view data/midi/MIDIInput.cpp @ 1879:652c5360e682

Ensure transforms are populated before instantiateDefaultPluginFor runs - otherwise if we have prior knowledge of a transform id, we can find ourselves trying to instantiate it before the plugin factory has heard of it and e.g. knows which server to use
author Chris Cannam
date Thu, 25 Jun 2020 12:20:06 +0100
parents 157c62ff0056
children
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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006-2009 Chris Cannam and QMUL.
    
    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.  See the file
    COPYING included with this distribution for more information.
*/

#include "MIDIInput.h"

#include "rtmidi/RtMidi.h"

#include "system/System.h"

MIDIInput::MIDIInput(QString name, FrameTimer *timer) :
    m_rtmidi(nullptr),
    m_frameTimer(timer),
    m_buffer(1023)
{
    try {
        std::vector<RtMidi::Api> apis;
        RtMidi::getCompiledApi(apis);
        RtMidi::Api preferredApi = RtMidi::UNSPECIFIED;
        for (auto a: apis) {
            if (a == RtMidi::UNSPECIFIED || a == RtMidi::RTMIDI_DUMMY) {
                continue;
            }
            preferredApi = a;
            break;
        }
        if (preferredApi == RtMidi::UNSPECIFIED) {
            SVCERR << "ERROR: MIDIInput: No RtMidi APIs compiled in" << endl;
        } else {

            m_rtmidi = new RtMidiIn(preferredApi, name.toStdString());

            int n = m_rtmidi->getPortCount();

            if (n == 0) {

                SVDEBUG << "NOTE: MIDIInput: No input ports available" << endl;
                delete m_rtmidi;
                m_rtmidi = nullptr;

            } else {

                m_rtmidi->setCallback(staticCallback, this);

                SVDEBUG << "MIDIInput: Available ports are:" << endl;
                for (int i = 0; i < n; ++i) {
                    SVDEBUG << i << ". " << m_rtmidi->getPortName(i) << endl;
                }
                SVDEBUG << "MIDIInput: Using first port (\""
                        << m_rtmidi->getPortName(0) << "\")" << endl;
            
                m_rtmidi->openPort(0, tr("Input").toStdString());
            }
        }
        
    } catch (const RtMidiError &e) {
        SVCERR << "ERROR: RtMidi error: " << e.getMessage() << endl;
        delete m_rtmidi;
        m_rtmidi = nullptr;
    }
}

MIDIInput::~MIDIInput()
{
    delete m_rtmidi;
}

void
MIDIInput::staticCallback(double timestamp, std::vector<unsigned char> *message,
                          void *userData)
{
    ((MIDIInput *)userData)->callback(timestamp, message);
}

void
MIDIInput::callback(double timestamp, std::vector<unsigned char> *message)
{
    SVDEBUG << "MIDIInput::callback(" << timestamp << ")" << endl;
    // In my experience so far, the timings passed to this function
    // are not reliable enough to use.  We request instead an audio
    // frame time from whatever FrameTimer we have been given, and use
    // that as the event time.
    if (!message || message->empty()) return;
    unsigned long t = m_frameTimer->getFrame();
    MIDIByte code = (*message)[0];
    MIDIEvent ev(t,
                 code,
                 message->size() > 1 ? (*message)[1] : 0,
                 message->size() > 2 ? (*message)[2] : 0);
    postEvent(ev);
}

MIDIEvent
MIDIInput::readEvent()
{
    MIDIEvent *event = m_buffer.readOne();
    MIDIEvent revent = *event;
    delete event;
    return revent;
}

void
MIDIInput::postEvent(MIDIEvent e)
{
    int count = 0, max = 5;
    while (m_buffer.getWriteSpace() == 0) {
        if (count == max) {
            SVCERR << "ERROR: MIDIInput::postEvent: MIDI event queue is full and not clearing -- abandoning incoming event" << endl;
            return;
        }
        SVCERR << "WARNING: MIDIInput::postEvent: MIDI event queue (capacity " << m_buffer.getSize() << ") is full!" << endl;
        SVDEBUG << "Waiting for something to be processed" << endl;
#ifdef _WIN32
        Sleep(1);
#else
        sleep(1);
#endif
        count++;
    }

    MIDIEvent *me = new MIDIEvent(e);
    m_buffer.write(&me, 1);
    emit eventsAvailable();
}