internal SoundInstance(Sound staticSound, AudioListener listener, bool forceLoadInMemory)
{
Listener = listener;
engine = staticSound.AudioEngine;
sound = staticSound;
spatialized = staticSound.Spatialized;
var streamed = staticSound.StreamFromDisk && !forceLoadInMemory;
if (engine.State == AudioEngineState.Invalidated)
return;
Source = AudioLayer.SourceCreate(listener.Listener, staticSound.SampleRate, streamed ? CompressedSoundSource.NumberOfBuffers : 1, staticSound.Channels == 1, spatialized, streamed);
if (Source.Ptr == IntPtr.Zero)
{
throw new Exception("Failed to create an AudioLayer Source");
}
if (streamed)
{
soundSource = new CompressedSoundSource(this, staticSound.CompressedDataUrl, staticSound.NumberOfPackets, staticSound.SampleRate, staticSound.Channels, staticSound.MaxPacketLength);
}
else
{
if (sound.PreloadedBuffer.Ptr == IntPtr.Zero)
{
staticSound.LoadSoundInMemory(); //this should be already loaded by the serializer, but in the case of forceLoadInMemory might not be the case yet.
}
AudioLayer.SourceSetBuffer(Source, staticSound.PreloadedBuffer);
}
ResetStateToDefault();
}
/// <summary>
/// Initialize audio engine
/// </summary>
internal virtual void InitializeAudioEngine()
{
AudioDevice = AudioLayer.Create(audioDevice.Name == "default" ? null : audioDevice.Name);
if (AudioDevice.Ptr == IntPtr.Zero)
{
State = AudioEngineState.Invalidated;
}
DefaultListener = new AudioListener(this);
}
private void Apply3DImpl(AudioListener listener, AudioEmitter emitter)
{
var vectDirWorldBase = emitter.Position - listener.Position;
var baseChangeMat = Matrix.Identity;
baseChangeMat.Row2 = new Vector4(listener.Up, 0);
baseChangeMat.Row3 = new Vector4(listener.Forward, 0);
baseChangeMat.Row1 = new Vector4(Vector3.Cross(listener.Up, listener.Forward), 0);
var vectDirListBase = Vector3.TransformNormal(vectDirWorldBase, baseChangeMat);
var azimut = 180f * (float)(Math.Atan2(vectDirListBase.X, vectDirListBase.Z)/Math.PI);
var elevation = 180f * (float)(Math.Atan2(vectDirListBase.Y, new Vector2(vectDirListBase.X, vectDirListBase.Z).Length())/Math.PI);
var distance = vectDirListBase.Length();
ComputeDopplerFactor(listener,emitter);
AudioVoice.Apply3D(azimut, elevation, distance / emitter.DistanceScale, MathUtil.Clamp((float)Math.Pow(2, Pitch) * dopplerPitchFactor, 0.5f, 2f));
}
/// <summary>
/// Create a new sound effect instance of the sound effect.
/// The audio data are shared between the instances so that useless memory copies is avoided.
/// Each instance that can be played and localized independently from others.
/// </summary>
/// <returns>A new sound instance</returns>
/// <exception cref="ObjectDisposedException">The sound has already been disposed</exception>
public SoundInstance CreateInstance(AudioListener listener = null, bool forceLoadInMemory = false)
{
if (listener == null)
{
listener = AudioEngine.DefaultListener;
}
CheckNotDisposed();
var newInstance = new SoundInstance(this, listener, forceLoadInMemory) { Name = Name + " - Instance " + intancesCreationCount };
RegisterInstance(newInstance);
++intancesCreationCount;
return newInstance;
}
/// <summary>
/// Initializes a new instance of the <see cref="SoundInstance"/> class using a dynamic sound source.
/// </summary>
/// <param name="engine">The audio engine that will be used to play this instance</param>
/// <param name="listener">The listener of this instance</param>
/// <param name="dynamicSoundSource">The source from where the PCM data will be fetched</param>
/// <param name="sampleRate">The sample rate of this audio stream</param>
/// <param name="mono">Set to true if the souce is mono, false if stereo</param>
/// <param name="spatialized">If the SoundInstance will be used for spatialized audio set to true, if not false, if true mono must also be true</param>
public SoundInstance(AudioEngine engine, AudioListener listener, DynamicSoundSource dynamicSoundSource, int sampleRate, bool mono, bool spatialized = false)
{
Listener = listener;
this.engine = engine;
this.spatialized = spatialized;
soundSource = dynamicSoundSource;
if (engine.State == AudioEngineState.Invalidated)
return;
Source = AudioLayer.SourceCreate(listener.Listener, sampleRate, dynamicSoundSource.MaxNumberOfBuffers, mono, spatialized, true);
if (Source.Ptr == IntPtr.Zero)
{
throw new Exception("Failed to create an AudioLayer Source");
}
ResetStateToDefault();
}
internal void Apply3DImpl(AudioListener listener, AudioEmitter emitter)
{
//////////////////////////////////////////////////////////////
// 1. First let's calculate the parameters to set to the voice
var inputChannels = soundEffect.WaveFormat.Channels;
var outputChannels = MasterVoice.VoiceDetails.InputChannelCount;
if (inputChannels != 1 || outputChannels != 2)
throw new AudioSystemInternalException("Error in Apply3DImpl only mono sounds are supposed to be localizable");
var list = new Listener
{
Position = listener.Position.ToSharpDX(),
Velocity = listener.Velocity.ToSharpDX(),
OrientFront = listener.Forward.ToSharpDX(),
OrientTop = listener.Up.ToSharpDX()
};
var emit = new Emitter
{
Position = emitter.Position.ToSharpDX(),
Velocity = emitter.Velocity.ToSharpDX(),
DopplerScaler = emitter.DopplerScale,
CurveDistanceScaler = emitter.DistanceScale,
ChannelRadius = 0f, // Multi-channels localizable sound are considered as source of multiple sounds coming from the same location.
ChannelCount = inputChannels
};
var dspSettings = new DspSettings(inputChannels, outputChannels);
AudioEngine.X3DAudio.Calculate(list, emit, CalculateFlags.Matrix | CalculateFlags.LpfDirect, dspSettings);
/////////////////////////////////////////////////////////////
// 2. Now let's set the voice parameters to simulate a 3D voice.
// 2.1 The Doppler effect due to the difference of speed between the emitter and listener
ComputeDopplerFactor(listener, emitter);
UpdatePitch();
// 2.2 The channel attenuations due to the source localization.
localizationChannelVolumes = new[] { dspSettings.MatrixCoefficients[0], dspSettings.MatrixCoefficients[1] }; // only mono sound can be localized so matrix should be 2*1
UpdateStereoVolumes();
}
private void Apply3DImpl(AudioListener listener, AudioEmitter emitter)
{
// Since android has no function available to perform sound 3D localization by default, here we try to mimic the behaviour of XAudio2
// After an analysis of the XAudio2 left/right stereo balance with respect to 3D world position,
// it could be found the volume repartition is symmetric to the Up/Down and Front/Back planes.
// Moreover the left/right repartition seems to follow a third degree polynomial function:
// Volume_left(a) = 2(c-1)*a^3 - 3(c-1)*a^2 + c*a , where c is a constant close to c = 1.45f and a is the angle normalized bwt [0,1]
// Volume_right(a) = 1-Volume_left(a)
// As for signal attenuation wrt distance the model follows a simple inverse square law function as explained in XAudio2 documentation
// ( http://msdn.microsoft.com/en-us/library/windows/desktop/microsoft.directx_sdk.x3daudio.x3daudio_emitter(v=vs.85).aspx )
// Volume(d) = 1 , if d <= ScaleDistance where d is the distance to the listener
// Volume(d) = ScaleDistance / d , if d >= ScaleDistance where d is the distance to the listener
// 1. Attenuation due to distance.
var vecListEmit = emitter.Position - listener.Position;
var distListEmit = vecListEmit.Length();
var attenuationFactor = distListEmit <= emitter.DistanceScale ? 1f : emitter.DistanceScale / distListEmit;
// 2. Left/Right balance.
var repartRight = 0.5f;
var worldToList = Matrix.Identity;
var rightVec = Vector3.Cross(listener.Forward, listener.Up);
worldToList.Column1 = new Vector4(rightVec, 0);
worldToList.Column2 = new Vector4(listener.Forward, 0);
worldToList.Column3 = new Vector4(listener.Up, 0);
var vecListEmitListBase = Vector3.TransformNormal(vecListEmit, worldToList);
var vecListEmitListBase2 = (Vector2)vecListEmitListBase;
if (vecListEmitListBase2.Length() > 0)
{
const float c = 1.45f;
var absAlpha = Math.Abs(Math.Atan2(vecListEmitListBase2.Y, vecListEmitListBase2.X));
var normAlpha = (float)(absAlpha / (Math.PI / 2));
if (absAlpha > Math.PI / 2) normAlpha = 2 - normAlpha;
repartRight = 0.5f * (2 * (c - 1) * normAlpha * normAlpha * normAlpha - 3 * (c - 1) * normAlpha * normAlpha * normAlpha + c * normAlpha);
if (absAlpha > Math.PI / 2) repartRight = 1 - repartRight;
}
// Set the volumes.
localizationChannelVolumes = new[] { attenuationFactor * (1f - repartRight), attenuationFactor * repartRight };
UpdateStereoVolumes();
// 3. Calculation of the Doppler effect
ComputeDopplerFactor(listener, emitter);
UpdatePitch();
}
public void Apply3D(AudioListener listener, AudioEmitter emitter)
{
DefaultInstance.Apply3D(listener, emitter);
}
private void ComputeDopplerFactor(AudioListener listener, AudioEmitter emitter)
{
// To evaluate the Doppler effect we calculate the distance to the listener from one wave to the next one and divide it by the sound speed
// we use 343m/s for the sound speed which correspond to the sound speed in the air.
// we use 600Hz for the sound frequency which correspond to the middle of the human hearable sounds frequencies.
const float SoundSpeed = 343f;
const float SoundFreq = 600f;
const float SoundPeriod = 1 / SoundFreq;
// avoid useless calculations.
if (emitter.DopplerScale <= float.Epsilon || (emitter.Velocity == Vector3.Zero && listener.Velocity == Vector3.Zero))
{
dopplerPitchFactor = 1f;
return;
}
var vecListEmit = emitter.Position - listener.Position;
var distListEmit = vecListEmit.Length();
var vecListEmitSpeed = emitter.Velocity - listener.Velocity;
if (Vector3.Dot(vecListEmitSpeed, Vector3.Normalize(vecListEmit)) < -SoundSpeed) // emitter and listener are getting closer more quickly than the speed of the sound.
{
dopplerPitchFactor = float.PositiveInfinity; // will be clamped later
return;
}
var timeSinceLastWaveArrived = 0f; // time elapsed since the previous wave arrived to the listener.
var lastWaveDistToListener = 0f; // the distance that the last wave still have to travel to arrive to the listener.
const float DistLastWave = SoundPeriod * SoundSpeed; // distance traveled by the previous wave.
if (DistLastWave > distListEmit)
timeSinceLastWaveArrived = (DistLastWave - distListEmit) / SoundSpeed;
else
lastWaveDistToListener = distListEmit - DistLastWave;
var nextVecListEmit = vecListEmit + SoundPeriod * vecListEmitSpeed;
var nextWaveDistToListener = nextVecListEmit.Length();
var timeBetweenTwoWaves = timeSinceLastWaveArrived + (nextWaveDistToListener - lastWaveDistToListener) / SoundSpeed;
var apparentFrequency = 1 / timeBetweenTwoWaves;
dopplerPitchFactor = (float) Math.Pow(apparentFrequency / SoundFreq, emitter.DopplerScale);
}
public void Apply3D(AudioListener listener, AudioEmitter emitter)
{
CheckNotDisposed();
if (listener == null)
throw new ArgumentNullException("listener");
if(emitter == null)
throw new ArgumentNullException("emitter");
if(soundEffect.WaveFormat.Channels > 1)
throw new InvalidOperationException("Apply3D cannot be used on multi-channels sounds.");
// reset Pan its default values.
if (Pan != 0)
Pan = 0;
if (EngineState != AudioEngineState.Invalidated)
Apply3DImpl(listener, emitter);
}
internal void Apply3DImpl(AudioListener listener, AudioEmitter emitter)
{
throw new NotImplementedException();
}
public void Apply3D(AudioListener listener, AudioEmitter emitter)
{
DefaultInstance.Apply3D(listener, emitter);
}
