UIImage+Rotate.m

//
//  UIImage+Rotate.m
//  IphoneMapSdkDemo
//
//  Created by wzy on 14-11-14.
//  Copyright (c) 2014年 Baidu. All rights reserved.
//

#import "UIImage+Rotate.h"

@implementation UIImage (Rotate)

- (UIImage*)imageRotatedByDegrees:(CGFloat)degrees
{
    
    CGFloat width = CGImageGetWidth(self.CGImage);
    CGFloat height = CGImageGetHeight(self.CGImage);
    
    CGSize rotatedSize;
    
    rotatedSize.width = width;
    rotatedSize.height = height;
    
    UIGraphicsBeginImageContext(rotatedSize);
    CGContextRef bitmap = UIGraphicsGetCurrentContext();
    CGContextTranslateCTM(bitmap, rotatedSize.width/2, rotatedSize.height/2);
    CGContextRotateCTM(bitmap, degrees * M_PI / 180);
    CGContextRotateCTM(bitmap, M_PI);
    CGContextScaleCTM(bitmap, -1.0, 1.0);
    CGContextDrawImage(bitmap, CGRectMake(-rotatedSize.width/2, -rotatedSize.height/2, rotatedSize.width, rotatedSize.height), self.CGImage);
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return newImage;
}


@end