iOS Question How to rotate bitmap

chjk said:

This rotate bitmap b4i code

B4X:

Sub RotateImageByDegrees(original As Bitmap, degree As Float) As Bitmap
    original= nome.RunMethod("imageRotatedByDegrees::", Array(original,degree))
  Return original
End Sub

Sub RotateImageByRadians(original As Bitmap, radians As Float) As Bitmap
    original= nome.RunMethod("imageRotatedByRadians::", Array(original,radians))
  Return original
End Sub
#If OBJC
CGFloat DegreesToRadians(CGFloat degrees) {return degrees * M_PI / 180;};
CGFloat RadiansToDegrees(CGFloat radians) {return radians * 180/M_PI;};
- (UIImage *)imageRotatedByRadians:(UIImage *)bmp:(CGFloat)radians
{
   return [self imageRotatedByDegrees:bmp:RadiansToDegrees(radians)];
}
- (UIImage *)imageRotatedByDegrees:(UIImage *)bmp:(CGFloat)degrees
{
   // calculate the size of the rotated view's containing box for our drawing space
   UIView *rotatedViewBox = [[UIView alloc] initWithFrame:CGRectMake(0,0,bmp.size.width, bmp.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(-bmp.size.width / 2, -bmp.size.height / 2, bmp.size.width, bmp.size.height), bmp.CGImage);

   UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
   UIGraphicsEndImageContext();
   return newImage;
}
#End If

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