Class: HexaPDF::Font::TrueType::Table::Glyf

Inherits:
HexaPDF::Font::TrueType::Table show all
Defined in:
lib/hexapdf/font/true_type/table/glyf.rb

Overview

The ‘glyf’ table contains the instructions for rendering glyphs and some additional glyph information.

This is probably always the largest table in a TrueType font, so care is taken to perform operations lazily.

See: developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6glyf.html

Defined Under Namespace

Classes: Glyph

Constant Summary

Constants inherited from HexaPDF::Font::TrueType::Table

TIME_EPOCH

Instance Attribute Summary collapse

Attributes inherited from HexaPDF::Font::TrueType::Table

#font

Instance Method Summary collapse

Methods inherited from HexaPDF::Font::TrueType::Table

calculate_checksum, #checksum_valid?, #directory_entry, #initialize, #raw_data

Constructor Details

This class inherits a constructor from HexaPDF::Font::TrueType::Table

Instance Attribute Details

#glyphs ⇒ Object

The mapping from glyph ID to Glyph object or nil (if the glyph has no outline).



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# File 'lib/hexapdf/font/true_type/table/glyf.rb', line 139

def glyphs
  @glyphs
end

Instance Method Details

#[](glyph_id) ⇒ Object

Returns the Glyph object for the given glyph ID. If the glyph has no outline (e.g. the space character), an empty Glyph object is returned.



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# File 'lib/hexapdf/font/true_type/table/glyf.rb', line 143

def [](glyph_id)
  return @glyphs[glyph_id] if @glyphs.key?(glyph_id)

  offset = font[:loca].offset(glyph_id)
  length = font[:loca].length(glyph_id)

  if length == 0
    @glyphs[glyph_id] = Glyph.new('')
  else
    raw_data = with_io_pos(directory_entry.offset + offset) { io.read(length) }
    @glyphs[glyph_id] = Glyph.new(raw_data)
  end
end