Book Image

Game Physics Cookbook

By : Gabor Szauer
Book Image

Game Physics Cookbook

By: Gabor Szauer

Overview of this book

Physics is really important for game programmers who want to add realism and functionality to their games. Collision detection in particular is a problem that affects all game developers, regardless of the platform, engine, or toolkit they use. This book will teach you the concepts and formulas behind collision detection. You will also be taught how to build a simple physics engine, where Rigid Body physics is the main focus, and learn about intersection algorithms for primitive shapes. You’ll begin by building a strong foundation in mathematics that will be used throughout the book. We’ll guide you through implementing 2D and 3D primitives and show you how to perform effective collision tests for them. We then pivot to one of the harder areas of game development—collision detection and resolution. Further on, you will learn what a Physics engine is, how to set up a game window, and how to implement rendering. We’ll explore advanced physics topics such as constraint solving. You’ll also find out how to implement a rudimentary physics engine, which you can use to build an Angry Birds type of game or a more advanced game. By the end of the book, you will have implemented all primitive and some advanced collision tests, and you will be able to read on geometry and linear Algebra formulas to take forward to your own games!
Table of Contents (27 chapters)
Game Physics Cookbook
Credits
About the Author
Acknowledgements
About the Reviewer
Acknowledgements
www.PacktPub.com
Customer Feedback
Preface
Index

Physics system


It is finally time to start implementing a basic Physics Engine. By the end of this chapter we will have particles flying around the screen in a physically realistic way. Before we start implementing our physics simulation, let's take a minute to discuss what we will be simulating, the rigidbody.

A rigidbody is an object that does not change its shape, the object is rigid. Think about dropping a ball filled with air on the ground. At the point of impact the ball would squash, and then it would stretch as it bounces back up. This ball is not rigid; it changes shape (but not volume), which allows it to bounce. Now imagine a ball of solid steel being dropped. It would not change in shape or volume, but it would not bounce either.

Our object can bounce around because we can model the math behind what it would be like if they bounced, but really they will be rigid. Our simulated objects will never change shape as a result of a physical reaction.

A scene can have hundreds of thousands...