How to create realistic under water bubbles in html5 canvas using javascript

how to make under water bubbles effect in html5 canvas using 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 article explains how to create the more realistic under water bubbles 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 under water bubbles 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 < 250; i++) {
      var bubble = new Bubble();
      var size = RandomFloat(15);
      bubble.size = { width: size + 1, height: size + 1 };
      viewport.addObject(bubble);
      }
      for (var i = 0; i < 1000; i++) {
      var bubble = new Bubble();
      var size = RandomFloat(4);
      bubble.size = { width: size + 1, height: size + 1 };
      viewport.addObject(bubble);
      }
      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);
      }
      }
    

Bubble


      function Bubble() {
      var me = this;
      me.reset = function () {
      me.wind = RandomFloat(1) - 1.5;
      me.speed = RandomFloat(5) + 1;
      me.location = { x: RandomFloat(window.innerWidth), y: window.innerHeight };
      };
      me.reset();
      var image = new Image();
      image.src = "bubble.png";
      image.onload = function () {
      me.image = image;
      }
      me.move = function () {
      if (me.location.y < 0 || me.location.x < 0 || me.location.x > window.innerWidth) {
      me.reset();
      }
      me.location.x += me.wind;
      me.location.y -= me.speed;
      };
      me.paint = function (context) {
      if (!me.image) return;
      me.move();
      context.drawImage(me.image, me.location.x, me.location.y,me.size.width,me.size.height);
      };
      }