libharu:HPDFPage#set_line_width
#!/usr/bin/env ruby require "hpdf" pdf = HPDFDoc.new page = pdf.add_page y = 50 [10, 20, 30].each do |w| page.set_line_width(w) page.move_to(100, y) page.line_to(200, y) page.stroke y += 50 end pdf.save_to_file(File.basename($0, ".rb") + ".pdf")