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
About the Author
About the Reviewer

Drawing gradients

Here we implement some effects. Applying a gradient is quite a colorful activity. The output of our recipe demonstrating gradients looks like this:

How to do it…

The recipe uses four new methods, namely createRadialGradient(), createLinearGradient(), addColorStop(), and rgb(). The recipe is as follows.

The HTML code:

<script src="gradients.js"></script>
<body onload="init()">
<canvas id="MyCanvasArea" width="500" height="200" style="border:2px solid blue;" >
your browser does not support canvas</canvas>
<h1>Radial and Linear Gradient</h1>

The JavaScript code:

function init()
  var can=document.getElementById("MyCanvasArea");
  var ctx=can.getContext("2d");     

  //coordinates of center of 1st circle and a radius  
  var x1 = 100;   // x of 1. circle center point
  var y1 = 100;   // y of 1. circle center point
  var r1 = 30;  ...