1 ! Copyright (C) 2008 Alex Chapman
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors kernel math math.constants math.functions
4 sequences sequences.modified sequences.repeating ;
7 MEMO: single-sine-wave ( samples/wave -- seq )
8 [ <iota> ] [ pi 2 * swap / [ * sin ] curry ] bi map ;
10 : (sine-wave) ( samples/wave n-samples -- seq )
11 [ single-sine-wave ] dip <cycles> ;
13 : sine-wave ( sample-freq freq seconds -- seq )
14 pick * >integer [ /i ] dip (sine-wave) ;
16 : >sine-wave-buffer ( freq seconds buffer -- buffer )
17 [ sample-freq>> -rot sine-wave ] keep swap >>data ;
19 : >silent-buffer ( seconds buffer -- buffer )
20 [ sample-freq>> * >integer 0 <repetition> ] [ data<< ] [ ] tri ;
22 TUPLE: harmonic n amplitude ;
23 C: <harmonic> harmonic
28 : harmonic-freq ( note harmonic -- freq )
31 :: note-harmonic-data ( harmonic note buffer -- data )
32 buffer sample-freq>> note harmonic harmonic-freq note secs>> sine-wave
33 harmonic amplitude>> <scaled> ;
35 : >note ( harmonics note buffer -- buffer )
36 [ [ note-harmonic-data ] 2curry map <summed> ] [ data<< ] [ ] tri ;