RCMA/Translator/Jack.hs

   1 {-# LANGUAGE Arrows #-}
   2
   3 -- Contains all the information and functions necessary to run a Jack
   4 -- port and exchange information through reactive values and Yampa.
   5 module RCMA.Translator.Jack ( jackSetup
   6                             ) where
   7
   8 import           Control.Applicative                 ((<**>))
   9 import qualified Control.Monad.Exception.Synchronous as Sync
  10 import qualified Control.Monad.Trans.Class           as Trans
  11 import qualified Data.Bifunctor                      as BF
  12 import           Data.CBMVar
  13 import qualified Data.EventList.Absolute.TimeBody    as EventListAbs
  14 import           Data.ReactiveValue
  15 import qualified Foreign.C.Error                     as E
  16 import           Hails.Yampa
  17 import           RCMA.Semantics
  18 import           RCMA.Translator.Filter
  19 import           RCMA.Translator.Message
  20 import           RCMA.Translator.RV
  21 import           RCMA.Translator.Translator
  22 import qualified Sound.JACK                          as Jack
  23 import qualified Sound.JACK.Exception                as JExc
  24 import qualified Sound.JACK.MIDI                     as JMIDI
  25
  26 rcmaName :: String
  27 rcmaName = "RCMA"
  28
  29 inPortName :: String
  30 inPortName = "input"
  31
  32 outPortName :: String
  33 outPortName = "output"
  34
  35 -- Starts a default client with an input and an output port. Doesn't
  36 -- do anything as such.
  37 jackSetup :: ReactiveFieldRead IO (LTempo, Int, [(Frames, RawMessage)])
  38           -> IO ()
  39 jackSetup boardInRV = Jack.handleExceptions $ do
  40   toProcessRV <- Trans.lift $ toProcess <$> newCBMVar []
  41   Jack.withClientDefault rcmaName $ \client ->
  42     Jack.withPort client outPortName $ \output ->
  43     Jack.withPort client inPortName  $ \input ->
  44     jackRun client (jackCallBack client input output toProcessRV boardInRV)
  45
  46 -- Loop that does nothing except setting up a callback function
  47 -- (called when Jack is ready to take new inputs).
  48 jackRun :: (JExc.ThrowsErrno e) =>
  49            Jack.Client
  50         -> (Jack.NFrames -> Sync.ExceptionalT E.Errno IO ())
  51         -> Sync.ExceptionalT e IO ()
  52 jackRun client callback =
  53   Jack.withProcess client callback $ do
  54   Trans.lift $ putStrLn $ "Started " ++ rcmaName
  55   Trans.lift $ Jack.waitForBreak
  56
  57 defaultTempo :: Tempo
  58 defaultTempo = 96
  59
  60 -- The callback function. It pumps value out of the input port, mix
  61 -- them with value coming from the machine itself and stuff them into
  62 -- the output port. When this function is not running, events are
  63 -- processed.
  64 jackCallBack :: Jack.Client
  65              -> JMIDI.Port Jack.Input
  66              -> JMIDI.Port Jack.Output
  67              -> ReactiveFieldReadWrite IO [(Frames, RawMessage)]
  68              -> ReactiveFieldRead IO (LTempo, Int, [(Frames, RawMessage)])
  69              -> Jack.NFrames
  70              -> Sync.ExceptionalT E.Errno IO ()
  71 jackCallBack client input output toProcessRV boardInRV
  72   nframes@(Jack.NFrames nframesInt') = do
  73   let inMIDIRV = inMIDIEvent input nframes
  74       outMIDIRV = outMIDIEvent output nframes
  75       nframesInt = fromIntegral nframesInt' :: Int
  76   -- This gets the sample rate of the client and the last frame number
  77   -- it processed. We then use it to calculate the current absolute time
  78   sr <- Trans.lift $ Jack.getSampleRate client
  79   (Jack.NFrames lframeInt) <- Trans.lift $ Jack.lastFrameTime client
  80   -- We write the content of the input buffer to the input of a
  81   -- translation signal function.
  82   -- /!\ Should be moved elsewhere
  83   (inRaw, outPure) <- Trans.lift $ yampaReactiveDual [] readMessages
  84   Trans.lift (inMIDIRV =:> inRaw)
  85   (tempo, chan, boardIn') <- Trans.lift $ reactiveValueRead boardInRV
  86   let boardIn = ([],[],boardIn')
  87   outMIDI <- Trans.lift $ reactiveValueRead outPure
  88   -- We translate all signals to be sent into low level signals and
  89   -- write them to the output buffer.
  90   (inPure, outRaw) <- Trans.lift $ yampaReactiveDual
  91                       (defaultTempo, sr, chan, ([],[],[])) gatherMessages
  92   -- This should all go in its own IO action
  93   Trans.lift $ reactiveValueWrite inPure
  94                (tempo, sr, chan, (boardIn `mappend` outMIDI))
  95   Trans.lift (reactiveValueRead outRaw <**>
  96               (mappend <$> reactiveValueRead toProcessRV) >>=
  97               reactiveValueWrite toProcessRV)
  98   Trans.lift $ do
  99     (go, old') <- schedule nframesInt <$> reactiveValueRead toProcessRV
 100     let old = map (BF.first (+ (- nframesInt))) old'
 101     reactiveValueWrite outMIDIRV go
 102     reactiveValueWrite toProcessRV old
 103   --------------
 104   return ()