Eberly - Game Physics

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Library of Congress Cataloging-in-Publication Data

Eberly, David H.
Game physics / David H. Eberly. 2nd ed.
p. cm.
Includes bibliographical references and index.
ISBN 978-0-12-374903-1 (hardcover: alk. paper)
1. Computer gamesProgramming. 2. PhysicsComputer simulation. 3. Computer graphics.
4. Three-dimensional display systems. I. Title.
QA76.76.C672E24 2010
794.81526dc22

2009049828

British Library Cataloguing-in-Publication Data

A catalogue record for this book is available from the British Library.

ISBN: 978-0-12-374903-1

For information on all Morgan Kaufmann publications visit our Web site at www.elsevierdirect.com

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Printed in the United States of America

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After surgery for Stage 4 gallbladder cancer, aggressive chemotherapy, and radiation treatments, it was not clear I would ever have a chance to write the second edition of this book. My survival is a testament to the advances that modern medicine has made. The unselfish caregiving by my loving wife, Shelly, her support through difficult times, and her encouragement for me to recover and continue writing are things for which I am extremely grateful. I have finished this book and look forward to writing many more with her at my side.

The following trademarks, mentioned in this book and the accompanying CD-ROM, are the property of the following organizations.

DirectX, Direct3D, Visual C++, DOS, Windows, and Xbox 360 are trademarks of Microsoft Corporation.

Playstation 3 is a trademark of Sony Corporation.

OpenGL is a trademark of Silicon Graphics, Inc.

Radeon is a trademark of ATI Technologies, Inc.

NVIDIA, GeForce, PhysX, and the Cg Language are trademarks of NVIDIA Corporation.

NetImmerse and R-Plus are trademarks of Numerical Design, Ltd.

MathEngine is a trademark of Criterion Studios.

The Havok physics engine is a trademark of Havok.com Inc.

SoftImage is a trademark of Avid Technology, Inc.

Prince of Persia 3D is a trademark of Brderbund Software, Inc.

XS-G and Canyon Runner are trademarks of Greystone Technology.

Mathematica is a trademark of Wolfram Research, Inc.

Turbo Pascal is a trademark of Borland Software Corporation.

The 8086 and Pentium are trademarks of Intel Corporation.

Macintosh and Xcode are trademarks of Apple Corporation.

Gigi and VAX are trademarks of Digital Equipment Corporation.

MASPAR is a trademark of MasPar Computer Corporation.

COLOR PLATES

The Foucault pendulum.

A ball rolling down a hill.

A mass pulley spring system shown at two different times.

Two snapshots of a freely spinning top.

A rope modeled as a linear chain of springs.

A cloth modeled as a rectangular array of springs.

A gelatinous cube that is oscillating because of random forces.

A gelatinous blob that is oscillating because of small, random forces.

A skirt modeled by a generalized cylinder surface.

A water drop modeled as a control point surface of revolution.

A closed tube surface whose central axis is a helix.

A wriggling snake modeled as a tube surface whose central curve is a control point curve.

Free-form deformation.

A bouncing ball with deformation based on implicit surfaces.

; the direction of rotation is indicated by the arrows. You can see the swirl-like effects of the vortices. Image (d) [lower right]: The grid of image (c) is allowed to evolve further. The density source and sink are more pronounced, and the density is starting to become more homogeneous in regions centered at the vortices.

around a bit. The scene was rotated so you can see the tunnel carved out by the wind. Image (d) [lower right]: The lower-left grid is allowed to evolve further.

Image (a) [top] shows the initial 128 128 64 gray scale image (a CT image). The boundary voxels are drawn in light gray. The z = 0 slice is the upper left tile. The z = 63 slice is the lower right tile. Image (b) [bottom] shows the 3D image after a number of blurring operations.

FIGURES IN CHAPTERS

A couple of coordinate systems at points on a curve.