Function audio_write

lib/sequence/sequence.cpp:509–562

FIXME: perhaps we should use wz's routine for audio? loads up the audio buffers, and calculates audio sync time.

// FIXME: perhaps we should use wz's routine for audio?
// loads up the audio buffers, and calculates audio sync time.
static void audio_write(void)
{
	ALint processed = 0;
	ALint queued = 0;

	alGetSourcei(audiodata.source, AL_BUFFERS_PROCESSED, &processed);
	alGetSourcei(audiodata.source, AL_BUFFERS_QUEUED, &queued);
	if ((audiodata.totbufstarted < 2 || processed) && audiodata.audiobuf_fill > 0)
	{
		// we have audiobuf_fill bytes of data
		ALuint oldbuffer = 0;

		if (audiodata.totbufstarted == 0)
		{
			oldbuffer = audiodata.buffer1;
		}
		else if (audiodata.totbufstarted == 1)
		{
			oldbuffer = audiodata.buffer2;
		}
		else
		{
			ALint buffer_size = 0;
			ogg_int64_t current_sample = 0;

			alSourceUnqueueBuffers(audiodata.source, 1, &oldbuffer);
			alGetBufferi(oldbuffer, AL_SIZE, &buffer_size);
			// audio time sync
			audioTime += (double) buffer_size / (videodata.vi.rate * videodata.vi.channels);
			debug(LOG_VIDEO, "Audio sync");
			current_sample = audiobuf_granulepos - audiodata.audiobuf_fill / 2 / videodata.vi.channels;
			sampletimeOffset -= getTimeNow() - 1000 * current_sample / videodata.vi.rate;
		}

		alBufferData(oldbuffer, (videodata.vi.channels == 1 ? AL_FORMAT_MONO16 : AL_FORMAT_STEREO16),
		             audiobuf, audiodata.audiobuf_fill, static_cast<ALsizei>(videodata.vi.rate));

		alSourceQueueBuffers(audiodata.source, 1, &oldbuffer);
		audiodata.totbufstarted++;
		if (audiodata.totbufstarted > 2)
		{
			audiodata.totbufstarted = 2;
		}

		if (sourcestate != AL_PLAYING)
		{
			debug(LOG_VIDEO, "starting source\n");
			alSourcePlay(audiodata.source);
		}

		audiobuf_ready = false;
		audiodata.audiobuf_fill = 0;
	}
}

static void seq_InitOgg(void)
{