ticker.h

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/*
 * Copyright (C) 2008-2009 Hans Baier <hansfbaier@googlemail.com>
 * Copyright (C) 2009-2010 David Robillard <d@drobilla.net>
 * Copyright (C) 2009-2017 Paul Davis <paul@linuxaudiosystems.com>
 * Copyright (C) 2010 Carl Hetherington <carl@carlh.net>
 * Copyright (C) 2013 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
#include "pbd/signals.h"
 
#include "ardour/libardour_visibility.h"
#include "ardour/session_handle.h"
#include "ardour/types.h"
 
#pragma once
 
namespace ARDOUR
{
class Session;
class MidiPort;
 
class LIBARDOUR_API MidiClockTicker
{
public:
        MidiClockTicker (Session&);
        MidiClockTicker (const MidiClockTicker&) = delete;
        MidiClockTicker& operator= (const MidiClockTicker&) = delete;
        virtual ~MidiClockTicker ();
 
        void tick (samplepos_t, samplepos_t, pframes_t, samplecnt_t);
 
private:
        ARDOUR::Session&      _session;
        std::shared_ptr<MidiPort> _midi_port;
        bool                  _rolling;
        double                _next_tick;
        uint32_t              _beat_pos;
        uint32_t              _clock_cnt;
        samplepos_t           _transport_pos;
        LatencyRange          _mclk_out_latency;
        PBD::ScopedConnection _latency_connection;
 
        void   reset ();
        void   resync_latency (bool);
        double one_ppqn_in_samples (samplepos_t transport_position) const;
 
        void send_midi_clock_event (pframes_t offset, pframes_t nframes);
        void send_start_event (pframes_t offset, pframes_t nframes);
        void send_continue_event (pframes_t offset, pframes_t nframes);
        void send_stop_event (pframes_t offset, pframes_t nframes);
        void send_position_event (uint32_t midi_clocks, pframes_t offset, pframes_t nframes);
};
 
} // namespace ARDOUR