Reactogon/MIDI.hs

   1 module MIDI ( SampleRate
   2             , Pitch
   3             , toPitch
   4             , fromPitch
   5             , Velocity
   6             , Voice ( fromVoice
   7                     , toVoice
   8                     )
   9             , Note(..)
  10             ) where
  11
  12 import Sound.MIDI.Message.Channel.Voice ( fromPitch
  13                                         , toPitch
  14                                         )
  15 import qualified Sound.MIDI.Message.Channel.Voice as Voice
  16
  17 type SampleRate = Int
  18
  19 type Pitch = Voice.Pitch
  20 type Velocity = Voice.Velocity
  21
  22 class Voice a where
  23   fromVoice :: Voice.T -> Maybe a
  24   toVoice :: a -> Voice.T
  25
  26 data Note = NoteOn  Pitch Velocity
  27           | NoteOff Pitch Velocity
  28   deriving(Show)
  29
  30 instance Voice Note where
  31   fromVoice (Voice.NoteOn  p v) = Just $ NoteOn  p v
  32   fromVoice (Voice.NoteOff p v) = Just $ NoteOff p v
  33   fromVoice _ = Nothing
  34   toVoice (NoteOn  p v) = Voice.NoteOn  p v
  35   toVoice (NoteOff p v) = Voice.NoteOff p v