将精灵附加到 SKPhysicsBody

Posted 2023-03-16

【中文标题】将精灵附加到 SKPhysicsBody

【英文标题】：getting the sprite attached to a SKPhysicsBody

【发布时间】：2017-10-21 20:50:52

【问题描述】：

我正在为一个精灵设置动画，当它接触另一个精灵时，会调用物理接触函数。比，在这个函数中，我试图让精灵与另一个接触。它的 body 是 bodyA 但它是一个 SKPhysicsBody，它不能转换为一个 SKSpriteNode。你有什么想法？ 该函数在接触时被正确调用，我只是尝试获取身体接触的精灵。最后的想法是让动作附加到我正在寻找的精灵上，但我想当你拥有精灵时它很容易。

    let shootCategory: UInt32 = 0x1 << 0
    let enemyCategory: UInt32 = 0x1 << 1


    // Declaration of the SKPhysicsBody of the sprite wich will touch the other one
    sprite.physicsBody = SKPhysicsBody(circleOfRadius: (20))
    sprite.physicsBody?.usesPreciseCollisionDetection = true
    sprite.physicsBody?.categoryBitMask = shootCategory
    sprite.physicsBody?.collisionBitMask = shootCategory | enemyCategory
    sprite.physicsBody?.contactTestBitMask = shootCategory | enemyCategory
    sprite.physicsBody?.affectedByGravity = false

    // Declaration of the SKPhysicsBody of the sprite wich will be touched
    sprite.run(SKAction.group([moveAction, fadeInAction]))
    sprite.physicsBody = SKPhysicsBody(circleOfRadius: (20))
    sprite.physicsBody?.usesPreciseCollisionDetection = true
    sprite.physicsBody?.categoryBitMask = enemyCategory
    sprite.physicsBody?.collisionBitMask = shootCategory | enemyCategory
    sprite.physicsBody?.contactTestBitMask = shootCategory | enemyCategory
    sprite.physicsBody?.affectedByGravity = false


    func didBegin(_ contact: SKPhysicsContact) 

    if (contact.bodyA.categoryBitMask == enemyCategory) && (contact.bodyB.categoryBitMask == shootCategory)

        // I tried this to get the sprite wich the bodyB is attached to but it doesn't even build
        let sprite: SKSpriteNode = sprite.contact.bodyB
        contact.bodyA.removeAction(forKey: "moveToAction")
    

【问题讨论】：

Apple 文档的存在是有原因的，我建议使用它们developer.apple.com/documentation/spritekit/skphysicsbody/…

【参考方案1】：

我终于发现解决方案真的很简单：

    let Node = contact.bodyB.node as! SKSpriteNode