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.

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

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

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:

Source Code
lib/ttfunk/subset/base.rb, line 33
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def initialize(original)

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  @original = original

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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:

Source Code
lib/ttfunk/subset/base.rb, line 30
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def original

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  @original

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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:

  • glyph_ids (Array<Integer>)

Returns:

Source Code
lib/ttfunk/subset/base.rb, line 98
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def collect_glyphs(glyph_ids)

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  collected =

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    glyph_ids.each_with_object({}) do |id, h|

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      h[id] = glyph_for(id)

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    end

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  additional_ids = collected.values

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    .select { |g| g && g.compound? }

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    .map(&:glyph_ids)

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    .flatten

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

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  collected

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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:


    
  
    
  • 
      
        options
      
      
        (Hash)
      
      
        (defaults to: {})
      
      
    
    • 
  




Returns:


    
  
    
  • 
      
      
        (String)
      
      
      
    
    • 
  







  Source Code
  
lib/ttfunk/subset/base.rb, line 63

  
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def encode(options = {})

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  encoder_klass.new(original, self, options).encode

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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:







  Source Code
  
lib/ttfunk/subset/base.rb, line 70

  
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def encoder_klass

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  original.cff.exists? ? OTFEncoder : TTFEncoder

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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:







  Source Code
  
lib/ttfunk/subset/base.rb, line 87

  
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def glyphs

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  @glyphs ||= collect_glyphs(original_glyph_ids)

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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:


    
  
    
  • 
      
      
        (Boolean)
      
      
      
    
    • 
  







  Source Code
  
lib/ttfunk/subset/base.rb, line 47

  
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def microsoft_symbol?

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  new_cmap_table[:platform_id] == MICROSOFT_PLATFORM_ID &&

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    new_cmap_table[:encoding_id] == MS_SYMBOL_ENCODING_ID

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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:


    
  
    
  • 
      
      
        (Hash{Integer => Integer})
      
      
      
    
    • 
  







  Source Code
  
lib/ttfunk/subset/base.rb, line 142

  
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def new_to_old_glyph

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  @new_to_old_glyph ||= old_to_new_glyph.invert

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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:


    
  
    
  • 
      
      
        (Hash{Integer => Integer})
      
      
      
    
    • 
  







  Source Code
  
lib/ttfunk/subset/base.rb, line 117

  
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def old_to_new_glyph

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  @old_to_new_glyph ||=

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    begin

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      charmap = new_cmap_table[:charmap]

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      old_to_new =

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        charmap.each_with_object(0 => 0) do |(_, ids), map|

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          map[ids[:old]] = ids[:new]

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        end

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      next_glyph_id = new_cmap_table[:max_glyph_id]

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      glyphs.each_key do |old_id|

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        unless old_to_new.key?(old_id)

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          old_to_new[old_id] = next_glyph_id

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          next_glyph_id += 1

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        end

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      end

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      old_to_new

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    end

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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:


    
  
    
  • 
      
      
        (Hash{Integer => Integer})
      
      
      
    
    • 
  







  Source Code
  
lib/ttfunk/subset/base.rb, line 55

  
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def to_unicode_map

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  {}

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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:


    
  
    
  • 
      
      
        (Boolean)
      
      
      
    
    • 
  







  Source Code
  
lib/ttfunk/subset/base.rb, line 40

  
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def unicode?

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  false

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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:







  Source Code
  
lib/ttfunk/subset/base.rb, line 77

  
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def unicode_cmap

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

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end