Swift: executing commands upon contact between nodes - swift

Question

Right now, I have a brick that falls down the screen. When it hits my square nothing happens. As you can see in the image below, I have four triangles that make up a square in the same spot, but with a low opacity. This is to help differentiate between what side of the square is contacted. However, nothing respawns or despawns win the brick hits the triange (the trianges that make up the square.)
Image of Game
func spawnBrick() {
let randomFunc = [self.spawnbrickTop, self.spawnbrickBottom, self.spawnbrickLeft, self.spawnbrickRight]
let randomResult = Int(arc4random_uniform(UInt32(randomFunc.count)))
randomFunc[randomResult]()
}
func spawnbrickTop() {
brickTop.size = CGSize(width: 210, height: 105)
brickTop.name = "BrickTop"
brickTop.position = CGPoint(x: frame.midX, y: frame.maxY)
brickTop.zPosition = 1.5
//physics stuff begins here
brickTop.physicsBody = SKPhysicsBody(circleOfRadius: max(brickTop.size.width / 2,
brickTop.size.height / 2))
brickTop.physicsBody?.categoryBitMask = PhysicsCategories.brickTopCategory
brickTop.physicsBody?.contactTestBitMask = PhysicsCategories.basicTopCategory |
PhysicsCategories.basicBottomCategory |
PhysicsCategories.basicLeftCategory |
PhysicsCategories.basicRightCategory
brickTop.physicsBody?.collisionBitMask = PhysicsCategories.none
//bye bye physics
self.addChild(brickTop)
}
func spawnbrickBottom() {
brickBottom.size = CGSize(width: 230, height: 101)
brickBottom.name = "BrickBottom"
brickBottom.position = CGPoint(x: frame.midX, y: frame.maxY)
brickBottom.zPosition = 1.5
//physics stuff begins here
brickBottom.physicsBody = SKPhysicsBody(circleOfRadius: max(brickBottom.size.width / 2,
brickBottom.size.height / 2))
brickBottom.physicsBody?.categoryBitMask = PhysicsCategories.brickBottomCategory
brickBottom.physicsBody?.contactTestBitMask = PhysicsCategories.basicTopCategory |
PhysicsCategories.basicBottomCategory |
PhysicsCategories.basicLeftCategory |
PhysicsCategories.basicRightCategory
brickBottom.physicsBody?.collisionBitMask = PhysicsCategories.none
//bye bye physics
self.addChild(brickBottom)
}
func spawnbrickLeft() {
brickLeft.size = CGSize(width: 170, height: 80)
brickLeft.name = "BrickLeft"
brickLeft.position = CGPoint(x: frame.midX, y: frame.maxY)
brickLeft.zPosition = 1.5
//physics stuff begins here
brickLeft.physicsBody = SKPhysicsBody(circleOfRadius: max(brickLeft.size.width / 2,
brickLeft.size.height / 2))
brickLeft.physicsBody?.categoryBitMask = PhysicsCategories.brickLeftCategory
brickLeft.physicsBody?.contactTestBitMask = PhysicsCategories.basicTopCategory |
PhysicsCategories.basicBottomCategory |
PhysicsCategories.basicLeftCategory |
PhysicsCategories.basicRightCategory
brickLeft.physicsBody?.collisionBitMask = PhysicsCategories.none
//bye bye physics
self.addChild(brickLeft)
}
func spawnbrickRight() {
brickRight.size = CGSize(width: 140, height: 95)
brickRight.name = "BrickRight"
brickRight.position = CGPoint(x: frame.midX, y: frame.maxY)
brickRight.zPosition = 1.5
//physics stuff begins here
brickRight.physicsBody = SKPhysicsBody(circleOfRadius: max(brickRight.size.width / 2,
brickRight.size.height / 2))
brickRight.physicsBody?.categoryBitMask = PhysicsCategories.brickRightCategory
brickRight.physicsBody?.contactTestBitMask = PhysicsCategories.basicTopCategory |
PhysicsCategories.basicBottomCategory |
PhysicsCategories.basicLeftCategory |
PhysicsCategories.basicRightCategory
brickRight.physicsBody?.collisionBitMask = PhysicsCategories.none
//bye bye physics
self.addChild(brickRight)
}
func spawnBasicBrick() {
basicBrick.size = CGSize(width: 200, height: 177.6)
basicBrick.position = CGPoint(x: frame.midX, y: frame.minY + basicBrick.size.width)
basicBrick.zPosition = 1
basicBrick.physicsBody = SKPhysicsBody(rectangleOf: basicBrick.size)
basicBrick.physicsBody?.categoryBitMask = PhysicsCategories.basicBrickCategory
basicBrick.physicsBody?.isDynamic = false
basicBrick.physicsBody?.allowsRotation = true
addChild(basicBrick)
}
func spawnBasicTop() {
basicTop.size = CGSize(width: 400, height: 400)
basicTop.position = CGPoint(x: 230, y: 200)
basicTop.zPosition = 1.5
basicTop.alpha = 0.3
basicTop.name = "BasicTop"
//physics stuff begins here
basicTop.physicsBody = SKPhysicsBody(rectangleOf: basicTop.size)
basicTop.physicsBody?.categoryBitMask = PhysicsCategories.basicTopCategory
basicTop.physicsBody?.isDynamic = false
basicTop.physicsBody?.allowsRotation = true
//bye bye physics
addChild(basicTop)
}
func spawnBasicBottom() {
basicBottom.size = CGSize(width: 400, height: 400)
basicBottom.position = CGPoint(x: 230, y: 200)
basicBottom.zPosition = 1.5
basicBottom.alpha = 0.3
basicBottom.name = "BasicBottom"
//physics stuff begins here
basicBottom.physicsBody = SKPhysicsBody(rectangleOf: basicBottom.size)
basicBottom.physicsBody?.categoryBitMask = PhysicsCategories.basicBottomCategory
basicBottom.physicsBody?.isDynamic = false
//bye bye physics
addChild(basicBottom)
}
func spawnBasicLeft() {
basicLeft.size = CGSize(width: 400, height: 400)
basicLeft.position = CGPoint(x: 230, y: 200)
basicLeft.zPosition = 1.5
basicLeft.alpha = 0.3
basicLeft.name = "BasicLeft"
//physics stuff begins here
basicLeft.physicsBody = SKPhysicsBody(rectangleOf: basicLeft.size)
basicLeft.physicsBody?.categoryBitMask = PhysicsCategories.basicLeftCategory
basicLeft.physicsBody?.isDynamic = false
//bye bye physics
addChild(basicLeft)
}
func spawnBasicRight() {
basicRight.size = CGSize(width: 400, height: 400)
basicRight.position = CGPoint(x: 230, y: 200)
basicRight.zPosition = 1.5
basicRight.alpha = 0.3
basicRight.name = "BasicRight"
//physics stuff begins here
basicRight.physicsBody = SKPhysicsBody(rectangleOf: basicRight.size)
basicRight.physicsBody?.categoryBitMask = PhysicsCategories.basicRightCategory
basicRight.physicsBody?.isDynamic = false
//bye bye physics
addChild(basicRight)
}
extension GameScene: SKPhysicsContactDelegate {
func didBegin(_ contact: SKPhysicsContact) {
//01
//10
//11
let contactMask = contact.bodyA.categoryBitMask |
contact.bodyB.categoryBitMask
if contactMask == PhysicsCategories.brickTopCategory |
(PhysicsCategories.basicTopCategory) {
if let brickTop = contact.bodyA.node?.name == "BrickTop" ? contact.bodyA.node
as? SKSpriteNode : contact.bodyB.node as? SKSpriteNode {
if contact.bodyA.node?.name == "BrickTop" &&
contact.bodyB.node?.name == "BasicTop" {
print("Correct!")
brickTop.run(SKAction.fadeOut(withDuration: 0.05), completion: {
self.brickTop.removeFromParent()
self.spawnBrick()
})
}
}
else if contactMask == PhysicsCategories.brickBottomCategory |
(PhysicsCategories.basicBottomCategory) {
if let brickBottom = contact.bodyA.node?.name == "BrickBottom" ? contact.bodyA.node
as? SKSpriteNode : contact.bodyB.node as? SKSpriteNode {
if contact.bodyA.node?.name == "BrickBottom" &&
contact.bodyB.node?.name == "BasicBottom" {
print("Correct!")
brickBottom.run(SKAction.fadeOut(withDuration: 0.05), completion: {
self.brickBottom.removeFromParent()
self.spawnBrick()
})
}
}
else if contactMask == PhysicsCategories.brickLeftCategory |
(PhysicsCategories.basicLeftCategory) {
if let brickLeft = contact.bodyA.node?.name == "BrickLeft" ? contact.bodyA.node
as? SKSpriteNode : contact.bodyB.node as? SKSpriteNode {
if contact.bodyA.node?.name == "BrickLeft" &&
contact.bodyB.node?.name == "BasicLeft" {
print("Correct!")
brickLeft.run(SKAction.fadeOut(withDuration: 0.05), completion: {
self.brickLeft.removeFromParent()
self.spawnBrick()
})
}
}
else if contactMask == PhysicsCategories.brickRightCategory |
(PhysicsCategories.basicRightCategory) {
if let brickRight = contact.bodyA.node?.name == "BrickRight" ? contact.bodyA.node
as? SKSpriteNode : contact.bodyB.node as? SKSpriteNode {
if contact.bodyA.node?.name == "BrickRight" &&
contact.bodyB.node?.name == "BasicRight" {
print("Correct!")
brickRight.run(SKAction.fadeOut(withDuration: 0.05), completion: {
self.brickRight.removeFromParent()
self.spawnBrick()
})
}
}
else {
gameOver()
}
}
}
}
}
}
}
enum PhysicsCategories {
static let none: UInt32 = 0
static let brickCategory: UInt32 = 1//01
static let brickTopCategory: UInt32 = 1 //01
static let brickBottomCategory: UInt32 = 1//01
static let brickLeftCategory: UInt32 = 1//01
static let brickRightCategory: UInt32 = 1//01
static let basicTopCategory: UInt32 = 1 //10; shifts all bits to the left
static let basicBottomCategory: UInt32 = 1 //10; shifts all bits to the left
static let basicLeftCategory: UInt32 = 1 //10; shifts all bits to the left
static let basicRightCategory: UInt32 = 1 //10; shifts all bits to the left
static let basicBrickCategory: UInt32 = 1
}

Answer 1

The problem is probably in lines like this:
brickTop.physicsBody?.contactTestBitMask = PhysicsCategories.basicTopCategory
brickTop.physicsBody?.contactTestBitMask = PhysicsCategories.basicBottomCategory
brickTop.physicsBody?.contactTestBitMask = PhysicsCategories.basicLeftCategory
brickTop.physicsBody?.contactTestBitMask = PhysicsCategories.basicRightCategory
In this code, the contact bitmask ends up just being basicRight. You want to combine them. This is assuming that you set up the categories correctly to begin with (as 1, 2, 4, 8, etc)
You want it more like this:
brickTop.physicsBody?.contactTestBitMask = PhysicsCategories.basicTopCategory |
PhysicsCategories.basicBottomCategory |
PhysicsCategories.basicLeftCategory |
PhysicsCategories.basicRightCategory
Here is how this is supposed to work
You have a bunch of nodes in your scene
You group them into categories that have similar behavior
You create a category enum/value for each category as a bit in a mask (1, 2, 4, etc), which is (0x1 << 0, 0x1 << 1, 0x1 << 2)
You put the nodes into categories (using | to combine the category values)
You set the contactTest and collisionDetect bit masks (using | to combine the category values)
I don't know how your game is supposed to work, but there are several things that feel weird about your code.
You use the same number for different categories
You don't combine them into bitmasks.
Imagine I have the game Pong. I want to detect when the ball hits
The sidewalls to bounce it
The top and bottom of the screen to record an out
The paddles to bounce it
Nodes
ball
left wall
right wall
bottom
top
top paddle
bottom paddle
player 1 score
player 2 score
Categories (this is just an example -- it's not the only way)
CategoryNone: 0
CategoryGamePiece: 1
CategoryOutDetector: 2
CategoryNonInteractive: 4 (use for the score nodes)
The ball bounces off the paddles and side walls. It also interacts with invisible out detectors on the top and bottom. It is in two categories (using |)
ball.categoryBitMask = CategoryGamePiece | CategoryOutDetector
ball.collisionBitMask = CategoryGamePiece
ball.contactTestBitMask = CategoryOutDetector
The paddle and side wall only interact with the ball as a game piece (colliding)
paddleTop.categoryBitMask = CategoryGamePiece
paddleTop.collisionBitMask = CategoryGamePiece
paddleTop.contactTestBitMask = CategoryNone
leftWall.categoryBitMask = CategoryGamePiece
leftWall.collisionBitMask = CategoryGamePiece
leftWall.contactTestBitMask = CategoryNone
The bottom only interacts with the ball as a contact test (doesn't change its motion)
bottomOut.categoryBitMask = CategoryOutDetector
bottomOut.collisionBitMask = CategoryNone
bottomOut.contactTestBitMask = CategoryOutDetector