Add bin and edit workflow

bin/gems/ttfunk-1.8.0/lib/ttfunk/subset/unicode_8bit.rb

@@ -0,0 +1,99 @@
+# frozen_string_literal: true
+
+require 'set'
+require_relative 'base'
+
+module TTFunk
+  module Subset
+    # An 8-bit Unicode-based subset. It can include any Unicode character but
+    # limits number of characters so that the could be encoded by a single byte.
+    class Unicode8Bit < Base
+      # @param original [TTFunk::File]
+      def initialize(original)
+        super
+        @subset = { 0x20 => 0x20 }
+        @unicodes = { 0x20 => 0x20 }
+        @next = 0x21 # apparently, PDF's don't like to use chars between 0-31
+      end
+
+      # Is this a Unicode-based subset?
+      #
+      # @return [true]
+      def unicode?
+        true
+      end
+
+      # Get a mapping from this subset to Unicode.
+      #
+      # @return [Hash{Integer => Integer}]
+      def to_unicode_map
+        @subset.dup
+      end
+
+      # Add a character to subset.
+      #
+      # @param character [Integer] Unicode codepoint
+      # @return [void]
+      def use(character)
+        unless @unicodes.key?(character)
+          @subset[@next] = character
+          @unicodes[character] = @next
+          @next += 1
+        end
+      end
+
+      # Can this subset include the character?
+      #
+      # @param character [Integer] Unicode codepoint
+      # @return [Boolean]
+      def covers?(character)
+        @unicodes.key?(character) || @next < 256
+      end
+
+      # Does this subset actually has the character?
+      #
+      # @param character [Integer] Unicode codepoint
+      # @return [Boolean]
+      def includes?(character)
+        @unicodes.key?(character)
+      end
+
+      # Get character code for Unicode codepoint.
+      #
+      # @param character [Integer] Unicode codepoint
+      # @return [Integer]
+      def from_unicode(character)
+        @unicodes[character]
+      end
+
+      # Get `cmap` table for this subset.
+      #
+      # @return [TTFunk::Table::Cmap]
+      def new_cmap_table
+        @new_cmap_table ||=
+          begin
+            mapping =
+              @subset.each_with_object({}) do |(code, unicode), map|
+                map[code] = unicode_cmap[unicode]
+                map
+              end
+
+            # since we're mapping a subset of the unicode glyphs into an
+            # arbitrary 256-character space, the actual encoding we're
+            # using is irrelevant. We choose MacRoman because it's a 256-character
+            # encoding that happens to be well-supported in both TTF and
+            # PDF formats.
+            TTFunk::Table::Cmap.encode(mapping, :mac_roman)
+          end
+      end
+
+      # Get the list of Glyph IDs from the original font that are in this
+      # subset.
+      #
+      # @return [Array<Integer>]
+      def original_glyph_ids
+        ([0] + @unicodes.keys.map { |unicode| unicode_cmap[unicode] }).uniq.sort
+      end
+    end
+  end
+end