Sig.hs

-- Notes on comonadic signal generation
time :: Store Double Double
time = store id 0

sineStore :: Double -> Store Double Double
sineStore freq = store sine 0
  where
    sine :: Double -> Double
    sine t = sin (2 * pi * t * freq)

sawtoothStore :: Double -> Store Double Double
sawtoothStore freq = store saw 0
    where
      saw :: Double -> Double
      saw t = ((t * freq) - fromIntegral (floor (t * freq)))

triangleStore :: Double -> Store Double Double
triangleStore = fmap asin . sineStore

squareStore :: Double -> Store Double Double
squareStore = fmap signum . sineStore

amMod :: Store (First Double) Double -> Store (First Double) Double -> Store (First Double) Double
amMod cv sig = (*) <$> cv <@> sig

window :: Double -> Double -> Store Double Double -> [Double]
window interval size store = experiment (\s -> [s, s+interval..s+size]) store

--windowAvg :: Int -> Store Int Int -> Double
--windowAvg size = (/ fromIntegral size) . fromIntegral . sum . window size