Controlling 3 Note Generator in Helix

Windows/Mac MIDI Machines
1

I just wanted to share my script for creating an interface where Midi Guitar 2 can send note values to the 3 Note Generator in the Line 6 Helix. Unfortunately, the Helix does not take midi note information for the 3 Note Generator, so I had to convert the pitch values to CC messages to the corresponding Note and Octaves in the Helix.

The appropriate MIDI CC configurations are set up on the line 6 custom tone:

Here’s the code.

noteArray = {} -- This holds 0-n notes being played simultaneously
ccNoteArray = {4, 5, 6, 7, 8, 9 } -- Which CC this will send for note information
ccOctaveArray = {10,11,12,13,14,15} -- Which CC this will send for octave information
ccLevelsArray = {16,17,18,19,20,21} -- Which CC this will send for volume information

function OnNote(channel, pitch, velocity)
	if(velocity>0) then
		table.insert(noteArray,pitch)
	else
		-- If there is a dead note, clean up
		local currentIndex = indexOf(noteArray,pitch)
	
		table.remove(noteArray,currentIndex,1)
	end

	Note(channel, pitch, velocity) -- This can be removed if passthrough midi note is not needed
	outputNotes()
end

function convertNoteToHelixVelocity(inputNote)
	local currentNote = inputNote%12

	return math.floor(((currentNote+1)/12)*127)
end

function convertNoteToOctave(inputOctave)

	return math.floor((inputOctave/8)*127)
end

function getNoteOctave(inputNote)

	return math.floor(inputNote/12)
end

function outputNotes()

	for i=1,#(noteArray) do
		Control(1,ccNoteArray[i],convertNoteToHelixVelocity(noteArray[i]))
		Control(1,ccOctaveArray[i],convertNoteToOctave(getNoteOctave(noteArray[i])))
		Control(1,ccLevelsArray[i],64) --volume 5

	end

	-- For any unused oscillators, make sure to mute them
	for i=#(noteArray)+1,#(ccLevelsArray) do
		Control(1,ccLevelsArray[i],0)
	end

end

function indexOf(array,value)
	for i,v in ipairs(array) do
		if v == value then
			return i
		end
	end

	return nil
end



function OnStart(info)
	-- assign a description to be displayed in the header
	info.description = "Convert guitar notes into something the Helix can process with the 3 Note Generator"
	info.link = "http://jamorigin.com/midi-machine"
end