Macramoji

A slack-centric programming language for altering emoji

How it works

Macramoji parses a simple functional programming language for emoji, where function names can either precede or follow the parenthesis and emoji are slack-style (i.e. beginning and ending with a :). For example:

(dealwithit(:rage1:, :kamina-glasses:))splosion

This produces the following gif (assuming you have kamina-glasses):

Defined macros

• dealwithit(<base> [, glasses]) - Draw sunglasses that descend onto the base emoji. Optionally, provide the emoji for the glasses that will be used.
• (<base>)splosion - Draw the base emoji followed by an explosion
• firstframe(<base>) - Take the first frame of base
• lastframe(<base>) - Take the last frame of base
• (<base>)intensifies - Make the last frame of base shake intensely
• (<base>)skintone_1 - Colorize base in Fitzpatrick skin tone 1. Tones 1-6 are defined

Reference Implementation: Hubot script

This script allows you to message a hubot instance with the command emojify (dealwithit(:rage1:, :kamina-glasses:))splosion

macramoji = require 'macramoji'
refreshSeconds = 15 * 60 # refesh emoji list every 15 minutes
module.exports = (robot) ->
  emojiFetchFn = (callback) ->
    robot.adapter.client.web.emoji.list (err, result) ->
      return callback(err) if err
      callback(err, result.emoji)
  emojiStore = new macramoji.EmojiStore(emojiFetchFn, refreshSeconds)
  processor = new macramoji.EmojiProcessor(emojiStore, macramoji.defaultMacros)

  robot.respond /emojify (.*)/i, (res) ->
    emojiStr = res.match[1].trim()
    processor.process emojiStr, (slackResp) ->
      slackResp.respondHubot(res)

Defining Your Own Functions

Arbitrary emoji-processing functions are straightforward to add; they are GraphicsMagick (or ImageMagick) scripts. Their input arguments will be an array of paths and a callback function. The callback takes a single parameter -- an ImageResult. The ImageResult conveys the result (if successful), any error messages (if unsuccessful) and a set of ImageContainer objects for any temporary files created during the processing that would need to be cleaned up later.

What Macramoji guarantees

• your function will only be called if the input arguments successfully resolve to ImageResults
• all input image arguments will automatically be rescaled to the size of the smallest image

What Macramoji does not guarantee

• input animations may need to be coalesced
• no alpha channel is explicitly provided
• your function may not receive all the arguments it expects (in which case, you should return an ImageResult that holds an error message)

A basic exaple is greyscale which converts an emoji to greyscale:

imageTransform = (require 'macramoji').imageTransform

greyscaleMacro = (paths, callback) ->
  greyWorkFn = (inputGmObject) ->
    inputGmObject.modulate(100, 0) # http://aheckmann.github.io/gm/docs.html#modulate
  imageTransform.resultFromGM gm(paths[0]), greyWorkFn, callback

# assume processor = new macramoji.EmojiProcessor as above
processor.addMacro("greyscale", greyscaleMacro)

You are encouraged to contribute functions that you write back to this project by adding them to defaultMacros.coffee.

Known Issues

TODO

• Check that proper cleanup is happening
• Enable slack reponses without hubot

Author

Macramoji was written by Ian Katz in 2017, after realizing that making explosion gifs for literally hundreds of emoji just wasn't scalable.