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
About the Author
About the Reviewer
Customer Feedback

Octree scene integration

In order to benefit from the Octree, we must integrate it with the scene as an acceleration structure. The OctreeNode structure and its helper functions should not be used outside of the Scene class.

Getting ready

First, we are going to modify the Scene class to hold an Octree. This means dealing with some dynamic memory, so we also need to add a destructor. The copy constructor and assignment operator will be disabled. If an acceleration structure is present, we should forward operations such as raycasting to the accelerator. Of course, the original code needs to stay in place as the acceleration structure is optional.

How to do it…

Follow these steps to integrate the octree into the scene:

  1. Modify the Scene class declared in Scene.h. Add an OctreeNode pointer to serve as the root node of the Octree. Set this pointer to null in the default constructor. The destructor should free this memory if it is allocated. Also, we need to declare the Accelerate helper function: