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

Octree contents


Once we have built an octree, we must manage models that might occupy the same space as the tree. There are three operations that will help us manage models within the tree. We want to know when a model is added to the tree or removed from the tree. We also want to know when a model moves, as it may occupy different leaf nodes at its new position.

Getting ready

In this section, we are going to implement three support functions for the octree. We are going to create an Insert function for when something is added to the tree. We are going to create a Remove function for when something is removed from the tree. And finally, an Update function for when something within the tree moves. The update function will simply remove the model from the tree and reinsert it.

How to do it…

Follow these steps to add objects to the octree or to remove objects from the octree:

  1. Declare the Insert, Remove, and Update functions in Scene.h:

    void Insert(OctreeNode* node, Model* model);
    void Remove(OctreeNode...