Cropped squares sometimes have either width or height that is a pixel too small

[joshbernfeld]

This problem is caused because the scale is not always a whole number in the croppedImage function.

When the rect is scaled up, non full pixels are often created. When the CGImageCreateWithImageInRect cropping function crops the image, it rounds those non full pixels up!

This can be solved by changing this

static CGRect GKScaleRect(CGRect rect, CGFloat scale)
{
    return CGRectMake(rect.origin.x * scale, rect.origin.y * scale, rect.size.width * scale, rect.size.height * scale);
}

to this

static CGRect GKScaleRect(CGRect rect, CGFloat scale)
{
    return CGRectMake(floor(rect.origin.x * scale), floor(rect.origin.y * scale), floor(rect.size.width * scale), floor(rect.size.height * scale));
}