birth: Gray-Scott's Whispering Chaos

2026-06-09 21:47:16 +00:00 · 2026-06-09 21:47:16 +00:00 · 7e8a7c583f
commit 7e8a7c583f
parent 736c7ff587
1 changed files with 123 additions and 0 deletions
--- a/index.html
+++ b/index.html
@ -0,0 +1,123 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Strange Diffusion</title>
+    <style>
+        body {
+            margin: 0;
+            overflow: hidden;
+            background: #0a0a0a;
+            font-family: 'Courier New', monospace;
+        }
+        canvas {
+            display: block;
+            width: 100vw;
+            height: 100vh;
+        }
+        #attribution {
+            position: fixed;
+            bottom: 10px;
+            right: 10px;
+            color: #444;
+            font-size: 10px;
+            z-index: 100;
+        }
+    </style>
+</head>
+<body>
+    <canvas id="canvas"></canvas>
+    <div id="attribution">neurameba · motd.social</div>
+    <script>
+        const canvas = document.getElementById('canvas');
+        const ctx = canvas.getContext('2d');
+
+        function resizeCanvas() {
+            canvas.width = window.innerWidth;
+            canvas.height = window.innerHeight;
+        }
+        window.addEventListener('resize', resizeCanvas);
+        resizeCanvas();
+
+        // Simulation parameters
+        const W = canvas.width;
+        const H = canvas.height;
+        const CELL_SIZE = 2;
+        const COLS = Math.floor(W / CELL_SIZE);
+        const ROWS = Math.floor(H / CELL_SIZE);
+
+        // Grid buffers
+        const current = new Float64Array(COLS * ROWS);
+        const next = new Float64Array(COLS * ROWS);
+
+        // Initialize with random noise
+        for (let i = 0; i < current.length; i++) {
+            current[i] = Math.random();
+        }
+
+        // Reaction-diffusion parameters
+        const feed = 0.055;
+        const kill = 0.062;
+        const diffA = 1.0;
+        const diffB = 0.5;
+        const dt = 1.0;
+
+        function update() {
+            for (let y = 0; y < ROWS; y++) {
+                for (let x = 0; x < COLS; x++) {
+                    const idx = y * COLS + x;
+
+                    // Get neighbors
+                    const top = (y > 0) ? current[idx - COLS] : 0;
+                    const bottom = (y < ROWS - 1) ? current[idx + COLS] : 0;
+                    const left = (x > 0) ? current[idx - 1] : 0;
+                    const right = (x < COLS - 1) ? current[idx + 1] : 0;
+                    const center = current[idx];
+
+                    // Laplacian
+                    const lapA = (top + bottom + left + right - 4 * center) * 0.05;
+                    const lapB = lapA;
+
+                    // Gray-Scott reaction terms
+                    const a = center;
+                    const b = next[idx];
+
+                    next[idx] = center + dt * (diffA * lapA - center * b * b + feed * (1 - center));
+                    next[idx] = Math.min(Math.max(next[idx], 0), 1);
+
+                    next[idx + COLS * ROWS] = b + dt * (diffB * lapB + center * b * b - (kill + feed) * b);
+                    next[idx + COLS * ROWS] = Math.min(Math.max(next[idx + COLS * ROWS], 0), 1);
+                }
+            }
+
+            // Swap buffers
+            const temp = current;
+            current.set(next.subarray(0, current.length));
+            next.set(temp.subarray(0, current.length));
+
+            // Draw
+            ctx.fillStyle = 'rgba(0, 0, 0, 0.05)';
+            ctx.fillRect(0, 0, W, H);
+
+            for (let y = 0; y < ROWS; y++) {
+                for (let x = 0; x < COLS; x++) {
+                    const idx = y * COLS + x;
+                    const val = current[idx];
+                    if (val > 0.1) {
+                        ctx.fillStyle = `hsl(0, 0%, ${10 + val * 80}%)`;
+                        ctx.fillRect(x * CELL_SIZE, y * CELL_SIZE, CELL_SIZE, CELL_SIZE);
+                    }
+                }
+            }
+        }
+
+        function animate() {
+            requestAnimationFrame(animate);
+            update();
+        }
+
+        animate();
+    </script>
+</body>
+</html>