Shuffle & Cleanup Stuff (#3080)

Source/TextKit/ASTextKitShadower.h

@@ -0,0 +1,72 @@
+//
+//  ASTextKitShadower.h
+//  AsyncDisplayKit
+//
+//  Copyright (c) 2014-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+
+#import <UIKit/UIKit.h>
+#import <AsyncDisplayKit/ASBaseDefines.h>
+
+/**
+ * @abstract an immutable class for calculating shadow padding drawing a shadowed background for text
+ */
+AS_SUBCLASSING_RESTRICTED
+@interface ASTextKitShadower : NSObject
+
++ (ASTextKitShadower *)shadowerWithShadowOffset:(CGSize)shadowOffset
+                                    shadowColor:(UIColor *)shadowColor
+                                  shadowOpacity:(CGFloat)shadowOpacity
+                                   shadowRadius:(CGFloat)shadowRadius;
+
+/**
+ * @abstract The offset from the top-left corner at which the shadow starts.
+ * @discussion A positive width will move the shadow to the right.
+ *             A positive height will move the shadow downwards.
+ */
+@property (nonatomic, readonly, assign) CGSize shadowOffset;
+
+//! CGColor in which the shadow is drawn
+@property (nonatomic, readonly, strong) UIColor *shadowColor;
+
+//! Alpha of the shadow
+@property (nonatomic, readonly, assign) CGFloat shadowOpacity;
+
+//! Radius, in pixels
+@property (nonatomic, readonly, assign) CGFloat shadowRadius;
+
+/**
+ * @abstract The edge insets which represent shadow padding
+ * @discussion Each edge inset is less than or equal to zero.
+ *
+ * Example:
+ *  CGRect boundsWithoutShadowPadding; // Large enough to fit text, not large enough to fit the shadow as well
+ *  UIEdgeInsets shadowPadding = [shadower shadowPadding];
+ *  CGRect boundsWithShadowPadding = UIEdgeInsetsRect(boundsWithoutShadowPadding, shadowPadding);
+ */
+- (UIEdgeInsets)shadowPadding;
+
+- (CGSize)insetSizeWithConstrainedSize:(CGSize)constrainedSize;
+
+- (CGRect)insetRectWithConstrainedRect:(CGRect)constrainedRect;
+
+- (CGSize)outsetSizeWithInsetSize:(CGSize)insetSize;
+
+- (CGRect)outsetRectWithInsetRect:(CGRect)insetRect;
+
+- (CGRect)offsetRectWithInternalRect:(CGRect)internalRect;
+
+- (CGPoint)offsetPointWithInternalPoint:(CGPoint)internalPoint;
+
+- (CGPoint)offsetPointWithExternalPoint:(CGPoint)externalPoint;
+
+/**
+ * @abstract draws the shadow for text in the provided CGContext
+ * @discussion Call within the text node's +drawRect method
+ */
+- (void)setShadowInContext:(CGContextRef)context;
+
+@end