene.step(); }
}
function setButton(): void {
btnEl.textContent = reduce ? '다음 장면' : (paused ? '재생' : '멈춤');
}
function toLocal(e: PointerEvent): Pt {
const r = canvas.getBoundingClientRect();
return [clamp((e.clientX - r.left) * W / r.width, 0, W), clamp((e.clientY - r.top) * H / r.height, 0, H)];
}
function moved(): void {
if (scene.point) { scene.point(px, py); }
if (reduce) { show(); }
}
function onButton(): void {
if (reduce) {
advance(REDUCE_STEP_MS);
show();
return;
}
paused = !paused;
if (paused) { rootEl.classList.remove('is-demo'); } else { rootEl.classList.add('is-demo'); }
setButton();
}
function onAction(): void {
if (scene.tap) {
scene.tap();
if (reduce) { show(); }
return;
}
onButton();
}
function tick(ts: number): void {
if (lastTs === null) { lastTs = ts; }
const frameDt = Math.min(ts - lastTs, 160);
lastTs = ts;
if (!paused) {
accMs += frameDt;
while (accMs >= FIXED_DT) {
scene.step();
accMs -= FIXED_DT;
}
show();
}
rafId = requestAnimationFrame(tick);
}
listen(btnEl, 'click', function (): void { onButton(); });
listen(canvas, 'pointerdown', function (e: Event): void {
const p = toLocal(e as PointerEvent);
px = p[0];
py = p[1];
moved();
if (scene.tap) {
scene.tap();
if (reduce) { show(); }
}
});
listen(canvas, 'pointermove', function (e: Event): void {
const p = toLocal(e as PointerEvent);
px = p[0];
py = p[1];
moved();
});
listen(canvas, 'keydown', function (e: Event): void {
const k = (e as KeyboardEvent).key;
if (k === 'Enter' || k === ' ') {
e.preventDefault();
onAction();
return;
}
let dx = 0;
let dy = 0;
if (k === 'ArrowLeft') { dx = -KEY_STEP; } else if (k === 'ArrowRight') { dx = KEY_STEP; }
else if (k === 'ArrowUp') { dy = -KEY_STEP; } else if (k === 'ArrowDown') { dy = KEY_STEP; }
else { return; }
e.preventDefault();
px = clamp(px + dx, 0, W);
py = clamp(py + dy, 0, H);
moved();
});
advance(REDUCE_START_MS);
setButton();
show();
if (!reduce) {
rafId = requestAnimationFrame(tick);
}
function destroy(): void {
cancelAnimationFrame(rafId);
for (let i = 0; i < cleaners.length; i += 1) { cleaners[i](); }
}
return destroy;
}
const GAP_THRESHOLD = 60;
const EXTEND_STEP = 50;
const MAX_GREEN = 300;
const MIN_GREEN = 90;
const DETECTOR_X = 330;
const STOP_LINE_X = 372;
const YELLOW_LEN = 24;
const RED_LEN = 120;
const ROAD_Y = 100;
const ROAD_H = 72;
const CAR_LEN = 40;
const CAR_WID = 26;
const BAR_X = 40;
const BAR_W = 400;
const BAR_Y = 206;
const DENSE_FRAMES = 520;
const SEED = 446;
function makeScene(ctx: CanvasRenderingContext2D, reduce: boolean): Scene {
const lane = new Lane(SEED, { accel: 0.06, brake: 0.08, gap: 10, lineGap: 3, vmax: 2.1, headway: 8, delta: 4, len: CAR_LEN });
const sig: Sig = { x: STOP_LINE_X, state: SIG_RED };
const sigs: Sig[] = [sig];
let f = 0;
let phaseF = RED_LEN - 40;
let greenElapsed = 0;
let budget = MIN_GREEN;
let gapTimer = 0;
let ended = '';
const pips: number[] = [];
let detLit = 0;
function onDetect(c: Car, x: number): void {
detLit = 8;
if (sig.state !== SIG_GREEN) { return; }
if (gapTimer < GAP_THRESHOLD) {
budget = Math.min(MAX_GREEN, Math.max(budget, greenElapsed + EXTEND_STEP));
pips.push(greenElapsed);
}
gapTimer = 0;
}
function startGreen(): void {
sig.state = SIG_GREEN;
phaseF = 0;
greenElapsed = 0;
budget = MIN_GREEN;
gapTimer = 0;
pips.length = 0;
ended = '';
}
const scene: Scene = {
step: function (): void {
f += 1;
phaseF += 1;
if (detLit > 0) { detLit -= 1; }
const dense = (Math.floor(f / DENSE_FRAMES) % 2) === 0;
if (dense) { lane.maybeSpawn(f, 30, 46, 2); } else { lane.maybeSpawn(f, 110, 180, 2); }
if (sig.state === SIG_GREEN) {
greenElapsed += 1;
gapTimer += 1;
if (greenElapsed >= MIN_GREEN && gapTimer >= GAP_THRESHOLD && greenElapsed < budget) {
budget = greenElapsed;
ended = 'gap';
}
if (greenElapsed >= MAX_GREEN) {
budget = greenElapsed;
ended = 'max';
}
if (greenElapsed >= budget) {
sig.state = SIG_YELLOW;
phaseF = 0;
if (ended === '') { ended = 'gap'; }
}
} else if (sig.state === SIG_YELLOW) {
if (phaseF >= YELLOW_LEN) {
sig.state = SIG_RED;
phaseF = 0;
}
} else if (phaseF >= RED_LEN) {
startGreen();
}
lane.step(sigs, onDetect, DETECTOR_X);
},
// 누르면 감지선 바로 위로 차 한 대가 들어온다
tap: function (): void {
const last = lane.cars.length > 0 ? lane.cars[lane.cars.length - 1] : null;
if (!last || last.x - last.len > 16) {
lane.nextAt = 0;
lane.maybeSpawn(f, 30, 40, 2);
}
},
label: function (): string {
if (sig.state === SIG_GREEN) { return '초록 연장 중 — 차가 이어짐'; }
if (sig.state === SIG_YELLOW) { return ended === 'max' ? '노란불 — 상한에 도달' : '노란불 — 차가 끊겨 초록을 거둠'; }
return TXT_STOP;
},
draw: function (): void {
drawLaneBackdrop(ctx, ROAD_Y, ROAD_H, STOP_LINE_X, 99);
// 정지선 앞 차로 색칠 — 신호 상태가 도로 전체에 번진다
ctx.fillStyle = rgba(SIGNAL_RGBS[sig.state], sig.state === SIG_RED ? 0.1 : 0.17);
ctx.fillRect(0, ROAD_Y - ROAD_H / 2, STOP_LINE_X, ROAD_H);
// 감지선 — 차가 지나는 순간 켜진다
rrect(ctx, DETECTOR_X - 12, ROAD_Y - ROAD_H / 2 + 6, 24, ROAD_H - 12, 4);
ctx.fillStyle = detLit > 0 ? rgba(YELLOW_RGB, 0.9) : 'rgba(255,255,255,0.45)';
ctx.fill();
ctx.lineWidth = 2;
ctx.strokeStyle = rgba(INK_RGB, 0.7);
ctx.stroke();
for (let i = 0; i < lane.cars.length; i += 1) {
const c = lane.cars[i];
drawCar(ctx, c.x, ROAD_Y, c.len, CAR_WID, c.rgb, c.brake);
}
drawHead(ctx, STOP_LINE_X + 20, ROAD_Y - ROAD_H / 2 - 36, 7, litOf(sig.state));
ctx.fillStyle = rgba(INK_RGB, 1);
ctx.fillRect(STOP_LINE_X + 18, ROAD_Y - ROAD_H / 2 - 6, 4, 6);
// 초록 예산 막대 — 흐른 시간 · 늘어난 한도 · 늘릴 때마다 찍힌 점 · 상한
rrect(ctx, BAR_X, BAR_Y, BAR_W, 16, 6);
ctx.fillStyle = 'rgba(255,255,255,0.8)';
ctx.fill();
const inGreen = sig.state === SIG_GREEN;
const limitW = BAR_W * (inGreen ? budget : (sig.state === SIG_YELLOW ? greenElapsed : 0)) / MAX_GREEN;
ctx.fillStyle = rgba(GREEN_RGB, 0.28);
rrect(ctx, BAR_X, BAR_Y, Math.max(limitW, 0), 16, 6);
ctx.fill();
const doneW = BAR_W * (inGreen || sig.state === SIG_YELLOW ? greenElapsed : 0) / MAX_GREEN;
ctx.fillStyle = rgba(GREEN_RGB, 1);
rrect(ctx, BAR_X, BAR_Y, Math.max(doneW, 0), 16, 6);
ctx.fill();
for (let i = 0; i < pips.length; i += 1) {
const px = BAR_X + BAR_W * pips[i] / MAX_GREEN;
ctx.beginPath();
ctx.moveTo(px, BAR_Y - 8);
ctx.lineTo(px + 4, BAR_Y - 3);
ctx.lineTo(px, BAR_Y + 2);
ctx.lineTo(px - 4, BAR_Y - 3);
ctx.closePath();
ctx.fillStyle = rgba(INK_RGB, 1);
ctx.fill();
}
ctx.fillStyle = rgba(RED_RGB, 1);
ctx.fillRect(BAR_X + BAR_W - 3, BAR_Y - 4, 3, 24);
ctx.fillStyle = rgba(INK_RGB, 0.55);
ctx.fillRect(BAR_X + BAR_W * MIN_GREEN / MAX_GREEN - 1, BAR_Y - 2, 2, 20);
// 차 사이 간격 시계 — 기준에 닿으면 초록을 거둔다
const gw = BAR_W * 0.5;
rrect(ctx, BAR_X, BAR_Y + 30, gw, 10, 4);
ctx.fillStyle = 'rgba(255,255,255,0.8)';
ctx.fill();
const gf = inGreen ? clamp(gapTimer / GAP_THRESHOLD, 0, 1) : 0;
ctx.fillStyle = rgba(gf > 0.8 ? RED_RGB : YELLOW_RGB, 1);
rrect(ctx, BAR_X, BAR_Y + 30, Math.max(gw * gf, 0), 10, 4);
ctx.fill();
}
};
for (let i = 0; i < 300; i += 1) { scene.step(); }
void reduce;
return scene;
}
export default function TlGapOutGreenExtension() {
const rootRef = useRef<HTMLDivElement | null>(null);
const canvasRef = useRef<HTMLCanvasElement | null>(null);
const statusRef = useRef<HTMLParagraphElement | null>(null);
const btnRef = useRef<HTMLButtonElement | null>(null);
useEffect(() => {
const root = rootRef.current;
const canvas = canvasRef.current;
const statusEl = statusRef.current;
const btnEl = btnRef.current;
if (!root || !canvas || !statusEl || !btnEl) return;
return main(root, canvas, statusEl, btnEl);
}, []);
return (
<main className={styles.stage}>
<div className={`${styles.sc} is-demo`} ref={rootRef}>
<canvas className={styles.sc__canvas} ref={canvasRef} width={480} height={300} tabIndex={0} aria-label="차가 끊기면 초록을 거두고 이어지면 늘리는 감응 신호" />
<p className={styles.sc__status} ref={statusRef} aria-live="polite">초록불 — 진행</p>
<button className={styles.sc__btn} ref={btnRef} type="button">멈춤</button>
<p className={styles.sc__caption}>차가 끊기면 초록을 거두고 이어지면 늘리는 감응 신호</p>
</div>
</main>
);
}09 A Responsive Signal That Ends Green When Cars Stop Coming and Extends It While They Do — Measured area 10.003% · moving frames 23/23Original by GODRICH · SCSS and React ship in the zip · Traffic Light CSS: 9 Demos With Queues and Waves
The post this demo lives in
Traffic Light CSS: 9 Demos With Queues and WavesA traffic light css built as a color-swapping timer lets cars roll through red, signals drift out of step and pedestrian See all demos in this post
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