scales.hs

-- eval the functions below first, then you can do this:

midiInstrument $ (|+| note "45") $ mel m9 5 "0*8"

-- above, plays the first 5 notes of a m9 arpeggio, over a pattern of eighth notes, 
-- starting at MIDI note #45

-- the "mel" function below relies on a "scramble" function which I don't 
-- really like. I'm not good enough at haskell to know to how pick
-- random values out of the scale/arpeggio.

let remPos num den = if x<0 then x+den else x where x = rem num den
    scaleElt scale n = fromIntegral . (scale !!) $ fromIntegral $ remPos n (fromIntegral $ length scale)
    scaleOctave scale n = (12 *) . fromIntegral . floor . ((fromIntegral n) /) $ fromIntegral $ length scale
    sc s n = scaleOctave s n + scaleElt s n
    ionian = [0,2,4,5,7,9,11]
    aeolian = [0,2,3,5,7,8,10]
    locrian = [0,1,3,5,6,8,10]
    phryg = [0,1,3,5,7,8,10]
    lydian = [0,2,4,6,7,9,11]
    enig = [0,1,3,5,6,8,10,11]
    minor = [0,3,7]
    major = [0,4,7]
    _9 = [0,4,7,10,14]
    ninesus4 = [0,5,7,10,14]
    add9 = [0,4,7,14]
    madd9 = [0,3,7,14]
    maj9 = [0,4,7,11,14]
    m9 = [0,3,7,10,14]
    sus2 = [0,2,7]
    sus4 = [0,5,7]
    _7 = [0,4,7,10]
    m7 = [0,3,7,10]
    eleven = [0,4,7,10,14,17]
    _11 = [0,4,7,10,14,17]
    m11 = [0,3,7,10,14,17]
    _13 = [0,4,7,10,14,21]
    m13 = [0,3,7,10,14,21]
    mpent = [0, 3, 5, 7, 10, 12]
    pent = [0, 2, 4, 7, 9, 12]
    runUpOneOctave = run $ length ionian
    runUpTwoOctaves = run $ 2 * length ionian
    runUpThreeOctaves = run $ 3 * length ionian
    runUpAndDown = append runUpTwoOctaves $ (+1) <$> rev runUpTwoOctaves
    scramble p = within (0.25, 0.5) (0.25 <~) $ within (0.5,1) (1.25 ~>) $ within (0, 0.5) (0.5 ~>) $ within (0.25, 0.75) (0.75 <~) $ p
    mel' scale runSize f cycles p = note (preplace(1,cycles) p (f $ sc scale <$> run runSize))
    melOld scale runSize p = note (preplace(1,1) p (sc scale <$> run runSize))
    mel scale runSize p = mel' scale runSize (scramble) 4 p
    arpup scale x = note (sc scale <$> run x)
    arpdown scale x = note (rev $ sc scale <$> run x)