js-ramblings/Firework Particles.html at main · abuzant/js-ramblings · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Fireworks Trail with Counter</title>
    <style>
        body, html {
            margin: 0;
            padding: 0;
            overflow: hidden;
            background-color: white;
        }
        canvas {
            display: block;
        }
        #counter {
            position: absolute;
            top: 10px;
            right: 20px;
            font-size: 18px;
            font-family: Arial, sans-serif;
            color: black;
            background: rgba(255, 255, 255, 0.7);
            padding: 5px 10px;
            border-radius: 5px;
            box-shadow: 0 0 5px rgba(0, 0, 0, 0.3);
        }
    </style>
</head>
<body>
    <canvas id="fireworksCanvas"></canvas>
    <div id="counter">Particles: 0</div>

    <script>
        const canvas = document.getElementById('fireworksCanvas');
        const ctx = canvas.getContext('2d');
        const counter = document.getElementById('counter');

        canvas.width = window.innerWidth;
        canvas.height = window.innerHeight;

        window.addEventListener('resize', () => {
            canvas.width = window.innerWidth;
            canvas.height = window.innerHeight;
        });

        const fireworks = [];

        class Firework {
            constructor(x, y) {
                this.x = x;
                this.y = y;
                this.particles = [];
                this.createParticles();
            }

            createParticles() {
                const colors = ['#FF1461', '#18FF92', '#5A87FF', '#FBF38C', '#FF7F50', '#FFD700'];
                const color = colors[Math.floor(Math.random() * colors.length)];
                for (let i = 0; i < 25; i++) {
                    const angle = Math.random() * 2 * Math.PI;
                    const speed = Math.random() * 4 + 1;
                    const size = Math.random() * 3 + 2;
                    this.particles.push({
                        x: this.x,
                        y: this.y,
                        speedX: Math.cos(angle) * speed,
                        speedY: Math.sin(angle) * speed,
                        size: size,
                        alpha: 1,
                        color: color
                    });
                }
            }

            update() {
                this.particles.forEach(particle => {
                    particle.x += particle.speedX;
                    particle.y += particle.speedY;
                    particle.alpha -= 0.025;
                });
                this.particles = this.particles.filter(p => p.alpha > 0);
            }

            draw() {
                this.particles.forEach(particle => {
                    ctx.beginPath();
                    ctx.arc(particle.x, particle.y, particle.size, 0, Math.PI * 2);
                    ctx.fillStyle = `rgba(${hexToRgb(particle.color)}, ${particle.alpha})`;
                    ctx.shadowBlur = 25;
                    ctx.shadowColor = particle.color;
                    ctx.fill();
                });
            }
        }

        function hexToRgb(hex) {
            const bigint = parseInt(hex.slice(1), 16);
            const r = (bigint >> 16) & 255;
            const g = (bigint >> 8) & 255;
            const b = bigint & 255;
            return `${r}, ${g}, ${b}`;
        }

        canvas.addEventListener('mousemove', (e) => {
            fireworks.push(new Firework(e.clientX, e.clientY));
        });

        function animate() {
            ctx.clearRect(0, 0, canvas.width, canvas.height);
            let particleCount = 0;

            fireworks.forEach((firework, index) => {
                firework.update();
                firework.draw();
                particleCount += firework.particles.length;
                if (firework.particles.length === 0) {
                    fireworks.splice(index, 1);
                }
            });

            counter.textContent = `Particles: ${particleCount}`;
            requestAnimationFrame(animate);
        }

        animate();
    </script>
</body>
</html>