midi example added

examples/midi/README.md

@@ -0,0 +1,22 @@
+## About/Requirements
+
+A simple demonstration showing how to use a midi controller with this API. Specifically, this script binds the sliders of a Korg NanoKontrol2 to the 8 input strips of gainlayer 0. 
+
+In order to run this example script you will need to have setup Voicemeeter with a midi device in Menu->Midi Mapping.
+
+This script was written for and tested with a Korg NanoKontrol2 configured in CC mode. The slider CC numbers were increased by 1, as shown:
+
+![Image of Korg NanoKontrol2 Software](./img/nanokontrolsoftware.png)
+
+## Use
+
+First ensure Voicemeeter Potato version is launched. Then Press SEL for bus0 (A1).
+
+Move the NanoKontrol2 sliders and watch the strip sliders move.
+
+## Resources
+
+If you want to know how to setup the NanoKontrol2 for CC mode check the following resources.
+
+-   [Korg NanoKontrol2 Manual](https://www.korg.com/us/support/download/manual/0/159/1912/)
+-   [CC Mode Info](https://i.korg.com/uploads/Support/nanoKONTROL2_PG_E1_634479709631760000.pdf)

examples/midi/main.rb

@@ -0,0 +1,35 @@
+require_relative "../../lib/voicemeeter"
+
+class Main
+  GAINLAYER = 0
+
+  def initialize(vm)
+    @vm = vm
+    @vm.callback.register(self)
+  end
+
+  def run
+    puts "press <Enter> to quit"
+    loop { exit if gets.chomp.empty? }
+  end
+
+  def on_update(event)
+    if event == "midi"
+      current = @vm.midi.current
+      midi_handler(current, @vm.midi.get(current))
+    end
+  end
+
+  def midi_handler(i, val)
+    if i.between?(1, 8)
+      @vm.strip[i - 1].gainlayer[GAINLAYER].gain = (val * 72 / 127) - 60
+    end
+  end
+end
+
+
+if $0 == __FILE__
+  Voicemeeter::Remote.new(:potato, midi: true).run do |vm|
+    Main.new(vm).run
+  end
+end