Help, Im new to ios programming, I want to rotate may UIImage but I dont want the edges to be cut or loose some part of the image.
this is my code:
double angle = M_PI * 10/ 180; CGSize s = {image.size.width, image.size.height}; UIGraphicsBeginImageContext(s); CGContextRef ctx = UIGraphicsGetCurrentContext();
CGAffineTransform transform = CGAffineTransformIdentity;
transform = CGAffineTransformTranslate(transform, image.size.width/2, image.size.height/2);
transform = CGAffineTransformRotate(transform, angle);
transform = CGAffineTransformScale(transform, 1.0, -1.0);
CGContextConcatCTM(ctx, transform);
CGContextDrawImage(ctx,CGRectMake(-[image size].width/2,-[image size].height/2,image.size.width, image.size.height),image.CGImage);
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(newImage, nil, nil, nil);
The image is rotating but the size of the frame does not change because of that some of the image has been cut.
EXPECTED OUTPUT: https://fbcdn-photos-g-a.akamaihd.net/hphotos-ak-xfa1/t1.0-0/10314770_761675840521898_6536715783383115855_a.jpg
Please help me thank you.
This might be what you are searching for.
Just copy the following code at the end of the .m
file (after the @end
) in which you want to rotate an image.
@interface UIImage (RotationMethods)
- (UIImage *)imageRotatedByDegrees:(CGFloat)degrees;
@end
@implementation UIImage (RotationMethods)
static CGFloat DegreesToRadians(CGFloat degrees) {return degrees * M_PI / 180;};
- (UIImage *)imageRotatedByDegrees:(CGFloat)degrees
{
// calculate the size of the rotated view's containing box for our drawing space
UIView *rotatedViewBox = [[UIView alloc] initWithFrame:CGRectMake(0,0,self.size.width, self.size.height)];
CGAffineTransform t = CGAffineTransformMakeRotation(DegreesToRadians(degrees));
rotatedViewBox.transform = t;
CGSize rotatedSize = rotatedViewBox.frame.size;
// Create the bitmap context
UIGraphicsBeginImageContext(rotatedSize);
CGContextRef bitmap = UIGraphicsGetCurrentContext();
// Move the origin to the middle of the image so we will rotate and scale around the center.
CGContextTranslateCTM(bitmap, rotatedSize.width/2, rotatedSize.height/2);
// // Rotate the image context
CGContextRotateCTM(bitmap, DegreesToRadians(degrees));
// Now, draw the rotated/scaled image into the context
CGContextScaleCTM(bitmap, 1.0, -1.0);
CGContextDrawImage(bitmap, CGRectMake(-self.size.width / 2, -self.size.height / 2, self.size.width, self.size.height), [self CGImage]);
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
Then rotate your image like in the example below:
CGFloat degrees = 90;
yourImage = [yourImage imageRotatedByDegrees:degrees];