Class: Pdfrb::Font::TrueType::Glyf

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

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(data, loca = nil) ⇒ Glyf

Returns a new instance of Glyf.



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# File 'lib/pdfrb/font/true_type/glyf.rb', line 9

def initialize(data, loca = nil)
  @data = data
  @loca = loca
end

Instance Attribute Details

#data ⇒ Object (readonly)

Returns the value of attribute data.



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# File 'lib/pdfrb/font/true_type/glyf.rb', line 7

def data
  @data
end

#loca ⇒ Object (readonly)

Returns the value of attribute loca.



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# File 'lib/pdfrb/font/true_type/glyf.rb', line 7

def loca
  @loca
end

Instance Method Details

#component_glyphs(glyph_id) ⇒ Object 



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# File 'lib/pdfrb/font/true_type/glyf.rb', line 48

def component_glyphs(glyph_id)
  return [] unless composite?(glyph_id)

  g = glyph_data(glyph_id)
  return [] unless g

  components = []
  offset = 10
  loop do
    break if offset + 4 > g.bytesize

    flags = u16(g, offset)
    glyph_index = u16(g, offset + 2)
    components << glyph_index
    offset += 4

    offset += 4 if flags & 0x0001 != 0
    offset += 2 if flags & 0x0002 != 0
    break if flags.nobits?(0x0020)
  end
  components
end

#composite?(glyph_id) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/pdfrb/font/true_type/glyf.rb', line 38

def composite?(glyph_id)
  h = glyph_header(glyph_id)
  h && h[:number_of_contours].negative?
end

#empty?(glyph_id) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/pdfrb/font/true_type/glyf.rb', line 43

def empty?(glyph_id)
  length = @loca&.glyph_length(glyph_id) || 0
  length.zero?
end

#glyph_data(glyph_id) ⇒ Object 



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# File 'lib/pdfrb/font/true_type/glyf.rb', line 14

def glyph_data(glyph_id)
  return nil unless @data && @loca
  return nil if glyph_id >= @loca.offsets.length - 1

  offset = @loca.glyph_offset(glyph_id)
  length = @loca.glyph_length(glyph_id)
  return nil if offset.nil? || length.zero?

  @data.byteslice(offset, length)
end

#glyph_header(glyph_id) ⇒ Object 



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# File 'lib/pdfrb/font/true_type/glyf.rb', line 25

def glyph_header(glyph_id)
  g = glyph_data(glyph_id)
  return nil unless g && g.bytesize >= 10

  {
    number_of_contours: s16(g, 0),
    x_min: s16(g, 2),
    y_min: s16(g, 4),
    x_max: s16(g, 6),
    y_max: s16(g, 8),
  }
end