Method rotateBufferThread

core/audio/AudioPlayer.cpp:452–590

rotateBufferThread is used to rotate alBufferData for _alSource when playing big audio file

// rotateBufferThread is used to rotate alBufferData for _alSource when playing big audio file
void AudioPlayer::rotateBufferThread(int offsetFrame)
{
    yasio::set_thread_name("axmol-audio");

    char* tmpBuffer           = nullptr;
    auto& fullPath            = _audioCache->_fileFullPath;
    AudioDecoder* decoder     = AudioDecoderManager::createDecoder(fullPath);
    long long rotateSleepTime = static_cast<long long>(QUEUEBUFFER_TIME_STEP * 1000) / 2;
    do
    {
        BREAK_IF(decoder == nullptr || !decoder->open(fullPath));

        uint32_t framesRead         = 0;
        const uint32_t framesToRead = _audioCache->_queBufferFrames;
        const uint32_t bufferSize   = decoder->framesToBytes(framesToRead);
#if AX_USE_ALSOFT
        const auto sourceFormat = decoder->getSourceFormat();
#endif
        tmpBuffer = (char*)malloc(bufferSize);
        memset(tmpBuffer, 0, bufferSize);

        if (offsetFrame != 0)
        {
            decoder->seek(offsetFrame);
        }

        ALint sourceState;
        ALint bufferProcessed = 0;
        bool needToExitThread = false;

        while (!_stopping)
        {
            alGetSourcei(_alSource, AL_SOURCE_STATE, &sourceState);
            if (sourceState == AL_PLAYING)
            {
                alGetSourcei(_alSource, AL_BUFFERS_PROCESSED, &bufferProcessed);
                while (bufferProcessed > 0)
                {
                    bufferProcessed--;
                    if (_timeDirty)
                    {
                        _timeDirty  = false;
                        offsetFrame = _currTime * decoder->getSampleRate() * decoder->getChannelCount();
                        decoder->seek(offsetFrame);
                    }
                    else
                    {
                        _currTime += QUEUEBUFFER_TIME_STEP;
                        if (_currTime > _audioCache->_duration)
                        {
                            if (_loop)
                            {
                                _currTime = 0.0f;
                            }
                            else
                            {
                                _currTime = _audioCache->_duration;
                            }