Ios 无法创建物理体-Swift

我有一个名为ChainsawMaker.Swift的Swift文件，我想用它在整个游戏中创建链锯。当我调用此实例并将其添加到我的游戏中时，链锯和它的物理体将完美地添加到游戏中-除了控制台中弹出的错误：“物理体：无法创建物理体”。以下是ChainsawMaker.swift的代码：

import SpriteKit

class ChainsawMaker: SKSpriteNode {

func longChainsawCreator2 () -> SKSpriteNode {

    //LONG CHAINSAW
    let longChainsawWidth = size.width/3
    let longChainsawHeight = size.height*0.20

    let chainsaw = SKSpriteNode ()


    chainsaw.zPosition = 13
    chainsaw.anchorPoint = CGPoint(x: 0.5, y: 0.5)
    chainsaw.size = CGSize(width: longChainsawWidth, height: longChainsawHeight)
    let textures = [SKTexture(imageNamed: "chainsaw1"), SKTexture(imageNamed: "chainsaw2")]
    let animation = SKAction.animateWithTextures(textures, timePerFrame: 0.1)
    let runSawAnimation = SKAction.repeatActionForever(animation)
    chainsaw.runAction(runSawAnimation)




    var offsetX = chainsaw.frame.size.width/2;
    var offsetY = chainsaw.frame.size.height/2 + chainsaw.size.height/13;

    var path = CGPathCreateMutable();


    CGPathMoveToPoint(path, nil, chainsaw.frame.size.width/2 - offsetX, chainsaw.frame.size.height - offsetY);
    CGPathAddLineToPoint(path, nil, 0 + chainsaw.frame.size.width/12 - offsetX, chainsaw.frame.size.height - offsetY);
    CGPathAddLineToPoint(path, nil, 0 - offsetX, chainsaw.frame.size.height - chainsaw.size.height/2 - offsetY);
    CGPathAddLineToPoint(path, nil, 0 + chainsaw.size.width/28 - offsetX, chainsaw.frame.size.height - chainsaw.size.height/2 - chainsaw.size.height/6 - offsetY);

    CGPathAddLineToPoint(path, nil, 0 + chainsaw.frame.size.width/12 - offsetX, 0 + chainsaw.size.height/8 - offsetY);
    CGPathAddLineToPoint(path, nil, chainsaw.size.width - chainsaw.frame.size.width/12 - offsetX, 0 + chainsaw.size.height/8 - offsetY);

    CGPathAddLineToPoint(path, nil, chainsaw.size.width - offsetX, chainsaw.frame.size.height - chainsaw.size.height/2 - offsetY);

    CGPathAddLineToPoint(path, nil, chainsaw.size.width - chainsaw.frame.size.width/16 - offsetX, chainsaw.size.height - offsetY);


    CGPathCloseSubpath(path);

    chainsaw.physicsBody = SKPhysicsBody(polygonFromPath: path)


    chainsaw.physicsBody?.dynamic = true
    chainsaw.physicsBody?.categoryBitMask = chainsawCategory
    chainsaw.physicsBody?.contactTestBitMask = boCategory
    chainsaw.physicsBody?.collisionBitMask = noneCategory

    return chainsaw
}

}

这就是我如何在GamePlaySecene.swift中创建链锯实例的方法：

import SpriteKit

class GameScene: SKScene, SKPhysicsContactDelegate {
    var longChainsaw = ChainsawMaker()

    override func didMoveToView(view: SKView) {
     longChainsaw.longChainsawCreator2()
    longChainsaw.position = CGPoint(x: chainsawHolder.size.width/2, y:   chainsawHolder.size.height/2 - boHeight/2)

---

验证路径是否符合文档中所述的标准：“具有逆时针缠绕且无自相交的凸多边形路径。”确实如此。当我运行游戏时，它甚至正确地显示出来。当我把代码放在我的游戏场景中时，它也工作得很好。你试过看吗？