Sadun E. - iOS Drawing: Practical UIKit Solutions

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Practical UIKit Solutions

Erica Sadun

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AirPlay, AirPort, AirPrint, AirTunes, App Store, Apple, the Apple logo, Apple TV, Aqua, Bonjour, the Bonjour logo, Cocoa, Cocoa Touch, Cover Flow, Dashcode, Finder, Fire-Wire, iMac, Instruments, Interface Builder, iOS, iPad, iPhone, iPod, iPod touch, iTunes, the iTunes logo, Leopard, Mac, Mac logo, Macintosh, Multi-Touch, Objective-C, Quartz, QuickTime, QuickTime logo, Safari, Snow Leopard, Spotlight, and Xcode are trademarks of Apple, Inc., registered in the United States and other countries. OpenGL, or OpenGL Logo,: OpenGL is a registered trademark of Silicon Graphics, Inc. The YouTube logo is a trademark of Google, Inc. Intel, Intel Core, and Xeon are trademarks of Intel Corp. in the United States and other countries.

ISBN-13: 978-0-321-94787-1
ISBN-10: 0-321-94787-8

Editor-in-Chief
Mark Taub

Senior Acquisitions Editor
Trina MacDonald

Senior Development Editor
Chris Zahn

Managing Editor
Kristy Hart

Senior Project Editor
Betsy Gratner

Copy Editor
Kitty Wilson

Proofreader
Anne Goebel

Technical Reviewer
Richard Wardell

Editorial Assistant
Olivia Basegio

Cover Designer
Chuti Prasertsith

For my kids. Hang in there, guys! I love you.

No book is the work of one person. I want to thank my team, who made this possible. The lovely Trina MacDonald green-lighted this title, so you have the opportunity now to read it. Chris Zahn is my wonderful development editor, and Olivia Basegio makes everything work even when things go wrong.

I send my thanks to the entire Addison-Wesley/Pearson production team, specifically Kristy Hart, Betsy Gratner, Kitty Wilson, Anne Goebel, and Chuti Prasertsith.

Thanks go as well to Stacey Czarnowski, my new agent now that Neil Salkind retired; to Rich Wardwell, my technical editor; and to my colleagues, both present and former, at TUAW and the other blogs Ive worked at.

I am deeply indebted to the wide community of iOS developers who have supported me in IRC and who helped read this book and offer feedback. Particular thanks go to Oliver Drobnik, Aaron Basil (Ethervision), Harsh Trivedi, Michael Prenez-Isbell, Alex Hertzog, Neil Taylor, Maurice Sharp, Rod Strougo, Chris Samuels, Wess Cope, Hamish Allan, Jeremy Tregunna, Mahipal Raythattha, Eddie Kim, Jeremy Sinclair, Jeff Tentschert, Greg Hartstein, Mike Greiner, Ajay Gautam, Shane Zatezalo, Doug Drummond, Wil Macaulay, Mike Kale, Bill DeMuro, Evan Stone, Ashley Ward, Nick Pannuto, Diederik Hoogenboom, Nico Ameghino, Duncan Champney, August Joki, Remy psy Demarest, Joshua Weinburg, Emanuele Vulcano, and Charles Choi. Their techniques, suggestions, and feedback helped make this book possible. If I have overlooked anyone who helped contribute, please accept my apologies for the oversight.

Special thanks also go to my husband and kids. You are wonderful.

Erica Sadun is the bestselling author, coauthor, and contributor to several dozen books on programming, digital video and photography, and web design, including the widely popular The Core iOS 6 Developers Cookbook, Fourth Edition. She currently blogs at TUAW.com and has blogged in the past at OReillys Mac Devcenter, Lifehacker, and Ars Technica. In addition to being the author of dozens of iOS-native applications, Erica holds a Ph.D. in computer science from Georgia Techs Graphics, Visualization, and Usability Center. A geek, a programmer, and an author, shes never met a gadget she didnt love. When not writing, she and her geek husband parent three geeks-in-training, who regard their parents with restrained bemusement when theyre not busy rewiring the house or plotting global dominance.

Apple has lavished iOS with a rich and evolving library of 2D drawing utilities. These APIs include powerful features like transparency, path-based drawing, antialiasing, and more. They offer low-level, lightweight, easy-to-integrate drawing routines that you can harness to build images, to display views, and to print.