Updated.
Here's a working code for controlling sound's decay (works in iOS and macOS):
import AVFoundation
import ARKit
class ViewController: UIViewController, AVAudioMixing {
@IBOutlet var sceneView: SCNView!
// @IBOutlet var sceneView: ARSCNView!
func destination(forMixer mixer: AVAudioNode,
bus: AVAudioNodeBus) -> AVAudioMixingDestination? {
return nil
}
var volume: Float = 0.0
var pan: Float = 0.0
var sourceMode: AVAudio3DMixingSourceMode = .bypass
var pointSourceInHeadMode: AVAudio3DMixingPointSourceInHeadMode = .bypass
var renderingAlgorithm = AVAudio3DMixingRenderingAlgorithm.sphericalHead
var rate: Float = 1.2
var reverbBlend: Float = 40.0
var obstruction: Float = -100.0
var occlusion: Float = -100.0
var position = AVAudio3DPoint(x: 0, y: 0, z: 10)
let audioNode = SCNNode()
override func viewDidLoad() {
super.viewDidLoad()
let myScene = SCNScene()
let cameraNode = SCNNode()
cameraNode.camera = SCNCamera()
cameraNode.position = SCNVector3(0, 0, 0)
myScene.rootNode.addChildNode(cameraNode)
// let sceneView = view as! SCNView
sceneView.scene = myScene
sceneView.backgroundColor = UIColor.orange
let myPath = Bundle.main.path(forResource: "Mono_Audio", ofType: "mp3")
let myURL = URL(fileURLWithPath: myPath!)
let mySource = SCNAudioSource(url: myURL)!
mySource.loops = true
mySource.isPositional = true // Positional Audio
mySource.shouldStream = false // FALSE for Positional Audio
mySource.volume = volume
mySource.reverbBlend = reverbBlend
mySource.rate = rate
mySource.load()
let player = SCNAudioPlayer(source: mySource)
let sphere: SCNGeometry = SCNSphere(radius: 0.1)
let sphereNode = SCNNode(geometry: sphere)
sphereNode.addChildNode(audioNode)
myScene.rootNode.addChildNode(sphereNode)
audioNode.addAudioPlayer(player)
sceneView.audioEnvironmentNode.distanceAttenuationParameters.maximumDistance = 2
sceneView.audioEnvironmentNode.distanceAttenuationParameters.referenceDistance = 0.1
sceneView.audioEnvironmentNode.renderingAlgorithm = .auto
// sceneView.audioEnvironmentNode.reverbParameters.enable = true
// sceneView.audioEnvironmentNode.reverbParameters.loadFactoryReverbPreset(.plate)
let hither = SCNAction.moveBy(x: 0, y: 0, z: 1, duration: 2)
let thither = SCNAction.moveBy(x: 0, y: 0, z: -1, duration: 2)
let sequence = SCNAction.sequence([hither, thither])
let loop = SCNAction.repeatForever(sequence)
sphereNode.runAction(loop)
}
}
And, yes, you're absolutely right – there are some obligatory settings.
But there are 7 of them:
use AVAudioMixing
protocol with its stubs (properties and methods).
use MONO
audio file.
use source.isPositional = true
.
use source.shouldStream = false
.
assign maximumDistance
value to distanceAttenuationParameters
property.
assign referenceDistance
value to distanceAttenuationParameters
property.
and location of mySource.load()
is very important in your code.
P.S. If the aforementioned tips didn't help you, then use additional instance properties to make your sound even quieter using a graph, obstacles and orientation of implicit listener:
var rolloffFactor: Float { get set } // attenuation's graph, default = 1
var obstruction: Float { get set } // default = 0.0
var occlusion: Float { get set } // default = 0.0
var listenerAngularOrientation: AVAudio3DAngularOrientation { get set } //(0,0,0)
It definitely works if you'll write it in Objective-C.
In this example the distance of audioNode
is 1 meter away from a listener
.