Fully fledged flip implementation

Objective-C/TOCropViewController/Categories/UIImage+CropRotate.h

@@ -29,9 +29,11 @@ NS_ASSUME_NONNULL_BEGIN
 /// Crops a portion of an existing image object and returns it as a new image
 /// @param frame The region inside the image (In image pixel space) to crop
 /// @param angle If any, the angle the image is rotated at as well
+/// @param flip Whether to flip (mirror) the image
 /// @param circular Whether the resulting image is returned as a square or a circle
 - (nonnull UIImage *)croppedImageWithFrame:(CGRect)frame
                                      angle:(NSInteger)angle
+                                      flip:(BOOL)flip
                               circularClip:(BOOL)circular;
 
 @end

Objective-C/TOCropViewController/Categories/UIImage+CropRotate.m

@@ -31,7 +31,7 @@ - (BOOL)hasAlpha
             alphaInfo == kCGImageAlphaPremultipliedFirst || alphaInfo == kCGImageAlphaPremultipliedLast);
 }
 
-- (UIImage *)croppedImageWithFrame:(CGRect)frame angle:(NSInteger)angle circularClip:(BOOL)circular
+- (UIImage *)croppedImageWithFrame:(CGRect)frame angle:(NSInteger)angle flip:(BOOL)flip circularClip:(BOOL)circular
 {
     UIGraphicsImageRendererFormat *format = [UIGraphicsImageRendererFormat new];
     format.opaque = !self.hasAlpha && !circular;
@@ -46,14 +46,18 @@ - (UIImage *)croppedImageWithFrame:(CGRect)frame angle:(NSInteger)angle circular
             CGContextAddEllipseInRect(context, (CGRect){CGPointZero, frame.size});
             CGContextClip(context);
         }
+
+        // Flip image when applicable
+        CGContextTranslateCTM(context, flip ? frame.size.width : 0,  0);
+        CGContextScaleCTM(context, flip ? -1 : 1, 1);
 
         // Offset the origin (Which is the top left corner) to start where our cropping origin is
         CGContextTranslateCTM(context, -frame.origin.x, -frame.origin.y);
 
         // If an angle was supplied, rotate the entire canvas + coordinate space to match
         if (angle != 0) {
             // Rotation in radians
-            CGFloat rotation = angle * (M_PI/180.0f);
+            CGFloat rotation = angle * (M_PI/180.0);
 
             // Work out the new bounding size of the canvas after rotation
             CGRect imageBounds = (CGRect){CGPointZero, self.size};

Objective-C/TOCropViewController/Categories/UIView+Pixels.h

@@ -0,0 +1,41 @@
+//
+//  UIView+Pixels.h
+//
+//  Copyright 2024 Jan de Vries. All rights reserved.
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to
+//  deal in the Software without restriction, including without limitation the
+//  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+//  sell copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in
+//  all copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+//  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+//  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+//  IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+#import <UIKit/UIKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface UIView(TOPixels)
+
+///Round point value to nearest physical pixel
+- (CGFloat)roundToNearestPixel:(CGFloat)point NS_SWIFT_NAME(roundToNearestPixel(point:));
+
+///Check if two CGFloats (points) round to the same number of physical pixels
+- (BOOL)pixelCountOf:(CGFloat)point1 equals:(CGFloat)point2;
+
+///Works like CGRectIntegral() but rounds values to the nearest physical pixel
+- (CGRect)CGRectIntegralRetina:(CGRect)rect;
+
+@end
+
+NS_ASSUME_NONNULL_END
+

Objective-C/TOCropViewController/Categories/UIView+Pixels.m

@@ -0,0 +1,52 @@
+//
+//  UIView+Pixels.m
+//
+//  Copyright 2024 Jan de Vries. All rights reserved.
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to
+//  deal in the Software without restriction, including without limitation the
+//  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+//  sell copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in
+//  all copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+//  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+//  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+//  IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+#import "UIView+Pixels.h"
+
+@implementation UIView (TOPixels)
+
+- (CGFloat)roundToNearestPixel:(CGFloat)point {
+    CGFloat screenScale = 2.0;
+    if (self.window != nil && self.window.screen != nil) {
+        screenScale = self.window.screen.scale;
+    }
+    return round(point * screenScale) / screenScale;
+}
+
+- (BOOL)pixelCountOf:(CGFloat)point1 equals:(CGFloat)point2
+{
+    if (self.window == nil || self.window.screen == nil) {
+        return point1 == point2;
+    }
+    CGFloat screenScale = self.window.screen.scale;
+    return round(point1*screenScale) == round(point2*screenScale);
+}
+
+- (CGRect)CGRectIntegralRetina:(CGRect)rect
+{
+    return CGRectMake([self roundToNearestPixel:rect.origin.x],
+                      [self roundToNearestPixel:rect.origin.y],
+                      [self roundToNearestPixel:rect.size.width],
+                      [self roundToNearestPixel:rect.size.height]);
+}
+
+@end

Objective-C/TOCropViewController/Models/TOActivityCroppedImageProvider.h

@@ -29,9 +29,10 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonnull, nonatomic, readonly) UIImage *image;
 @property (nonatomic, readonly) CGRect cropFrame;
 @property (nonatomic, readonly) NSInteger angle;
+@property (nonatomic, readonly) BOOL flipped;
 @property (nonatomic, readonly) BOOL circular;
 
-- (nonnull instancetype)initWithImage:(nonnull UIImage *)image cropFrame:(CGRect)cropFrame angle:(NSInteger)angle circular:(BOOL)circular;
+- (nonnull instancetype)initWithImage:(nonnull UIImage *)image cropFrame:(CGRect)cropFrame angle:(NSInteger)angle flipped:(BOOL)flipped circular:(BOOL)circular;
 
 @end
 

Objective-C/TOCropViewController/Models/TOActivityCroppedImageProvider.m

@@ -28,6 +28,7 @@ @interface TOActivityCroppedImageProvider ()
 @property (nonatomic, strong, readwrite) UIImage *image;
 @property (nonatomic, assign, readwrite) CGRect cropFrame;
 @property (nonatomic, assign, readwrite) NSInteger angle;
+@property (nonatomic, assign, readwrite) BOOL flipped;
 @property (nonatomic, assign, readwrite) BOOL circular;
 
 @property (atomic, strong) UIImage *croppedImage;
@@ -36,12 +37,13 @@ @interface TOActivityCroppedImageProvider ()
 
 @implementation TOActivityCroppedImageProvider
 
-- (instancetype)initWithImage:(UIImage *)image cropFrame:(CGRect)cropFrame angle:(NSInteger)angle circular:(BOOL)circular
+- (instancetype)initWithImage:(UIImage *)image cropFrame:(CGRect)cropFrame angle:(NSInteger)angle flipped:(BOOL)flipped circular:(BOOL)circular
 {
     if (self = [super initWithPlaceholderItem:[UIImage new]]) {
         _image = image;
         _cropFrame = cropFrame;
         _angle = angle;
+        _flipped = flipped;
         _circular = circular;
     }
 
@@ -63,12 +65,12 @@ - (id)activityViewController:(UIActivityViewController *)activityViewController
 - (id)item
 {
     //If the user didn't touch the image, just forward along the original
-    if (self.angle == 0 && CGRectEqualToRect(self.cropFrame, (CGRect){CGPointZero, self.image.size})) {
+    if (self.angle == 0 && !self.flipped && CGRectEqualToRect(self.cropFrame, (CGRect){CGPointZero, self.image.size})) {
         self.croppedImage = self.image;
         return self.croppedImage;
     }
 
-    UIImage *image = [self.image croppedImageWithFrame:self.cropFrame angle:self.angle circularClip:self.circular];
+    UIImage *image = [self.image croppedImageWithFrame:self.cropFrame angle:self.angle flip:self.flipped circularClip:self.circular];
     self.croppedImage = image;
     return self.croppedImage;
 }

Objective-C/TOCropViewController/Models/TOCropViewControllerTransitioning.m

@@ -27,7 +27,7 @@ @implementation TOCropViewControllerTransitioning
 
 - (NSTimeInterval)transitionDuration:(id <UIViewControllerContextTransitioning>)transitionContext
 {
-    return 0.45f;
+    return 0.45;
 }
 
 - (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionContext
@@ -86,21 +86,21 @@ - (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionC
         }
     }
 
-    cropViewController.view.alpha = (self.isDismissing ? 1.0f : 0.0f);
+    cropViewController.view.alpha = (self.isDismissing ? 1.0 : 0.0);
     if (imageView) {
-        [UIView animateWithDuration:[self transitionDuration:transitionContext] delay:0.0f usingSpringWithDamping:1.0f initialSpringVelocity:0.7f options:0 animations:^{
+        [UIView animateWithDuration:[self transitionDuration:transitionContext] delay:0.0 usingSpringWithDamping:1.0 initialSpringVelocity:0.7 options:0 animations:^{
             imageView.frame = self.toFrame;
         } completion:^(BOOL complete) {
-            [UIView animateWithDuration:0.25f animations:^{
-                imageView.alpha = 0.0f;
+            [UIView animateWithDuration:0.25 animations:^{
+                imageView.alpha = 0.0;
             }completion:^(BOOL complete) {
                 [imageView removeFromSuperview];
             }];
         }];
     }
 
     [UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
-        cropViewController.view.alpha = (self.isDismissing ? 0.0f : 1.0f);
+        cropViewController.view.alpha = (self.isDismissing ? 0.0 : 1.0);
     } completion:^(BOOL complete) {
         [self reset];
         [transitionContext completeTransition:![transitionContext transitionWasCancelled]];

Objective-C/TOCropViewController/Models/TOCroppedImageAttributes.h

@@ -28,10 +28,11 @@ NS_ASSUME_NONNULL_BEGIN
 @interface TOCroppedImageAttributes : NSObject
 
 @property (nonatomic, readonly) NSInteger angle;
+@property (nonatomic, readonly) BOOL flipped;
 @property (nonatomic, readonly) CGRect croppedFrame;
 @property (nonatomic, readonly) CGSize originalImageSize;
 
-- (instancetype)initWithCroppedFrame:(CGRect)croppedFrame angle:(NSInteger)angle originalImageSize:(CGSize)originalSize;
+- (instancetype)initWithCroppedFrame:(CGRect)croppedFrame angle:(NSInteger)angle flipped:(BOOL)flipped originalImageSize:(CGSize)originalSize;
 
 @end
 

Objective-C/TOCropViewController/Models/TOCroppedImageAttributes.m

@@ -25,17 +25,19 @@
 @interface TOCroppedImageAttributes ()
 
 @property (nonatomic, assign, readwrite) NSInteger angle;
+@property (nonatomic, assign, readwrite) BOOL flipped;
 @property (nonatomic, assign, readwrite) CGRect croppedFrame;
 @property (nonatomic, assign, readwrite) CGSize originalImageSize;
 
 @end
 
 @implementation TOCroppedImageAttributes
 
-- (instancetype)initWithCroppedFrame:(CGRect)croppedFrame angle:(NSInteger)angle originalImageSize:(CGSize)originalSize
+- (instancetype)initWithCroppedFrame:(CGRect)croppedFrame angle:(NSInteger)angle flipped:(BOOL)flipped originalImageSize:(CGSize)originalSize
 {
     if (self = [super init]) {
         _angle = angle;
+        _flipped = flipped;
         _croppedFrame = croppedFrame;
         _originalImageSize = originalSize;
     }