public int CalculateSamplesNeeded()
{
long currentWriteTime = Stopwatch.GetTimestamp();
bool isInitializing = _lastWriteTime == 0;
bool detectedUnderrun = false;
if (!isInitializing)
{
double elapsedSeconds = (currentWriteTime - _lastWriteTime) / (double)Stopwatch.Frequency;
// Due to rounding errors this doesn't work well in audio throttle mode unless enough time has passed
if (elapsedSeconds >= 0.001)
{
_remainingSamples -= (int)Math.Round(elapsedSeconds * _sound.SampleRate);
if (_remainingSamples < 0)
{
_remainingSamples = 0;
detectedUnderrun = true;
}
_lastWriteTime = currentWriteTime;
}
}
else
{
_lastWriteTime = currentWriteTime;
}
int samplesNeeded = BufferSizeSamples - _remainingSamples;
if (isInitializing || detectedUnderrun)
{
_sound.HandleInitializationOrUnderrun(detectedUnderrun, ref samplesNeeded);
}
return(samplesNeeded);
}
public int CalculateSamplesNeeded()
{
int samplesNeeded = 0;
if (IsPlaying)
{
try
{
long currentWriteTime = Stopwatch.GetTimestamp();
int playCursor = _deviceBuffer.CurrentPlayPosition;
int writeCursor = _deviceBuffer.CurrentWritePosition;
bool isInitializing = _actualWriteOffsetBytes == -1;
bool detectedUnderrun = false;
if (!isInitializing)
{
double elapsedSeconds = (currentWriteTime - _lastWriteTime) / (double)Stopwatch.Frequency;
double bufferSizeSeconds = (double)BufferSizeSamples / _sound.SampleRate;
int cursorDelta = CircularDistance(_lastWriteCursor, writeCursor, BufferSizeBytes);
cursorDelta += BufferSizeBytes * (int)Math.Round((elapsedSeconds - (cursorDelta / (double)(_sound.SampleRate * _sound.BlockAlign))) / bufferSizeSeconds);
_filledBufferSizeBytes -= cursorDelta;
detectedUnderrun = _filledBufferSizeBytes < 0;
}
if (isInitializing || detectedUnderrun)
{
_actualWriteOffsetBytes = writeCursor;
_filledBufferSizeBytes = 0;
}
samplesNeeded = CircularDistance(_actualWriteOffsetBytes, playCursor, BufferSizeBytes) / _sound.BlockAlign;
if (isInitializing || detectedUnderrun)
{
_sound.HandleInitializationOrUnderrun(detectedUnderrun, ref samplesNeeded);
}
_lastWriteTime = currentWriteTime;
_lastWriteCursor = writeCursor;
}
catch (DirectSoundException)
{
samplesNeeded = 0;
}
}
return(samplesNeeded);
}
