/// <summary>
/// Render callback for the output node. Can simulataneously write to a file.
/// </summary>
/// <returns>The render delegate.</returns>
/// <param name="actionFlags">Action flags.</param>
/// <param name="timeStamp">Time stamp.</param>
/// <param name="busNumber">Bus number.</param>
/// <param name="numberFrames">Number frames.</param>
/// <param name="data">Data.</param>
AudioUnitStatus OutputRenderDelegate(AudioUnitRenderActionFlags actionFlags, AudioTimeStamp timeStamp, uint busNumber, uint numberFrames, AudioBuffers data)
{
// propagate tempo change on start of a new cycle
if (_tempoChanged)
{
PropagateTempoChange(_tempoChangeRatio);
_tempoChanged = false;
}
var e = MixerNode.Render(ref actionFlags, timeStamp, busNumber, numberFrames, data);
cycle++;
// check for a queued layer change
if (Metronome.Instance.NeedToChangeLayer == true)
{
Metronome.Instance.CycleToChange = cycle;
Metronome.Instance.NeedToChangeLayer = false;
Metronome.Instance.ChangeLayerTurnstyle.Set();
}
else if (Metronome.Instance.NeedToChangeLayer == null)
{
// top off the fat forward
double cycleDiff = cycle - Metronome.Instance.CycleToChange;
Metronome.Instance.FastForwardChangedLayers(cycleDiff);
foreach (KeyValuePair <int, Layer> pair in Metronome.Instance.LayersToChange)
{
Layer copy = pair.Value;
Layer real = Metronome.Instance.Layers[pair.Key];
int numberRemoved = 0;
bool isMuted = false;
// remove old sources
foreach (IStreamProvider src in real.GetAllStreams())
{
RemoveStream(src);
src.Dispose();
numberRemoved++;
isMuted = src.IsMuted;
}
// transfer sources to real layer
real.AudioSources = copy.AudioSources;
real.BaseAudioSource = copy.BaseAudioSource;
real.PitchSource = copy.PitchSource;
real.BaseSourceName = copy.BaseSourceName;
real.HasHiHatOpen = copy.HasHiHatOpen;
real.HasHiHatClosed = copy.HasHiHatClosed;
real.Beat = copy.Beat;
foreach (IStreamProvider src in real.GetAllStreams().OrderBy(x => x.Info.HiHatStatus != StreamInfoProvider.HiHatStatuses.Down))
{
src.IsMuted = isMuted;
src.Layer = real;
if (numberRemoved <= 0)
{
// it crashes if we try to add a rendercallback for preexisting bus
Metronome.Instance.AddAudioSource(src);
}
else
{
Streams.Add(src);
}
numberRemoved--;
}
copy.AudioSources = null;
copy.BaseAudioSource = null;
copy.PitchSource = null;
copy.Beat = null;
Metronome.Instance.Layers.Remove(copy);
foreach (IStreamProvider src in Streams)
{
// keep muting consistent when shuffling buffer indexs
if (src.IsMuted)
{
EnableInput(src, false);
}
else
{
EnableInput(src, true);
}
SetPan(src, src.Pan);
SetInputVolume(src, (float)src.Volume);
}
}
Metronome.Instance.LayersToChange.Clear();
Metronome.Instance.NeedToChangeLayer = false;
// trigger beat changed event
AppKit.NSApplication.SharedApplication.BeginInvokeOnMainThread(
() => { Metronome.Instance.OnBeatChanged(null); });
}
// check if recording to file
if (_fileRecordingQueued)
{
// convert the buffer
using (AudioBuffers convBuffer = new AudioBuffers(1))
{
convBuffer[0] = new AudioBuffer()
{
DataByteSize = data[0].DataByteSize,
NumberChannels = 1,
Data = Marshal.AllocHGlobal(sizeof(float) * data[0].DataByteSize)
};
_converter.ConvertComplexBuffer((int)numberFrames, data, convBuffer);
_file.Write(numberFrames, convBuffer);
}
}
return(AudioUnitStatus.OK);
}
/// <summary>
/// Renders the given number of seconds to the given wav file
/// </summary>
/// <param name="fileName">File name.</param>
/// <param name="seconds">Seconds.</param>
public void RenderToFile(string fileName, double seconds)
{
long samples = (long)(seconds * Metronome.SampleRate);
var inputStream = MixerNode.GetAudioFormat(AudioUnitScopeType.Output);
var outputStream = AudioStreamBasicDescription.CreateLinearPCM(44100, 2);
AudioConverter converter = AudioConverter.Create(inputStream, outputStream);
var file = ExtAudioFile.CreateWithUrl(
new Foundation.NSUrl(fileName, false),
AudioFileType.WAVE,
outputStream,
AudioFileFlags.EraseFlags,
out ExtAudioFileError e
);
long samplesRead = 0;
// initialize the buffers
var buffers = new AudioBuffers(2);
buffers[0] = new AudioBuffer()
{
DataByteSize = BufferSize * 4,
NumberChannels = 1,
Data = Marshal.AllocHGlobal(sizeof(float) * BufferSize)
};
buffers[1] = new AudioBuffer()
{
DataByteSize = BufferSize * 4,
NumberChannels = 1,
Data = Marshal.AllocHGlobal(sizeof(float) * BufferSize)
};
var convBuffers = new AudioBuffers(1);
convBuffers[0] = new AudioBuffer()
{
DataByteSize = BufferSize * 4,
NumberChannels = 2,
Data = Marshal.AllocHGlobal(sizeof(float) * BufferSize)
};
while (samples > 0)
{
int numSamples = (int)(Math.Min(BufferSize, samples));
// get samples from the mixer
Render((uint)numSamples, buffers, samplesRead);
// conver to the file's format
converter.ConvertComplexBuffer(numSamples, buffers, convBuffers);
// write samples to the file
var error = file.Write((uint)numSamples, convBuffers);
if (error != ExtAudioFileError.OK)
{
throw new ApplicationException();
}
samples -= BufferSize;
samplesRead += numSamples;
}
buffers.Dispose();
convBuffers.Dispose();
converter.Dispose();
file.Dispose();
}
