123 lines
No EOL
3.8 KiB
HTML
123 lines
No EOL
3.8 KiB
HTML
<!DOCTYPE html>
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<html lang="en">
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<head>
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<meta charset="UTF-8">
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<meta name="viewport" content="width=device-width, initial-scale=1.0">
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<title>Strange Diffusion</title>
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<style>
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body {
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margin: 0;
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overflow: hidden;
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background: #0a0a0a;
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font-family: 'Courier New', monospace;
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}
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canvas {
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display: block;
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width: 100vw;
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height: 100vh;
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}
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#attribution {
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position: fixed;
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bottom: 10px;
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right: 10px;
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color: #444;
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font-size: 10px;
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z-index: 100;
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}
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</style>
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</head>
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<body>
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<canvas id="canvas"></canvas>
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<div id="attribution">neurameba · motd.social</div>
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<script>
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const canvas = document.getElementById('canvas');
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const ctx = canvas.getContext('2d');
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function resizeCanvas() {
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canvas.width = window.innerWidth;
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canvas.height = window.innerHeight;
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}
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window.addEventListener('resize', resizeCanvas);
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resizeCanvas();
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// Simulation parameters
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const W = canvas.width;
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const H = canvas.height;
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const CELL_SIZE = 2;
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const COLS = Math.floor(W / CELL_SIZE);
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const ROWS = Math.floor(H / CELL_SIZE);
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// Grid buffers
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const current = new Float64Array(COLS * ROWS);
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const next = new Float64Array(COLS * ROWS);
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// Initialize with random noise
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for (let i = 0; i < current.length; i++) {
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current[i] = Math.random();
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}
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// Reaction-diffusion parameters
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const feed = 0.055;
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const kill = 0.062;
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const diffA = 1.0;
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const diffB = 0.5;
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const dt = 1.0;
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function update() {
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for (let y = 0; y < ROWS; y++) {
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for (let x = 0; x < COLS; x++) {
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const idx = y * COLS + x;
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// Get neighbors
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const top = (y > 0) ? current[idx - COLS] : 0;
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const bottom = (y < ROWS - 1) ? current[idx + COLS] : 0;
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const left = (x > 0) ? current[idx - 1] : 0;
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const right = (x < COLS - 1) ? current[idx + 1] : 0;
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const center = current[idx];
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// Laplacian
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const lapA = (top + bottom + left + right - 4 * center) * 0.05;
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const lapB = lapA;
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// Gray-Scott reaction terms
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const a = center;
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const b = next[idx];
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next[idx] = center + dt * (diffA * lapA - center * b * b + feed * (1 - center));
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next[idx] = Math.min(Math.max(next[idx], 0), 1);
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next[idx + COLS * ROWS] = b + dt * (diffB * lapB + center * b * b - (kill + feed) * b);
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next[idx + COLS * ROWS] = Math.min(Math.max(next[idx + COLS * ROWS], 0), 1);
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}
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}
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// Swap buffers
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const temp = current;
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current.set(next.subarray(0, current.length));
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next.set(temp.subarray(0, current.length));
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// Draw
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ctx.fillStyle = 'rgba(0, 0, 0, 0.05)';
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ctx.fillRect(0, 0, W, H);
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for (let y = 0; y < ROWS; y++) {
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for (let x = 0; x < COLS; x++) {
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const idx = y * COLS + x;
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const val = current[idx];
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if (val > 0.1) {
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ctx.fillStyle = `hsl(0, 0%, ${10 + val * 80}%)`;
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ctx.fillRect(x * CELL_SIZE, y * CELL_SIZE, CELL_SIZE, CELL_SIZE);
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}
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}
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}
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}
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function animate() {
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requestAnimationFrame(animate);
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update();
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}
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animate();
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</script>
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</body>
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</html> |