Spritekit Detecting Sprite Overlap with Collisions off - ios

Question

Currently I have a Swift/Spritekit app that drops a sprite from the sky, they have collisions off so they can fall through the floor, however I am trying to make a statement that will detect when the player sprite touches the sprite falling from the sky then deletes that child and adds a point to the score var.
Update: 04/29/18 2:10 CST
As of now this is what I have
import SpriteKit
import GameplayKit
class GameScene: SKScene, SKPhysicsContactDelegate {
var activePlayer:SKSpriteNode! = SKSpriteNode() //Sets active character
var bg:SKSpriteNode! = SKSpriteNode()
var bananaCollected = 0 //Defines banana var
var timer: Timer?
let bananaCat : UInt32 = 0x1 << 1
let playerCat : UInt32 = 0x1 << 2
func bananaDrop() { //Defines bananaDrop
let banana = SKSpriteNode(imageNamed:"banana")
//print("- Debug: [bananaDrop] successfully initiated -")
banana.name = "banana"
//Size of banana
banana.xScale = 0.25
banana.yScale = 0.25
//Defines physics properties
let physicsBody = SKPhysicsBody(circleOfRadius: 15)
//let physicsBody = SKPhysicsBody()
//physicsBody.pinned = true //Suspend in air
physicsBody.allowsRotation = false
physicsBody.affectedByGravity = true
//physicsBody.collisionBitMask = 0
banana.physicsBody?.categoryBitMask = bananaCat
banana.physicsBody?.collisionBitMask = 0
banana.physicsBody?.contactTestBitMask = playerCat
//categoryBitMask is what the physics category of the object is
//banana.physicsBody!.categoryBitMask = playerCategory
//collisionBitMask is what the physics category of objects that this cannot pass through are...multiple categories would be typed like... `cat1 | cat2`
//banana.physicsBody!.collisionBitMask = 0
//contactTestBitMask is what the physics category of the objects that we get alerted to upon contact
//activePlayer.physicsBody!.contactTestBitMask = obstacleCategory
banana.physicsBody = physicsBody
//Starting Location Defined
var x: CGFloat = 0 //Defines X
let y: CGFloat = 400 //Defines how high up banana drops
let bananaDrop = GKShuffledDistribution(lowestValue: 1, highestValue: 11)
//Drop locations defined (relation to X)
switch bananaDrop.nextInt() {
case 1:
x = -170
case 2:
x = -160
case 3:
x = -120
case 4:
x = -80
case 5:
x = -40
case 6:
x = 0
case 7:
x = 40
case 8:
x = 80
case 9:
x = 120
case 10:
x = 160
case 11:
x = 170
default:
fatalError("Case num outside range")
}
banana.position = CGPoint(x: x, y: y)
//Adds banana
self.addChild(banana)
}
func bDropF() { //Defintes Banana Drop Final
Timer.scheduledTimer(withTimeInterval: 1, repeats: true, block: { [weak self] timer in
self?.timer = timer
self?.timerTime()
})
}
//Stop droping bananas
deinit {
self.timer?.invalidate()
}
func timerTime() {
bananaDrop()
}
override func didMove(to view: SKView) {
print("- Debug: Game Scene Loaded -")
bDropF() //Calls banana drop
if let setupBG:SKSpriteNode = self.childNode(withName: "bg") as? SKSpriteNode {
bg = setupBG
bg.name = "bg"
bg.physicsBody?.affectedByGravity = false
bg.zPosition = -1
}
func didBeginContact(_ contact: SKPhysicsContact){ //Banana Collect
if let firstNode = contact.bodyA.node as? SKSpriteNode, let secondNode = contact.bodyB.node as? SKSpriteNode {
let object1: String = firstNode.name!
let object2: String = secondNode.name!
if (object1 == "player") || (object2 == "banana") {
print("colliding!")
}
}
}
//Player Definitions
if let randoPlayer:SKSpriteNode = self.childNode(withName: "player") as? SKSpriteNode { //Test for Char type
activePlayer = randoPlayer //Char Set
activePlayer.physicsBody?.isDynamic = true //Set dynamic
activePlayer.physicsBody?.affectedByGravity = true //Set dynamic gravity
activePlayer.name = "player"
print("Player Initiated")
print("Physics set :: Dynamic(true):AffectedByGravity(true)")
} else {
print("Failed to initiate player")
}
}
func moveActivePlayerR() {//Right Touch Player Movements Defined
let walkAnimation:SKAction = SKAction(named: "WalkRight")!
let moveAction:SKAction = SKAction.moveBy(x: 100, y: 0, duration: 0.5) //Move Right Side
//let moveRight:SKAction = SKAction.group([walkAnimation, moveAction]) //Depricated
let sound = SKAction.playSoundFileNamed("walk.wav", waitForCompletion: false)
let finalWalkR:SKAction = SKAction.group([walkAnimation, moveAction, sound])
activePlayer.run(finalWalkR)
}
func moveActivePlayerL() { //Left Touch Player Movements Defined
let walkAnimation:SKAction = SKAction(named: "WalkLeft")!
let moveAction:SKAction = SKAction.moveBy(x: -100, y: 0, duration: 0.5) //Move Left Side
//let moveRight:SKAction = SKAction.group([walkAnimation, moveAction]) //Depricated
let sound = SKAction.playSoundFileNamed("walk.wav", waitForCompletion: false)
let finalWalkL:SKAction = SKAction.group([moveAction, sound, walkAnimation])
activePlayer.run(finalWalkL)
}
func touchDown(atPoint pos : CGPoint) {
print("touch \( pos.x),\(pos.y)") //Debug print
if(pos.x > 0) { //if touched right side of screen
print("Right touch")
moveActivePlayerR()
} else if (pos.x < 0) { //if touched left side of screen
print("Left touch")
moveActivePlayerL()
}
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
for t in touches {
self.touchDown(atPoint: t.location(in: self))
}
}
}
However even with these categories setup it still appears that I am unable to get them to collide properly. When they touch each other there is nothing in my console indicating that they have collided. Please help!

Answer 1

You do not have to have a collisionBitMask set in order to detect contact, you just need to set the contactTestBitMask to the category of the obstacle you want to detect the collision with. You then check for the collision in the didBegin func. Ensure that you have the SKPhysicsContactDelegate set on your scene.
class GameScene: SKScene, SKPhysicsContactDelegate
self.physicsWorld.contactDelegate = self
when setting up your objects
//categoryBitMask is what the physics category of the object is
object.physicsBody!.categoryBitMask = playerCategory
//collisionBitMask is what the physics category of objects that this cannot pass through are...multiple categories would be typed like... `cat1 | cat2`
object.physicsBody!.collisionBitMask = 0
//contactTestBitMask is what the physics category of the objects that we get alerted to upon contact
object.physicsBody!.contactTestBitMask = obstacleCategory
the didBegin func in your scene
func didBeginContact(_ contact: SKPhysicsContact) {
if let firstNode = contact.bodyA.node as? SKSpriteNode, let secondNode = contact.bodyB.node as? SKSpriteNode {
let object1: String = firstNode.name!
let object2: String = secondNode.name!
if (object1 == "obstacle") || (object2 == "obstacle") {
//run some code because these 2 have collided
}
}
}
...or...
func didBeginContact(_ contact: SKPhysicsContact) {
if contact.bodyA.categoryBitMask == PhysicsCategory.obstacleCategory || contact.bodyB.categoryBitMask == PhysicsCategory.obstacleCategory {
//obstacle has hit player do something
}
}