Class: TTFunk::Table::Loca

Inherits:
TTFunk::Table show all
Defined in:
lib/ttfunk/table/loca.rb

Overview

Index to Location table.

Instance Attribute Summary collapse

Attributes inherited from TTFunk::Table

#file, #length, #offset

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from TTFunk::Table

#exists?, #initialize, #raw, #tag

Constructor Details

This class inherits a constructor from TTFunk::Table

Instance Attribute Details

#offsets ⇒ Array<Integer> (readonly)

Glyph ofsets

Returns:

  • (Array<Integer>)
Source Code
lib/ttfunk/table/loca.rb, line 11
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def offsets

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  @offsets

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end

Class Method Details

.encode(offsets) ⇒ Hash

Encode table.

Parameters:

  • offsets (Array<Integer>) —

    an array of offsets, with each index corresponding to the glyph id with that index.

Returns:

  • (Hash) —

    result hash:

    • :type - the type of offset (to be encoded in the ‘head’ table):
      • 0 - short offsets
      • 1 - long offsets
    • :table - encoded bytes
Source Code
lib/ttfunk/table/loca.rb, line 22
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def self.encode(offsets)

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  long_offsets =

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    offsets.any? { |offset|

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      short_offset = offset / 2

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      short_offset * 2 != offset || short_offset > 0xffff

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    }

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  if long_offsets

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    { type: 1, table: offsets.pack('N*') }

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  else

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    { type: 0, table: offsets.map { |o| o / 2 }.pack('n*') }

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  end

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end







    
  


  

    
Instance Method Details


    
      

  

  
    #index_of(glyph_id)  ⇒ Integer 
  

  

  


  

    
Glyph offset by ID.



  





  

Parameters:


    
  
    
  • 
      
        glyph_id
      
      
        (Integer)
      
      
      
    
    • 
  




Returns:


    
  
    
  • 
      
      
        (Integer)
      
      
      
        —
        
      
  
    • offset of the glyph in the glyf table
      • 

    

    
      
    
    • 
  







  Source Code
  
lib/ttfunk/table/loca.rb, line 40

  
40
def index_of(glyph_id)

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  @offsets[glyph_id]

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end







    
      

  

  
    #size_of(glyph_id)  ⇒ Integer 
  

  

  


  

    
Size of encoded glyph.



  





  

Parameters:


    
  
    
  • 
      
        glyph_id
      
      
        (Integer)
      
      
      
    
    • 
  




Returns:


    
  
    
  • 
      
      
        (Integer)
      
      
      
    
    • 
  







  Source Code
  
lib/ttfunk/table/loca.rb, line 48

  
48
def size_of(glyph_id)

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  @offsets[glyph_id + 1] - @offsets[glyph_id]

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end