react-native-macos/RNTester/RCTTest/FBSnapshotTestCase/UIImage+Diff.m

34 строки
1.2 KiB
Objective-C

/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
#import "UIImage+Diff.h"
@implementation UIImage (Diff)
- (UIImage *)diffWithImage:(UIImage *)image
{
if (!image) {
return nil;
}
CGSize imageSize = CGSizeMake(MAX(self.size.width, image.size.width), MAX(self.size.height, image.size.height));
UIGraphicsBeginImageContextWithOptions(imageSize, YES, 0.0);
CGContextRef context = UIGraphicsGetCurrentContext();
[self drawInRect:CGRectMake(0, 0, self.size.width, self.size.height)];
CGContextSetAlpha(context, 0.5f);
CGContextBeginTransparencyLayer(context, NULL);
[image drawInRect:CGRectMake(0, 0, image.size.width, image.size.height)];
CGContextSetBlendMode(context, kCGBlendModeDifference);
CGContextSetFillColorWithColor(context,[UIColor whiteColor].CGColor);
CGContextFillRect(context, CGRectMake(0, 0, self.size.width, self.size.height));
CGContextEndTransparencyLayer(context);
UIImage *returnImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return returnImage;
}
@end