birth: gray haze forming pulse

2026-04-05 17:47:16 +00:00 · 2026-04-05 17:47:16 +00:00 · 9f08fd2353
commit 9f08fd2353
parent 31513a95e2
1 changed files with 140 additions and 0 deletions
--- a/index.html
+++ b/index.html
@ -0,0 +1,140 @@
+```html
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Diffusion Fields</title>
+    <style>
+        body { margin: 0; overflow: hidden; background: #0a0a0a; }
+        canvas { display: block; }
+        #attribution { position: absolute; bottom: 10px; left: 10px; color: #666; font-family: monospace; font-size: 10px; }
+    </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 resize() {
+            canvas.width = window.innerWidth;
+            canvas.height = window.innerHeight;
+        }
+        window.addEventListener('resize', resize);
+        resize();
+
+        // Reaction-diffusion system parameters
+        const params = {
+            feedRate: 0.055,
+            killRate: 0.062,
+            diffusionRateA: 1.0,
+            diffusionRateB: 0.5,
+            timeStep: 1.0,
+            gridSize: 3,
+            width: Math.floor(canvas.width / 3),
+            height: Math.floor(canvas.height / 3),
+            palette: [
+                'rgba(230, 230, 230, 0.8)',
+                'rgba(200, 200, 200, 0.8)',
+                'rgba(170, 170, 170, 0.8)',
+                'rgba(140, 140, 140, 0.8)'
+            ]
+        };
+
+        // Initialize grids
+        let gridA = createEmptyGrid();
+        let gridB = createEmptyGrid();
+        let nextGridA = createEmptyGrid();
+        let nextGridB = createEmptyGrid();
+
+        // Initialize with random values
+        function createEmptyGrid() {
+            const grid = new Array(params.width);
+            for (let x = 0; x < params.width; x++) {
+                grid[x] = new Array(params.height);
+                for (let y = 0; y < params.height; y++) {
+                    grid[x][y] = {
+                        a: Math.random() * 0.1 + 0.01,
+                        b: Math.random() * 0.1
+                    };
+                }
+            }
+            return grid;
+        }
+
+        // Compute reaction-diffusion step
+        function step() {
+            for (let x = 1; x < params.width - 1; x++) {
+                for (let y = 1; y < params.height - 1; y++) {
+                    const a = gridA[x][y].a;
+                    const b = gridA[x][y].b;
+
+                    // Reaction
+                    const reaction = a * b * b;
+                    const deltaA = params.diffusionRateA * laplaceA(x, y) - reaction;
+                    const deltaB = params.diffusionRateB * laplaceB(x, y) + reaction;
+
+                    nextGridA[x][y].a = a + params.timeStep * (deltaA + params.feedRate * (1 - a));
+                    nextGridA[x][y].b = b + params.timeStep * (deltaB - params.killRate * (1 + params.feedRate) * b);
+                }
+            }
+
+            // Swap grids
+            [gridA, nextGridA] = [nextGridA, gridA];
+        }
+
+        // Laplacian for A
+        function laplaceA(x, y) {
+            return (gridA[x+1][y].a + gridA[x-1][y].a + gridA[x][y+1].a + gridA[x][y-1].a - 4 * gridA[x][y].a) / 4;
+        }
+
+        // Laplacian for B
+        function laplaceB(x, y) {
+            return (gridA[x+1][y].b + gridA[x-1][y].b + gridA[x][y+1].b + gridA[x][y-1].b - 4 * gridA[x][y].b) / 4;
+        }
+
+        // Draw the system
+        function draw() {
+            ctx.clearRect(0, 0, canvas.width, canvas.height);
+
+            // Scale up the grid to canvas size
+            const scaleX = canvas.width / params.width;
+            const scaleY = canvas.height / params.height;
+
+            for (let x = 0; x < params.width; x++) {
+                for (let y = 0; y < params.height; y++) {
+                    const a = gridA[x][y].a;
+                    const b = gridA[x][y].b;
+                    const value = Math.min(1, a - b);
+                    const index = Math.floor(value * params.palette.length);
+                    const color = params.palette[Math.min(index, params.palette.length - 1)];
+
+                    ctx.fillStyle = color;
+                    ctx.fillRect(
+                        x * scaleX,
+                        y * scaleY,
+                        Math.ceil(scaleX),
+                        Math.ceil(scaleY)
+                    );
+                }
+            }
+        }
+
+        // Animation loop
+        function animate() {
+            step();
+            draw();
+            requestAnimationFrame(animate);
+        }
+
+        // Start with center perturbation
+        gridA[Math.floor(params.width/2)][Math.floor(params.height/2)].a = 0.5;
+        gridA[Math.floor(params.width/2)][Math.floor(params.height/2)].b = 0.25;
+
+        animate();
+    </script>
+</body>
+</html>
+```