RCMA/Layer/Layer.hs

   1 {-# LANGUAGE Arrows #-}
   2
   3 module Reactogon.Layer.Layer where
   4
   5 import Reactogon.Semantics
   6 import Reactogon.Layer.Board
   7 import Reactogon.Global.Clock
   8 import FRP.Yampa
   9
  10 -- Data representing the state of a layer. It is updated continuously.
  11 data Layer = Layer { relTempo    :: Double
  12                    , relPitch    :: RelPitch
  13                    , strength    :: Strength
  14                    , beatsPerBar :: BeatsPerBar
  15                    , beatCounter :: BeatNo
  16                    }
  17
  18 layerTempo :: SF (Tempo, Layer) Tempo
  19 layerTempo = proc (t, Layer { relTempo = r }) -> do
  20   returnA -< floor $ r * fromIntegral t
  21
  22 -- The layer is modified after the beat as been
  23 layerMetronome :: SF (Tempo, Layer) (Event (BeatNo, Layer))
  24 layerMetronome = proc (t, l@Layer { beatCounter = b , beatsPerBar = bpb}) -> do
  25   eb <- metronome <<< layerTempo -< (t, l)
  26   returnA -< eb `tag` let nb = nextBeatNo b bpb in (nb, l { beatCounter = nb })
  27
  28 -- A layer is a producer of events triggered by the system beat clock.
  29 layer :: SF () (Event Beat) ->  SF Layer (Event Note)
  30 layer beatSource = undefined