livetrax/libs/ardour/midi_port.cc

/*
    Copyright (C) 2006 Paul 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.
*/

#include <cassert>
#include <iostream>

#include "ardour/midi_port.h"
#include "ardour/data_type.h"
#include "ardour/audioengine.h"

using namespace ARDOUR;
using namespace std;

MidiPort::MidiPort (const std::string& name, Flags flags)
	: Port (name, DataType::MIDI, flags)
	, _has_been_mixed_down (false)
	, _resolve_required (false)
	, _input_active (true)
{
	_buffer = new MidiBuffer (AudioEngine::instance()->raw_buffer_size (DataType::MIDI));
}

MidiPort::~MidiPort()
{
	delete _buffer;
}

void
MidiPort::cycle_start (pframes_t nframes)
{
	Port::cycle_start (nframes);

	_buffer->clear ();

	assert (_buffer->size () == 0);

	if (sends_output ()) {
		jack_midi_clear_buffer (jack_port_get_buffer (_jack_port, nframes));
	}
}

MidiBuffer &
MidiPort::get_midi_buffer (pframes_t nframes)
{
	if (_has_been_mixed_down) {
		return *_buffer;
	}

	if (receives_input ()) {

		if (_input_active) {

			void* jack_buffer = jack_port_get_buffer (_jack_port, nframes);
			const pframes_t event_count = jack_midi_get_event_count (jack_buffer);
			
			assert (event_count < _buffer->capacity());
			
			/* suck all relevant MIDI events from the JACK MIDI port buffer
			   into our MidiBuffer
			*/
			
			for (pframes_t i = 0; i < event_count; ++i) {
				
				jack_midi_event_t ev;
				
				jack_midi_event_get (&ev, jack_buffer, i);
				
				if (ev.buffer[0] == 0xfe) {
					/* throw away active sensing */
					continue;
				}
				
				/* check that the event is in the acceptable time range */
				
				if ((ev.time >= (_global_port_buffer_offset + _port_buffer_offset)) &&
				    (ev.time < (_global_port_buffer_offset + _port_buffer_offset + nframes))) {
					_buffer->push_back (ev);
				} else {
					cerr << "Dropping incoming MIDI at time " << ev.time << "; offset="
					     << _global_port_buffer_offset << " limit="
					     << (_global_port_buffer_offset + _port_buffer_offset + nframes) << "\n";
				}
			} 

		} else {
			_buffer->silence (nframes);
		}

	} else {
		_buffer->silence (nframes);
	}

	if (nframes) {
		_has_been_mixed_down = true;
	}

	return *_buffer;
}


void
MidiPort::cycle_end (pframes_t /*nframes*/)
{
	_has_been_mixed_down = false;
}

void
MidiPort::cycle_split ()
{
	_has_been_mixed_down = false;
}

void
MidiPort::resolve_notes (void* jack_buffer, MidiBuffer::TimeType when)
{
	for (uint8_t channel = 0; channel <= 0xF; channel++) {

		uint8_t ev[3] = { ((uint8_t) (MIDI_CMD_CONTROL | channel)), MIDI_CTL_SUSTAIN, 0 };

		/* we need to send all notes off AND turn the
		 * sustain/damper pedal off to handle synths
		 * that prioritize sustain over AllNotesOff
		 */

		if (jack_midi_event_write (jack_buffer, when, ev, 3) != 0) {
			cerr << "failed to deliver sustain-zero on channel " << channel << " on port " << name() << endl;
		}

		ev[1] = MIDI_CTL_ALL_NOTES_OFF;

		if (jack_midi_event_write (jack_buffer, 0, ev, 3) != 0) {
			cerr << "failed to deliver ALL NOTES OFF on channel " << channel << " on port " << name() << endl;
		}
	}
}

void
MidiPort::flush_buffers (pframes_t nframes)
{
	if (sends_output ()) {

		void* jack_buffer = jack_port_get_buffer (_jack_port, nframes);

		if (_resolve_required) {
			/* resolve all notes at the start of the buffer */
			resolve_notes (jack_buffer, 0);
			_resolve_required = false;
		}

		for (MidiBuffer::iterator i = _buffer->begin(); i != _buffer->end(); ++i) {

			const Evoral::MIDIEvent<MidiBuffer::TimeType> ev (*i, false);

			// event times are in frames, relative to cycle start

			assert (ev.time() < (nframes + _global_port_buffer_offset + _port_buffer_offset));

			if (ev.event_type() == LoopEventType) {
				resolve_notes (jack_buffer, ev.time());
				continue;
			}

			if (ev.time() >= _global_port_buffer_offset + _port_buffer_offset) {
				if (jack_midi_event_write (jack_buffer, (jack_nframes_t) ev.time(), ev.buffer(), ev.size()) != 0) {
					cerr << "write failed, drop flushed note off on the floor, time "
					     << ev.time() << " > " << _global_port_buffer_offset + _port_buffer_offset << endl;
				}
			} else {
				cerr << "drop flushed event on the floor, time " << ev
				     << " to early for " << _global_port_buffer_offset + _port_buffer_offset << endl;
			}
		}
	}
}

void
MidiPort::transport_stopped ()
{
	_resolve_required = true;
}

void
MidiPort::realtime_locate ()
{
	_resolve_required = true;
}

void
MidiPort::reset ()
{
	Port::reset ();
	delete _buffer;
	_buffer = new MidiBuffer (AudioEngine::instance()->raw_buffer_size (DataType::MIDI));
}

void
MidiPort::set_input_active (bool yn)
{
	_input_active = yn;
}