def _draw_rectangle(context, width, height):
        """Draw a rectangle

        Assertion: The current point is the center point of the rectangle

        :param context: Cairo context
        :param width: Width of the rectangle
        :param height: Height of the rectangle
        """
        c = context
        # First move to upper left corner
        c.rel_move_to(-width / 2., -height / 2.)
        # Draw closed rectangle
        c.rel_line_to(width, 0)
        c.rel_line_to(0, height)
        c.rel_line_to(-width, 0)
        c.close_path()