fading video over swift spritkit scene - ios

Question

I am porting a showroom application from as3/starling to a native swift iPad app.
I have 2 questions:
How can I fade a video over my spritekit content (from alpha 0 to 1).
How to control the iPad volume with an individual UI element without showing the iOS onscreen-volume notification graphic.

Answer 1

My first answer answers your initial question, and this answer is tailored to the subsequent questions that were posted in the comments. I feel that both answers are useful to the community, instead of combining into just one which I think would be confusing.
Here I implement a volume slider and a scrubbing slider that controls the VideoNode's AVPlayer object.. you get the full power of the AVPlayer but with the convenience of the SKVideoNode. Also, the volume for playing video is controlled without having to adjust the system volume and subsequent gray sound box pop-up:
import SpriteKit
import MediaPlayer
class GameScene: SKScene {
let seekSlider = UISlider(frame: CGRect(x: 0, y: 0, width: 200, height: 15))
let volSlider = UISlider(frame: CGRect(x: 0, y: 0, width: 200, height: 15))
// Because it takes time for us to load the video, we don't know it's duration,
// hence we don't know what the `.maximumValue` should be for the seekSlider
let defaultMax = Float(0.123456789)
var player: AVPlayer!
var videoNode: SKVideoNode!
func seekSliderChangedValue(sender: UISlider) {
// Wait for file to finish loading so we can get accurate end duration:
if sender.maximumValue == defaultMax {
if CMTimeGetSeconds(player.currentItem!.duration).isNaN { return }
else { sender.maximumValue = Float(CMTimeGetSeconds(player.currentItem!.duration)) }
}
let value = CMTimeMake(Int64(seekSlider.value), 1)
player.seek(to: value)
player.play()
}
func volSliderChangedValue(sender: UISlider) {
player.volume = sender.value
}
override func didMove(to view: SKView) {
removeAllChildren() // Delete this in your actual project.
// Add some labels:
let seekLabel = SKLabelNode(text: "Seek")
seekLabel.setScale(3)
seekLabel.verticalAlignmentMode = .center
seekLabel.position = CGPoint(x: frame.minX + seekLabel.frame.width/2,
y: frame.maxY - seekLabel.frame.height)
let volLabel = SKLabelNode(text: "Volume")
volLabel.setScale(3)
volLabel.verticalAlignmentMode = .center
volLabel.position = CGPoint(x: frame.minX + volLabel.frame.width/2,
y: frame.minY + volLabel.frame.height + volSlider.frame.height)
// Make player and node:
let url = Bundle.main.url(forResource: "sample", withExtension: "mp4")!
player = AVPlayer(url: url)
videoNode = SKVideoNode(avPlayer: player!)
//Configure seek slider:
seekSlider.addTarget(self, action: #selector(seekSliderChangedValue), for: UIControlEvents.valueChanged)
seekSlider.maximumValue = defaultMax
let seekOrigin = convertPoint(toView: CGPoint(x: seekLabel.frame.minX, y: seekLabel.frame.minY))
seekSlider.frame = CGRect(origin: seekOrigin, size: CGSize(width: 200, height: 15))
//Configure vol slider:
volSlider.addTarget(self, action: #selector(volSliderChangedValue), for: UIControlEvents.valueChanged)
volSlider.value = 1
let volOrigin = convertPoint(toView: CGPoint(x: volLabel.frame.minX, y: volLabel.frame.minY))
volSlider.frame = CGRect(origin: volOrigin, size: CGSize(width: 200, height: 15))
//Scene stuff:
view.addSubview(seekSlider)
view.addSubview(volSlider)
addChild(seekLabel)
addChild(volLabel)
addChild(videoNode)
// Start video and animation:
videoNode.alpha = 0
videoNode.play()
videoNode.run(.fadeIn(withDuration: 5))
}
}