Question

我正在构建一个SpriteKit游戏，我正在从多维数组中加载一个级别。 loadlevel函数第一次工作。如果我在println分配之上physicsBody进行physicsBody（在physicBody初始化之后），则会失败。当我使用removeChildrenInArray删除所有图块时，我第二次运行加载级别时会抛出错误fatal error: unexpectedly found nil while unwrapping an Optional并且它指向下方println下方的行。而println表示physicsBody是nil。在我看来，没有理由重新初始化PhysicsBody应该是nil。 println打印physicsBody nil。我不知道为什么physicsBody会nil。我只是试图通过删除所有块节点并根据级别图在原始位置添加新节点来重置级别。

func loadLevel() {
    var levels = Levels().data
    var frameSize = view.frame.size
    var thisLevel = levels[currentLevel]
    println("running load level")
    for (rowIndex,row) in enumerate(thisLevel) {
        for (colIndex,col) in enumerate(row) {
            if col == 4 {
                continue
            }
            println("COL: \(col)")
            var tile = SKSpriteNode(texture: SKTexture(imageNamed: "brick_\(tileMap[col])"))
            tile.name = "tile_\(rowIndex)_\(colIndex)"
            tile.position.y = frameSize.height - (tile.size.height * CGFloat(rowIndex)) - (tile.size.height/2)
            tile.position.x = tile.size.width  * CGFloat(colIndex) + (tile.size.width/2)
            var physicsBody = SKPhysicsBody(rectangleOfSize: tile.size)
            tile.physicsBody = physicsBody
            tile.physicsBody.affectedByGravity = false
            tile.physicsBody.categoryBitMask = ColliderType.Block.toRaw()
            tile.physicsBody.contactTestBitMask = ColliderType.Ball.toRaw()
            tile.physicsBody.collisionBitMask = ColliderType.Ball.toRaw()
            scene.addChild(tile)
            tileCount++
        }
    }
}

这是我的ColliderType

enum ColliderType:UInt32 {
    case Paddle = 1
    case Block = 2
    case Wall = 3
    case Ball = 4
}

这是我的重置功能内容：

func reset() {
    tileCount = 0
    var removeTiles = [SKSpriteNode]()
    // remove all the tiles
    for child in scene.children {
        var a_tile = child as SKSpriteNode
        if a_tile.name.hasPrefix("tile_") {
            a_tile.removeFromParent()
            a_tile.name = ""
            removeTiles.append(a_tile)
        }
    }
    removeTiles.removeAll(keepCapacity: false)
    ball!.position = CGPoint(x: 200, y: 200)
    ballVel = CGPoint(x: 0, y: -5)
    currentLevel++
    loadLevel()
    lost = false
    won = false
}

这是我的Level结构

struct Tile {
    let map = ["blue","green","purple","red"]
}

struct Levels {
    let data = [
        [
            [4,4,0,4,0,4,0,4,0,4,0,4,0,0,4,4],
            [4,4,1,4,1,4,1,4,1,4,1,4,1,1,4,4],
            [4,4,2,4,2,4,2,4,2,4,2,4,2,2,4,4],
            [4,4,3,4,3,4,3,4,3,4,3,4,3,3,4,4]
        ],
        [
            [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
            [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1],
            [2,2,2,2,2,2,2,4,2,2,2,2,2,2,2,2],
            [3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3]
        ]
    ]
}

如果这是Swift中的一个错误，我试图找到解决方法，这样我就可以完成这项工作。

Answer 1

看起来SKPhysicsBody实例化为空大小。尝试使用显式大小创建物理主体对象，如下所示：

var physicsBody = SKPhysicsBody(rectangleOfSize: CGSizeMake(100, 100))

或者，您可以直接在SKSpriteNode上设置大小，或者使用其构造函数之一，这些构造函数采用CGSize构造，如initWithTexture:color:size:

使用SpriteKit和Swift，PhysicsBody是零

1 个答案: