Swift spritekit didbegincontact being called with delay - swift

Question

This is my GameScene code.
class GameScene: SKScene, SKPhysicsContactDelegate {
let orcWidth = UIScreen.main.bounds.width / 5
var orcCategory:UInt32 = 0x1 << 0
var knightCategory:UInt32 = 0x1 << 1
private var orc = SKSpriteNode()
private var knight = SKSpriteNode()
private var orcWalkingFrames: [SKTexture] = []
private var knightIdleFrames: [SKTexture] = []
private var knightAttackFrame: [SKTexture] = []
var background = SKSpriteNode(imageNamed: "game_background1")
override func didMove(to view: SKView) {
physicsWorld.contactDelegate = self
physicsWorld.gravity = CGVector(dx: 0, dy: 0)
setupbackground()
startGame()
}
func setupbackground() {
background.zPosition = 0
background.size = self.frame.size
background.position = CGPoint(x: frame.size.width / 2, y: frame.size.height / 2)
addChild(background)
}
func startGame() {
buildRandomOrcs()
buildKnight()
}
func stopGame() {
}
func buildOrc(yposition: CGFloat) {
var orcWalkFrames: [SKTexture] = []
let orcAnimatedAtlas = SKTextureAtlas(named: "OrcWalking")
let numImages = orcAnimatedAtlas.textureNames.count
for i in 0...numImages - 1 {
let orcTextureName = "0_Orc_Walking_\(i)"
orcWalkFrames.append(orcAnimatedAtlas.textureNamed(orcTextureName))
}
self.orcWalkingFrames = orcWalkFrames
let firstFrameTexture = orcWalkingFrames[0]
orc = SKSpriteNode(texture: firstFrameTexture)
orc.name = "orc"
orc.position = CGPoint(x: frame.minX-orcWidth/2, y: yposition)
self.orc.zPosition = CGFloat(self.children.count)
orc.scale(to: CGSize(width: orcWidth, height: orcWidth))
orc.physicsBody = SKPhysicsBody(rectangleOf: orc.size, center: orc.position)
orc.physicsBody?.affectedByGravity = false
orc.physicsBody?.isDynamic = true
orc.physicsBody?.categoryBitMask = orcCategory
orc.physicsBody?.contactTestBitMask = knightCategory
orc.physicsBody?.collisionBitMask = knightCategory
addChild(orc)
walkOrc()
moveOrcForward()
}
func buildKnight() {
var knightIdleFrames: [SKTexture] = []
let knightIdleAtlas = SKTextureAtlas(named: "KnightIdle")
let numImages = knightIdleAtlas.textureNames.count
for i in 0...numImages - 1 {
let orcTextureName = "_IDLE_00\(i)"
knightIdleFrames.append(knightIdleAtlas.textureNamed(orcTextureName))
}
self.knightIdleFrames = knightIdleFrames
let firstFrameTexture = knightIdleFrames[0]
knight = SKSpriteNode(texture: firstFrameTexture)
knight.name = "knight"
knight.position = CGPoint(x: frame.maxX-orcWidth/2, y: frame.midY)
self.knight.zPosition = 1
knight.scale(to: CGSize(width: -orcWidth, height: orcWidth))
knight.physicsBody = SKPhysicsBody(rectangleOf: knight.size, center: knight.position)
knight.physicsBody?.affectedByGravity = false
knight.physicsBody?.isDynamic = false
knight.physicsBody?.categoryBitMask = knightCategory
knight.physicsBody?.contactTestBitMask = orcCategory
knight.physicsBody?.collisionBitMask = orcCategory
addChild(knight)
idleKnight()
}
func idleKnight() {
knight.run(SKAction.repeatForever(SKAction.animate(with: knightIdleFrames, timePerFrame: 0.1)))
}
func walkOrc() {
orc.run(SKAction.repeatForever(SKAction.animate(with: orcWalkingFrames,timePerFrame: 0.025)))
}
func moveOrcForward() {
orc.run(SKAction.repeatForever(SKAction.moveBy(x: 55, y: 0, duration: 0.25)))
}
func buildRandomOrcs () {
let wait = SKAction.wait(forDuration: TimeInterval(makeRandomNumberBetween(min: 0, max: 0)))
let spawn = SKAction.run {
self.buildOrc(yposition: self.makeRandomCGFloatNumber())
}
let spawning = SKAction.sequence([spawn,wait])
self.run(SKAction.repeat(spawning, count: 10))
}
func makeRandomCGFloatNumber() -> CGFloat {
let randomNumber = arc4random_uniform(UInt32((frame.maxY-orcWidth/2) - (frame.minY+orcWidth/2))) + UInt32(frame.minY+orcWidth/2)
return CGFloat(randomNumber)
}
func makeRandomNumberBetween (min: Int, max: Int) -> Int{
let randomNumber = arc4random_uniform(UInt32(max - min)) + UInt32(min)
return Int(randomNumber)
}
func didBegin(_ contact: SKPhysicsContact) {
let collision:UInt32 = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask
if collision == orcCategory | knightCategory {
self.scene?.view?.isPaused = true
print("COLLIDED")
}
}
}
The problem is that the scene pauses almost 2-3 seconds after the collision.
I changed the position of knight and delay time changed.
For example, if I set position to frame.minX+orcWidth/2 there is no delay.
What is wrong with my code?

Answer 1

Your problem isn't things are being delayed, your problem is your bounding box is not where you think it is
use view.showPhysics = true to determine where your boxes are
once you realize they are in the wrong spots, go to this line
knight.physicsBody = SKPhysicsBody(rectangleOf: knight.size, center: knight.position)
and fix it
knight.physicsBody = SKPhysicsBody(rectangleOf: knight.size)
Do so for the rest of your bodies

Answer 2

My guess is that manipulations of SKView properties must happen on main thread, i.e.
DispatchQueue.main.async { [unowned self] in
self.scene?.view?.isPaused = true
print("COLLIDED")
}