RCMA/Global/Clock.hs

   1 module RCMA.Global.Clock ( tempo
   2                               , metronome
   3                               , tempoToDTime
   4                               ) where
   5
   6 import RCMA.Auxiliary.Auxiliary
   7 import RCMA.Semantics
   8 import FRP.Yampa
   9
  10 import Debug.Trace
  11
  12 tempo :: Tempo -> SF () Tempo
  13 tempo = constant
  14
  15 -- The initial value is arbitrary but never appears because the switch
  16 -- is immediate.
  17 metronome :: SF Tempo (Event Beat)
  18 metronome = switch ((repeatedly (tempoToDTime 60) ())
  19                      &&&
  20                     (onChange')) (metronome')
  21   where metronome' :: Tempo -> SF Tempo (Event Beat)
  22         metronome' t = (switch ((repeatedly (tempoToDTime t) ())
  23                                  &&&
  24                                  onChange) (metronome'))
  25
  26 tempoToDTime :: Tempo -> DTime
  27 tempoToDTime = (60/) . fromIntegral