experimenting with the idea of a declarative style midi processing chain

test_chain_voice.lua

engine.name = 'PolySub'

local midi = require 'ngwese/midi_process'

chain = midi.Chain{
  midi.Logger(),
  midi.Held(),
  midi.Pattern{
    pattern = 'as-played'
  },
  midi.Arp{
    octaves = 1
  },
  midi.Logger(),
  midi.Behavior{
    note_on = function(ch, num, vel)
      local pitch = midi.to_hz(num)
      engine.start(midi.to_id(ch, num), pitch)
    end,
  
    note_off = function(ch, num, vel)
      engine.stop(midi.to_id(ch, num))
    end,
  
    pitch_bend = function(ch, value)
      local v = midi.to_bend_range(value)
      engine.shape(math.abs(v) * 0.7)
    end,
  
    channel_pressure = function(ch, value)
      local f = value / 127
      engine.noise(f * 0.2)
      engine.fgain((f * 0.7) + 0.2)
      engine.timbre(f * 0.7)
    end,
  },
}

clock = midi.Clock{
  interval = midi.bpm_to_sec(120, 16),
  chain = chain,
}

input1 = midi.Input{
  device = "AXIS-64 USB Keyboard",
  chain = chain,
}

input2 = midi.Input{
  device = "TOUCHE",
  chain = chain,
}

init = function()
  midi.init()

  -- configure engine
  engine.level(0.2)
  engine.stopAll()
  
  -- register parameters
  params:add_control("shape", controlspec.new(0,1,"lin",0,0,""))
  params:set_action("shape", function(x) engine.shape(x) end)

  params:add_control("timbre", controlspec.new(0,1,"lin",0,0.5,""))
  params:set_action("timbre", function(x) engine.timbre(x) end)

  params:add_control("noise", controlspec.new(0,1,"lin",0,0,""))
  params:set_action("noise", function(x) engine.noise(x) end)

  params:add_control("cut", controlspec.new(0,32,"lin",0,8,""))
  params:set_action("cut", function(x) engine.cut(x) end)

  params:add_control("fgain", controlspec.new(0,6,"lin",0,0,""))
  params:set_action("fgain", function(x) engine.fgain(x) end)

  params:add_control("cutEnvAmt", controlspec.new(0,1,"lin",0,0,""))
  params:set_action("cutEnvAmt", function(x) engine.cutEnvAmt(x) end)

  params:add_control("detune", controlspec.new(0,1,"lin",0,0,""))
  params:set_action("detune", function(x) engine.detune(x) end)

  params:add_control("ampAtk", controlspec.new(0.01,10,"lin",0,0.05,""))
  params:set_action("ampAtk", function(x) engine.ampAtk(x) end)

  params:add_control("ampDec", controlspec.new(0,2,"lin",0,0.1,""))
  params:set_action("ampDec", function(x) engine.ampDec(x) end)

  params:add_control("ampSus", controlspec.new(0,1,"lin",0,1,""))
  params:set_action("ampSus", function(x) engine.ampSus(x) end)

  params:add_control("ampRel", controlspec.new(0.01,10,"lin",0,1,""))
  params:set_action("ampRel", function(x) engine.ampRel(x) end)

  params:add_control("cutAtk", controlspec.new(0.01,10,"lin",0,0.05,""))
  params:set_action("cutAtk", function(x) engine.cutAtk(x) end)

  params:add_control("cutDec", controlspec.new(0,2,"lin",0,0.1,""))
  params:set_action("cutDec", function(x) engine.cutDec(x) end)

  params:add_control("cutSus", controlspec.new(0,1,"lin",0,1,""))
  params:set_action("cutSus", function(x) engine.cutSus(x) end)

  params:add_control("cutRel", controlspec.new(0.01,10,"lin",0,1,""))
  params:set_action("cutRel", function(x) engine.cutRel(x) end)

end

cleanup = function()
  midi.cleanup()
end