# File lib/pdf/writer.rb, line 1110
1110:   def font_descender(size = nil)
1111:     size = @font_size if size.nil? or size <= 0
1112: 
1113:     select_font("Helvetica") if @fonts.empty?
1114:     hi = @fonts[@current_font].fontbbox[1].to_f
1115:     (size * hi / 1000.0)
1116:   end