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)

Creating quaternions

Quaternions are used to encode rotation data. In code, quaternions will have four components. They resemble vec4 in that they have an x, y, z, and w component.

As with vec4, the w component comes last.

The quat structure should have two constructors. The default constructor creates an identity quaternion, (0, 0, 0, 1). The (0, 0, 0, 1) identity quaternion is like 1. Any number multiplied by 1 remains the same. Similarly, any quaternion multiplied by the identity quaternion remains the same:

Create a new file, quat.h, to declare the quaternion structure. The quat structure is going to be used throughout the rest of this book to represent rotations:

#ifndef _H_QUAT_
#define _H_QUAT_
#include "vec3.h"
#include "mat4.h"
struct quat {
   union {
       struct {
           float x;