LibGDX Emoji support (glyphs injection technique)

1. Just drop the EmojiSupport.java into your project
2. Copy the emoji atlas files into your assets folder
3. Add code support

...
 EmojiSupport emojiSupport;   // global instance
 ...
 // Create instance, load emojis and add to existing font(s)
 emojiSupport= new EmojiSupport();
 emojiSupport.Load(Gdx.files.internal("data/emojis25.atlas"));
 emojiSupport.AddEmojisToFont(skin.getFont("default-font"));
 ...
 // Filter/translate emojis before display
 Label label1 = new Label(emojiSupport.FilterEmojis(str), skin);

Current limitation: The Glyph class uses a char as index so should need a lot of work to change all the logic (ex: line-breaks) to use multi-chars (unicode emojis). So the solution is to "inject" new Glyphs (from another Texture page) to the current BitmapFont using a special char index ( > 0xB000). When a string includes an Emoji Code, for example: 😎 (\ud83d\ude0e) [two chars] is replaced by a char 0xB001 [one char] that points to its emoji Glyph texture region.

• Only one emoji.png (Atlas) file needed (can be added to all fonts in the App)
• Don't messes the GlyphsRun, BitmapFonts, BitmapFontCache, etc core Gdx classes
• You can add only your "preferred" emojis (reduce space)
• You can use emojis at greater or lower resolutions (will scale to the font size)
• No cpu-cost in runtime (it's exactly the same as any other char)
• Also supported in FreeType run-time generated fonts
• Supports multi-pages emojis (emoji atlas with more than one png).
• Tested in iOS (RoboVM).

• Always need to call to FilterEmojis to translate double-char codes (unicode) to 0xB000+i chars (This may not be a drawback as only in very few places you need to use texts with Emojis)
• Text setColor() functions not supported (only in b&w emojis).

• Not tested in TextAreas.
• Flags emojis and some other emojis are missing
• Not supported skin-tone modifiers

All Unicode chars : https://en.wikipedia.org/wiki/List_of_Unicode_characters

Tables : https://www.utf8-chartable.de/unicode-utf8-table.pl

Conversions : https://stackoverflow.com/questions/33320058/converting-unicode-symbols-to-their-code

Java surrogate chars : https://docs.oracle.com/javase/8/docs/api/java/lang/Character.html

Special char FE0F : https://www.fileformat.info/info/unicode/char/fe0f/index.htm

Emoji images source : https://github.com/stv0g/unicode-emoji

Inspirated in : https://github.com/taluks/libgdx-emodji

• v.1.1 - Support for multi pages emojis (bugfix)
• v.1.0 - Initial release

Color Emojis 25x25 https://github.com/stv0g/unicode-emoji/tree/master/apple

Packed with TexturePacker : 821 emojis , 1.32 Mb size

Black and White Emojis 25x25 https://github.com/stv0g/unicode-emoji/tree/master/symbola

Packed with TexturePacker : 789 emojis , 0.36 Mb size