Book Image

Canvas Cookbook

Book Image

Canvas Cookbook

Overview of this book

With the growing popularity of HTML5 Canvas, this book offers tailored recipes to help you develop portable applications, presentations, and games. The recipes are simple yet creative and build on each other. At every step, the book inspires the reader to develop his/her own recipe. From basic to advanced, every aspect of Canvas API has been covered to guide readers to develop their own application, presentation, or game.
Table of Contents (16 chapters)
Canvas Cookbook
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Drawing and cropping an image


Let's jump right in by drawing a simple image. In this recipe, you'll learn how to load an image and draw it on the canvas. Also, you will learn to crop an image:

Follow these steps to draw an image on the canvas.

How to do it

The HTML code to complete this recipe is as follows:

<html>
<head>
<title>Image</title>
<script src="ImageDrawing.js"></script>
</head>
<body onload="init();">
<center>
<canvas id="MyCanvasArea" width="900" height="420" style="border:2px solid blue;" >your browser does not support canvas</canvas>
<h1>An Image</h1>
</center>
</body>
</html>

The JavaScript code:

var can;
var ctx;
var boyimage;
function init()
{
  can = document.getElementById('MyCanvasArea'),
  ctx = can.getContext('2d');

  draw();

  function draw()
  {
    boyimage = new Image();
    boyimage.src = 'Images/ohams.png';
    boyimage.onload = function(){
      ctx.drawImage(boyimage...