iOS Drawing Practical UIKit Solutions

309 Pages·2013·6.563 MB·English

by  Erica Sadun

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iOS Drawing
ptg11539604
ptg11539604
iOS Drawing
Practical UIKit Solutions
Erica Sadun

ptg11539604

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ISBN-13: 978-0-321-94787-1
ISBN-10: 0-321-94787-8
❖
For my kids. Hang in there, guys! I love you.
❖
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Contents at a Glance
Preface
1 Drawing Contexts
2 The Language of Geometry
3 Drawing Images
4 Path Basics
5 Paths in Depth
6 Drawing Gradients
7 Masks, Blurs, and Animation
8 Drawing Text
A Blend Modes
B Miter Threshold Limits
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Contents
Preface
How This Book Is Organized
About the Sample Code
Contacting the Author
1 Drawing Contexts
Frameworks
When to Draw
Contexts
Establishing Contexts in UIKit
Building Contexts in Quartz
Drawing into Contexts
Drawing Within a UIKit Context
UIKit and Quartz Colors
The Painter’s Model
Context State
Context Coordinate System
Clipping
Transforms
Setting Line Parameters
Summary
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2 The Language of Geometry
Points Versus Pixels
View Coordinates
Key Structures
Using CGRectDivide()
Rectangle Utilities
Fitting and Filling
Summary
3 Drawing Images
UIKit Images
Building Thumbnails
Extracting Subimages
Converting an Image to Grayscale
Watermarking Images
Retrieving Image Data
Creating Images from Bytes
Drawing and Auto Layout
Building Stretchable Images
Rendering a PDF
Building a Pattern Image
Summary
4 Path Basics
Why Bezier
Class Convenience Methods
Building Paths
Retrieving Path Bounds and Centers
Transforming Paths
Fitting Bezier Paths
Creating Bezier Paths from Strings
Adding Dashes
Building a Polygon Path
Line Joins and Caps
Miter Limits
Inflected Shapes
Summary
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5 Paths in Depth
Path Elements
Converting Bezier Paths into Element Arrays
Legal and Illegal Paths
Math Behind the Path
Calculating Path Distance
Interpolating Paths
Retrieving Subpaths
Inverting Paths
Drawing Shadows
Drawing Inner and Outer Glows
Reversing a Path
Visualizing Path Order
Summary
6 Drawing Gradients
Gradients
Drawing Gradients
Building Gradients
Adding Edge Effects
State and Transparency Layers
Flipping Gradients
Mixing Linear and Radial Gradients
Drawing Gradients on Path Edges
Drawing 3D Letters
Building Indented Graphics
Combining Gradients and Texture
Basic Button Gloss
Adding Bottom Glows
Building an Elliptical Gradient Overlay
Summary
7 Masks, Blurs, and Animation
Drawing into Images with Blocks
Simple Masking
Complex Masking
Blurring
Drawing Reflections ptg11539604
Creating Display Links for Drawing
Building Marching Ants
Drawing Sampled Data
Applying Core Image Transitions
Summary