class PDF::Reader::WidthCalculator::BuiltIn
Type1 fonts can be one of 14 “built in” standard fonts. In these cases, the reader is expected to have it’s own copy of the font metrics. see Section 9.6.2.2, PDF
32000-1:2008, pp 256
Constants
- BUILTINS
Public Class Methods
Source
# File lib/pdf/reader/width_calculator/built_in.rb, line 24 def initialize(font) @font = font @@all_metrics ||= PDF::Reader::SynchronizedCache.new basefont = extract_basefont(font.basefont) metrics_path = File.join(File.dirname(__FILE__), "..","afm","#{basefont}.afm") if File.file?(metrics_path) @metrics = @@all_metrics[metrics_path] ||= AFM::Font.new(metrics_path) else raise ArgumentError, "No built-in metrics for #{font.basefont}" end end
Public Instance Methods
Source
# File lib/pdf/reader/width_calculator/built_in.rb, line 38 def glyph_width(code_point) return 0 if code_point.nil? || code_point < 0 names = @font.encoding.int_to_name(code_point) metrics = names.map { |name| @metrics.char_metrics[name.to_s] }.compact.first if metrics metrics[:wx] else @font.widths[code_point - 1] || 0 end end
Private Instance Methods
Source
# File lib/pdf/reader/width_calculator/built_in.rb, line 55 def control_character?(code_point) match = @font.encoding.int_to_name(code_point).first.to_s[/\Acontrol..\Z/] match ? true : false end
Source
# File lib/pdf/reader/width_calculator/built_in.rb, line 60 def extract_basefont(font_name) if BUILTINS.include?(font_name) font_name.to_s else "Times-Roman" end end