testing a slowdown Lua script for VCV Rack

slowdown.lua

-- max buffer length in seconds
length = 10

addLabel(50, 125, "Input", 20)
addLabel(50, 165, "Trigger", 20)
addLabel(50, 205, "Delay", 20)
addLabel(190, 125, "Output", 20)
input = addInput(20, 120)
trigger = addInput(20, 160)
delay = addInput(20, 200)
output = addOutput(160, 120)
lastSampleRate = 0
lastTriggered = 0
triggered = 0

function initBuffer()
	buffer = {}
	samples = length * sampleRate
	for i=0,samples-1 do buffer[i] = 0 end
	lastSampleRate = sampleRate
	inIndex = 0
	outIndex = 0
	print("buffer initializd, size: " .. samples .. " samples")
end

function process()
	-- init buffer on sample rate changes and on start
	if lastSampleRate ~= sampleRate then
		initBuffer()
	end
	
	-- check trigger (schmitt-trigger implementation with 1 V hysteresis)
	v = getVoltage(trigger)
	v2 = 0
	if triggered == 1 then
		if v < 2 then
			triggered = 0
		end
	else
		if v > 3 then
			triggered = 1
		end
	end
	if lastTriggered == 0 and triggered == 1 then
		inIndex = 0
		outIndex = 0
	end
	lastTriggered = triggered
	
	-- store input voltage
	buffer[inIndex] = getVoltage(input)
	
	-- delayed output 
	setVoltage(output, buffer[math.floor(outIndex)])
	
	-- increment index
	inIndex = inIndex + 1
	if inIndex >= samples then
		inIndex = 0
	end
	outIndex = outIndex + 1 / math.abs(getVoltage(delay))
	if outIndex >= samples then
		outIndex = 0
	end
end