live - 60fps 1920 x 1080
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Supernova Collapse & Rebirth</title>
<style>
body {
margin: 0;
height: 100vh;
overflow: hidden;
background: radial-gradient(ellipse at center, #1b2735 0%, #090a0f 100%);
}
canvas {
display: block;
}
</style>
</head>
<body>
<canvas id="particle-canvas"></canvas>
<script>
const canvas = document.getElementById('particle-canvas');
const ctx = canvas.getContext('2d');
let width, height, centerX, centerY;
let particles = [];
const particleCount = 2000;
const animationDuration = 10000; // 10 seconds in ms
function resizeCanvas() {
width = canvas.width = window.innerWidth;
height = canvas.height = window.innerHeight;
centerX = width / 2;
centerY = height / 2;
}
window.addEventListener('resize', resizeCanvas);
resizeCanvas();
class Particle {
constructor() {
this.angle = Math.random() * Math.PI * 2;
this.radius = Math.random() * 1.5 + 0.5;
this.speed = Math.random() * 400 + 200; // pixels per second during explosion
this.maxDistance = Math.random() * Math.max(width, height) * 0.6;
}
update(progress) {
// Easing function: explosive start, slow down, then accelerate back
// The function goes from 0 -> 1 -> 0 over the duration
let easedProgress = 1 - Math.pow(Math.abs(progress - 0.5) * 2, 2);
let currentDistance = easedProgress * this.maxDistance;
this.x = centerX + Math.cos(this.angle) * currentDistance;
this.y = centerY + Math.sin(this.angle) * currentDistance;
// Determine previous position for motion blur trail
let prevDistance = (1 - Math.pow(Math.abs((progress - 0.01) - 0.5) * 2, 2)) * this.maxDistance;
this.prevX = centerX + Math.cos(this.angle) * prevDistance;
this.prevY = centerY + Math.sin(this.angle) * prevDistance;
// Color changes based on the phase (explosion vs. collapse)
if (progress < 0.5) { // Explosion phase
this.color = `hsl(50, 100%, ${60 + easedProgress * 40}%)`;
} else { // Collapse phase
this.color = `hsl(240, 100%, ${60 + easedProgress * 40}%)`;
}
}
draw() {
ctx.beginPath();
ctx.moveTo(this.prevX, this.prevY);
ctx.lineTo(this.x, this.y);
ctx.strokeStyle = this.color;
ctx.lineWidth = this.radius * 2;
ctx.stroke();
}
}
function init() {
particles = [];
for (let i = 0; i < particleCount; i++) {
particles.push(new Particle());
}
}
function animate(timestamp) {
const elapsed = timestamp % animationDuration;
const progress = elapsed / animationDuration;
// Fading effect
ctx.fillStyle = 'rgba(10, 10, 20, 0.1)';
ctx.fillRect(0, 0, width, height);
ctx.lineCap = 'round';
particles.forEach(p => {
p.update(progress);
p.draw();
});
requestAnimationFrame(animate);
}
init();
requestAnimationFrame(animate);
</script>
</body>
</html>About this animation
Explosive supernova event and rebirth.
Under the hood
State-Machine Flow
This uses a complex Javascript state-machine. Particles begin in an 'expansion' state radiating outward, transition to a 'pause' state halting velocity, shrink rapidly in a 'collapse' state toward the origin point, and finally blast outward in 'rebirth'.
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