{-# LANGUAGE NoImplicitPrelude #-} {-# LANGUAGE MultiParamTypeClasses #-} {-# LANGUAGE FlexibleInstances #-} module Synthesizer.Plain.Wave where import qualified Synthesizer.Basic.Wave as Wave import qualified Synthesizer.Plain.ToneModulation as ToneMod import qualified Synthesizer.Plain.Interpolation as Interpolation import qualified Synthesizer.Plain.Signal as Sig import Data.Array ((!), listArray) -- import qualified Synthesizer.Basic.Phase as Phase import qualified Algebra.RealField as RealField import qualified Algebra.Ring as Ring import qualified Algebra.Additive as Additive import NumericPrelude -- import qualified Prelude as P import PreludeBase sample :: (RealField.C a) => Interpolation.T a v -> Sig.T v -> Wave.T a v sample ip wave = let len = length wave arr = listArray (0, pred len) wave in Wave.fromFunction $ \ phase -> let (n,q) = splitFraction (phase * fromIntegral len) xs = map (arr!) (map (flip mod len) (enumFrom (n - Interpolation.offset ip))) -- map (arr!) (enumFromTo (n - Interpolation.offset ip)) ++ cycle wave in Interpolation.func ip q xs {- | We assume that a tone was generated by a shape modulated oscillator. We try to reconstruct the wave function (with parameters shape control and phase) from a tone by interpolation. The unit for the shape control parameter is the sampling period. That is the shape parameter is a time parameter pointing to a momentary shape of the prototype signal. Of course this momentary shape does not exist and we can only guess it using interpolation. At the boundaries we repeat the outermost shapes that can be reconstructed entirely from interpolated data (that is, no extrapolation is needed). This way we cannot reproduce the shape at the boundaries because we have no data for cyclically extending it. On the other hand this method guarantees a nice wave shape with the required fractional period. It must be @length tone >= Interpolation.number ipStep + Interpolation.number ipLeap * ceiling period@. -} sampledTone :: (RealField.C a) => Interpolation.T a v -> Interpolation.T a v -> a -> Sig.T v -> a -> Wave.T a v sampledTone ipLeap ipStep period tone shape = Wave.Cons $ \phase -> uncurry (ToneMod.interpolateCell ipLeap ipStep) $ ToneMod.sampledToneCell (ToneMod.makePrototype (Interpolation.margin ipLeap) (Interpolation.margin ipStep) (round period) period tone) shape phase {- *Synthesizer.Basic.Wave> GNUPlot.plotFunc [] (GNUPlot.linearScale 1000 (0,12)) (\t -> sampledTone Interpolation.linear Interpolation.linear (6::Double) ([-5,-3,-1,1,3,5,-4,-4,-4,4,4,4]++replicate 20 0) t (t/6)) *Synthesizer.Plain.Oscillator> let period = 6.3::Double in GNUPlot.plotFunc [] (GNUPlot.linearScale 1000 (-10,20)) (\t -> Wave.sampledTone Interpolation.linear Interpolation.cubic period (take 20 $ staticSine 0 (1/period)) t (t/period)) -}