デコレーター（Carlo Chung著「Pro Objective-C Design Patterns for iOS」の英語の章「Decorator」から翻訳）

通常、写真を撮るとき、後から写真を飾る方法は考えません。 瞬間を捉えたいという理由だけで写真を撮ります。 次に、写真の1つを印刷し、それを珍しいガラスのあるフレームに入れることにしたとしましょう。 ただし、後で、同じ写真を別のフレームに配置することもできます。 フレームを変更した場合でも、画像を追加しただけで、同時に変更しなかったため、画像は同じままです。

オブジェクト指向プログラミングでは、元の機能を失うことなく他のオブジェクトに動作を追加するという同様の考え方を取り入れました。つまり、拡張オブジェクトは同じクラスの改良バージョン（フレーム内の写真）になります。 「改善」（フレーム）は、動的に重ね合わせたり削除したりできます。 このデザインパターンをデコレータと呼びます。デコレータを別のデコレータまたはソースオブジェクトに追加してプロパティを拡張し、元の動作をそのまま残すことができるためです。

この章では、まずパターンの概念とそれをいつ使用するかについて説明します。 次に、このパターンを利用して、UIImageオブジェクトの一連のフィルタリングイメージクラスを設計する方法について説明します。

デコレータパターンとは何ですか？

古典的なDecoratorパターンには、親抽象クラスComponentが含まれています。これは、他の特定のコンポーネントの一般的な操作を宣言します。 抽象Componentクラスは、別のDecoratorクラスにラップできます。 Decoratorは、別のComponentへのリンクが含まれていComponent 。 ConcreteDecoratorは、他の同様のComponentおよびDecorator高度な動作を定義し、それに含まれるComponentオブジェクトの操作を実行します。 それらの関係を図16-1に示します。



図16–1。 デコレータパターンクラス図

Componentクラスは抽象operationメソッドを定義し、その具体的なクラスは独自の特定の操作を持つために再定義します。 Decoratorは、オブジェクトにDecoratorを含めることにより、 Component （またはDecorator ）の他のインスタンスを拡張する「装飾」動作を定義する基本クラスです。 デフォルトのoperation方法では、メッセージが含まれるcomponent転送されcomponent 。 ConcreteDecoratorAおよびConcreteDecoratorBは、親operationをオーバーライドして、 superを使用するoperation componentメソッド呼び出しの呼び出しに独自のoperationを追加します。 component 1回だけ展開する必要がある場合は、 Decoratorの基本クラスを無視して、 ConcreteDecoratorすべてのリクエストを直接componentリダイレクトさせることができcomponent 。 これは、図16–2のオブジェクト図に示すように、1つの動作を別の動作の上に追加して一連の操作を形成することに似ています。



図16–2。 Decoratorパターンとその機能の実装

ご注意 デコレータパターン ：追加機能をオブジェクトに動的に追加します。 デコレータは、機能を拡張するための継承の柔軟な代替手段を提供します。

* GoFのデザインパターン（Addison Wesley、1994）に記載されている元の定義。

デコレータパターンはいつ使用しますか？

このパターンの使用を検討する可能性のある3つの一般的な状況があります。

• 他のオブジェクトに影響を与えることなく、動的かつ透過的に個々のオブジェクトに機能を追加します。
• これが実用的ではないクラスの動作を拡張したい場合。 クラス定義を非表示にして継承できない場合や、クラスの動作を拡張するには、機能の各組み合わせをサポートするために膨大な数のサブクラスが必要になります。
• 高度なクラス機能はオプションです。

「viscera」の変化と比較したオブジェクトの「skin」の変化

前のセクションでは、図16–2に示すように、各デコレータノードの内部組み込みコンポーネントを使用して、実行時にさまざまなデコレータを接続する方法について説明しました。 また、ここでは、各デコレータが外部から組み込みコンポーネントを変更する、つまり、単にオブジェクトのシェルを変更することも示しています。 アイデアは、ノードがそれを変更しているものを知らないということです。

ただし、各ノードが他のノードを認識すると、チェーンは異なる方向、つまり内側から構築されます。 このパターンは戦略と呼ばれます（第19章を参照）。 戦略の別のノードに接続するには、各ノードに異なるAPIのセットを含める必要があります。 この概念の視覚的表現を図16-3に示します。



図16-3。 戦略パターンを使用してオブジェクトの「内部」を変更する

表16-1に、オブジェクトの「スキン」（装飾）と「内部」（戦略）の変更の最終的な違いを示します。

表16–1。 デコレータと戦略の違いの概要表

「スキン」の変更（装飾）	「インサイド」の変化（戦略）
外の変化	内部変更
個々のノードは変更を認識しません。	単一のノードは、事前定義された変更オプションを認識しています。

UIImageイメージのフィルターの作成

画像フィルタリングは、色やジオメトリなどの画像の属性を変更できるプロセスです。 画像の色相を変更できるフィルター、または焦点が合っていないように見えるように暗くするガウスフィルターを使用できます。 何らかの2D変換を適用して、表面が平らに見えないようにすることもできます。 画像にいくつかの「特殊効果」を適用するために使用できる多くの種類のフィルターがあります。 PhotoshopやGIMPなどの多くの写真エディターには、多くのフィルターが付属しています。 Decoratorパターンを使用した画像フィルターは最初に何をしますか？

デコレータパターン-既存の動作とインターフェイスを変更せずにオブジェクトに新しい動作を追加するこの方法。 画像オブジェクトには、属性を管理するためのインターフェースのみが含まれ、それ以上何も含まれないとしましょう。 変換フィルターなど、通常とは異なる何かを追加したいのですが、画像オブジェクトが既に持っている既存のインターフェースを変更したくありません。 できることは、画像オブジェクトと同じですが、動作を拡張する必要がある別の画像オブジェクトへのリンクを含む別のクラスを定義することです。 新しいクラスには、グラフィカルコンテキストで自身を描画するためのメソッドが含まれています。 彼の描画方法では、含まれている画像リンクに変換アルゴリズムを適用し、全体像を描画し、結果の画像を返します。 このプロセスは、写真の上に別のガラス層を適用することで説明できます。 画像はガラスについて何も知る必要はありません、そして私たちがそれを見るとき、私たちはまだそれを絵と考えます。 ガラス自体は、画像の外観が異なるように、何らかの色、表面の波状構造などを持っている場合があります。 後で別のレイヤーまたはフィルターを画像に適用する場合は、変換の場合と同じように別のフィルタークラスを定義して、同じメカニズムを適用して画像を変更できます。 変換後の他のフィルターは、結果の画像を取得してプロセスを続行できます。 ただし、注意すべき重要な点が1つあります。フィルターチェーンを介して送信される画像は常にオリジナルである必要はありませんが、同じタイプである必要があります。 変換フィルターの後に返される画像は、変換された画像です。 その後、カラーフィルターに転送されると、返される画像は色が変わり、変換されます。

Cocoa TouchフレームワークのUIKitのUIImageは、画像オブジェクトを表します。 UIImageクラスUIImageは、画像を操作するためのかなり限られたインターフェースがあります。 サイズ、色などのいくつかの画像プロパティだけがあります。Quartz2Dフレームワークで利用可能な機能のいくつかで通常の画像オブジェクトを拡張します。 パターンを実装するには、サブクラスとカテゴリの2つのアプローチがあります。

サブクラスを介したデコレーターの実装

サブクラスベースのアプローチの場合、構造は図16–1に示す元のパターンスタイルに似ています。 唯一の違いは、要素の最終的なタイプがUIImageカテゴリであり、サブクラスではないことです。 UIImage実装するのと同じインターフェースを共有UIImageことをUIImage構造上の問題が1つあります。 UIImageはNSObject直接の子孫であり、それ以上のものではありません。 これは一種の最終クラスです。 UIImageクラスとフィルタクラスの両方を結合するために、「 Component 」インターフェイス（図16–1のクラス図の親インターフェイスとして）を使用するには、回避策が必要です。 現在、2つの問題があります。

• フィルタークラスをUImageと同じにする必要がありますが、 UIImageは共有分離のための高レベルインターフェイスはありません（ UIImageからのUIImageはここでは想定されていません）。
• UIImageはdrawAsPatternInRect: drawAtPoint: drawAtPoint:blendMode:alpha: drawAtPoint: drawAtPoint:blendMode:alpha: drawInRect: 、 drawInRect:blendMode:alpha:など、現在のコンテキストのコンテンツの描画に関連するいくつかのメソッドがありdrawInRect:blendMode:alpha: フィルタークラスで同じメソッドを実装できるようにすると、すべてが複雑になり、Quartz 2Dの動作に応じた結果が得られない場合があります。 これについては後で説明します。

私たちは何をするつもりですか？ もちろん、まず、このパターンが機能し、両方のタイプのクラスが同じ基本タイプを共有できるように、フィルターUIImageのグループでUIImageを分離するためのインターフェイスが必要です。 この目的のためにUIImageを高レベルの型として使用する（つまり、継承する）という考えは、フィルターを使用するのが困難になるため、悪い考えです。 誰にとっても最適な基本型として、プロトコルの形式でImageComponentインターフェースを作成します。 しかし、ちょっと待ってください。 UIImageはどのインターフェイスからも継承せず、単にNSObject直接継承することは言及しませんでしたか？ はい、そうです-ここがクリエイティブなソリューションを必要とする場所です。 UIImageを実装するUIImageカテゴリーを作成します。 コンパイラーは、 UIImageとImageComponentが相対的であることをUIImage 、誓うことはありません。 UIImageは、新しいベースタイプを持つことに気づきさえしません。 フィルターを使用する人だけがこれについて知る必要があります。

また、 UIImageで定義された元のdraw*メソッドを台無しにするつもりはありませんが、別のImageComponent描画オプションをどのように拡張しますか？ すぐにこれに到達します。

図16-4に、それらの関係を示すクラス図を示します。



図16-4。 Decoratorパターンを実装するさまざまな画像フィルターのクラス図

ImageComponentプロトコルは、 UIImageクラスのすべてのdraw*メソッドで抽象インターフェースを定義します。 特定のImageComponentおよび同様のデコレータは、これらの呼び出しを処理できる必要があります。 UIImageインスタンスのdraw*メッセージにより、現在のグラフィックスコンテキストでコンテンツを描画できます。 各メソッドは、このコンテキストで変換やその他の効果を作成することもできます。 したがって、 draw*操作の前に独自のフィルタリングを実装できます。

ここでの特定のコンポーネントはUIImageタイプですが、ゲームの一部にするためだけにサブクラス化する必要はないため、カテゴリを定義します。 UIImage (ImageComponent)は、 ImageComponentプロトコルを実装します。 プロトコルで宣言されたすべてのメソッドはすでにUIImageクラスにあるため、それらをカテゴリに実装する必要はありません。 このカテゴリは基本的に何も行いませんが、コンパイラにImageComponent一種でもあることを伝えるだけImageComponent 。

ImageFilterは、図16–1のDecoratorクラスに似ています。 ImageFilterクラスのapplyメソッドを使用すると、特定のフィルタークラスがベースcomponent_追加の動作を追加できcomponent_ 。 すべてのdraw*メソッドをオーバーライドしてフィルターアクションを実装する代わりに、単一の(id) forwardingTargetForSelector:(SEL)aSelectorを使用してそれらすべてを処理します。 forwardingTargetForSelector: NSObjectクラスで定義されます。これにより、サブクラスは代替受信者を返してaSelectorセレクターを呼び出すことがaSelectorます。 ImageFilterインスタンスImageFilter 、 aSelector draw*メッセージの一部であるかどうかImageFilter最初にチェックします。 その場合、彼は自分自身にapplyメッセージを送信して、追加の動作を導入してから、 component_を返してデフォルトのアクションを呼び出します。 applyメソッドのデフォルト実装は何もしません。 不足している情報はサブクラスによって提供される必要があります。 この方法は、各フィルタークラスが動作を拡張するための同じメカニズムを実装する場合よりもはるかに簡単です。

ImageTransformFilterとImageShadowFilterどちらも、 applyメソッドをオーバーライドして独自のフィルタリングアルゴリズムを提供することに重点を置いていapply 。 これらは、プライベート変数component_として別のImageComponentへのリンクを持つImageFilter基本クラスから継承しcomponent_ 。 図16-5に示すように、実行時にさまざまなImageComponentオブジェクトを接続できます。



図16-5。 各ImageComponentが各レベルのImageComponentの異なるインスタンスで参照されていることを示すオブジェクト図。

このチェーンの右端は元の画像で、図16-6の左側に示されています。 これをanImageTransformFilterに追加してからanImageTransformFilterをanImageTransformFilterに追加すると、クライアントは図16-6の右図のようになります。 各ノードはcomponent_別のImageComponentインスタンスのcomponent_としてカプセル化されます。 大きな魚が小さな魚を飲み込む方法との類似性を描くことができます。 明らかに、クライアントはデコレータの詳細を知りませんが、同じ古いUIImageタイプのインスタンスへのリンクを受け取ります（ ImageComponentはカテゴリを介してUIImage実装するため、 ImageComponentの形式で）。



図16-6。 一連のフィルターを適用した後の元の画像と同じ画像

エキサイティングです。 コードで書き留める方法を見てみましょう。 最初に確認するのは、リスト16-1のプロトコルとして宣言されているImageComponentです。

リスト16–1。 ImageComponent.h

 @protocol ImageComponent <NSObject> //     //  UIImage   //   @optional - (void) drawAsPatternInRect:(CGRect)rect; - (void) drawAtPoint:(CGPoint)point; - (void) drawAtPoint:(CGPoint)point blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alpha; - (void) drawInRect:(CGRect)rect; - (void) drawInRect:(CGRect)rect blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alpha; @end 

各ImageComponentこれらの操作をサポートできるようにするため、すべてのdraw*メソッドは@optionalとして宣言されますが、実装クラスで実際に再定義することはありません。 @optionalは、適切なメソッド実装が利用できない可能性があることをコンパイラに通知します。

リスト16–2にはUIImageカテゴリ宣言が含まれており、後で他のデコレータで使用できます。

リスト16–2。 UIImage + ImageComponent.h

 #import "ImageComponent.h" @interface UIImage (ImageComponent) <ImageComponent> @end 

彼女（カテゴリ）は、実際の実装なしでImageComponentプロトコルを実装します。 ここで、メインのデコレータークラスであるImageFilterます。 彼の広告はリスト16–3に示されています。

リスト16-3。 ImageFilter.h

 #import "ImageComponent.h" #import "UIImage+ImageComponent.h" @interface ImageFilter : NSObject <ImageComponent> { @private id <ImageComponent> component_; } @property (nonatomic, retain) id <ImageComponent> component; - (void) apply; - (id) initWithImageComponent:(id <ImageComponent>) component; - (id) forwardingTargetForSelector:(SEL)aSelector; @end 

component_の形式でImageComponentへのリンクが含まれており、他の特定のデコレーターを使用してデコードできます。 ImageFilter forwardingTargetForSelector:をオーバーライドし、 applyを宣言しapply 。 クラスの実装をリスト16–4に示します。

リスト16-4。 ImageFilter.m

 #import "ImageFilter.h" @implementation ImageFilter @synthesize component=component_; - (id) initWithImageComponent:(id <ImageComponent>) component { if (self = [super init]) { //  ImageComponent [self setComponent:component]; } return self; } - (void) apply { //     //     } - (id) forwardingTargetForSelector:(SEL)aSelector { NSString *selectorName = NSStringFromSelector(aSelector); if ([selectorName hasPrefix:@"draw"]) { [self apply]; } return component_; } @end 

initWithImageComponent:メソッドはそれほど多くありません。 メソッドパラメータ自体からImageComponentへのリンクを割り当てるだけです。 また、この場合、特定のフィルタークラスで再度表示されるまで、彼のapplyメソッドは何もしません。

ここで興味深いのは、 forwardingTargetForSelector:を使用して、 ImageFilterインスタンスImageFilter処理方法を知らないメッセージへの呼び出しをインターセプトすることです。 このメソッドにより、サブクラスは別のメッセージ受信者をランタイムに渡し、元のメッセージがリダイレクトされるようにします。 しかし、 @“draw”プレフィックスを持つすべてのものにのみ関心があり、それ以外のすべてのものを直接component_リダイレクトして、ランタイムに返します。 たとえば、 drawAtRect:メッセージdrawAtRect: ImageFilterインスタンスに送信されると、そのメッセージdrawAtRect: forwardingTargetForSelector:メソッドでインターセプトされ、 ImageFilterには実装されていないため、代替受信者を待機します。 メッセージには「draw」プレフィックスが含まれているため、このメソッドはapplyメッセージを送信して、 component_後でメッセージを処理する前に何かを実行します。

これで、実際のフィルターを取得できます。 リスト16-5に示すように、最初に作成するのはImageTransformFilterです。

リスト16-5。 ImageTransformFilter.h

 #import "ImageFilter.h" @interface ImageTransformFilter : ImageFilter { @private CGAffineTransform transform_; } @property (nonatomic, assign) CGAffineTransform transform; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform; - (void) apply; @end 

ImageTransformFilterはImageFilterサブクラスであり、 applyメソッドをオーバーライドしapply 。 また、 CGAffineTransform型のprivate transform_変数とそれに関連するプロパティを宣言してアクセスします。 CGAffineTransformはC構造体であるため、その値は他のObjective-Cオブジェクトのようにretainと呼ばれないため、プロパティは割り当て可能な型である必要があります。 フィルターには独自の初期化メソッドがあります。 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . . initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

 initWithImageComponent:(id )component transform: (CGAffineTransform)tranform   ImageComponent   CGAffineTransform   . component    initWithComponent:   super ,  transform    ,     16–6. 
 
  16–6. ImageTransformFilter.m 
 @implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGContextConcatCTM(context, transform_); } @end 
 
   apply    CGContextRef   Quartz 2D UIGraphicsGetCurrentContext() .       Quartz 2D .        ,    transform_  CGContextConcatCTM()     .        ,        CGAffineTransform .     . 
 
   ImageTransformFilter , ImageShadowFilter      ImageFilter     apply .  ,    16–7,    ,    Quartz 2D CGContextSetShadow() ,   .     ,    ImageTransformFilter . ,    ,     ,        16–6. 
 
  16–7. ImageShadowFilter.m 
 #import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end 
 
           .  -      DecoratorViewController ,         viewDidLoad ,     16–8. 
 
  16–8.  viewDidLoad  DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,    id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; //   DecoratorView //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
        ,      16–6.   CGAffineTransform      .  ,       ImageTransformFilter   .     ,    ImageShadowFilter ,     ,   ImageTransformFilter .    finalImage –   ,   ImageTransformFilter , ImageShadowFilter   .       DecoratorView  ,        subview . DecoratorView  ,       drawRect:rect ,     16–9. 
 
  16–9.  drawRect:rect  DecoratorView.m 
 - (void)drawRect:(CGRect)rect { //  . [image_ drawInRect:rect]; } 
 
 DecoratorView      UIImage   image_ .  drawRect:rect   drawInRect:rect  image_   rect .        . ImageShadowFilter   .  ,           component_   forwardingTargetForSelector: ,        component_   .    component_ -    ImageTransformFilter ,       .     forwardingTargetForSelector:         CGAffineTransform .     component_  ,   ImageShadowFilter .        ,      ImageTransformFilter      ,     ,        .    ,        ,     16–6. 
 
 :       . 
 
      ,  ,       .   ,   . 
 
      
  ,  ,        UIImage   ,         UIImage ,      .        Objective-C.     ,  -   2D-  ,  –   .  ,    ,    16–7. 
 
  
 
  16–7.     ,    UIImage 
 
     ,      .         - UIImage (BaseFilter) , UIImage (Transform)  UIImage (Shadow) .       BaseFilter , Transform  Shadow . BaseFilter    2D  ,        ,     ImageFilter   .              .  Transform ,  Shadow    BaseFilter ,     ,      –  UIImage . ,   BaseFilter ,       Transform  Shadow ,     ,   .  Transform   imageWithTransform:transform ,      (   ),    ,    ,     .  Shadow   imageWithDropShadow ,               . ,   ,        ,   ,    .  ,   ,    16–8. 
 
  
 
  16–8.   ,   -     UIImage    
 
    –   ,  ,     16–6.       Shadow     Transform , ,     ,  -    16–6.        ,   ,     self           component_ . 
 
    .     BaseFilter ,   ,         ,     16–10. 
 
  16–10. UIImage+BaseFilter.h 
 @interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end 
 
 BaseFilter   ,       ,  16–11. 
 
  16–11. UIImage+BaseFilter.m 
 #import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { //       //  iOS 4    UIGraphicsBeginImageContextWithOptions //    //    iOS  UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; //  UIImage    UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end 
 
 beginContext –     ,     .      .     ,     . 
 
 getImageFromCurrentImageContext             UIGraphicsGetImageFromCurrentImageContext() . 
 
   endContext     Quartz 2D UIGraphicsEndImageContext()   - . 
 
        . ,    , -   Transform .  Transform    ,    CGAffineTransform     .      16–12. 
 
  16–12. UIImage+Transform.h 
 @interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end 
 
    ,     16–13. 
 
  16–13. UIImage+Transform.m 
 #import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; //   CGContextConcatCTM(context, transform); //      UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
    CGAffineTransform ,       .   transform     Quartz 2D, CGContextConcatCTM(context, transform) .  transform     .    self  getImageFromCurrentImageContext ,     BaseFilter    .  ,   UIImage   ,   endContext      ,   ,  . 
 
      Transform .  ,   ?      Shadow   ,   ,     16–14. 
 
  16–14. UIImage+Shadow.h 
 @interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end 
 
  ,    Transform , Shadow –    UIImage ,   .    ,       ,    Transform .   ,        16–15. 
 
  16–15. UIImage+Shadow.m 
 #import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; //   CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); //      UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end 
 
      ,   ,     Quartz 2D, CGSizeMake (-25, 15) ,        X  Y.       CGContextSetShadow(context, offset, 20.0) ,   Quartz 2D,   20.0,    .  ,     addTranform:  Transform ,    ,  UIImag e   . 
 
            UIImag e.     ?      viewDidLoad  DecoratorViewController ,     16–16. 
 
  16–16.  viewDidLoad   DecoratorViewController.m 
 - (void)viewDidLoad { [super viewDidLoad]; //    UIImage *image = [UIImage imageNamed:@"Image.png"]; //   CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // ,   //   UIImage *transformedImage = [image imageWithTransform:finalTransform]; //   id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; //   image view //    DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; } 
 
    ,      ,     16–8   .   ,  imageWithTransform: ,     ,         (  ).       imageWithDropShadow ,     ,            finalImage . finalImage    imageView    ,     .      : 
 
 finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow]; 
    ,     ,  ,   ?  –  UIImage    –   ,    ,    .     ,   ,     –   UIImage !   ImageComponent          ,    UIImage      .          . 
 
       .  ,           UIImage    .               . 
 
  Objective-C    
 
  –    Objective-C,     (   )    .           .         . 
 
      ,       .      ;    ,    . ,   , -    ,  Objective-C    (     )     .           . 
 
    ,            ,          ,    .   UIImag e        ,       self  UIImage . 
 
  
              Objective-C.            . ,   ,    ,   .    ,         .            ,     .   –          .                 UIImage . 
 
      ,   ,    .    . 

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .

initWithImageComponent:(id )component transform: (CGAffineTransform)tranform ImageComponent CGAffineTransform . component initWithComponent: super , transform , 16–6.

16–6. ImageTransformFilter.m
@implementation ImageTransformFilter @synthesize transform=transform_; - (id) initWithImageComponent:(id <ImageComponent>)component transform:(CGAffineTransform)transform { if (self = [super initWithImageComponent:component]) { [self setTransform:transform]; } return self; } - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGContextConcatCTM(context, transform_); } @end

apply CGContextRef Quartz 2D UIGraphicsGetCurrentContext() . Quartz 2D . , transform_ CGContextConcatCTM() . , CGAffineTransform . .

ImageTransformFilter , ImageShadowFilter ImageFilter apply . , 16–7, , Quartz 2D CGContextSetShadow() , . , ImageTransformFilter . , , , 16–6.

16–7. ImageShadowFilter.m
#import "ImageShadowFilter.h" @implementation ImageShadowFilter - (void) apply { CGContextRef context = UIGraphicsGetCurrentContext(); // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); } @end

. - DecoratorViewController , viewDidLoad , 16–8.

16–8. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , id <ImageComponent> transformedImage = [[[ImageTransformFilter alloc] initWithImageComponent:image transform:finalTransform] autorelease]; id <ImageComponent> finalImage = [[[ImageShadowFilter alloc] initWithImageComponent:transformedImage] autorelease]; // DecoratorView // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, 16–6. CGAffineTransform . , ImageTransformFilter . , ImageShadowFilter , , ImageTransformFilter . finalImage – , ImageTransformFilter , ImageShadowFilter . DecoratorView , subview . DecoratorView , drawRect:rect , 16–9.

16–9. drawRect:rect DecoratorView.m
- (void)drawRect:(CGRect)rect { // . [image_ drawInRect:rect]; }

DecoratorView UIImage image_ . drawRect:rect drawInRect:rect image_ rect . . ImageShadowFilter . , component_ forwardingTargetForSelector: , component_ . component_ - ImageTransformFilter , . forwardingTargetForSelector: CGAffineTransform . component_ , ImageShadowFilter . , ImageTransformFilter , , . , , 16–6.

: .

, , . , .


, , UIImage , UIImage , . Objective-C. , - 2D- , – . , , 16–7.



16–7. , UIImage

, . - UIImage (BaseFilter) , UIImage (Transform) UIImage (Shadow) . BaseFilter , Transform Shadow . BaseFilter 2D , , ImageFilter . . Transform , Shadow BaseFilter , , – UIImage . , BaseFilter , Transform Shadow , , . Transform imageWithTransform:transform , ( ), , , . Shadow imageWithDropShadow , . , , , , . , , 16–8.



16–8. , - UIImage

– , , 16–6. Shadow Transform , , , - 16–6. , , self component_ .

. BaseFilter , , , 16–10.

16–10. UIImage+BaseFilter.h
@interface UIImage (BaseFilter) - (CGContextRef) beginContext; - (UIImage *) getImageFromCurrentImageContext; - (void) endContext; @end

BaseFilter , , 16–11.

16–11. UIImage+BaseFilter.m
#import "UIImage+BaseFilter.h" @implementation UIImage (BaseFilter) - (CGContextRef) beginContext { // // iOS 4 UIGraphicsBeginImageContextWithOptions // // iOS UIGraphicsBeginImageContext CGSize size = [self size]; if (NULL != UIGraphicsBeginImageContextWithOptions) UIGraphicsBeginImageContextWithOptions(size, NO, 0); else UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); return context; } - (UIImage *) getImageFromCurrentImageContext { [self drawAtPoint:CGPointZero]; // UIImage UIImage *imageOut = UIGraphicsGetImageFromCurrentImageContext(); return imageOut; } - (void) endContext { UIGraphicsEndImageContext(); } @end

beginContext – , . . , .

getImageFromCurrentImageContext UIGraphicsGetImageFromCurrentImageContext() .

endContext Quartz 2D UIGraphicsEndImageContext() - .

. , , - Transform . Transform , CGAffineTransform . 16–12.

16–12. UIImage+Transform.h
@interface UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform; @end

, 16–13.

16–13. UIImage+Transform.m
#import "UIImage+Transform.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Transform) - (UIImage *) imageWithTransform:(CGAffineTransform)transform { CGContextRef context = [self beginContext]; // CGContextConcatCTM(context, transform); // UIImage *imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

CGAffineTransform , . transform Quartz 2D, CGContextConcatCTM(context, transform) . transform . self getImageFromCurrentImageContext , BaseFilter . , UIImage , endContext , , .

Transform . , ? Shadow , , 16–14.

16–14. UIImage+Shadow.h
@interface UIImage (Shadow) - (UIImage *) imageWithDropShadow; @end

, Transform , Shadow – UIImage , . , , Transform . , 16–15.

16–15. UIImage+Shadow.m
#import "UIImage+Shadow.h" #import "UIImage+BaseFilter.h" @implementation UIImage (Shadow) - (UIImage *) imageWithDropShadow { CGContextRef context = [self beginContext]; // CGSize offset = CGSizeMake (-25, 15); CGContextSetShadow(context, offset, 20.0); // UIImage * imageOut = [self getImageFromCurrentImageContext]; [self endContext]; return imageOut; } @end

, , Quartz 2D, CGSizeMake (-25, 15) , X Y. CGContextSetShadow(context, offset, 20.0) , Quartz 2D, 20.0, . , addTranform: Transform , , UIImag e .

UIImag e. ? viewDidLoad DecoratorViewController , 16–16.

16–16. viewDidLoad DecoratorViewController.m
- (void)viewDidLoad { [super viewDidLoad]; // UIImage *image = [UIImage imageNamed:@"Image.png"]; // CGAffineTransform rotateTransform = CGAffineTransformMakeRotation(-M_PI / 4.0); CGAffineTransform translateTransform = CGAffineTransformMakeTranslation( -image.size.width / 2.0, image.size.height / 8.0); CGAffineTransform finalTransform = CGAffineTransformConcat(rotateTransform, translateTransform); // , // UIImage *transformedImage = [image imageWithTransform:finalTransform]; // id <ImageComponent> finalImage = [transformedImage imageWithDropShadow]; // image view // DecoratorView *decoratorView = [[[DecoratorView alloc] initWithFrame:[self.view bounds]] autorelease]; [decoratorView setImage:finalImage]; [self.view addSubview:decoratorView]; }

, , 16–8 . , imageWithTransform: , , ( ). imageWithDropShadow , , finalImage . finalImage imageView , . :

finalImage = [[image imageWithTransform:finalTransform] imageWithDropShadow];
, , , ? – UIImage – , , . , , – UIImage ! ImageComponent , UIImage . .

. , UIImage . .

Objective-C

– Objective-C, ( ) . . .

, . ; , . , , - , Objective-C ( ) . .

, , , . UIImag e , self UIImage .


Objective-C. . , , , . , . , . – . UIImage .

, , . .