Class: HexaPDF::Type::FontSimple

Inherits:
Font show all
Defined in:
lib/hexapdf/type/font_simple.rb

Overview

Represents a simple PDF font.

A simple font has only single-byte character codes and only supports horizontal metrics.

See: PDF1.7 s9.6

Direct Known Subclasses

FontTrueType, FontType1, FontType3

Constant Summary

Constants included from DictionaryFields

DictionaryFields::Boolean, DictionaryFields::PDFByteString, DictionaryFields::PDFDate

Instance Attribute Summary

Attributes inherited from Object

#data, #document, #must_be_indirect

Instance Method Summary collapse

Methods inherited from Font

#bounding_box, #embedded?, #font_file, #font_wrapper, #font_wrapper=, #must_be_indirect?

Methods inherited from Dictionary

#[], #[]=, define_field, define_type, #delete, #each, each_field, #empty?, field, #key?, #to_h, type, #type

Methods inherited from Object

#<=>, #==, #cache, #cached?, #clear_cache, deep_copy, #deep_copy, #document?, #eql?, #gen, #gen=, #hash, #indirect?, #initialize, #inspect, #must_be_indirect?, #null?, #oid, #oid=, #type, #validate, #value, #value=

Constructor Details

This class inherits a constructor from HexaPDF::Object

Instance Method Details

#decode(string) ⇒ Object

Decodes the given string into an array of character codes.



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# File 'lib/hexapdf/type/font_simple.rb', line 84

def decode(string)
  string.bytes
end

#encoding ⇒ Object

Returns the encoding object used for this font.

Note that the encoding is cached internally when accessed the first time.



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# File 'lib/hexapdf/type/font_simple.rb', line 59

def encoding
  cache(:encoding) do
    case (val = self[:Encoding])
    when Symbol
      encoding = HexaPDF::Font::Encoding.for_name(val)
      encoding = encoding_from_font if encoding.nil?
      encoding
    when HexaPDF::Dictionary
      encoding = val[:BaseEncoding] && HexaPDF::Font::Encoding.for_name(val[:BaseEncoding])
      encoding ||= if embedded? || symbolic?
                     encoding_from_font
                   else
                     HexaPDF::Font::Encoding.for_name(:StandardEncoding)
                   end
      encoding = difference_encoding(encoding, val[:Differences]) if val.key?(:Differences)
      encoding
    when nil
      encoding_from_font
    else
      raise HexaPDF::Error, "Unknown value for font's encoding: #{self[:Encoding]}"
    end
  end
end

#symbolic? ⇒ Boolean

Returns true if the font is a symbolic font, false if it is not, and nil if it is not known.



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# File 'lib/hexapdf/type/font_simple.rb', line 117

def symbolic?
  self[:FontDescriptor]&.flagged?(:symbolic)
end

#to_utf8(code) ⇒ Object

Returns the UTF-8 string for the given character code, or calls the configuration option ‘font.on_missing_unicode_mapping’ if no mapping was found.



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# File 'lib/hexapdf/type/font_simple.rb', line 90

def to_utf8(code)
  to_unicode_cmap&.to_unicode(code) || encoding.unicode(code) || missing_unicode_mapping(code)
end

#width(code) ⇒ Object

Returns the unscaled width of the given code point in glyph units, or 0 if the width for the code point is missing.



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# File 'lib/hexapdf/type/font_simple.rb', line 96

def width(code)
  widths = self[:Widths]
  first_char = self[:FirstChar]
  last_char = self[:LastChar]

  if widths && code >= first_char && code <= last_char
    widths[code - first_char]
  elsif widths && key?(:FontDescriptor)
    self[:FontDescriptor][:MissingWidth]
  else
    0
  end
end

#word_spacing_applicable? ⇒ Boolean

Returns whether word spacing is applicable when using this font.

Always returns true for simple fonts.

See: PDF1.7 s9.3.3



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# File 'lib/hexapdf/type/font_simple.rb', line 126

def word_spacing_applicable?
  true
end

#writing_mode ⇒ Object

Returns the writing mode which is always :horizontal for simple fonts like Type1.



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# File 'lib/hexapdf/type/font_simple.rb', line 111

def writing_mode
  :horizontal
end