src/RMCA/Translator/Message.hs

   1 module RMCA.Translator.Message where
   2
   3 import           RMCA.Semantics
   4 import qualified Sound.MIDI.Message               as Message
   5 import qualified Sound.MIDI.Message.Channel       as Channel
   6 import qualified Sound.MIDI.Message.Channel.Voice as Voice
   7
   8 -- We might want to move that to Semantics.
   9 type SampleRate = Int
  10
  11 type RawMessage = Message.T
  12
  13 type MidiVoice = Voice.T
  14
  15 type Channel = Channel.Channel
  16
  17 type ControllerIdx = Voice.Controller
  18
  19 type Frames = Int
  20
  21 -- Each channel is linked to a particular translation signal function
  22 -- itself linked to a particular layer. Therefore we will dispose of
  23 -- the channel number as soon as possible.
  24 ---
  25 -- /!\ This is dangerous as it only treats unipolar control values.
  26 data Message = NoteOn  Channel Pitch Strength
  27              | NoteOff Channel Pitch Strength
  28              | Control Channel ControllerIdx UCtrl
  29   deriving(Show)
  30
  31 getChannel :: Message -> Int
  32 getChannel (NoteOn c _ _) = Channel.fromChannel c
  33 getChannel (NoteOff c _ _) = Channel.fromChannel c
  34 getChannel (Control c _ _) = Channel.fromChannel c
  35
  36 makeChannel :: Int -> Channel
  37 makeChannel = Channel.toChannel
  38
  39 -- Function to go back and forth with the representations of pitches,
  40 -- as they are different in our model and in the Jack API model.
  41 fromRawPitch :: Voice.Pitch -> Pitch
  42 fromRawPitch p = Pitch $ Voice.fromPitch p
  43
  44 toRawPitch :: Pitch -> Voice.Pitch
  45 toRawPitch (Pitch p) = Voice.toPitch p
  46
  47
  48 isNoteOn :: Message -> Bool
  49 isNoteOn NoteOn {} = True
  50 isNoteOn _ = False
  51
  52 isNoteOff :: Message -> Bool
  53 isNoteOff NoteOff {} = True
  54 isNoteOff _ = False
  55
  56 isControl :: Message -> Bool
  57 isControl Control {} = True
  58 isControl _ = False
  59
  60 switchOnOff :: Message -> Message
  61 switchOnOff (NoteOn  c p v) = NoteOff c p v
  62 switchOnOff (NoteOff c p v) = NoteOn  c p v
  63 switchOnOff m = error $ "The message " ++ show m ++ " is not a note message"
  64
  65 fromRawMessage :: RawMessage -> Maybe Message
  66 fromRawMessage (Message.Channel (Channel.Cons c
  67                                  (Channel.Voice (Voice.NoteOn  p v)))) =
  68   Just $ NoteOn  c (fromRawPitch p) (toUCtrl $ Voice.fromVelocity v)
  69 fromRawMessage (Message.Channel (Channel.Cons c
  70                                  (Channel.Voice (Voice.NoteOff p v)))) =
  71   Just $ NoteOff c (fromRawPitch p) (toUCtrl $ Voice.fromVelocity v)
  72 fromRawMessage (Message.Channel (Channel.Cons c
  73                                  (Channel.Voice (Voice.Control n v)))) =
  74   Just $ Control c n (toUCtrl v)
  75 fromRawMessage _ = Nothing
  76
  77 toRawMessage :: Message -> RawMessage
  78 toRawMessage (NoteOn  c p v) =
  79   Message.Channel $ Channel.Cons c
  80   (Channel.Voice $ Voice.NoteOn  (toRawPitch p) (Voice.toVelocity $ fromUCtrl v))
  81 toRawMessage (NoteOff c p v) =
  82   Message.Channel $ Channel.Cons c
  83   (Channel.Voice $ Voice.NoteOff (toRawPitch p) (Voice.toVelocity $ fromUCtrl v))
  84 toRawMessage (Control c n v) =
  85   Message.Channel (Channel.Cons c
  86                     (Channel.Voice (Voice.Control n (fromUCtrl v))))