Professional HTML5 Mobile Game Development

Creating Your Game’s Structure

The code built so far has been a good way to exercise the canvas capabilities you’ll be using, but it will need to be reorganized to turn it into a useful structure for a game. Now take a step back to look at some of the patterns you want to use putting together the game.

Building Object-Oriented JavaScript

JavaScript is an object-oriented (OO) language. As such, most elements in JavaScript are objects including strings, arrays, functions and, well, objects are objects in the OO sense.

But this doesn’t mean that JavaScript has all the trappings of object-oriented programming (OOP) that you might expect. First, it doesn't have a classical inheritance model. Second, it doesn't have a standard constructor mechanism, relying instead on either constructor functions or object literals.

Instead of classical inheritance, JavaScript implements prototypical inheritance, meaning you can create an object that represents the prototype, or blueprint, for a set of descendant objects that all share the same base functionality

Classical Versus Prototypical Inheritance

Most popular object-oriented languages used today, including Java and C++, rely on classical inheritance, which means object behavior is defined by creating explicit classes and instantiating objects from those classes. JavaScript has a much more fluid method of defining classes based on the idea of prototypes, which means you create an actual object that behaves the way you want and then create ...