Class: TTFunk::Subset::Base Private

Inherits:
Object
  • Object
show all
Defined in:
lib/ttfunk/subset/base.rb

Overview

This class is part of a private API. You should avoid using this class if possible, as it may be removed or be changed in the future.

Base subset.

API:

  • private

Direct Known Subclasses

CodePage, Unicode, Unicode8Bit

Constant Summary collapse

MICROSOFT_PLATFORM_ID =

This constant is part of a private API. You should avoid using this constant if possible, as it may be removed or be changed in the future.

Microsoft Platform ID

API:

  • private

3
MS_SYMBOL_ENCODING_ID =

This constant is part of a private API. You should avoid using this constant if possible, as it may be removed or be changed in the future.

Symbol Encoding ID for Microsoft Platform

API:

  • private

0

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(original) ⇒ Base

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a new instance of Base.

Parameters:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 33

def initialize(original)
  @original = original
end

Instance Attribute Details

#original ⇒ TTFunk::File (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Original font

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 30

def original
  @original
end

Instance Method Details

#collect_glyphs(glyph_ids) ⇒ Hash{Integer => TTFunk::Table::Glyf::Simple, TTFunk::Table::Glyf::Compound>, Hash{Integer => TTFunk::Table::Cff::Charstring}

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Get glyphs by their IDs in the original font.

Parameters:

Returns:

  • if original is a TrueType font

  • if original is a CFF-based OpenType font

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 98

def collect_glyphs(glyph_ids)
  collected =
    glyph_ids.each_with_object({}) do |id, h|
      h[id] = glyph_for(id)
    end

  additional_ids = collected.values
    .select { |g| g && g.compound? }
    .map(&:glyph_ids)
    .flatten

  collected.update(collect_glyphs(additional_ids)) if additional_ids.any?

  collected
end

#encode(options = {}) ⇒ String

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Encode this subset into a binary font representation.

Parameters:

  • (defaults to: {})

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 63

def encode(options = {})
  encoder_klass.new(original, self, options).encode
end

#encoder_klass ⇒ TTFunk::TTFEncoder, TTFunk::OTFEncoder

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Encoder class for this subset.

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 70

def encoder_klass
  original.cff.exists? ? OTFEncoder : TTFEncoder
end

#glyphs ⇒ Hash{Integer => TTFunk::Table::Glyf::Simple, TTFunk::Table::Glyf::Compound}, Hash{Integer => TTFunk::Table::Cff::Charstring] if original is a CFF-based OpenType font

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Get glyphs in this subset.

Returns:

  • if original is a TrueType font

  • Hash{Integer => TTFunk::Table::Cff::Charstring] if original is a CFF-based OpenType font

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 87

def glyphs
  @glyphs ||= collect_glyphs(original_glyph_ids)
end

#microsoft_symbol? ⇒ Boolean

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Does this subset use Microsoft Symbolic encoding?

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 47

def microsoft_symbol?
  new_cmap_table[:platform_id] == MICROSOFT_PLATFORM_ID &&
    new_cmap_table[:encoding_id] == MS_SYMBOL_ENCODING_ID
end

#new_to_old_glyph ⇒ Hash{Integer => Integer}

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Glyph ID mapping from this subset to the original font.

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 142

def new_to_old_glyph
  @new_to_old_glyph ||= old_to_new_glyph.invert
end

#old_to_new_glyph ⇒ Hash{Integer => Integer}

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Glyph ID mapping from the original font to this subset.

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 117

def old_to_new_glyph
  @old_to_new_glyph ||=
    begin
      charmap = new_cmap_table[:charmap]
      old_to_new =
        charmap.each_with_object(0 => 0) do |(_, ids), map|
          map[ids[:old]] = ids[:new]
        end

      next_glyph_id = new_cmap_table[:max_glyph_id]

      glyphs.each_key do |old_id|
        unless old_to_new.key?(old_id)
          old_to_new[old_id] = next_glyph_id
          next_glyph_id += 1
        end
      end

      old_to_new
    end
end

#to_unicode_map ⇒ Hash{Integer => Integer}

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Get a mapping from this subset to Unicode.

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 55

def to_unicode_map
  {}
end

#unicode? ⇒ Boolean

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Is this Unicode-based subset?

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 40

def unicode?
  false
end

#unicode_cmap ⇒ TTFunk::Table::Cmap::Subtable

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Get the first Unicode cmap from the original font.

Returns:

API:

  • private



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# File 'lib/ttfunk/subset/base.rb', line 77

def unicode_cmap
  @unicode_cmap ||= @original.cmap.unicode.first
end