UIImage Image resize (이미지 비율)

//이미지의 사이즈를 resize하는데 비율대로 가로와 세로를 재구성한다.

+(UIImage*)imageWithImage: (UIImage*) sourceImage scaledResize: (float) size

{

//size == 1080

    BOOL isWidthLong = NO;

    //이미지가 가로가 더 큰 이미지

    if (sourceImage.size.width > sourceImage.size.height)

    {

        if (sourceImage.size.width <= size) return sourceImage;//가로가 큰데 1080보다 작거나 같다면 사이즈 조절할 필요가없음.

        isWidthLong = YES;

    }

    else

    {

        if (sourceImage.size.height <= size) return sourceImage;//세로가 큰데 1080보다 작거나 같다면 사이즈 조절 X

        isWidthLong = NO;

    }

    

    if (isWidthLong)//가로가 크다면

    {

        float oldWidth = sourceImage.size.width;

        float scaleFactor = size / oldWidth;

        

        float newHeight = sourceImage.size.height * scaleFactor;

        float newWidth = oldWidth * scaleFactor;

        

        UIGraphicsBeginImageContext(CGSizeMake(newWidth, newHeight));

        [sourceImage drawInRect:CGRectMake(0, 0, newWidth, newHeight)];

        UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();

        UIGraphicsEndImageContext();

        return newImage;

    }

    else//세로가 크다면

    {

        float oldWidth = sourceImage.size.height;

        float scaleFactor = size / oldWidth;

        

        float newHeight = sourceImage.size.width * scaleFactor;

        float newWidth = oldWidth * scaleFactor;

        

        UIGraphicsBeginImageContext(CGSizeMake(newWidth, newHeight));

        [sourceImage drawInRect:CGRectMake(0, 0, newWidth, newHeight)];

        UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();

        UIGraphicsEndImageContext();

        return newImage;

    }

    return sourceImage;

}