Book Image

OpenGL Game Development By Example

By : Stephen Madsen, Robert Madsen
Book Image

OpenGL Game Development By Example

By: Stephen Madsen, Robert Madsen

Overview of this book

OpenGL is one of the most popular rendering SDKs used to develop games. OpenGL has been used to create everything from 3D masterpieces running on desktop computers to 2D puzzles running on mobile devices. You will learn to apply both 2D and 3D technologies to bring your game idea to life. There is a lot more to making a game than just drawing pictures and that is where this book is unique! It provides a complete tutorial on designing and coding games from the setup of the development environment to final credits screen, through the creation of a 2D and 3D game. The book starts off by showing you how to set up a development environment using Visual Studio, and create a code framework for your game. It then walks you through creation of two games–a 2D platform game called Roboracer 2D and a 3D first-person space shooter game–using OpenGL to render both 2D and 3D graphics using a 2D coordinate system. You'll create sprite classes, render sprites and animation, and navigate and control the characters. You will also learn how to implement input, use audio, and code basic collision and physics systems. From setting up the development environment to creating the final credits screen, the book will take you through the complete journey of creating a game engine that you can extend to create your own games.
Table of Contents (19 chapters)
OpenGL Game Development By Example
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Someone is listening


Now, it's time to actually write some code to implement input for our game. It turns out that some rudimentary input has already been implemented. This is because Windows is an event driven operating system and is already looking for input to occur. From a simplistic point of view, the main task of Windows (or any modern operating system) is to listen for events, and then do something based on those events.

So, whenever you hit a key on your keyboard, an event is triggered that wakes up Windows and says, "Hey, someone hit the keyboard!" Windows then passes that information to any programs that happen to be listening to keyboard events. The same occurs when you use the mouse.

The WndProc event listener

We have already told our program that we want it to listen to events. Open RoboRacer.cpp and locate the WndProc function. WndProc is part of the code that was created for us when use used the Win32 Project template to start our game. WndProc is known as a callback function...