Book Image

Hands-On C++ Game Animation Programming

By : Gabor Szauer
Book Image

Hands-On C++ Game Animation Programming

By: Gabor Szauer

Overview of this book

Animation is one of the most important parts of any game. Modern animation systems work directly with track-driven animation and provide support for advanced techniques such as inverse kinematics (IK), blend trees, and dual quaternion skinning. This book will walk you through everything you need to get an optimized, production-ready animation system up and running, and contains all the code required to build the animation system. You’ll start by learning the basic principles, and then delve into the core topics of animation programming by building a curve-based skinned animation system. You’ll implement different skinning techniques and explore advanced animation topics such as IK, animation blending, dual quaternion skinning, and crowd rendering. The animation system you will build following this book can be easily integrated into your next game development project. The book is intended to be read from start to finish, although each chapter is self-contained and can be read independently as well. By the end of this book, you’ll have implemented a modern animation system and got to grips with optimization concepts and advanced animation techniques.
Table of Contents (17 chapters)

Implementing dual quaternions

In this section, you will implement dual quaternions in code. By the end of this section, you will have implemented a dual quaternion struct, along with all the mathematical functions needed for using dual quaternions to skin a mesh.

Dual quaternions need to be implemented as structures, similar to transforms or matrices. Create two new files, DualQuaternion.h and DualQuaternion.cpp. You will implement the math relevant to dual quaternions in these files.

Start by declaring a DualQuaternion structure. This structure will allow you to access the data in the dual quaternion struct as two quaternions or a floating-point array of eight numbers. The constructor should set the dual quaternion to identity. The identity dual quaternion has an identity quaternion in its real part and a zero quaternion in its dual part, as illustrated in the following code block:

struct DualQuaternion {
    union {
      ...