Class: AFM::Font

Inherits:
Object
  • Object
show all
Defined in:
lib/pdf/reader/width_calculator/built_in.rb

Overview

monkey patch the afm gem to give us access to the metrics by glyph code. I’ve got a pull request to upstream so hopefully this can be removed soon. See github.com/halfbyte/afm/pull/3

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(filename) ⇒ Font

Loading a Font Metrics file by absolute path (no automatic font path resolution)



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# File 'lib/pdf/reader/width_calculator/built_in.rb', line 13

def initialize(filename)
  @metadata = {}
  @char_metrics = {}
  @char_metrics_by_code = {}
  @kern_pairs = []
  File.open(filename) do |file|
    mode = :meta
    file.each_line do |line|
      case(line)
      when /^StartFontMetrics/ ; mode = :meta
      when /^StartCharMetrics/ ; mode = :char_metrics
      when /^EndCharMetrics/ ; mode = :meta
      when /^StartKernData/ ; mode = :kern_data
      when /^StartKernPairs/ ; mode = :kern_pairs
      when /^EndKernPairs/ ; mode = :kern_data
      when /^EndKernData/ ; mode = :meta
      else
        case(mode)
        when :meta
          if match = line.match(/^([\w]+) (.*)$/)
            @metadata[match[1]] = match[2]
          end
        when :char_metrics
          metrics = {}
          metrics[:charcode] = match[1].to_i if match = line.match(/C (-?\d+) *?;/)
          metrics[:wx] = match[1].to_i if match = line.match(/WX (-?\d+) *?;/)
          metrics[:name] = match[1] if match = line.match(/N ([.\w]+) *?;/)
          if match = line.match(/B (-?\d+) (-?\d+) (-?\d+) (-?\d+) *?;/)
            metrics[:boundingbox] = [match[1].to_i, match[2].to_i, match[3].to_i, match[4].to_i]
          end
          @char_metrics[metrics[:name]] = metrics if metrics[:name]
          @char_metrics_by_code[metrics[:charcode]] = metrics if metrics[:charcode] && metrics[:charcode] > 0
        when :kern_pairs
          if match = line.match(/^KPX ([.\w]+) ([.\w]+) (-?\d+)$/)
            @kern_pairs << [match[1], match[2], match[3].to_i]
          end
        end
      end
    end
  end
end

Instance Attribute Details

#char_metrics_by_code ⇒ Object (readonly)

Returns the value of attribute char_metrics_by_code.



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# File 'lib/pdf/reader/width_calculator/built_in.rb', line 10

def char_metrics_by_code
  @char_metrics_by_code
end