lemniscate.lua

-- lemniscate
-- enc3 -> loop length
-- k1 + k2 -> toggle record
-- k2 -> toggle play
-- k1 + k3 -> stop all
-- k3 -> program select
-- k1 + k2 + k3 -> clear buffer

local util = require('util')
local Parameters = include('lib/parameters')

engine.name = 'Lemnisc8'

local ASSET_PATH = '/home/we/dust/code/lemniscate/assets/bg_frames/'
local MAX_PROGRAM_LENGTH = 87
local MIN_PROGRAM_LENGTH = 1
local MAX_TAPE_VISUALIVATION_WIDTH = 24
local MIN_TAPE_VISUALIZATION_WIDTH = MAX_TAPE_VISUALIVATION_WIDTH / (MAX_PROGRAM_LENGTH * 4)
local MAX_BG_FRAMES = 6
local PROGRAM_CELL_DIMENSIONS = {3, 14}
local PROGRAM_CELLS = {
  {74, 26},
  {78, 26},
  {82, 26},
  {86, 26}
}

local alt = false
local bg_frame = 1
local clear_time = 0.75
local frame_clock = nil
local parameters = nil
local playing = 0
local position = 1
local program = 1
local program_length = 10
local rec_amp = 1.0
local recording = 0
local shift = false
local tape_length = 40
local tape_visualization_width = 8
local throttle_keys = false

local function _bin_to_bool(v)
  return v == 1
end

local function _animate_background()
  if _bin_to_bool(playing) or _bin_to_bool(recording) then
    bg_frame = util.wrap(bg_frame + 1, 1, MAX_BG_FRAMES)
  end
end

local function _refresh_position(i, pos)
  position = math.floor(pos)
end

local function _set_head_position()
  for i = 1, 2 do
    softcut.position(i, position)
  end

  softcut.voice_sync(2, 1, 0)
end

local function _set_tape_width()
  tape_visualization_width = math.floor(tape_length * MIN_TAPE_VISUALIZATION_WIDTH) + 6
end

local function init_animation()
  frame_clock = metro.init(_animate_background, 1/12)
  frame_clock:start()
end

local function init_audio()
  audio.rev_off()
  audio.comp_off()
  audio.level_adc_cut(1)
  audio.level_eng_cut(0)
  audio.level_tape_cut(0)
end

local function init_params()
  local set_param = {
    filter_cutoff = function(val)
      for i = 1, 2 do
        softcut.pre_filter_fc(i, val)
      end
    end,
    play_amp = function(val)
      for i = 1, 2 do
        softcut.level(i, val)
      end
    end,
    preserve_amp = function(val)
      for i = 1, 2 do
        softcut.pre_level(i, val)
      end
    end,
    source_amp = function(val)
      for i = 1, 2 do
        softcut.level_input_cut(i, 1, val)
      end
    end
  }

  Parameters.init(set_param)
end 

local function init_softcut()
  softcut.buffer_clear()
  softcut.event_position(_refresh_position)
  for i = 1, 2 do
    softcut.enable(i, 1)
    softcut.buffer(i, i)
    softcut.pre_filter_fc(i, params:get('filter_cutoff'))
    softcut.pre_filter_dry(i, 0.5)
    softcut.pre_filter_lp(i, 1)
    softcut.level(i, params:get('play_amp'))
    softcut.level_slew_time(i, 0)
    softcut.loop(i, 1)
    softcut.loop_start(i, 1)
    softcut.loop_end(i, tape_length)
    softcut.pre_level(i, params:get('preserve_amp'))
    softcut.rec_level(i, rec_amp)
    softcut.position(i, position)
    softcut.level_input_cut(i, 1, params:get('source_amp'))
  end
end

local function get_program_offset()
  return (program - 1) * program_length
end

local function toggle_play()
  playing = util.wrap(playing + 1, 0, 1)


  if _bin_to_bool(playing) then
    engine.play('eject', params:get('lem_skeuo_amp'))
  else
    engine.play('insert', params:get('lem_skeuo_amp'))
  end

  for i = 1, 2 do
    softcut.play(i, playing)
  end

  softcut.voice_sync(2, 1, 0)
end

local function toggle_record()
  recording = util.wrap(recording + 1, 0, 1)

  engine.play('record', params:get('lem_skeuo_amp'))

  for i = 1, 2 do
    softcut.rec(i, recording)
  end

  softcut.voice_sync(2, 1, 0)
end

local function clear_all()
  throttle_keys = true

  clock.run(function()
    clock.sleep(clear_time)
    throttle_keys = false
  end)
  
  alt = false
  shift = false
  softcut.buffer_clear()
end

local function stop_all()
  for i = 1, 2 do
    softcut.play(i, 0)
    softcut.rec(i, 0)
  end

  engine.play('eject', params:get('lem_skeuo_amp'))

  position = 1
  program = 1
  playing = 0
  recording = 0
  _set_head_position()
end

local function program_select(n)
  local segment_position = position - get_program_offset()

  engine.play('program_select', params:get('lem_skeuo_amp'))

  if n then
    program = n
  else
    program = util.wrap(program + 1, 1, 4)
  end

  position = segment_position + get_program_offset()
  _set_head_position()
end

local function refresh_background()
  screen.display_png(ASSET_PATH..bg_frame..'.png', 0, 0)
end

local function format_time(s)
  local minutes = math.floor(s / 60)
  local seconds = s % 60
  return ''..((minutes ~= 0 and minutes..'\'') or '')..seconds..'"'
end

local function refresh_foreground()
  -- Variable Program Elements
  local x, y = PROGRAM_CELLS[program][1], PROGRAM_CELLS[program][2]
  local width, height = PROGRAM_CELL_DIMENSIONS[1], PROGRAM_CELL_DIMENSIONS[2]
  local program_center = x + math.floor(width/2)
  local program_length_string = format_time(program_length)
  local program_length_string_center = math.floor(screen.text_extents(program_length_string) / 2)
  screen.rect(x, y, width, height)
  -- Above progrm viz info
  screen.font_face(25)
  screen.font_size(6)
  screen.move(program_center, y - 4)
  screen.line(program_center, y - 7)
  screen.line(90, y - 7)
  screen.line(100, y - 7)
  screen.move_rel(3, 2)
  screen.text(program)
  screen.move_rel(0, -8)
  screen.text_right('program')
  screen.move_rel(2, -2)
  screen.line_rel(program_length_string_center - 1, 0)
  screen.move_rel(1, 0)
  screen.line_rel(0, 14)
  screen.move(108, 34)
  screen.text(program_length_string)
  -- Below program viz info
  screen.font_face(21)
  screen.font_size(18)
  screen.move(program_center, y + height + 4)
  screen.line(program_center, y + height + 7)
  screen.line(90, y + height + 8)
  screen.line(100, y + height + 8)
  screen.move_rel(0, 6)
  if _bin_to_bool(recording) then
    screen.level(((position % 7) + 1) * 2)
    screen.font_face(21)
    screen.font_size(18)
    screen.text('•')
    screen.level(16)
  end
  if _bin_to_bool(playing) then
    screen.move_rel(_bin_to_bool(recording) and 0 or 4, -4)
    screen.font_face(1)
    screen.font_size(8)
    screen.text('▶')
  end
  screen.move(104, y + height + 19)
  screen.font_face(25)
  screen.font_size(6)
  screen.text(format_time(position))
  -- Tape length (fixed pos)
  screen.move(0, 32)
  screen.arc(0, 32, tape_visualization_width, 4, 6)
  screen.move(23, 34)
  screen.text(format_time(tape_length))
  screen.move(23, 36)
  screen.line_rel(tape_visualization_width, 0)
end

local function refresh_program()
  if _bin_to_bool(playing) or _bin_to_bool(recording) then
    softcut.query_position(1)
    program = math.ceil(position / program_length)
  end
end

local function set_tape_length(d)
  program_length = util.clamp(program_length + d, MIN_PROGRAM_LENGTH, MAX_PROGRAM_LENGTH)
  tape_length = 4 * program_length
  
  for i = 1, 2 do
    -- Loop should be inclusive of final second
    softcut.loop_end(i, tape_length + 1)
  end

  position = util.clamp(position, 1, program_length)
  _set_tape_width()
  _set_head_position()  
end

function init()
  init_params()
  init_animation()
  init_audio()
  init_softcut()
  redraw()
end

function enc(e, d)
  if e == 3 then
    set_tape_length(d)
  end
end

function key(k, z)
  if not throttle_keys then
    if k == 1 and z == 1 then
      shift = true
    elseif k == 1 and z == 0 then
      alt = false
      shift = false
    elseif k == 2 and z == 1 and shift then
      alt = true    
    elseif k == 2 and z == 0 and not shift then
      if _bin_to_bool(playing) and _bin_to_bool(recording) then
        toggle_record()
      end
      toggle_play()
    elseif k== 2 and z == 0 and shift then
      if not _bin_to_bool(playing) and not _bin_to_bool(recording) then
        toggle_play()
      end
      toggle_record()
    elseif k == 3 and z == 0 and not shift then
      program_select()
    elseif k == 3 and z == 0 and shift and not alt then
      stop_all()
    elseif k == 3 and z == 1 and shift and alt then
      clear_all()
    end
  end
end

function redraw()
  screen.clear()
  refresh_program()
  refresh_background()
  refresh_foreground()
  screen.stroke()
  screen.update()
end

function refresh()
  redraw()
end