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
new(font)
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# File lib/pdf/reader/width_calculator/built_in.rb, line 23 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
glyph_width(code_point)
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# File lib/pdf/reader/width_calculator/built_in.rb, line 37 def glyph_width(code_point) return 0 if code_point.nil? || code_point < 0 m = @metrics.char_metrics_by_code[code_point] if m.nil? names = @font.encoding.int_to_name(code_point) m = names.map { |name| @metrics.char_metrics[name.to_s] }.compact.first end if m m[:wx] elsif @font.widths[code_point - 1] @font.widths[code_point - 1] elsif control_character?(code_point) 0 else 0 end end
Private Instance Methods
control_character?(code_point)
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# File lib/pdf/reader/width_calculator/built_in.rb, line 62 def control_character?(code_point) @font.encoding.int_to_name(code_point).first.to_s[/\Acontrol..\Z/] end
extract_basefont(font_name)
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# File lib/pdf/reader/width_calculator/built_in.rb, line 66 def extract_basefont(font_name) if BUILTINS.include?(font_name) font_name else "Times-Roman" end end