launchpad-marquee/index.js

Use your Novation Launchpad as a scrolling marquee

'use strict'
const MidiInput = require('midi').input
const launchpadder = require('launchpadder')
const Launchpad = launchpadder.Launchpad
const marquee = require('./marquee')

function findLaunchpadPort (input) {
  for (var i = 0; i < input.getPortCount(); i++) {
    if (input.getPortName(0) === 'Launchpad S') {
      return i
    }
  }
  return null
}

function getColorWithDefault (color) {
  color = color.toUpperCase()

  if (launchpadder.Color.hasOwnProperty(color)) {
    return launchpadder.Color[color]
  }

  return launchpadder.Color.RED
}

module.exports = function launchpadMarquee (params) {
  const input = new MidiInput()
  const midiInputCount = input.getPortCount()

  if (!midiInputCount) {
    throw new Error('Unable to find MIDI input port')
  }

  const port = findLaunchpadPort(input)

  if (port === null) {
    throw new Error('Unable to find Launchpad S')
  }

  const pad = new Launchpad(port)
  const color = getColorWithDefault(params.color || '')

  return marquee(params, (marquee) => {
    marquee.forEach((row, y) => {
      row.forEach((light, x) => {
        const button = pad.getButton(x, y)
        light === 1 ? button.light(color) : button.dark()
      })
    })
  })
}