Book Image

SDL Game Development

By : Shaun Mitchell
5 (1)
Book Image

SDL Game Development

5 (1)
By: Shaun Mitchell

Overview of this book

SDL 2.0 is the latest release of the popular Simple DirectMedia Layer API, which is designed to make life easier for C++ developers, allowing you simple low-level access to various multiplatform audio, graphics, and input devices.SDL Game Development guides you through creating your first 2D game using SDL and C++. It takes a clear and practical approach to SDL game development, ensuring that the focus remains on creating awesome games.Starting with the installation and setup of SDL, you will quickly become familiar with useful SDL features, covering sprites, state management, and OOP, leading to a reusable framework that is extendable for your own games. SDL Game Development culminates in the development of two exciting action games that utilize the created framework along with tips to improve the framework.
Table of Contents (16 chapters)
SDL Game Development
About the Author
About the Reviewers

Implementing polymorphism

This leads us to our next OOP feature, polymorphism. What polymorphism allows us to do is to refer to an object through a pointer to its parent or base class. This may not seem powerful at first, but what this will allow us to do is essentially have our Game class need only to store a list of pointers to one type and any derived types can also be added to this list.

Let us take our GameObject and Player classes as examples, with an added derived class, Enemy. In our Game class we have an array of GameObject*:

std::vector<GameObject*> m_gameObjects;

We then declare four new objects, all of which are GameObject*:

GameObject* m_player;
GameObject* m_enemy1;
GameObject* m_enemy2;
GameObject* m_enemy3;

In our Game::init function we can then create instances of the objects using their individual types:

m_player = new Player();
m_enemy1 = new Enemy();
m_enemy2 = new Enemy();
m_enemy3 = new Enemy();

Now they can be pushed into the array of GameObject*: