JSFiddle - React, Tailwind, and code Playground

by dafin defandaky

HTML

<canvas id="canvas" width="300" height="300">

CSS

body {
	background: #333;
}
/*Centering the gauge*/
#canvas {
	display: block;
	width: 300px;
	margin: 100px auto;
}
/*Custom font for numbers*/
@font-face {
	font-family: "bebas";
	src: url("http://thecodeplayer.com/uploads/fonts/BebasNeue.otf");
}

JavaScript

window.onload = function(){
	//canvas initialization
	var canvas = document.getElementById("canvas");
	var ctx = canvas.getContext("2d");
	//dimensions
	var W = canvas.width;
	var H = canvas.height;
	//Variables
	var degrees = 0;
	var new_degrees = 0;
	var difference = 0;
	var color = "lightgreen"; //green looks better to me
	var bgcolor = "#222";
	var text;
	var animation_loop, redraw_loop;
	
	function init()
	{
		//Clear the canvas everytime a chart is drawn
		ctx.clearRect(0, 0, W, H);
		
		//Background 360 degree arc
		ctx.beginPath();
		ctx.strokeStyle = bgcolor;
		ctx.lineWidth = 30;
		ctx.arc(W/2, H/2, 100, 0, Math.PI*2, false); //you can see the arc now
		ctx.stroke();
		
		//gauge will be a simple arc
		//Angle in radians = angle in degrees * PI / 180
		var radians = degrees * Math.PI / 180;
		ctx.beginPath();
		ctx.strokeStyle = color;
		ctx.lineWidth = 30;
		//The arc starts from the rightmost end. If we deduct 90 degrees from the angles
		//the arc will start from the topmost end
		ctx.arc(W/2, H/2, 100, 0 - 90*Math.PI/180, radians - 90*Math.PI/180, false); 
		//you can see the arc now
		ctx.stroke();
		
		//Lets add the text
		ctx.fillStyle = color;
		ctx.font = "50px bebas";
		text = Math.floor(degrees/360*100) + "%";
		//Lets center the text
		//deducting half of text width from position x
		text_width = ctx.measureText(text).width;
		//adding manual value to position y since the height of the text cannot
		//be measured easily. There are hacks but we will keep it manual for now.
		ctx.fillText(text, W/2 - text_width/2, H/2 + 15);
	}
	
	function draw()
	{
		//Cancel any movement animation if a new chart is requested
		if(typeof animation_loop != undefined) clearInterval(animation_loop);
		
		//random degree from 0 to 360
		new_degrees = Math.round(Math.random()*360);
		difference = new_degrees - degrees;
		//This will animate the gauge to new positions
		//The animation will take 1 second
		//time for each frame is 1sec / difference in...