void Empty()
{
int queued;
AL.GetSource(sourceId, ALGetSourcei.BuffersQueued, out queued);
if (queued > 0)
{
try
{
AL.SourceUnqueueBuffers(sourceId, queued);
AudioDevice.CheckALError();
}
catch (InvalidOperationException)
{
//work around OpenAL bug
int processed;
AL.GetSource(sourceId, ALGetSourcei.BuffersProcessed, out processed);
var salvaged = new int[processed];
if (processed > 0)
{
AL.SourceUnqueueBuffers(sourceId, processed, salvaged);
AudioDevice.CheckALError();
}
AL.SourceStop(sourceId);
AudioDevice.CheckALError();
Empty();
}
}
}
public void Play()
{
if (currentState == AudioPlayState.Playing)
{
return;
}
if (currentState == AudioPlayState.Stopped)
{
finished = false;
currentState = AudioPlayState.Playing;
for (int i = 0; i < bufferIds.Length; i++)
{
int length = BufferNeeded(this, buffer);
AL.BufferData(bufferIds [i], bufferFormat, buffer, length, sampleRate);
AudioDevice.CheckALError();
AL.SourceQueueBuffer(sourceId, bufferIds [i]);
AudioDevice.CheckALError();
AL.SourcePlay(sourceId);
AudioDevice.CheckALError();
}
device.Add(this);
threadRunning = true;
}
currentState = AudioPlayState.Playing;
}
internal StreamingAudio(AudioDevice device, ALFormat format, int sampleRate)
{
bufferFormat = format;
while (!device.ready)
{
;
}
var sid = AL.GenSource();
sourceId = (int)sid;
AudioDevice.CheckALError();
bufferIds = AL.GenBuffers(4);
AudioDevice.CheckALError();
this.device = device;
this.sampleRate = sampleRate;
}
internal void Update()
{
//manage state
if (currentState == AudioPlayState.Stopped)
{
AL.SourceStop(sourceId);
device.Remove(this);
threadRunning = false;
if (!userStopped)
{
if (PlaybackFinished != null)
{
PlaybackFinished(this, true);
}
}
userStopped = false;
return;
}
var state = AL.GetSourceState(sourceId);
AudioDevice.CheckALError();
if (currentState == AudioPlayState.Paused)
{
if (state != ALSourceState.Paused)
{
AL.SourcePause(sourceId);
}
return;
}
//load buffers
int processed_count;
AL.GetSource(sourceId, ALGetSourcei.BuffersProcessed, out processed_count);
while (processed_count > 0)
{
int bid = AL.SourceUnqueueBuffer(sourceId);
if (bid != 0 && !finished)
{
int length = BufferNeeded(this, buffer);
finished = length <= 0;
if (!finished)
{
AL.BufferData(bid, bufferFormat, buffer, length, sampleRate);
AL.SourceQueueBuffer(sourceId, bid);
}
}
--processed_count;
}
//check buffer
if (state == ALSourceState.Stopped && !finished)
{
AL.SourcePlay(sourceId);
}
//are we finished?
if (finished && state == ALSourceState.Stopped)
{
device.Remove(this);
currentState = AudioPlayState.Stopped;
threadRunning = false;
Empty();
if (PlaybackFinished != null)
{
PlaybackFinished(this, false);
}
}
}