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)

Blending animations

It is possible to blend between two animations in a vertex shader. There are two reasons why you may would want to avoid blending between animations in a vertex shader. First, doing so will double the amount of texel fetches, which will make the shader more expensive.

This explosion of texel fetches happens because you would have to retrieve two copies of the pose matrices – one for each animation – and then blend between them. The shader code for doing so might look like the following code snippet:

    mat4 pose0a = GetPose(animTexA, joints.x, instance);
    mat4 pose1a = GetPose(animTexA, joints.y, instance);
    mat4 pose2a = GetPose(animTexA, joints.z, instance);
    mat4 pose3a = GetPose(animTexA, joints.w, instance);
    mat4 pose0b = GetPose(animTexB, joints.x, instance);
    mat4 pose1b = GetPose(animTexB, joints.y...