swift - didBeginContact 无法正常工作

Question

我为每个想要相互交互的不同对象创建了一个 struct PhysicsCatagory

struct PhysicsCatagory {
    static let Blade : UInt32 = 1
    static let Laser : UInt32 = 2

在我的类 GameScene 之上

 class GameScene: SKScene, SKPhysicsContactDelegate {

然后我在 didMoveToView 方法中用它的 physicsBody 初始化了一个 SKSpriteNode Blade

override func didMoveToView(view: SKView) {
    physicsWorld.contactDelegate = self
    Blade.position = CGPointMake(self.size.width / 2, (self.size.height / 14))
    Blade.anchorPoint = CGPointMake(0.5, -0.13)
    Blade.physicsBody = SKPhysicsBody(rectangleOfSize: Blade.size)
    Blade.physicsBody?.categoryBitMask = PhysicsCatagory.Blade
    Blade.physicsBody?.contactTestBitMask = PhysicsCatagory.Laser
    Blade.physicsBody?.dynamic = false

    self.addChild(Blade)
}

以及方法 shootLaser 中的 SKSpriteNode 激光及其物理体

func shootLaser(){
    var Laser = SKSpriteNode(imageNamed: "Laser.png")
    Laser.position = Enemy.position
    Laser.zPosition = -5
    Laser.physicsBody = SKPhysicsBody(rectangleOfSize: Laser.size)
    Laser.physicsBody?.categoryBitMask = PhysicsCatagory.Laser
    Laser.physicsBody?.contactTestBitMask = PhysicsCatagory.Blade
    Laser.physicsBody?.dynamic = false

    let action = SKAction.moveBy(laserVector, duration: 0.7)
    let actionDone = SKAction.removeFromParent()
    Laser.runAction(SKAction.sequence([action,actionDone]))
    self.addChild(Laser)
}

但是当他们在模拟中发生碰撞时，并没有调用didBeginContact方法，也没有打印“Hello”

func didBeginContact(contact: SKPhysicsContact) {
NSLog("Hello")
}

为什么在碰撞时不调用 didBeginContact 方法？提前致谢 (:

Answer 1

Sprite Kit 不会检查非动态物理体之间的接触，因为它们预计不会移动。如果您不希望您的 Sprite 由于重力而从屏幕上掉下来，请将物理体的 affectedByGravity 属性设置为 false 并设置 dynamic = true.