Chasm of the Apocalypse

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SndBuf  buff => FFT fft =^ IFFT ifft => blackhole;
Impulse imp => LPF lpf => blackhole;
dac => WvOut w => blackhole;
lpf => PitShift ps1 => dac;
lpf => PitShift ps2 => dac;
lpf => PitShift ps3 => dac;

1000 => lpf.freq;
0.25 => ps1.shift;
0.5 => ps1.gain;
2 => ps2.shift;
0.8 => ps2.gain;
0.125 => ps3.shift;
0.5 => ps3.gain;

30.0 => float stretch;
5::second => dur window_dur;

me.sourceDir() + "/cc.wav" => string filename;
buff.read(filename);
buff.samples() / (buff.length() / 1::second) => float sample_rate;

me.sourceDir() + "/output_cc.wav" => w.wavFilename;

((window_dur / 1::second) * sample_rate) $ int => int window_size;
(window_size / 2) $ int => int half_window_size;

window_size => fft.size;
Windowing.hann(window_size) => fft.window;
Windowing.hann(window_size) => ifft.window;

complex s[half_window_size];
float ifft_s[window_size];
float old_ifft_s[half_window_size];

(1+Math.sqrt(0.5))*0.5 => float hinv_sqrt2;
float hinv_buf[half_window_size];
for(int i; i  hinv_buf[i];
}

0 => int start_pos;
(half_window_size / stretch) $ int => int displace_pos;

// control loop
while( start_pos  buff.pos;

    fft.upchuck();
    fft.spectrum(s);
    polar pol;
    for(int i; i pol;
        Math.random2f(0, 2 * pi) => pol.phase;
        pol $ complex => s[i];
    }
    ifft.transform(s);
    ifft.samples(ifft_s);

    float output;
    for(int i; i  output;
        ifft_s[i+half_window_size] => old_ifft_s[i];
        if(output > 1.0) {
            1.0 => output;
        } else if(output  output;
        }
        output => imp.next;
        1::samp => now;
    }

    displace_pos +=> start_pos;
}