Adagio arc mod script

{ Compiled on Mon Jan  4 21:52:36 2021 }
on init
  make_perfview
  set_script_title("SL Arcs Mods")
  set_ui_height_px(256)
  message("")
  declare $i := 0
  declare $note_id := 0
  declare $prev_pos := 0
  declare $keys_down := 0
  declare $offset_calc := 0
  make_persistent($offset_calc)
  declare ui_knob $kAttack(0, 1000000, 1)
  make_persistent($kAttack)
  set_text($kAttack,"Attack")
  set_knob_unit($kAttack,$KNOB_UNIT_MS)
  $kAttack := get_engine_par($ENGINE_PAR_ATTACK,0,0,-1)
  set_knob_label($kAttack,get_engine_par_disp($ENGINE_PAR_ATTACK,0,0,-1))
  declare ui_knob $kRelease(0, 1000000, 1)
  make_persistent($kRelease)
  set_text($kRelease,"Release")
  set_knob_unit($kRelease,$KNOB_UNIT_MS)
  $kRelease := get_engine_par($ENGINE_PAR_RELEASE,0,0,-1)
  set_knob_label($kRelease,get_engine_par_disp($ENGINE_PAR_RELEASE,0,0,-1))
  declare ui_knob $kOffset(0, 1000000, 10000)
  make_persistent($kOffset)
  set_text($kOffset,"Offset")
  set_knob_unit($kOffset,$KNOB_UNIT_PERCENT)
  declare ui_button $bLegato
  make_persistent($bLegato)
  set_text($bLegato,"Poly Legato")
end on

on ui_control($kAttack)
  $i := 0
  while ($i<$NUM_GROUPS)
    set_engine_par($ENGINE_PAR_ATTACK,$kAttack,$i,0,-1)
    inc($i)
  end while
  set_knob_label($kAttack,get_engine_par_disp($ENGINE_PAR_ATTACK,0,0,-1))
end on

on ui_control($kRelease)
  $i := 0
  while ($i<$NUM_GROUPS)
    set_engine_par($ENGINE_PAR_RELEASE,$kRelease,$i,0,-1)
    inc($i)
  end while
  set_knob_label($kRelease,get_engine_par_disp($ENGINE_PAR_RELEASE,0,0,-1))
end on

on ui_control($kOffset)
  $offset_calc := $kOffset
end on

on note
  ignore_event($EVENT_ID)
  if ($bLegato=1)
    if ($keys_down>0)
      $prev_pos := get_event_par($note_id,$EVENT_PAR_PLAY_POS)
    else
      $prev_pos := $offset_calc
    end if
  else
    $prev_pos := $offset_calc
  end if
  $note_id := play_note($EVENT_NOTE,$EVENT_VELOCITY,$prev_pos,-1)
  inc($keys_down)
  inc($keys_down)
end on

on release
  dec($keys_down)
  if ($keys_down<0)
    $keys_down := 0
  end if
end on