-- http://www.create.ucsb.edu/pipermail/sc-users/2007-August/035957.html

import Sound.SC3.ID {- hsc3 -}

steam :: UGen -> UGen -> UGen -> UGen
steam time n1 n2 =
    let piston = lfSaw AR (xLine AR 1 7 time DoNothing) 0
        air = lpf (n1 * piston + n2 * piston) 5000
        e = envGen AR 1 1 0 1 DoNothing (envSine time 9)
    in bpf air 600 (1 + e)

whistle :: UGen -> UGen -> UGen
whistle time n3 =
    let f = [800,600,1200,990]
        s = klankSpec f [1,1,1,1] [1,1,1,1]
        t = [0,0,1,1,0,0,1,1,0,0,1,0]
        l = [2,0,0.2,0,0.2,0,0.8,0,4,0,3]
        d = Envelope t l (repeat EnvLin) Nothing Nothing
        e = envGen AR 1 1 0 (time/10) DoNothing d
    in klank (n3 * 0.004) 1 0 1 s * e

train :: UGen
train =
    let time = 24
        loc = let e = Envelope [-0.8,0.8] [time + 2] [EnvSin,EnvSin] Nothing Nothing
              in envGen AR 1 1 0 1 RemoveSynth e
        n1 = whiteNoise 'α' AR
        n2 = pinkNoise 'β' AR
        n3 = whiteNoise 'γ' AR
    in pan2 (steam time n1 n2 + whistle time n3) loc 1

main :: IO ()
main =  audition (out 0 train)