class HexaPDF::Font::TrueType::Table::Head

See: developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6head.html<br><br>The ‘head’ table contains global information about the font.

def checksum_valid?

See: Table#checksum_valid?

checksum_adjustment value is not used during the calculation.
The checksum for the head table is calculated differently because the 
def checksum_valid?
  data = raw_data
  data[8, 4] = 0.chr * 4
  directory_entry.checksum == self.class.calculate_checksum(data)
end

def parse_table #:nodoc:

:nodoc: 
def parse_table #:nodoc:
  @version = read_fixed
  @font_revision = read_fixed
  data = read_formatted(46, 'N2n2q>2s>4n2s>3')
  @checksum_adjustment = data[0]
  if data[1] != 0x5F0F3CF5 # the magic number
    raise HexaPDF::Error, "Invalid magic number in 'head' table: #{data[1].to_s(16)}"
  end
  @flags, @units_per_em = data[2], data[3]
  @created, @modified = TIME_EPOCH + data[4], TIME_EPOCH + data[5]
  @bbox = data[6..9]
  @mac_style, @smallest_readable_size, @font_direction_hint, @index_to_loc_format =
    *data[10..13]
  if data[14] != 0 # glyphDataFormat
    raise HexaPDF::Error, "Invalid glyph data format value (should be 0): #{data[14]}"
  end
end