gistfile1.txt

#!/usr/bin/perl
use strict;
use warnings;

BEGIN {
	unshift @INC, '../lib';
}

use Sound::NeSynth;

my $kick = {
	osc => {
		freq => 55,
		waveform => 'sin',
		mod => { speed => 0.02, depth => 0.2, waveform => 'noise', curve => 1.4 }
	},
	amp => { sec => 0.28, waveform => 'env', curve => 4.5 }
};

my $snr1 = {
	osc => {
		freq => 1400,
		waveform => 'tri',
		mod => { speed => 1.12, depth => 1.0, waveform => 'noise' },
	},
	amp => { sec => 0.2, waveform => 'env', curve => 8.2 }
};

my $perc = {
	osc => {
		freq => 660,
		waveform => 'pulse',
		mod => { speed => 0.2, depth => 0.07, waveform => 'saw' },
	},
	amp => { sec => 0.26, waveform => 'env', curve => 3.2 }
};

my $c_hat = {
	osc => {
		freq => 9000,
		waveform => 'noise',
		mod => { speed => 1.03, depth =>  4.0, waveform => 'noise' }
	},
	amp => { sec => 0.09, waveform => 'env', curve => 8.0 }
};

my %patterns = (
	kick   => [ 0,0,1,1,0,0,0,0, 1,0,0,0,0,1,0,0,  0,0,1,0,0,1,0,0, 0,0,1,1,0,0,0,0,  0,0,1,0,0,0,0,1, 0,0,1,1,0,0,0,0,  0,0,1,0,0,0,0,0, 1,0,0,1,0,0,1,0 ],
	snr1   => [ 0,0,0,0,1,0,0,0, 0,0,0,0,1,0,0,0,  0,0,0,0,1,0,0,0, 0,0,0,0,1,0,0,0,  0,0,0,0,1,0,0,0, 0,0,0,0,1,0,0,0,  0,0,0,1,0,0,0,0, 0,0,0,0,1,0,0,0 ],
	perc   => [ 0,0,0,1,0,0,0,0, 0,0,1,0,0,1,0,0,  0,0,0,1,0,0,0,0, 0,0,1,0,0,1,0,0,  0,0,0,1,0,0,0,0, 0,0,1,0,0,1,0,0,  0,0,0,1,0,0,0,0, 0,0,1,0,0,1,0,0, ],
	c_hat1 => [ 1,0,1,1,1,1,0,1, 1,0,1,1,1,1,0,0,  0,0,1,1,1,1,1,1, 1,1,1,1,1,1,0,0,  1,0,1,1,1,1,0,1, 1,0,1,1,1,1,1,0,  1,0,1,1,1,1,1,1, 1,0,1,1,1,1,1,0 ],
);

my $bpm = 88;
my $synth = Sound::NeSynth->new();
$synth->render({
	bpm => $bpm, # beats per minute
	beats => [
		{ seq => $patterns{kick},   tone => $kick,  vol => 0.98 },
		{ seq => $patterns{snr1},   tone => $snr1,  vol => 0.45 },
		{ seq => $patterns{perc},   tone => $perc,  vol => 0.03 },
		{ seq => $patterns{c_hat1}, tone => $c_hat, vol => 0.08 },
	],
	swing => 0.33,
});


use Audio::PortAudio;

my ( $sample_rate, $frames_per_buffer, $stream_flags ) = ( 44100, 512, undef );
my $api = Audio::PortAudio::default_host_api();
printf STDERR "Going to play via %s\nCtrl+c to stop...", $api->name;
my $device = $api->default_output_device;
my $stream = $device->open_write_stream( {
     channel_count => 2,
     sample_format => 'float32'
  },
  $sample_rate,
  $frames_per_buffer,
  $stream_flags,
);

my $length = (44100 * 60 / $bpm) * 16;
my $idx = 0;

my $delay_buffer = [];
my $delay_len = 44100 * 60 / $bpm * 0.492;
my $delay_idx = 0;
my $delay_feedback = 0.18;

# Infinite loop...
while (1) {
    my @buffer_ary;
    my @right;
    my $i = 0;
    my $wa = $stream->write_available;
    for ( 0..$wa - 1 ) {
        my $v = $synth->{samples_ref}[$idx] || 0.0;
        $v += ( $delay_buffer->[$delay_idx] || 0.0 ) * $delay_feedback;
        $delay_buffer->[$delay_idx] = $v;
        $delay_idx = ($delay_idx + 1) % $delay_len;
        # write both left and right channel
        $buffer_ary[$i++] = $v;
        $buffer_ary[$i++] = $v;
        $idx = ( $idx + 1 ) % $length;
    }
    my $buffer = pack("f*", @buffer_ary);
    $stream->write($buffer);
}

__END__