LV2 Toolkit  1.2.0
beep.cpp
/*
beep.cpp - LV2 Toolkit API Demonstration Plugin
Copyright (C) 2004-2010 Lars Luthman
Updated for LVTK by Michael Fisher <mfisher31@gmail.com>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <lvtk/synth.hpp>
#include "beep.h"
class BeepVoice : public lvtk::Voice
{
public:
BeepVoice (double rate)
: m_key(lvtk::INVALID_KEY), m_rate(rate), m_period(10), m_counter(0)
{ }
void
on (unsigned char key, unsigned char velocity)
{
m_key = key;
m_period = m_rate * 4.0 / lvtk::key2hz(m_key);
}
void
off (unsigned char velocity)
{
m_key = lvtk::INVALID_KEY;
}
unsigned char
get_key() const
{
return m_key;
}
void
render(uint32_t from, uint32_t to)
{
if (m_key == lvtk::INVALID_KEY) return;
for (uint32_t i = from; i < to; ++i)
{
float s = -0.25 + 0.5 * (m_counter > m_period / 2);
m_counter = (m_counter + 1) % m_period;
p(p_left)[i] += s;
p(p_right)[i] += s;
}
}
protected:
unsigned char m_key;
double m_rate;
uint32_t m_period;
uint32_t m_counter;
};
class Beep : public lvtk::Synth<BeepVoice, Beep>
{
public:
Beep (double rate) : lvtk::Synth<BeepVoice, Beep> (p_n_ports, p_midi)
{
add_voices (new BeepVoice(rate), new BeepVoice(rate), new BeepVoice(rate));
add_audio_outputs (p_left, p_right);
}
};
static int _ = Beep::register_class(p_uri);