Book Image

HTML5 Web Application Development By Example : Beginner's guide

By : Jody Gustafson
Book Image

HTML5 Web Application Development By Example : Beginner's guide

By: Jody Gustafson

Overview of this book

HTML5's new features have made it a real application development platform with widespread adoption throughout the industry for this purpose. Being able to create one application that can run on virtually any device from phone to desktop has made it the first choice among developers. Although JavaScript has been around for a while now, it wasn't until the introduction of HTML5 that we have been able to create dynamic, feature-rich applications rivaling those written for the desktop. HTML5 Web Application Development By Example will give you the knowledge you need to build rich, interactive web applications from the ground up, incorporating the most popular HTML5 and CSS3 features available right now. This book is full of tips, tools, and example applications that will get you started writing your own applications today. HTML5 Web Application Development By Example shows you how to write web applications using the most popular HTML5 and CSS3 features. This book is a practical, hands-on guide with numerous real-world and relevant examples. You will learn how to use local storage to save an application's state and incorporate CSS3 to make it look great. You will also learn how to use custom data attributes to implement data binding. We'll use the new Canvas API to create a drawing application, then use the Audio API to create a virtual piano, before turning it all into a game. The time to start using HTML5 is now. And HTML5 Web Application Development by Example will give you the tips and know-how to get started.
Table of Contents (18 chapters)
HTML5 Web Application Development By Example Beginner's guide
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Time for action – Mandelbrot using a web worker


Now we will implement the same thing except this time we will use a web worker to offload the processing onto another thread. This will free up the main thread to handle page updates and user interaction. You can find the source code for this section in Chapter 9/example9.3.

Let's go into the HTML and add a checkbox where we can select whether to use web workers or not. This will make it easier to compare results in the browser:

<input type="checkbox" id="use-worker" checked />
<label for="use-worker">Use web worker</label>

We'll also add a stop button. There was no way to stop before without web workers because the UI was locked up, but now we will be able to implement it:

<button id="stop">Stop Drawing</button>

Now let's go ahead and create our web worker in a new file named mandelbrotWorker.js. Our worker needs to use the MandelbrotGenerator object so we will import that script into the worker:

importScripts("mandelbrotGenerator...