ZNTEmoji.sh

#!/bin/bash
#
# License:
# * Copyright (C) 2014 Héctor Molinero Fernández
# *
# * This program is free software: you can redistribute it and/or modify
# * it under the terms of the GNU General Public License as published by
# * the Free Software Foundation, either version 3 of the License, or
# * (at your option) any later version.
# *
# * This program is distributed in the hope that it will be useful,
# * but WITHOUT ANY WARRANTY; without even the implied warranty of
# * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# * GNU General Public License for more details.
# *
# * You should have received a copy of the GNU General Public License
# * along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# Dependencies: 
# * fonttools
# * git
# * ruby
#

#=======================================#
infoMsg() {
    echo -e "\e[1;33m + \e[1;32m$1 \e[0m"
}

#=======================================#
infoMsg "Removing previous files..."
rm -rf ./emoji ./emoji-temp ./ZNTEmoji.js ./ZNTEmoji.css

#=======================================#
infoMsg "Creating a new temporary directory..."
mkdir ./emoji-temp
cd ./emoji-temp

#=======================================#
infoMsg "Cloning noto-fonts Git repository..."
git clone https://android.googlesource.com/platform/external/noto-fonts

#=======================================#
infoMsg "Converting NotoColorEmoji.ttf to TTX format..."
ttx ./noto-fonts/NotoColorEmoji.ttf
cp ./noto-fonts/NotoColorEmoji.* ./

#=======================================#
infoMsg "Extracting font images using \"emoji_extractor.rb\"..."
cat > ./emoji_extractor.rb <<'EOF'
# https://github.com/zant95/emoji-extractor/blob/master/emoji_extractor.rb
# stolen largely from http://www.ruby-forum.com/topic/140784

require 'stringio'
require 'fileutils'

def extract_chunk(input, output)
    lenword = input.read(4)
    length = lenword.unpack('N')[0]
    type = input.read(4)
    data = length>0 ? input.read(length) : ""
    crc = input.read(4)
    return nil if length<0 || !(('A'..'z')===type[0,1])
    #return nil if validate_crc(type+data, crc)
    output.write lenword
    output.write type
    output.write data
    output.write crc
    return [type, data]
end

def extract_png(input)
    buf = StringIO.new
    hdr = input.read(8)
    raise "Not a PNG File" if hdr[0,4]!= "\211PNG"
    raise "file not in binary mode" if hdr[4,4]!="\r\n\032\n"
    buf.write(hdr)

    height, width = 0, 0

    loop do
        chunk_type, chunk_data = extract_chunk(input,buf)
        height, width = chunk_data.unpack('NN') if chunk_type == 'IHDR'
        break if    chunk_type.nil? || chunk_type == 'IEND'
    end

    FileUtils.mkdir_p(dir = "images/#{height}x#{width}")
    if @prev != dir
        @n = 0
        @prev = dir
    end

    buf.rewind
    ofp = File.new("#{dir}/#{@n+=1}.png","wb")
    ofp.write buf.read
    ofp.close
end

ttf = File.new("./NotoColorEmoji.ttf","rb")
ttf_data = ttf.read

pos = 0
while m = /\211PNG/.match(ttf_data[pos..-1])
    raise "no PNG found" if !m
    pos += m.begin(0) + 1
    ttf.seek(pos-1)

    extract_png(ttf)
end
EOF

ruby ./emoji_extractor.rb

#=======================================#
infoMsg "Creating ZNTEmoji JavaScript file..."
cat > ../ZNTEmoji.js <<'EOF'
var ZNTEmoji = {
    version: '1.0.0',

    replace: function(string) {
        'use strict';

        return string
            // Encode astral symbols.
            .replace(/[\uD800-\uDBFF][\uDC00-\uDFFF]/g, function($0) {
                // http://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
                var high = $0.charCodeAt(0),
                    low = $0.charCodeAt(1),
                    codePoint = (high - 0xD800) * 0x400 + low - 0xDC00 + 0x10000,
                    astralSymbol = codePoint.toString(16);

                var emojiElement = document.createElement('i');
                    emojiElement.className = 'ZNTEmoji ZNTEmoji-uni' + astralSymbol;

                return emojiElement.outerHTML;
            });
    }
};
EOF

#=======================================#
infoMsg "Creating ZNTEmoji stylesheet file..."
cat > ../ZNTEmoji.css <<'EOF'
.ZNTEmoji {
    display: inline-block;
    vertical-align: middle;
    width: 26px;
    height: 24px;
    background-size: 26px 24px;
    background-color: transparent;
    background-repeat: no-repeat;
}

EOF

#=======================================#
infoMsg "Renaming each image with its corresponding Unicode character and adding it to the stylesheet..."

# 136x128 or 68x64
for FILE in ./images/136x128/*.png
do
    ID=$(basename $FILE .png)
    NAME=$(grep -o -P "(?<=<GlyphID id=\"$ID\" name=\").*(?=\"/>)" NotoColorEmoji.ttx)

    echo ".ZNTEmoji-$NAME{background-image:url(emoji/$NAME.png);}" >> ../ZNTEmoji.css

    mv -fv $FILE ./images/136x128/$NAME.png
done

#=======================================#
infoMsg "Moving images to \"emoji\" directory..."
mv -fv ./images/136x128 ../emoji

#=======================================#
infoMsg "Exiting from temporary directory and deleting it..."
cd ../
rm -rf ./emoji-temp

exit 0

Incredible work and use of the command line my friend.