Using positional audio

This lesson covers the playing sounds with DirectX Tool Kit for Audio using 3D positional audio effects.

Setup

First create a new project. For this lesson, use the DeviceResources variant described in Using DeviceResources, then use the instructions in Adding the DirectX Tool Kit, then Adding the DirectX Tool Kit for Audio, and finally Adding audio to your project which we will use for this lesson.

Background

Games provide an immersive visual and audio experience, and often use 3D audio effects to enhance the audio. The effect modifies the speaker position, pitch, and volume of a sound to provide audial cues to place it in the 3D environment. XAudio2 itself provides the ability to specify a complex per-channel volume mapping, pitch modification, and other parameters to generate these 3D effects, but does not perform the computations. The X3DAudio library is used by DirectX Tool Kit for Audio to compute the virtual placement of the sound.

See Microsoft Docs for more information on X3DAudio.

Sounds

Save the this file to your new project's folder: heli.wav. Use the top menu and select Project / Add Existing Item.... Select the heli.wav file and hit "OK".

In the Game.h file, add the following variables to the bottom of the Game class's private declarations:

std::unique_ptr<DirectX::SoundEffect> m_soundEffect;

In Game.cpp, add to the end of Initialize:

m_soundEffect = std::make_unique<SoundEffect>( m_audEngine.get(), L"heli.wav" );

Build and run. No sounds will be heard, but the audio file is loaded.

Troubleshooting: If you get a runtime exception, then you may have the .wav file in the wrong folder, have modified the "Working Directory" in the "Debugging" configuration settings, or otherwise changed the expected paths at runtime of the application. You should set a break-point on std::make_unique<SoundEffect> and step into the code to find the exact problem.