public AUv3FilterDemo(AudioComponentDescription description, AudioComponentInstantiationOptions options, out NSError error) :
base(description, options, out error)
{
var defaultFormat = new AVAudioFormat(44100.0, 2);
Kernel.Init((int)defaultFormat.ChannelCount, defaultFormat.SampleRate);
AUParameter cutoffParam = AUParameterTree.CreateParameter(
"cutoff", "Cutoff", 0, 12, 2000,
AudioUnitParameterUnit.Hertz, null,
0, null, null
);
AUParameter resonanceParam = AUParameterTree.CreateParameter(
"resonance", "Resonance", 1, -20, 20,
AudioUnitParameterUnit.Decibels, null,
0, null, null
);
cutoffParam.Value = 400f;
resonanceParam.Value = -5.0f;
Kernel.SetParameter((ulong)FilterParam.Cutoff, cutoffParam.Value);
Kernel.SetParameter((ulong)FilterParam.Resonance, resonanceParam.Value);
ParameterTree = AUParameterTree.CreateTree(
new [] {
cutoffParam,
resonanceParam
}
);
inputBus.Init(defaultFormat, 8);
NSError err;
outputBus = new AUAudioUnitBus(defaultFormat, out err);
inputBusArray = new AUAudioUnitBusArray(this, AUAudioUnitBusType.Input, new [] { inputBus.Bus });
outputBusArray = new AUAudioUnitBusArray(this, AUAudioUnitBusType.Output, new [] { outputBus });
var filterKernel = Kernel;
ParameterTree.ImplementorValueObserver = (param, value) => filterKernel.SetParameter(param.Address, value);
ParameterTree.ImplementorValueProvider = param => filterKernel.GetParameter((nuint)param.Address);
ParameterTree.ImplementorStringFromValueCallback = (AUParameter param, ref float?value) => {
switch (param.Address)
{
case (ulong)FilterParam.Cutoff:
return(param.Value.ToString());
case (ulong)FilterParam.Resonance:
return(param.Value.ToString());
default:
return("?");
}
};
MaximumFramesToRender = 512;
}
public MyAudioUnit(AudioComponentDescription description, AudioComponentInstantiationOptions options, out NSError error)
: base(description, options, out error)
{
// Create parameter objects.
AUParameter param1 = AUParameterTree.CreateParameter(
"param1",
"Parameter 1",
0, 0, 100,
AudioUnitParameterUnit.Percent,
string.Empty,
0, null, null
);
// Initialize the parameter values.
param1.Value = .5f;
// Create the parameter tree.
parameterTree = AUParameterTree.CreateTree(new[] { param1 });
// Create the input and output busses.
// Create the input and output bus arrays.
// A function to provide string representations of parameter values.
parameterTree.ImplementorStringFromValueCallback = (AUParameter param, ref float?value) =>
{
switch (param.Address)
{
case 0:
return((NSString)value?.ToString());
default:
return(new NSString("?"));
}
};
MaximumFramesToRender = 512;
}
