在SpriteKit游戏中使无限障碍向左移动

Question

我有一个可以投掷和拖动的SpriteKit游戏。当它被抛出时，SKCamera会跟随它。我想要的如下图所示：

我怎样才能构建这种障碍？

Answer 1

一种方法可能是您创建了一个添加SKShapeNode的功能，这是您的障碍。您可以使用阵列保留障碍物列表，其中您可以追踪所有障碍物，并在每次从视野中消失时移除第一个障碍物。这样你的节点数就会保持很低，你可以有无数的障碍。

这是一个示例代码，当玩家在游戏世界中传递最右边的障碍时会产生新的障碍。

private var obstacles = [SKShapeNode]()

private func addObstacle() {
    // Create obstacle aka SKShapeNode
    let obstacle = SKShapeNode(rectOf: CGSize(width: 50, height: 50))
    obstacle.fillColor = SKColor.white

    // If this is first obstacle, position it just beyond right side of the view. If not, get rightmost obstacles position and make a little gap between it and new obstacle.
    if let lastObstacle = self.obstacles.last {
        obstacle.position = CGPoint(x: lastObstacle.frame.maxX + self.frame.width/2, y: 0)
    } else {
        obstacle.position = CGPoint(x: self.frame.width/2 + obstacle.frame.width, y: 0)
    }

    // SKShapeNode have physicsbody where you can define categorybitmask etc
    obstacle.physicsBody?.categoryBitMask = ...

    // Add obstacle to the scene
    self.addChild(obstacle)

    // Add obstacle to array so we can keep record of those
    self.obstacles.append(obstacle)
}

override func update(_ currentTime: TimeInterval) {
    // If the rightmost obstacle come visible, create new obstacle
    if let lastObstacle = self.obstacles.last {
        if lastObstacle.frame.minX < self.camera.frame.maxX {
            self.addObstacle()
        }
    }

    // If arrays first obstacle is out of view, remove it from view and array
    if (self.obstacles.first?.frame.maxX ?? 0) < self.camera.frame.minX {
        self.obstacles.first?.removeFromParent()
        self.obstacles.removeFirst()
    }
}