Remove Gravity From SKNode Floor Class

Question

I've got two rectangles that show up in the beginning of my game but once it starts, gravity takes them down. I've got the code below in a separate "Floor.swift" class. I also have a "BitMaskCategories.swift" file with the info below.

let ballCategory : UInt32 = 0x1 << 1
let avoidCategory : UInt32 = 0x1 << 2
let floorCategory : UInt32 = 0x1 << 3
let pointCategory : UInt32 = 0x1 << 4
let lifeCategory : UInt32 = 0x1 << 5

And here is my "Floor.swift" class

import Foundation
import SpriteKit

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

        let leftWall = SKSpriteNode(color: UIColor.brown, size: CGSize(width: 50, height: 300))
        leftWall.position = CGPoint(x: 0, y: 100)
        leftWall.physicsBody!.isDynamic = false
        leftWall.physicsBody = SKPhysicsBody(rectangleOf: leftWall.size)
        self.addChild(leftWall)

        let rightWall = SKSpriteNode(color: UIColor.brown, size: CGSize(width: 50, height: 300))
        rightWall.position = CGPoint(x: 100, y: 200)
       rightWall.physicsBody!.isDynamic = false
        rightWall.physicsBody = SKPhysicsBody(rectangleOf: rightWall.size)
        self.addChild(rightWall)

        // self.physicsBody?.affectedByGravity = false
        // self.physicsBody?.isDynamic = false

        // Set the bit mask properties
        self.physicsBody?.categoryBitMask = balloonCategory
        self.physicsBody?.contactTestBitMask = nailDropCategory | pointCategory | lifeCategory
        //self.physicsBody?.collisionBitMask = balloonCategory
    }

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

Why do I get the error, "Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value" but when I use a "?" instead of "!" the app works but the rectangles fall. I need that line in order for them not to do that and I don't even get how this makes sense.

mugx · Accepted Answer · 2018-01-23T23:41:02.713

3

You are trying to assign: .isDynamic = false before the object initialization,

you should move leftWall.physicsBody!.isDynamic = false

after leftWall.physicsBody = SKPhysicsBody(rectangleOf: leftWall.size)

and the same for: rightWall.physicsBody!.isDynamic = false, move it

after: rightWall.physicsBody = SKPhysicsBody(rectangleOf: rightWall.size)

so your code might be:

let leftWall = SKSpriteNode(color: UIColor.brown, size: CGSize(width: 50, height: 300))
leftWall.position = CGPoint(x: 0, y: 100)
leftWall.physicsBody = SKPhysicsBody(rectangleOf: leftWall.size)
leftWall.physicsBody!.isDynamic = false
self.addChild(leftWall)

let rightWall = SKSpriteNode(color: UIColor.brown, size: CGSize(width: 50, height: 300))
rightWall.position = CGPoint(x: 100, y: 200)
rightWall.physicsBody = SKPhysicsBody(rectangleOf: rightWall.size)
rightWall.physicsBody!.isDynamic = false
self.addChild(rightWall)

edited Jan 23 '18 at 23:41

answered Dec 22 '17 at 00:45

mugx

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I appreciate you so freaking much! – Dewan Dec 22 '17 at 00:49
Glad you found it useful. Yeah! :) – mugx Dec 22 '17 at 00:50
So one thing led to another problem, I feel like you'll know the solution fairly fast. Check out my new post if you get a chance https://stackoverflow.com/questions/47946410/skphysicscontact-not-detecting-categorybitmask-collision – Dewan Dec 22 '17 at 19:37

Remove Gravity From SKNode Floor Class

1 Answers1