The Attenuation Class

Creating the Class

To create a sound attenuation class, right click anywhere in your content browser, navigate to the sounds section and click Sound Attenuation.

Give your new Sound Attenuation class a name and remember it as we will be using it later in the guide.

I named mine Tutorial Sound Attenuation.

Class Settings

Opening your new Sound Attenuation class will show these settings:

There are many settings that can be changed to modulate your audio to make it very realistic.

For simple audio attenuation we only need these settings:

For the demonstration video at the end of the guide I will be using these exact settings.

Attenuation Function

The attenuation function determines how the volume is changed over distance.

• Linear reduces the volume equal to the distance.
• Logarithmic reduces the volume much faster over distance.
• Inverse has the fastest volume drop off.
• Log Reverse reduces the volume very slowly until a large distance then it drops off very quickly.
• Natural sound reduces the volume to imitate how sound works in the real world.
• Custom is for creating your own curves. This isn’t recommended as it can get quite complicated.

For the majority of your sounds I recommend to use the Logarithmic function. It creates easily locatable sound and prevents far sounds from being unnecessarily loud.

Attenuation Shape

Attenuation shapes restrict sounds to a specific shape. This prevents sounds from leaking out of a specific environment.

• Sphere is for most sounds.
• Capsule is for thin and round environments.
• Box is for cuboid shaped buildings.
• Cone is for projecting sound at a specific area or player.

Inner Radius

The inner radius is the size of the sphere that represents your sound at full volume.

Any player inside this sphere will hear the sound without any volume reduction.

Falloff Distance

The falloff distance is the distance the player needs to be for the audio volume to be zero.

The volume reaches zero using the attenuation function setup earlier.

Enable Volume Attenuation

This setting controls if you want the audio to lower in volume over distance. We need this to be checked.

Attenuating Audio

Applying the Attenuation Class

To play sounds with your newly setup attenuation class, create a “Play Sound at Location” node.

Set the Sound input pin to which ever sound file you want to play.

Create a “Get Actor Location” node and connect it to the Location pin on the “Play Sound at Location” node.

Click the box with the triangle to expose the additional audio settings.

The additional setting that we need is called “Attenuation Settings”. Set this to your attenuation class created at the start of the guide.

Now your sound will use the Sound Attenuation class when played and will be specialized in the world at the location specified.

Video Demonstration

Conclusion

These are just the basics of attenuation in Unreal Engine 4. I recommend spending time to figure out which is the best attenuation function and attenuation shape for the atmosphere you want to create.

To see the individual plotted graphs for each attenuation function click here for the official Unreal Engine 4 wiki page.

The post Simple Audio Attenuation in Unreal Engine 4 appeared first on Couch Learn.

Configuration

Config Directory

All files that we will be creating or editing will be in the config folder. To find this folder navigate to your project folder and open the config folder.

Enabling the Features

Here I will show you how to enable the new audio engine for each platform.

You only need the folder and files for the platform that you wish to build your game for.

Here are the platforms and their folder names:

Inside the platform folder that you wish to use we need to create the configuration file for that platform.

To create these folders right click in the folder and create a new text document. From there you can change the name and extension to make it work with the engine.

Configuration File Names

Windows Folder – WindowsEngine.ini

MacOS Folder – MacEngine.ini

iOS Folder – IOSEngine.ini

Android Folder – AndroidEngine.ini

Make sure the extension is exactly .ini for the engine to understand the file.

If this alert box shows press YES to create the file.

If done correctly the file type should be “Configuration setting”.

To edit .ini files, right click the file and click on the edit option.

WindowsEngine.ini

Open WindowsEngine.ini, copy and paste this into the text editor then save and then quit:

[Audio]
AudioDeviceModuleName=AudioMixerXAudio2 

MacEngine.ini

Open MacEngine.ini, open copy and paste this into the text editor then save and then quit:

[Audio]
AudioDeviceModuleName=AudioMixerAudioUnit

IOSEngine.ini

Open IOSEngine.ini, copy and paste this into the text editor then save and then quit:

[Audio]
AudioDeviceModuleName=AudioMixerAudioUnit

AndroidEngine.ini

Open AndroidEngine.ini, copy and paste this into the text editor then save and then quit:

[Audio]
AudioDeviceModuleName=AudioMixerAndroid

This is all you need to tell the engine what audio engine to use. The next step is to enable the plugins so the editor gives you access to the blueprint nodes and additional audio blueprint classes.

Enabling the Plugins

To access the plugin browser press Edit then plugins from the drop down menu.

The two plugins we need to enable are in the Audio section of the plugins browser:

Enable the sound utilities and Synthesis and DSP effects plugins

The final step left to do is to restart the editor.

Conclusion

You are all set! There are many powerful tools in the new audio engine for you to now use in your new or existing projects. My main use for the new audio engine is to control the VOIPTalker component with audio effects through a source effect chain.

As the new audio engine is experimental not much documentation exists. I encourage you to create a new blueprint and look through all of the synth nodes and make something new. The best way to learn how these systems work is to dive headfirst and play around with it.

The post How to enable the new audio engine in your Unreal Engine 4 Project appeared first on Couch Learn.