選擇數組中的任何元素

Question

我正在開發一款遊戲，它包含在場景中移動的幾個箭頭。我已經設定了一些碰撞，我需要移除與障礙物相遇的箭頭。我設置的非常簡單而且功能強大，但只有一個箭頭，因爲它是數組的元素[0]，顯然如果另一個（不是[0]）觸及屏障，它將不會從父級移除。儘管需要爲每個數字手動賦值數組元素，有什麼辦法可以將碰撞委託給所有元素嗎？

// 3. react to the contact between the two nodes 
     if firstBody.categoryBitMask == barrier?.physicsBody?.categoryBitMask && 
      secondBody.categoryBitMask == arrows[0].physicsBody?.categoryBitMask { 
       // Player & barrier 

       gameOver(false) 
     } else if firstBody.categoryBitMask == goal?.physicsBody?.categoryBitMask && secondBody.categoryBitMask == arrows[0].physicsBody?.categoryBitMask { 
      // Player & Goal 

      arrows[0].removeFromParent() 
//   gameOver(true) 

謝謝！

:)

Answer 1

然後你初始化arrow和goal你應該給他們categoryBitMask小號

arrow.physicsBody?.categoryBitMask = 0x1 << 0 
goal.physicsBody?.categoryBitMask = 0x1 << 1 
barrie.physicsBody?.categoryBitMask = 0x1 << 2 

此外，我建議你創建Constants.swift文件和存儲您的常量存在。 Constants.swift：

let kCategoryArrow: UInt32 = 0x1 << 0 
let kCategoryGoal: UInt32 = 0x1 << 1 
let kCategoryBarrie: UInt32 = 0x1 << 2 

然後你就可以給categoryBitMask就像這樣（那麼你對它們進行初始化）

arrow.physicsBody?.categoryBitMask = kCategoryArrow 
goal.physicsBody?.categoryBitMask = kCategoryGoal 
barrier.physicsBody?.categoryBitMask = kCategoryBarrier 

而最後一件事接觸檢查：

/* Arrow vs Barrier */ 

    if bodyA.physicsBody?.categoryBitMask == kCategoryArrow && bodyB.physicsBody?.categoryBitMask == kCategoryBarrier { 
     gameOver(false) 
    } else if bodyA.physicsBody?.categoryBitMask == kCategoryBarrier && bodyB.physicsBody?.categoryBitMask == kCategoryBullet { 
     gameOver(false) 
    } 

    /* Arrow vs Goal */ 

    if bodyA.physicsBody?.categoryBitMask == kCategoryArrow && bodyB.physicsBody?.categoryBitMask == kCategoryGoal { 
     bodyA.node.removeFromParent() 
    } else if bodyA.physicsBody?.categoryBitMask == kCategoryGoal && bodyB.physicsBody?.categoryBitMask == kCategoryBullet { 
     bodyB.node.removeFromParent() 
    }