Class: FontProcessor::FontFile

Inherits:
Object
  • Object
show all
Defined in:
lib/fontprocessor/font_file.rb

Overview

Inspects an OpenType font file for various tidbits of information.

Instance Method Summary collapse

Constructor Details

#initialize(filename) ⇒ FontFile

Returns a new instance of FontFile.



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# File 'lib/fontprocessor/font_file.rb', line 4

def initialize(filename)
  @filename = filename
  raise "Font file not found: #{@filename}" unless File.exists? @filename
  @font_manipulator = Skytype::FontManipulator.new(File.binread(@filename))
  raise "Failed to create Skytype::FontManipulator" if @font_manipulator.nil?
  @unicode = nil
end

Instance Method Details

#features ⇒ Object

Public: Gets a list of GSUB and GPOS features, in a simpler version than that returned by skytype.

Returns a JSON formatted string of GSUB and GPOS features



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# File 'lib/fontprocessor/font_file.rb', line 67

def features
  feature_hash = {}
  features = JSON.parse @font_manipulator.extract_features
  features['tables'].each do |table|
    feature_hash["#{table['tag']}"] = []
    table['features'].each do |feature|
      feature_hash["#{table['tag']}"].push feature['tag']
    end
  end
  JSON.generate feature_hash
end

#glyph_count ⇒ Object

Public: Gets the total number of glyphs in the font.

Returns an unsigned 16-bit integer



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# File 'lib/fontprocessor/font_file.rb', line 52

def glyph_count
  @font_manipulator.get_num_glyphs
end

#has_postscript_outlines? ⇒ Boolean

Returns true when the font contains PostScript (sometimes referred to as CFF) outlines

Returns:

  • (Boolean) 


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# File 'lib/fontprocessor/font_file.rb', line 100

def has_postscript_outlines?
  @font_manipulator.is_post_script_font?
end

#has_truetype_outlines? ⇒ Boolean

Returns true when the font contains TrueType (sometimes referred to as TT) outlines

Returns:

  • (Boolean) 


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# File 'lib/fontprocessor/font_file.rb', line 106

def has_truetype_outlines?
  @font_manipulator.has_table("glyf")
end

#metrics ⇒ Object

Public: Inspects the font for various pieces of metadata (mostly metrics) about the font.

Returns Hash including the following keys:

em, max_ascent, max_descent, os2_panose, upos,
optical_size, os2_winascent, os2_windescent,
os2_typoascent, os2_typodescent, os2_typolinegap,
hhea_ascent, hhea_descent, hhea_linegap
os2_weight, os2_width



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# File 'lib/fontprocessor/font_file.rb', line 43

def metrics
  metrics ||= Skytype::FontUtils.get_metrics_as_hash(@font_manipulator)
  metrics.merge!({ "optical_size" => optical_size }) unless metrics.has_key?("optical_size")
  metrics
end

#names ⇒ Object

Public: Inspects the name table of the font, which contains various metadata from the foundry/designer.

In reality these table contains localized versions of these strings for multiple operating systems. To simplify things, we have chosen to use only use the English versions of these names for the Windows Platform.

Most of the time this isn’t an issue however occasionally foundries/designers place different values in different platforms/languages.

Returns a Hash of name record labels and their values. Possible keys include:

'Copyright', 'Family', 'Subfamily', 'Unique ID', 'Full name',
'Version', 'PostScript name', 'Trademark', 'Manufacturer', 'Designer',
'Description', 'Vendor URL', 'Designer URL', 'License Description',
'License URL', 'Reserved', 'Preferred Family', 'Preferred Subfamily',
'Compatible Full', 'Sample text', 'PostScript CID', 'WWS Family Name',
'WWS Subfamily Name'



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# File 'lib/fontprocessor/font_file.rb', line 30

def names
  Skytype::FontUtils.get_names_as_hash(@font_manipulator)
end

#optical_size ⇒ Object

Public: Gets any Optical Size feature from the font.

Returns an unsigned 32-bit integer or nil if no Optical Size feature exists



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# File 'lib/fontprocessor/font_file.rb', line 59

def optical_size
  @font_manipulator.get_optical_size
end

#unicode ⇒ Object

Public: Inspects which Unicode values are contained within the font.

Returns an Array of Unicode ids represented as Fixnums contained within the font.



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# File 'lib/fontprocessor/font_file.rb', line 83

def unicode
  @unicode ||= @font_manipulator.unicode_as_binary_entries
  @unicode
end

#unicode_ranges ⇒ Object

Public: similar to .unicode, it returns the same data but in a compact form where contigious integers are represented as a Range.

Returns an Array of Unicode ids represented as Fixnums (or Ranges if contigious) contained within the font. Characters which in the cmap table are not returned.



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# File 'lib/fontprocessor/font_file.rb', line 94

def unicode_ranges
  compact_ranges(unicode)
end