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

Out of bounds!


If you run our current game, you will notice that the robot will go off the screen if you allow him to continue moving to the left or right. When he reaches the edge of the screen, he will keep on moving until he is no longer visible. If you reverse his direction and make him move the same number of steps now, he will reappear on the screen.

Whenever an object reaches the edge of the screen, we often want it to do something special, such as stopping, or turning around. The code that determines when an object has reached a screen edge is known as boundary checking. There are many possibilities for what we can do when an object reaches a boundary:

  • Stop the object

  • Allow the object to continue past the border (and therefore, disappear)

  • Allow the object to continue past the border and reappear at the opposite border (ever played the arcade version of Asteroids?)

  • Scroll the camera and the screen along with the object (aka Mario)

  • Allow the object to rebound off the border (ever played...