I am trying to download the volume to a SKAudioNode using the following code:
audioNode?.run(SKAction.changeVolume(to: 0.0, duration: 3.0 ))
You should lower the volume to 0.0 in 3.0 seconds. But the sound stops immediately.
Is it possible to do this in SpriteKit?
I found the following solution:
Swift 3:
extension SKAction {
// All the change... actions for SKAudioNode are broken. They do not work with looped audio. These are replacements
public class func _changeVolumeTo(endVolume: Float, duration: NSTimeInterval) -> SKAction
{
var startVolume : Float!
var distance : Float!
let action = SKAction.customActionWithDuration(duration)
{
node, elapsedTime in
if let soundNode = node as? SoundNode
{
if startVolume == nil
{
startVolume = soundNode.volume
distance = endVolume - startVolume
}
let fraction = Float(elapsedTime / CGFloat(duration))
let newVolume = startVolume + (distance * fraction)
soundNode.volume = newVolume
}
}
return action
}
}
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