Class: TTFunk::Table::Glyf::Compound

Inherits:
Object
  • Object
show all
Includes:
Reader
Defined in:
lib/ttfunk/table/glyf/compound.rb

Defined Under Namespace

Classes: Component

Constant Summary collapse

ARG_1_AND_2_ARE_WORDS = 
0x0001
WE_HAVE_A_SCALE = 
0x0008
MORE_COMPONENTS = 
0x0020
WE_HAVE_AN_X_AND_Y_SCALE = 
0x0040
WE_HAVE_A_TWO_BY_TWO = 
0x0080
WE_HAVE_INSTRUCTIONS = 
0x0100

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(raw, x_min, y_min, x_max, y_max) ⇒ Compound

Returns a new instance of Compound.



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# File 'lib/ttfunk/table/glyf/compound.rb', line 22

def initialize(raw, x_min, y_min, x_max, y_max)
  @raw = raw
  @x_min, @y_min, @x_max, @y_max = x_min, y_min, x_max, y_max

  # Because TTFunk only cares about glyphs insofar as they (1) provide
  # a bounding box for each glyph, and (2) can be rewritten into a
  # font subset, we don't really care about the rest of the glyph data
  # except as a whole. Thus, we don't actually decompose the glyph
  # into it's parts--all we really care about are the locations within
  # the raw string where the component glyph ids are stored, so that
  # when we rewrite this glyph into a subset we can rewrite the
  # component glyph-ids so they are correct for the subset.

  @glyph_ids = []
  @glyph_id_offsets = []
  offset = 10 # 2 bytes for each of num-contours, min x/y, max x/y

  loop do
    flags, glyph_id = @raw[offset, 4].unpack("n*")
    @glyph_ids << glyph_id
    @glyph_id_offsets << offset + 2

    break unless flags & MORE_COMPONENTS != 0
    offset += 4

    if flags & ARG_1_AND_2_ARE_WORDS != 0
      offset += 4
    else
      offset += 2
    end

    if flags & WE_HAVE_A_TWO_BY_TWO != 0
      offset += 8
    elsif flags & WE_HAVE_AN_X_AND_Y_SCALE != 0
      offset += 4
    elsif flags & WE_HAVE_A_SCALE != 0
      offset += 2
    end
  end
end

Instance Attribute Details

#glyph_ids ⇒ Object (readonly)

Returns the value of attribute glyph_ids.



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# File 'lib/ttfunk/table/glyf/compound.rb', line 18

def glyph_ids
  @glyph_ids
end

#raw ⇒ Object (readonly)

Returns the value of attribute raw.



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# File 'lib/ttfunk/table/glyf/compound.rb', line 16

def raw
  @raw
end

#x_max ⇒ Object (readonly)

Returns the value of attribute x_max.



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# File 'lib/ttfunk/table/glyf/compound.rb', line 17

def x_max
  @x_max
end

#x_min ⇒ Object (readonly)

Returns the value of attribute x_min.



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# File 'lib/ttfunk/table/glyf/compound.rb', line 17

def x_min
  @x_min
end

#y_max ⇒ Object (readonly)

Returns the value of attribute y_max.



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# File 'lib/ttfunk/table/glyf/compound.rb', line 17

def y_max
  @y_max
end

#y_min ⇒ Object (readonly)

Returns the value of attribute y_min.



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# File 'lib/ttfunk/table/glyf/compound.rb', line 17

def y_min
  @y_min
end

Instance Method Details

#compound? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ttfunk/table/glyf/compound.rb', line 63

def compound?
  true
end

#recode(mapping) ⇒ Object 



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# File 'lib/ttfunk/table/glyf/compound.rb', line 67

def recode(mapping)
  result = @raw.dup
  new_ids = glyph_ids.map { |id| mapping[id] }

  new_ids.zip(@glyph_id_offsets).each do |new_id, offset|
    result[offset, 2] = [new_id].pack("n")
  end

  return result
end