class Paperclip::Geometry

def cropping dst, ratio, scale
  if ratio.horizontal? || ratio.square?
    "%dx%d+%d+%d" % [ dst.width, dst.height, 0, (self.height * scale - dst.height) / 2 ]
  else
    "%dx%d+%d+%d" % [ dst.width, dst.height, (self.width * scale - dst.width) / 2, 0 ]
  end
end