module TTFunk::Table::Cmap::Format12
Format 12: Segmented coverage.
This module conditionally extends {TTFunk::Table::Cmap::Subtable}.
Attributes
Code map. @return [Hash{Integer => Integer}]
Language. @return [Integer]
Public Class Methods
Source
# File lib/ttfunk/table/cmap/format12.rb, line 30 def self.encode(charmap) next_id = 0 glyph_map = { 0 => 0 } range_firstglyphs = [] range_firstcodes = [] range_lengths = [] last_glyph = last_code = -999 new_map = charmap.keys.sort.each_with_object({}) do |code, map| glyph_map[charmap[code]] ||= next_id += 1 map[code] = { old: charmap[code], new: glyph_map[charmap[code]] } if code > last_code + 1 || glyph_map[charmap[code]] > last_glyph + 1 range_firstcodes << code range_firstglyphs << glyph_map[charmap[code]] range_lengths << 1 else range_lengths.push(range_lengths.pop) + 1 end last_code = code last_glyph = glyph_map[charmap[code]] end subtable = [ 12, 0, 16 + (12 * range_lengths.size), 0, range_lengths.size, ].pack('nnNNN') range_lengths.each_with_index do |length, i| firstglyph = range_firstglyphs[i] firstcode = range_firstcodes[i] subtable << [ firstcode, firstcode + length - 1, firstglyph, ].pack('NNN') end { charmap: new_map, subtable: subtable, max_glyph_id: next_id + 1 } end
Encode the encoding record to format 12.
@param charmap [Hash{Integer => Integer}] a hash mapping character
codes to glyph IDs from the original font.
@return [Hash]
* `:charmap` (<tt>Hash{Integer => Hash}</tt>) keys are the characrers in `charset`, values are hashes: * `:old` (<tt>Integer</tt>) - glyph ID in the original font. * `:new` (<tt>Integer</tt>) - glyph ID in the subset font. that maps the characters in charmap to a * `:subtable` (<tt>String</tt>) - serialized encoding record. * `:max_glyph_id` (<tt>Integer</tt>) - maximum glyph ID in the new font.
Public Instance Methods
Source
# File lib/ttfunk/table/cmap/format12.rb, line 72 def [](code) @code_map[code] || 0 end
Get glyph ID for character code.
@param code [Integer] character code. @return [Integer] glyph ID.
Source
# File lib/ttfunk/table/cmap/format12.rb, line 79 def supported? true end
Is this encoding record format supported?
@return [true]
Private Instance Methods
Source
# File lib/ttfunk/table/cmap/format12.rb, line 85 def parse_cmap! fractional_version, @language, groupcount = read(14, 'nx4NN') if fractional_version != 0 raise NotImplementedError, "cmap version 12.#{fractional_version} is not supported" end @code_map = {} (1..groupcount).each do startchar, endchar, startglyph = read(12, 'NNN') (0..(endchar - startchar)).each do |offset| @code_map[startchar + offset] = startglyph + offset end end end