Class: Pdfrb::Font::TrueType::Hmtx

Inherits:
Object
  • Object
show all
Defined in:
lib/pdfrb/font/true_type/hmtx.rb

Overview

hmtx (Horizontal Metrics) table parser. Provides per-glyph advance widths and left-side bearings.

Layout: numberOfHMetrics records of (u16 advance, u16 lsb), followed by (numGlyphs - numberOfHMetrics) u16 lsbs (those glyphs share the last advance width).

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(data, number_of_hmetrics:) ⇒ Hmtx

Returns a new instance of Hmtx.



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# File 'lib/pdfrb/font/true_type/hmtx.rb', line 15

def initialize(data, number_of_hmetrics:)
  @data = data || "".b
  @number_of_hmetrics = number_of_hmetrics
  parse
end

Instance Attribute Details

#advances ⇒ Object (readonly)

Returns the value of attribute advances.



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# File 'lib/pdfrb/font/true_type/hmtx.rb', line 13

def advances
  @advances
end

#lsbs ⇒ Object (readonly)

Returns the value of attribute lsbs.



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# File 'lib/pdfrb/font/true_type/hmtx.rb', line 13

def lsbs
  @lsbs
end

#number_of_hmetrics ⇒ Object (readonly)

Returns the value of attribute number_of_hmetrics.



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# File 'lib/pdfrb/font/true_type/hmtx.rb', line 13

def number_of_hmetrics
  @number_of_hmetrics
end

Instance Method Details

#advance_width(glyph_id) ⇒ Object 



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# File 'lib/pdfrb/font/true_type/hmtx.rb', line 21

def advance_width(glyph_id)
  return 0 if @advances.empty?

  if glyph_id < @number_of_hmetrics
    @advances[glyph_id]
  else
    @advances.last
  end
end

#lsb(glyph_id) ⇒ Object 



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# File 'lib/pdfrb/font/true_type/hmtx.rb', line 31

def lsb(glyph_id)
  @lsbs[glyph_id] || @lsbs.last || 0
end