code: def getRotatedSize(corners, angle):
      
      if angle:
          _rotm = fileutil.buildRotMatrix(angle)
          # Rotate about the center
          _corners = np.dot(corners, _rotm)
      else:
          # If there is no rotation, simply return original values
          _corners = corners
  
      return computeRange(_corners)
docs: Determine the size of a rotated (meta)image.