Ruby - 如何在 Prawn 中使用不同的字体？

Prawn::Document.generate("output.pdf") do
  font_families.update("Arial" => {
    :normal => "/assets/fonts/Arial.ttf",
    :italic => "/assets/fonts/Arial Italic.ttf",
  })
  font "Arial"
end

## bundle exec rails runner ContactEnsureAttachment.prawn_test -e production
  def self.prawn_test
    template_filename = "#{Rails.root}/public/ensure_file.pdf"
    prawn_filename = "#{Rails.root}/public/temp.pdf"
    output_filename = "#{Rails.root}/public/output.pdf"

    Prawn::Document.generate(prawn_filename) do
      start_new_page  ##　增加新一页
      fill_color 'ff0000'
      stroke_color 'ff0000'
      # fill_polygon [50, 150], [150, 200], [250, 150], [250, 50], [150, 0], [50, 50]
      # # Stroke with Purple using CMYK
      # stroke_color 50, 100, 0, 0
      # stroke_rectangle [300, 300], 200, 100
      # # Both together
      stroke_circle [738, 340], 25
      stroke_circle [738, 165], 25

      # bounding_box([100, 300], width: 300, height: 200) do
      #   stroke_bounds
      #   stroke_circle [0, 0], 10
      # end

      # font_families.update(
      #   "STFANGSO" => {
      #     :normal => "app/assets/fonts/STFANGSO.TTF"
      #   }
      # )
      # font "STFANGSO"
      font Rails.root.join("app/assets/fonts/simhei.ttf")
      
      # 鈴木
      ensure_debit_person = "鈴木鈴鈴木"
      ensure_credit_person = "木"

      ensure_debit_person_all = "鈴木 鈴"
      ensure_credit_person_all = "鈴 木木"

      pp ensure_debit_person_all.length
      pp "ddddd"

      text_debit_preson_opts = ContactEnsureAttachment.get_sign_opts(ensure_debit_person.length, "debit")
      text_credit_preson_opts = ContactEnsureAttachment.get_sign_opts(ensure_credit_person.length, "credit")

      # draw_text "藤 一", :at => [734,360], kerning: true, rotate: 270#, align: :center
      # 358
      text_box "#{ensure_debit_person}", text_debit_preson_opts#at: [719, 349], width: 18, size: 18#, overflow: :shrink_to_fit, min_font_size: 10#, align: :center, valign: :center#, style: [:bold, :italic]
      # draw_text "kai", :at => [734,185], kerning: true, rotate: 270#, align: :center
      # 174
      text_box "#{ensure_credit_person}", text_credit_preson_opts#at: [719, 174], width: 18, size: 18#, align: :center, valign: :center#, style: [:bold, :italic]
      
      fill_color '000000'
      text_box "#{ensure_debit_person_all}", at: [450, 349], size: 14, width:14*ensure_debit_person_all.length
      text_box "#{ensure_credit_person_all}", at: [450, 167], size: 14, width: 14*ensure_credit_person_all.length
      text_box "#{ensure_debit_person_all}", at: [450, 390], size: 12, width: 12*ensure_debit_person_all.length
    end

    company_logo = CombinePDF.load("#{Rails.root}/public/temp.pdf").pages[1]
    pdf = CombinePDF.load "#{Rails.root}/public/aaaa.pdf"
    # pdf.pages.each { |page| page << company_logo } 
    pdf.pages[0] << company_logo
    pdf.save "#{Rails.root}/public/aaaa.pdf"
  end