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iOS

Posted by Dewan Payroda
Dewan Payroda
1,954 Points

SKPhysicsContact Not Detecting categoryBitMask Collision

So I have my "Floor.swift" class below which is basically a bunch of walls. I have objects coming from the top of the screen and once the Floor and SKSpriteNodes collide, I'd like the SKSpriteNode to be removed. Below is my Floor class.

import Foundation import SpriteKit

class Floor: SKNode {
    override init() {
        super.init()

        let leftWall = SKSpriteNode(color: UIColor.brown, size: CGSize(width: 5, height: 50))
        leftWall.position = CGPoint(x: 0, y: 50)
        leftWall.physicsBody = SKPhysicsBody(rectangleOf: leftWall.size)
        leftWall.physicsBody!.isDynamic = false
        self.addChild(leftWall)

        let rightWall = SKSpriteNode(color: UIColor.brown, size: CGSize(width: 5, height: 50))
        rightWall.position = CGPoint(x: 375, y: 50)
        rightWall.physicsBody = SKPhysicsBody(rectangleOf: rightWall.size)
        rightWall.physicsBody!.isDynamic = false
        self.addChild(rightWall)

        let bottomWall = SKSpriteNode(color: UIColor.brown, size: CGSize(width: 500, height: 10))
        bottomWall.position = CGPoint(x: 150, y: -5)
        bottomWall.physicsBody = SKPhysicsBody(rectangleOf: bottomWall.size)
        bottomWall.physicsBody!.isDynamic = false
        self.addChild(bottomWall)

        // Set the bit mask properties
        self.physicsBody?.categoryBitMask = floorCategory
        self.physicsBody?.contactTestBitMask = objectCategory | pointCategory | lifeCategory
        self.physicsBody?.collisionBitMask = dodgeCategory
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemted")
    }
}

Then in my GameScene class under "func didBegin(_ contact: SKPhysicsContact)" I wrote:

if (contact.bodyA.categoryBitMask == floorCategory) && (contact.bodyB.contactTestBitMask == objectCategory | pointCategory | lifeCategory) { contact.bodyB.node!.removeFromParent() print("COLLISION") }

But for some reason I'm not getting any detection what's so ever. I made my "Floor" class be a "contactTestBitMask" on each class of my objectCategory, pointCategory, lifeCategory. What am I doing wrong!? My other collisions are detected but not this one.I tried doing "let ourUnionOfBodies = SKPhysicsBody(bodies: [leftWall.physicsBody!, rightWall.physicsBody!, bottomWall.physicsBody!])" and following that I wrote on the next line "ourUnionOfBodies.isDynamic = false" but it still doesn't work? I don't see no collision detection they just fall right through.