ardour/libs/midi++2/channel.cc

/*
    Copyright (C) 1998-99 Paul Barton-Davis 

    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.

    $Id$
*/

#include <cstring>
#include "midi++/types.h"
#include "midi++/port.h"
#include "midi++/channel.h"

using namespace MIDI;

Channel::Channel (byte channelnum, PortBase &p) 
	: _port (p)
{
	_channel_number = channelnum;

	reset (0, 1, false);
}	

void
Channel::connect_signals ()
{
	_port.parser()->channel_pressure[_channel_number].connect_same_thread (*this, boost::bind (&Channel::process_chanpress, this, _1, _2));
	_port.parser()->channel_note_on[_channel_number].connect_same_thread (*this, boost::bind (&Channel::process_note_on, this, _1, _2));
	_port.parser()->channel_note_off[_channel_number].connect_same_thread (*this, boost::bind (&Channel::process_note_off, this, _1, _2));
	_port.parser()->channel_poly_pressure[_channel_number].connect_same_thread (*this, boost::bind (&Channel::process_polypress, this, _1, _2));
	_port.parser()->channel_program_change[_channel_number].connect_same_thread (*this, boost::bind (&Channel::process_program_change, this, _1, _2));
	_port.parser()->channel_controller[_channel_number].connect_same_thread (*this, boost::bind (&Channel::process_controller, this, _1, _2));
	_port.parser()->channel_pitchbend[_channel_number].connect_same_thread (*this, boost::bind (&Channel::process_pitchbend, this, _1, _2));

	_port.parser()->reset.connect_same_thread (*this, boost::bind (&Channel::process_reset, this, _1));
}

void
Channel::reset (timestamp_t timestamp, framecnt_t /*nframes*/, bool notes_off)
{
	_program_number = _channel_number;
	_bank_number = 0;
	_pitch_bend = 0;

	_last_note_on = 0;
	_last_note_off = 0;
	_last_on_velocity = 0;
	_last_off_velocity = 0;

	if (notes_off) {
		all_notes_off (timestamp);
	}

	memset (_polypress, 0, sizeof (_polypress));
	memset (_controller_msb, 0, sizeof (_controller_msb));
	memset (_controller_lsb, 0, sizeof (_controller_lsb));
       
	/* zero all controllers XXX not necessarily the right thing */

	memset (_controller_val, 0, sizeof (_controller_val));

	for (int n = 0; n < 128; n++) {
		_controller_14bit[n] = false;
	}

	_rpn_msb = 0;
	_rpn_lsb = 0;
	_nrpn_msb = 0;
	_nrpn_lsb = 0;

	_omni = true;
	_poly = false;
	_mono = true;
	_notes_on = 0;
}

void
Channel::process_note_off (Parser & /*parser*/, EventTwoBytes *tb) 
{
	_last_note_off = tb->note_number;
	_last_off_velocity = tb->velocity;

	if (_notes_on) {
		_notes_on--;
	}
}

void
Channel::process_note_on (Parser & /*parser*/, EventTwoBytes *tb) 
{
	_last_note_on = tb->note_number;
	_last_on_velocity = tb->velocity;
	_notes_on++;
}

void
Channel::process_controller (Parser & /*parser*/, EventTwoBytes *tb) 
{
	unsigned short cv;

	/* XXX arguably need a lock here to protect non-atomic changes
	   to controller_val[...]. or rather, need to make sure that
	   all changes *are* atomic.
	*/

	if (tb->controller_number <= 31) { /* unsigned: no test for >= 0 */

		/* if this controller is already known to use 14 bits,
		   then treat this value as the MSB, and combine it 
		   with the existing LSB.

		   otherwise, just treat it as a 7 bit value, and set
		   it directly.
		*/

		cv = (unsigned short) _controller_val[tb->controller_number];

		if (_controller_14bit[tb->controller_number]) {
			cv = ((tb->value << 7) | (cv & 0x7f));
		} else {
			cv = tb->value;
		}

		_controller_val[tb->controller_number] = (controller_value_t)cv;

	} else if ((tb->controller_number >= 32 && 
		    tb->controller_number <= 63)) {
		   
		cv = (unsigned short) _controller_val[tb->controller_number];

		/* LSB for CC 0-31 arrived. 

		   If this is the first time (i.e. its currently
		   flagged as a 7 bit controller), mark the
		   controller as 14 bit, adjust the existing value
		   to be the MSB, and OR-in the new LSB value. 

		   otherwise, OR-in the new low 7bits with the old
		   high 7.
		*/

		int cn = tb->controller_number - 32;
		   
		if (_controller_14bit[cn] == false) {
			_controller_14bit[cn] = true;
			cv = (cv << 7) | (tb->value & 0x7f);
		} else {
			cv = (cv & 0x3f80) | (tb->value & 0x7f);
		}

		_controller_val[tb->controller_number] = 
			(controller_value_t) cv;
	} else {

		/* controller can only take 7 bit values */
		
		_controller_val[tb->controller_number] = 
			(controller_value_t) tb->value;
	}

	/* bank numbers are special, in that they have their own signal
	 */

	if (tb->controller_number == 0) {
		_bank_number = (unsigned short) _controller_val[0];
		_port.parser()->bank_change (*_port.parser(), _bank_number);
		_port.parser()->channel_bank_change[_channel_number] (*_port.parser(), _bank_number);
	}

}

void
Channel::process_program_change (Parser & /*parser*/, byte val) 
{
	_program_number = val;
}

void
Channel::process_chanpress (Parser & /*parser*/, byte val) 
{
	_chanpress = val;
}

void
Channel::process_polypress (Parser & /*parser*/, EventTwoBytes *tb) 
{
	_polypress[tb->note_number] = tb->value;
}

void
Channel::process_pitchbend (Parser & /*parser*/, pitchbend_t val) 
{
	_pitch_bend = val;
}

void
Channel::process_reset (Parser & /*parser*/) 
{
	reset (0, 1);
}

/** Write a message to a channel.
 * \return true if success
 */
bool
Channel::channel_msg (byte id, byte val1, byte val2, timestamp_t timestamp)
{
	unsigned char msg[3];
	int len = 0;

	msg[0] = id | (_channel_number & 0xf);

	switch (id) {
	case off:
		msg[1] = val1 & 0x7F;
		msg[2] = val2 & 0x7F;
		len = 3;
		break;

	case on:
		msg[1] = val1 & 0x7F;
		msg[2] = val2 & 0x7F;
		len = 3;
		break;

	case MIDI::polypress:
		msg[1] = val1 & 0x7F;
		msg[2] = val2 & 0x7F;
		len = 3;
		break;

	case controller:
		msg[1] = val1 & 0x7F;
		msg[2] = val2 & 0x7F;
		len = 3;
		break;

	case MIDI::program:
		msg[1] = val1 & 0x7F;
		len = 2;
		break;

	case MIDI::chanpress:
		msg[1] = val1 & 0x7F;
		len = 2;
		break;

	case MIDI::pitchbend:
		msg[1] = val1 & 0x7F;
		msg[2] = val2 & 0x7F;
		len = 3;
		break;
	}

	return _port.midimsg (msg, len, timestamp);
}