-- phase modulation with slow beats (jmcc) #6

import Sound.SC3 {- hsc3 -}
import Sound.SC3.Lang.Control.OverlapTexture {- hsc3-lang -}

rand2 :: ID a => a -> UGen -> UGen
rand2 e n = rand e (-n) n

nrec :: (Num a, Ord a) => a -> (t -> t) -> t -> t
nrec n f st = if n > 0 then nrec (n - 1) f (f st) else st

pmwsb :: UGen
pmwsb =
    let x = mouseX KR 100 6000 Exponential 0.2 -- random freq of new events
        y = mouseY KR 0 2 Linear 0.2 -- modulation index
        o (e,a) = let f = rand e 0 x
                  in (succ e,fSinOsc AR (mce [f,f + rand2 'α' 1]) 0 * y + a)
        (_,ph) = nrec 3 o ('β',0)
        freq = rand 'γ' 0 x
    in sinOsc AR (mce [freq, freq + rand2 'δ' 1]) ph * 0.1

main :: IO ()
main = overlapTextureU (4,4,4,maxBound) pmwsb