# File poppler/sample/pdf2.rb, line 24
def compute_size(width, height, rotate)
  width = width.to_f
  height = height.to_f
  radius = 0
  unless rotate.zero?
    radius = rotate / 180.0 * Math::PI
    if (90 < rotate and rotate < 180) or
        (270 < rotate and rotate < 360)
      radius -= Math::PI / 2
    end
  end
  inner_angle1 = Math.atan(width / height)
  inner_angle2 = Math.atan(height / width)
  diagonal = Math.sqrt(width ** 2 + height ** 2)

  angle1 = radius + inner_angle1
  angle2 = radius + inner_angle2

  bottom1 = diagonal * Math.cos(angle1)
  length1 = (bottom1 * Math.tan(angle1)).abs.to_i
  bottom2 = diagonal * Math.cos(angle2)
  length2 = (bottom2 * Math.tan(angle2)).abs.to_i

  if (0 <= rotate and rotate <= 90) or
      (180 <= rotate and rotate <= 270)
    [length1, length2]
  else
    [length2, length1]
  end
end