Kevin Brothaler - OpenGL ES 2 for Android: a quick-start guide

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To Anne and my Oma

You have brought so much joy and wonder into my life. Thank you for making it all possible.

Games are visual experiences. As game developers, we want to create environments and characters that pull players into our games, be it through stunningly realistic 3D scenery or quirky, out-of-this-world experiences. We are longing for millions to play our games and experience our worlds, making their lives a tiny bit more fun. Android and its ecosystem provide us with an audience. OpenGL ES gives us the technological means to realize the games of our dreams.

OpenGL ES is the de facto standard in mobile graphics programming. Its the lean and mean brother of desktop OpenGL, removing a lot of the cruft kept for backward compatibility. OpenGL ES comes in three major versions: version 1.0, which gave us an inflexible fixed-function pipeline; version 2.0, which introduced a programmable pipeline with all the bells and whistles we can ask for; and finally, the very young and not-yet-widely-available version 3.0, which adds new features on top of the 2.0 standard.

While OpenGL ES has been in use for almost a decade, hands-on material for beginners is hard to come by, especially for version 2.0, which introduced shaders, an esoteric topic for newcomers. In addition to device- and platform-specific issues, this lack of material sets the entry barrier rather high.

This is where Kevins book comes in. He cuts through all the boilerplate talk and takes you on a pragmatic tour of OpenGL ES 2.0. Not only does Kevin cover the fundamental concepts behind 3D graphics, but he also documents all the Android-specific pitfalls you run into. Even experienced developers will find a few nuggets here. To paraphrase: Its dangerous to go it alone, so read this book!

Creator of libgdx,

I am so grateful to the wonderful team over at The Pragmatic Programmers for giving me the chance to write this book and for doing such a great job in helping me bring it to completion. When I first started out, I wasnt quite sure what to expect, but they did an excellent job of teaching me the ropes. I owe a special debt of gratitude to my editor, Susannah Pfalzer, for guiding me so expertly through the process, and to Aron Hsiao for skillfully coaching a new and bewildered author to the Pragmatic writing style.

I am also thankful for all of my technical reviewers and for everyone else who provided invaluable feedback, including (in no particular order) Mario Zechner, Owen Alanzo Hogarth, Sam Rose, Mike Riley, Aaron Kalair, Rene van der Lende, John Horton, Ed Burnette, Mark Guerra, Maik Schmidt, Kevin Gisi, Brian Schau, Marius Marinescu, Stephen Wolff, Haress Das, Bill Yee, Chad Dumler-Montplaisir, Tibor Simic, Michael Hunter, Jonathan Mischo, and Stefan Turalski, as well as everyone who reported errata or sent in their feedback. Your feedback and advice helped to greatly improve the book, and your encouragement is much appreciated.

I couldnt have done it without the support of the greater community and the generosity of those willing to share their knowledge, including my wonderful readers over at Learn OpenGL ES, the guys at the Khronos Group, NeHe Productions, the Android team, John Carmack, and all of the other giants whom I may have missed and who are too numerous to mention. I stand on their shoulders, and this work wouldnt be possible without them.

Perhaps my greatest debt of gratitude goes to the two women in my life who have kept me grounded all this time: my Oma, for showing me that a little bit of toughness can go a long way, and Anne, my fiance, for letting me spend so many hours tucked away in my home office and for being so encouraging from beginning to end.