confetti.js

// confetti.js - downloaded from https://www.cssscript.com/confetti-falling-animation/

var confetti = {
	maxCount: 120,		//set max confetti count
	speed: 6,			//set the particle animation speed
	frameInterval: 15,	//the confetti animation frame interval in milliseconds
	alpha: 1.0,			//the alpha opacity of the confetti (between 0 and 1, where 1 is opaque and 0 is invisible)
	gradient: false,	//whether to use gradients for the confetti particles
	start: null,		//call to start confetti animation (with optional timeout in milliseconds, and optional min and max random confetti count)
	stop: null,			//call to stop adding confetti
	toggle: null,		//call to start or stop the confetti animation depending on whether it's already running
	pause: null,		//call to freeze confetti animation
	resume: null,		//call to unfreeze confetti animation
	togglePause: null,	//call to toggle whether the confetti animation is paused
	remove: null,		//call to stop the confetti animation and remove all confetti immediately
	isPaused: null,		//call and returns true or false depending on whether the confetti animation is paused
	isRunning: null		//call and returns true or false depending on whether the animation is running
};

	confetti.start = startConfetti;
	confetti.stop = stopConfetti;
	confetti.toggle = toggleConfetti;
	confetti.pause = pauseConfetti;
	confetti.resume = resumeConfetti;
	confetti.togglePause = toggleConfettiPause;
	confetti.isPaused = isConfettiPaused;
	confetti.remove = removeConfetti;
	confetti.isRunning = isConfettiRunning;
	var supportsAnimationFrame = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame;
	var colors = ["rgba(30,144,255,", "rgba(107,142,35,", "rgba(255,215,0,", "rgba(255,192,203,", "rgba(106,90,205,", "rgba(173,216,230,", "rgba(238,130,238,", "rgba(152,251,152,", "rgba(70,130,180,", "rgba(244,164,96,", "rgba(210,105,30,", "rgba(220,20,60,"];
	var streamingConfetti = false;
	var animationTimer = null;
	var pause = false;
	var lastFrameTime = Date.now();
	var particles = [];
	var waveAngle = 0;
	var context = null;

	function resetParticle(particle, width, height) {
		particle.color = colors[(Math.random() * colors.length) | 0] + (confetti.alpha + ")");
		particle.color2 = colors[(Math.random() * colors.length) | 0] + (confetti.alpha + ")");
		particle.x = Math.random() * width;
		particle.y = Math.random() * height - height;
		particle.diameter = Math.random() * 10 + 5;
		particle.tilt = Math.random() * 10 - 10;
		particle.tiltAngleIncrement = Math.random() * 0.07 + 0.05;
		particle.tiltAngle = Math.random() * Math.PI;
		return particle;
	}

	function toggleConfettiPause() {
		if (pause)
			resumeConfetti();
		else
			pauseConfetti();
	}

	function isConfettiPaused() {
		return pause;
	}

	function pauseConfetti() {
		pause = true;
	}

	function resumeConfetti() {
		pause = false;
		runAnimation();
	}

	function runAnimation() {
		if (pause)
			return;
		else if (particles.length === 0) {
			context.clearRect(0, 0, window.innerWidth, window.innerHeight);
			animationTimer = null;
		} else {
			var now = Date.now();
			var delta = now - lastFrameTime;
			if (!supportsAnimationFrame || delta > confetti.frameInterval) {
				context.clearRect(0, 0, window.innerWidth, window.innerHeight);
				updateParticles();
				drawParticles(context);
				lastFrameTime = now - (delta % confetti.frameInterval);
			}
			animationTimer = requestAnimationFrame(runAnimation);
		}
	}

	function startConfetti(timeout, min, max) {
	var width = window.innerWidth;
	var height = window.innerHeight;
	window.requestAnimationFrame = (function() {
		return window.requestAnimationFrame ||
			window.webkitRequestAnimationFrame ||
			window.mozRequestAnimationFrame ||
			window.oRequestAnimationFrame ||
			window.msRequestAnimationFrame ||
			function (callback) {
				return window.setTimeout(callback, confetti.frameInterval);
			};
	})();
	var canvas = document.getElementById("confetti-canvas");
	if (canvas === null) {
		canvas = document.createElement("canvas");
		canvas.setAttribute("id", "confetti-canvas");
		canvas.setAttribute("style", "display:block;z-index:999999;pointer-events:none;position:fixed;top:0");
		document.body.prepend(canvas);
		canvas.width = width;
		canvas.height = height;
		window.addEventListener("resize", function() {
			canvas.width = window.innerWidth;
			canvas.height = window.innerHeight;
		}, true);
		context = canvas.getContext("2d");
	} else if (context === null)
		context = canvas.getContext("2d");
	var count = confetti.maxCount;
	if (min) {
		if (max) {
			if (min == max)
				count = particles.length + max;
			else {
				if (min > max) {
					var temp = min;
					min = max;
					max = temp;
				}
				count = particles.length + ((Math.random() * (max - min) + min) | 0);
			}
		} else
			count = particles.length + min;
	} else if (max)
		count = particles.length + max;
	while (particles.length < count)
		particles.push(resetParticle({}, width, height));
	streamingConfetti = true;
	pause = false;
	runAnimation();
	if (timeout) {
		window.setTimeout(stopConfetti, timeout);
	}
	}

	function stopConfetti() {
	streamingConfetti = false;
	}

	function removeConfetti() {
	stop();
	pause = false;
	particles = [];
	}

	function toggleConfetti() {
	if (streamingConfetti)
		stopConfetti();
	else
		startConfetti();
	}

	function isConfettiRunning() {
	return streamingConfetti;
	}

function drawParticles(context) {
	var particle;
	var x, y, x2, y2;
	for (var i = 0; i < particles.length; i++) {
		particle = particles[i];
		context.beginPath();
		context.lineWidth = particle.diameter;
		x2 = particle.x + particle.tilt;
		x = x2 + particle.diameter / 2;
		y2 = particle.y + particle.tilt + particle.diameter / 2;
		if (confetti.gradient) {
			var gradient = context.createLinearGradient(x, particle.y, x2, y2);
			gradient.addColorStop("0", particle.color);
			gradient.addColorStop("1.0", particle.color2);
			context.strokeStyle = gradient;
		} else
			context.strokeStyle = particle.color;
		context.moveTo(x, particle.y);
		context.lineTo(x2, y2);
		context.stroke();
	}
}

function updateParticles() {
	var width = window.innerWidth;
	var height = window.innerHeight;
	var particle;
	waveAngle += 0.01;
	for (var i = 0; i < particles.length; i++) {
		particle = particles[i];
		if (!streamingConfetti && particle.y < -15)
			particle.y = height + 100;
		else {
			particle.tiltAngle += particle.tiltAngleIncrement;
			particle.x += Math.sin(waveAngle) - 0.5;
			particle.y += (Math.cos(waveAngle) + particle.diameter + confetti.speed) * 0.5;
			particle.tilt = Math.sin(particle.tiltAngle) * 15;
		}
		if (particle.x > width + 20 || particle.x < -20 || particle.y > height) {
			if (streamingConfetti && particles.length <= confetti.maxCount)
				resetParticle(particle, width, height);
			else {
				particles.splice(i, 1);
				i--;
			}
		}
	}
}

export { startConfetti, stopConfetti, removeConfetti }