/// <summary>
/// Pans a sound.
/// This method was initially written using the guide at https://docs.microsoft.com/en-us/windows/win32/xaudio2/how-to--pan-a-sound
/// The code has finally been improved thanks to the MonoGame framework code: https://github.com/MonoGame/MonoGame
/// </summary>
/// <param name="sound">The sound to pan.</param>
/// <param name="pan">The value by which to pan the sound. -1.0f is completely left, and 1.0f is completely right. 0.0f is center.</param>
public static void setPan(ExtendedAudioBuffer sound, float pan)
{
SpeakerConfiguration mask;
if (mainSoundDevice.Version == XAudio2Version.Version27)
{
WaveFormatExtensible deviceFormat = mainSoundDevice.GetDeviceDetails(0).OutputFormat;
mask = (SpeakerConfiguration)deviceFormat.ChannelMask;
}
else
{
mask = (SpeakerConfiguration)mainMasteringVoice.ChannelMask;
}
VoiceDetails soundDetails = sound.getVoiceDetails();
VoiceDetails masteringDetails = mainMasteringVoice.VoiceDetails;
int srcChannelCount = soundDetails.InputChannelCount;
int dstChannelCount = masteringDetails.InputChannelCount;
// Create an array to hold the output matrix. Warning : the minimum size of the output matrix is the number of channels in the source voice times the number of channels in the output voice.
// Note that the outputMatrix indices are placed in the same order as the SharpDX.Multimedia.Speakers enum.
// Don't forget there are two times more cells in the matrix if the source sound is stereo)
float[] outputMatrix = new float[srcChannelCount * dstChannelCount];
Array.Clear(outputMatrix, 0, outputMatrix.Length);
// From there, we'll hope that the sound file is either mono or stereo. If the WAV had more than 2 channels, it would be to difficult to handle.
// Similarly, we'll also only output to the front-left and front-right speakers for simplicity, e.g. like the XNA framework does.
if (srcChannelCount == 1) // Mono source
{
// Left/Right output levels:
// Pan -1.0: L = 1.0, R = 0.0
// Pan 0.0: L = 1.0, R = 1.0
// Pan +1.0: L = 0.0, R = 1.0
outputMatrix[0] = (pan > 0f) ? ((1f - pan)) : 1f; // Front-left output
outputMatrix[1] = (pan < 0f) ? ((1f + pan)) : 1f; // Front-right output
}
else if (srcChannelCount == 2) // Stereo source
{
// Left/Right input (Li/Ri) mix for Left/Right outputs (Lo/Ro):
// Pan -1.0: Lo = 0.5Li + 0.5Ri, Ro = 0.0Li + 0.0Ri
// Pan 0.0: Lo = 1.0Li + 0.0Ri, Ro = 0.0Li + 1.0Ri
// Pan +1.0: Lo = 0.0Li + 0.0Ri, Ro = 0.5Li + 0.5Ri
if (pan <= 0f)
{
outputMatrix[0] = 1f + pan * 0.5f; // Front-left output, Left input
outputMatrix[1] = -pan * 0.5f; // Front-left output, Right input
outputMatrix[2] = 0f; // Front-right output, Left input
outputMatrix[3] = 1f + pan; // Front-right output, Right input
}
else
{
outputMatrix[0] = 1f - pan; // Front-left output, Left input
outputMatrix[1] = 0f; // Front-left output, Right input
outputMatrix[2] = pan * 0.5f; // Front-right output, Left input
outputMatrix[3] = 1f - pan * 0.5f; // Front-right output, Right input
}
}
sound.setOutputMatrix(soundDetails.InputChannelCount, masteringDetails.InputChannelCount, outputMatrix);
}
/// <summary>
/// Pans a sound.
/// This method was written using the guide at https://docs.microsoft.com/en-us/windows/win32/xaudio2/how-to--pan-a-sound
/// </summary>
/// <param name="sound">The sound to pan.</param>
/// <param name="pan">The value by which to pan the sound. -1.0f is completely left, and 1.0f is completely right. 0.0f is center.</param>
public static void setPan(ExtendedAudioBuffer sound, float pan)
{
SpeakerConfiguration mask = (SpeakerConfiguration)mainMasteringVoice.ChannelMask;
float[] outputMatrix = new float[8];
float left = 0.5f - pan / 2;
float right = 0.5f + pan / 2;
switch (mask)
{
case SpeakerConfiguration.mono:
outputMatrix[0] = 1.0f;
break;
case SpeakerConfiguration.stereo:
case SpeakerConfiguration.twoPointOne:
case SpeakerConfiguration.surround:
outputMatrix[0] = left;
outputMatrix[1] = right;
break;
case SpeakerConfiguration.quad:
outputMatrix[0] = outputMatrix[2] = left;
outputMatrix[1] = outputMatrix[3] = right;
break;
case SpeakerConfiguration.fourPointOne:
outputMatrix[0] = outputMatrix[3] = left;
outputMatrix[1] = outputMatrix[4] = right;
break;
case SpeakerConfiguration.fivePointOne:
case SpeakerConfiguration.sevenPointOne:
case SpeakerConfiguration.fivePointOneSurround:
outputMatrix[0] = outputMatrix[4] = left;
outputMatrix[1] = outputMatrix[5] = right;
break;
case SpeakerConfiguration.sevenPointOneSurround:
outputMatrix[0] = outputMatrix[4] = outputMatrix[6] = left;
outputMatrix[1] = outputMatrix[5] = outputMatrix[7] = right;
break;
}
VoiceDetails soundDetails = sound.getVoiceDetails();
VoiceDetails masteringDetails = mainMasteringVoice.VoiceDetails;
sound.setOutputMatrix(soundDetails.InputChannelCount, masteringDetails.InputChannelCount, outputMatrix);
}
