birth: Chemical Dreams on Dark Skies

2026-05-28 13:47:17 +00:00 · 2026-05-28 13:47:17 +00:00 · 71ab34c7ac
commit 71ab34c7ac
parent 240dc73794
1 changed files with 164 additions and 0 deletions
--- a/index.html
+++ b/index.html
@ -0,0 +1,164 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Chemical Dreams</title>
+    <style>
+        body {
+            margin: 0;
+            overflow: hidden;
+            background: #0a0a0a;
+            color: #ccc;
+            font-family: 'Courier New', monospace;
+        }
+        #canvas {
+            display: block;
+        }
+        #attribution {
+            position: absolute;
+            bottom: 10px;
+            right: 10px;
+            font-size: 10px;
+            color: #555;
+            text-shadow: 0 0 5px rgba(0,0,0,0.5);
+        }
+    </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');
+
+        // Set canvas to full window size
+        function resizeCanvas() {
+            canvas.width = window.innerWidth;
+            canvas.height = window.innerHeight;
+        }
+        window.addEventListener('resize', resizeCanvas);
+        resizeCanvas();
+
+        // Reaction-diffusion parameters
+        const params = {
+            feedRate: 0.055,
+            killRate: 0.062,
+            diffusionRateA: 1,
+            diffusionRateB: 0.5,
+            width: Math.floor(canvas.width / 2),
+            height: Math.floor(canvas.height / 2),
+            cellSize: 2
+        };
+
+        // Initialize grids
+        let grid = new Array(params.width * params.height);
+        let nextGrid = new Array(params.width * params.height);
+
+        // Initialize with random values
+        function initGrid() {
+            for (let i = 0; i < grid.length; i++) {
+                grid[i] = Math.random() * 0.1;
+                nextGrid[i] = grid[i];
+            }
+
+            // Add some initial patterns
+            for (let i = 0; i < params.width * params.height * 0.01; i++) {
+                const idx = Math.floor(Math.random() * grid.length);
+                grid[idx] = 1;
+            }
+        }
+
+        initGrid();
+
+        // Reaction-diffusion kernel
+        function updateGrid() {
+            for (let x = 1; x < params.width - 1; x++) {
+                for (let y = 1; y < params.height - 1; y++) {
+                    const idx = x + y * params.width;
+                    const a = grid[idx];
+                    const b = nextGrid[idx];
+
+                    // Apply reaction-diffusion equations
+                    const reaction = a * b * b;
+                    const feed = params.feedRate * (1 - a);
+                    const kill = params.killRate * a;
+                    const newA = a + (params.diffusionRateA * laplacian(x, y, 'a') - reaction + feed - kill) * 0.1;
+                    const newB = b + (params.diffusionRateB * laplacian(x, y, 'b') + reaction - kill) * 0.1;
+
+                    nextGrid[idx] = newA;
+                    nextGrid[idx + params.width * params.height] = newB;
+                }
+            }
+
+            // Swap grids
+            [grid, nextGrid] = [nextGrid, grid];
+        }
+
+        // Calculate Laplacian for a given cell
+        function laplacian(x, y, type) {
+            let sum = 0;
+            const centerIdx = x + y * params.width;
+
+            for (let dx = -1; dx <= 1; dx++) {
+                for (let dy = -1; dy <= 1; dy++) {
+                    const idx = (x + dx) + (y + dy) * params.width;
+                    if (type === 'a') {
+                        sum += grid[idx];
+                    } else {
+                        sum += nextGrid[idx + params.width * params.height];
+                    }
+                }
+            }
+
+            return (sum - 9 * (type === 'a' ? grid[centerIdx] : nextGrid[centerIdx])) / 9;
+        }
+
+        // Draw the grid
+        function drawGrid() {
+            ctx.clearRect(0, 0, canvas.width, canvas.height);
+
+            // Create image data for better performance
+            const imageData = ctx.createImageData(params.width, params.height);
+            const data = imageData.data;
+
+            for (let i = 0; i < grid.length; i++) {
+                const valA = Math.min(1, Math.max(0, grid[i]));
+                const valB = Math.min(1, Math.max(0, nextGrid[i + params.width * params.height]));
+
+                // Convert reaction-diffusion values to color
+                const r = Math.floor(valA * 255);
+                const g = Math.floor((valA + valB) * 127);
+                const b = Math.floor(valB * 255);
+
+                const idx = i * 4;
+                data[idx] = r;
+                data[idx + 1] = g;
+                data[idx + 2] = b;
+                data[idx + 3] = 255;
+            }
+
+            // Draw to canvas with scaling
+            const tempCanvas = document.createElement('canvas');
+            const tempCtx = tempCanvas.getContext('2d');
+            tempCanvas.width = params.width;
+            tempCanvas.height = params.height;
+            tempCtx.putImageData(imageData, 0, 0);
+
+            ctx.imageSmoothingEnabled = false;
+            ctx.drawImage(tempCanvas,
+                0, 0, params.width, params.height,
+                0, 0, canvas.width, canvas.height);
+        }
+
+        // Animation loop
+        function animate() {
+            updateGrid();
+            drawGrid();
+            requestAnimationFrame(animate);
+        }
+
+        animate();
+    </script>
+</body>
+</html>