How to make cloud effect in html5 canvas using javascript

how to make cloud effect in html5 canvas using javascript - Nibunan

how to create cloud in html5 canvas using javascript - Nibunan

how to write program to display cloud effect in html5 canvas using javascript - Nibunan

how to write program to create cloud animation in html5 canvas using javascript - Nibunan

how to write code to create cloud effect in html5 canvas in javascript - Nibunan

Html5 canvas is evolving to give the rich graphics on browser without using flash or other plugins. Html5 canvas is being used in many places like games animations and rich user interfaces on web and so on.This airticle explains how to create cloud effect in html5 canvas using javascript.

Demo

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Source


      <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
      <html xmlns="http://www.w3.org/1999/xhtml">
      <head>
      <title>Creating cloud effect using html5 canvas - Nibunan</title>
      </head>
      <body style="margin: 0px">
      <canvas width="700" height="450" id="drawing-surface"></canvas>
      <script type="text/javascript">
      function Random(range) {
      return Math.floor((Math.random() * range) + 1);
      }
      function RandomFloat(range) {
      return (Math.random() * range) + 1;
      }
      var viewport = new Viewport();
      for (var i = 0; i < 50; i++) {
      var cloud = new CloudParticle();
      viewport.addObject(cloud);
      }
      viewport.init();
      </script>
      </body>
      </html>

    

Viewport


      function Viewport() {
      var me = this;
      me.objects = [];
      var canvas = document.getElementById("drawing-surface");
      function resizeCanvas() {
      canvas.width = window.innerWidth;
      canvas.height = window.innerHeight;
      }
      resizeCanvas();
      window.onresize = function () {
      resizeCanvas();
      }
      var drawingSurface = document.getElementById("drawing-surface").getContext("2d");
      var image = new Image();
      image.src = "background.jpg";
      image.onload = function () {
      me.backgroundImage = image;
      me.doPaint = true;
      }
      me.doPaint = true;
      function drawBackgroundImage() {
      if (me.backgroundImage) {
      drawingSurface.drawImage(me.backgroundImage, 0, 0, canvas.width, canvas.height);
      }
      }
      function drawObjects() {
      for (var i = 0; i < me.objects.length; i++) {
      me.objects[i].paint(drawingSurface);
      }
      }
      me.paintInit = function () {
      me.doPaint = true;
      }
      function paint() {
      me.paintInit();
      if (me.doPaint) {
      drawBackgroundImage();
      drawObjects();
      me.doPaint = false;
      }
      }
      var timer;
      me.init = function () {
      timer = setInterval(function () { paint(); }, 1000 / 30);
      };
      me.repaint = function () {
      me.doPaint = true;
      };
      me.addObject = function (obj) {
      me.objects.push(obj);
      }
      }
    

Cloud Particle


      function CloudParticle() {
      var me = this;
      me.opacity = 10;
      me.color = 'silver';
      me.reset = function () {
      me.wind = RandomFloat(10)+5;
      me.speed = Random(4)-2 ;
      me.radius = 150;
      me.location = { x: 0, y: Random(window.innerHeight) };
      };
      me.reset();
      var image = new Image();
      image.src = "water.png";
      image.onload = function () {
      me.backgroundImage = image;
      }
      me.move = function () {
      if (me.location.x > window.innerWidth || me.location.x < 0 || me.location.y > window.innerHeight) {
      me.reset();
      }

      me.location.x += me.wind;
      me.location.y += me.speed;
      };
      me.paint = function (context) {
      me.move();
      context.beginPath();
      context.arc(me.location.x, me.location.y, me.radius, 0, 2 * Math.PI, false);
      context.fillStyle = me.color;
      context.globalAlpha = me.opacity / 255;
      context.fill();
      context.closePath();
      };
      }