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 constraints

Both CCD and FABRIK solvers produce good results, but neither produces predictable results. In this section, you will learn what constraints are, where the IK solver constraints can be applied, and how to apply constraints. This will let you build much more realistic IK solvers.

Consider an IK chain that is supposed to represent a leg. You would want to make sure that the motion of each joint is predictable, for example, the knee should probably not bend forward.

This is where constraints are useful. The knee joint is a hinge; if a hinge constraint is applied, the leg IK chain will look more realistic. Using constraints, you can set rules for each joint in an IK chain.

The following steps will show you where to apply constraints in both the CCD and FABRIK solvers:

  1. Constraints can be applied to both CCD and FABRIK solvers, and they must be applied after each iteration. For CCD, this means inserting a bit of code here:
    bool CCDSolver::Solve(const...