prawnpdf/prawn

# frozen_string_literal: true

require 'prawn/manual_builder'

Prawn::ManualBuilder::Chapter.new do
  title 'Kerning and Character Spacing'

  text do
    prose <<~TEXT
      Kerning is the process of adjusting the spacing between characters in a
      proportional font. It is usually done with specific letter pairs. We can
      switch it on and off if it is available with the current font. Just pass
      a boolean value to the <code>:kerning</code> option of the text methods.

      Character Spacing is the space between characters. It can be increased or
      decreased and will have effect on the whole text. Just pass a number to
      the <code>:character_spacing</code> option from the text methods.
    TEXT
  end

  example new_page: true do
    font_size(30) do
      text_box 'With kerning:', kerning: true, at: [0, y - 40]
      text_box 'Without kerning:', kerning: false, at: [0, y - 80]

      text_box 'Tomato', kerning: true, at: [230, y - 40]
      text_box 'Tomato', kerning: false, at: [230, y - 80]

      text_box 'WAR', kerning: true, at: [360, y - 40]
      text_box 'WAR', kerning: false, at: [360, y - 80]

      text_box 'F.', kerning: true, at: [470, y - 40]
      text_box 'F.', kerning: false, at: [470, y - 80]
    end

    move_down 80

    string = 'What have you done to the space between the characters?'
    [-2, -1, 0, 0.5, 1, 2].each do |spacing|
      move_down 20
      text "#{string} (character_spacing: #{spacing})",
        character_spacing: spacing
    end
  end
end