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)

Understanding cubic Hermite splines

The most common spline type used in animation for games is a cubic Hermite spline. Unlike Bézier, a Hermite spline doesn't use points in space for its control; rather, it uses the tangents of points along the spline. You still have four values, as with a Bézier spline, but they are interpreted differently.

With the Hermite spline, you don't have two points and two control points; instead, you have two points and two slopes. The slopes are also referred to as tangents—throughout the rest of this chapter, the slope and tangent terms will be used interchangeably. The point basis functions for Hermite splines look as follows:

Figure 8.7: The point basis functions of Hermite splines

Figure 8.7: The point basis functions of Hermite splines

When given the point basis functions, you can implement the spline evaluation function similar to how the Bézier interpolation function was implemented:

template<typename T>
T Hermite(float t, T&amp...