Class: Idml::TextEngine::Justifier

Inherits:
Object
  • Object
show all
Defined in:
lib/idml/text_engine/justifier.rb

Overview

Distributes slack space within a line per the paragraph's alignment. Adjusts x_offset and optionally scales inter-word spaces for justified text. last_line: (the paragraph's final line) keeps ragged right under :justified, as InDesign does.

Defined Under Namespace

Classes: SpacingLimits

Constant Summary collapse

DEFAULT_MAX_WORD_SPACING = 
133.0
DEFAULT_MAX_LETTER_SPACING = 
0.0

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(frame_width, alignment, last_line, limits) ⇒ Justifier

Returns a new instance of Justifier.



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# File 'lib/idml/text_engine/justifier.rb', line 24

def initialize(frame_width, alignment, last_line, limits)
  @frame_width = frame_width
  @alignment = alignment
  @last_line = last_line
  @limits = limits
end

Class Method Details

.justify(line:, frame_width:, alignment: :left, last_line: false, limits: nil) ⇒ Object 



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# File 'lib/idml/text_engine/justifier.rb', line 19

def self.justify(line:, frame_width:, alignment: :left,
                 last_line: false, limits: nil)
  new(frame_width, alignment, last_line, limits).justify(line)
end

Instance Method Details

#justify(line) ⇒ Object 



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# File 'lib/idml/text_engine/justifier.rb', line 31

def justify(line)
  case effective_alignment
  when :left, :start then line.x_offset = 0
  when :center, :middle
    line.x_offset = (@frame_width - line.width) / 2
  when :right, :end
    line.x_offset = @frame_width - line.width
  when :justified then justify_line(line)
  end
  line
end