class TTFunk::Table::Glyf

Glyph Data (‘glyf`) table.

Public Class Methods

encode(glyphs, new_to_old, old_to_new) click to toggle source

Encode table.

@param glyphs [Hash] a hash mapping (old) glyph-ids to glyph objects @param new_to_old [Hash{Integer => Integer}] a hash mapping new glyph

IDs to glyph IDs in the original font.

@param old_to_new [Hash{Integer => Integer}] a hash mapping old glyph

IDs to new glyph IDs.

@return [Hash]

* `:table` (<tt>String</tt>) - encoded table.
* `:offsets` (<tt>Array\<Integer></tt>) - glyph offsets in the table.
# File lib/ttfunk/table/glyf.rb, line 19
def self.encode(glyphs, new_to_old, old_to_new)
  result = { table: +'', offsets: [] }

  new_to_old.keys.sort.each do |new_id|
    glyph = glyphs[new_to_old[new_id]]
    result[:offsets] << result[:table].length
    result[:table] << glyph.recode(old_to_new) if glyph
  end

  # include an offset at the end of the table, for use in computing the
  # size of the last glyph
  result[:offsets] << result[:table].length
  result
end

Public Instance Methods

for(glyph_id) click to toggle source

Get glyph by ID.

@param glyph_id [Integer] @return [TTFunk::Table::Glyf::Simple, TTFunk::Table::Glyf::Compound,

nil]
# File lib/ttfunk/table/glyf.rb, line 39
def for(glyph_id)
  return @cache[glyph_id] if @cache.key?(glyph_id)

  index = file.glyph_locations.index_of(glyph_id)
  size = file.glyph_locations.size_of(glyph_id)

  if size.zero? # blank glyph, e.g. space character
    @cache[glyph_id] = nil
    return
  end

  parse_from(offset + index) do
    raw = io.read(size)
    number_of_contours = to_signed(raw.unpack1('n'))

    @cache[glyph_id] =
      if number_of_contours == -1
        Compound.new(glyph_id, raw)
      else
        Simple.new(glyph_id, raw)
      end
  end
end

Private Instance Methods

parse!() click to toggle source
# File lib/ttfunk/table/glyf.rb, line 65
def parse!
  # because the glyf table is rather complex to parse, we defer
  # the parse until we need a specific glyf, and then cache it.
  @cache = {}
end