void PrepareFloatBuffers(int bufferSize)
{
var deviceBufferSize = (int)(AudioSession.CurrentHardwareSampleRate * AudioSession.CurrentHardwareIOBufferDuration + 0.5f);
Console.WriteLine("Prepare buffers: {0}, deviceBuffer: {1}, latency: {2}, {3}", bufferSize, deviceBufferSize,
AudioSession.CurrentHardwareOutputLatency, AudioSession.CurrentHardwareOutputLatency * AudioSession.CurrentHardwareSampleRate);
if (_sampleBuffer != null)
{
_sampleBuffer.Dispose();
}
var numChannels = _numInputChannels + _numOutputChannels;
if (numChannels > 0)
{
_sampleBuffer = new SampleBuffer(numChannels, bufferSize);
for (var i = 0; i < _numInputChannels; ++i)
{
_inputChannels[i] = _sampleBuffer.GetPointer(i);
}
for (var i = 0; i < _numOutputChannels; ++i)
{
_outputChannels[i] = _sampleBuffer.GetPointer(i + _numInputChannels);
}
}
}
public BufferPool(int samplesPerBlock, double sampleRate)
{
Console.WriteLine("Initializing buffer pool: samples:{0} sampleRate:{1}", samplesPerBlock, sampleRate);
Env1Buffer = new SampleBuffer(1, samplesPerBlock);
GainAmpBuffer = new SampleBuffer(new float *[3], 3, samplesPerBlock);
GainAmpBuffer.Channels[0] = Env1Buffer.GetPointer();
}
public void GetNextAudioBlock(SampleBuffer buffer, int start, int length)
{
var dest = buffer.GetPointer(0, start);
var bufferNote = _sequencer.GetBufferNote();
if (_state != State.RELEASING && (!bufferNote.IsValid || bufferNote.Start > length))
{
Memory.ZeroMem <float>(dest, length);
return;
}
var bufferPos = 0;
while (bufferPos < length)
{
if (bufferNote.IsTriggered(bufferPos))
{
LOG.Debug("Trigger");
_state = State.ATTACKING;
}
else if (!bufferNote.IsPlaying(bufferPos) && _state != State.IDLE)
{
if (_state != State.RELEASING)
{
LOG.Debug("Start Release");
}
_state = State.RELEASING;
}
switch (_state)
{
case State.IDLE:
_level = 0;
break;
case State.ATTACKING:
_level = _attackBase + _level * _attackCoef;
if (_level >= 1.0f)
{
_level = 1.0f;
_state = State.DECAYING;
LOG.Debug("Start Decay");
}
break;
case State.DECAYING:
_level = _decayBase + _level * _decayCoef;
if (_level <= Sustain)
{
_level = Sustain;
_state = State.SUSTAINING;
LOG.Debug("Start Sustain");
}
break;
case State.RELEASING:
_level = _releaseBase + _level * _releaseCoef;
if (_level < DB90)
{
_level = 0;
_state = State.IDLE;
LOG.Debug("Start Idle");
}
break;
// default:
// break;
}
dest[bufferPos++] = _level;
// if (bufferPos > bufferNote.End)
// {
// bufferNote = _sequencer.GetBufferNote(bufferPos);
// if (bufferNote.Start > length)
// {
// Memory.ZeroMem(dest + bufferPos, length - bufferPos);
// return;
// }
// }
}
}
