prawn:Prawn::Document#font_size
まんま
#!/usr/bin/env ruby require "prawn" Prawn::Document.generate(File.basename($0, ".rb") + ".pdf") do font_size 16 text "At size 16" font_size(10) do text "At size 10" text "At size 6", :size => 6 text "At size 10" end text "At size 16" end