ios - 如何控制多个同名的 Sprite 套件节点？

Question

swift 2 SpriteKit

所以我使用以下代码随机生成敌人，然后将它们移向玩家。但由于某种原因，只有第一个敌人向玩家移动，其余的敌人什么也不做。我是新手，因此所有详细信息都会有所帮助。

在 didmovetoview 下:

        let wait = SKAction.waitForDuration(3, withRange: 2)
        let spawn = SKAction.runBlock {
            let Enemy = SKSpriteNode(imageNamed: "Enemy.png")
            Enemy.size.height = (70) //138
            Enemy.size.width = (49) //99
            Enemy.position = CGPointMake(CGRectGetWidth(self.frame) - 100 , CGRectGetHeight(self.frame) - 100)
            Enemy.physicsBody = SKPhysicsBody (rectangleOfSize: Enemy.size)
            Enemy.physicsBody!.dynamic = true
            Enemy.physicsBody!.allowsRotation = false
            Enemy.physicsBody!.friction = 0
            Enemy.physicsBody!.restitution = 0
            Enemy.physicsBody!.linearDamping = 1
            Enemy.physicsBody!.angularDamping = 1
            Enemy.name = "Enemy"
            Enemy.zPosition = 3
            self.addChild(Enemy)
            self.EnemyExists=true

        }
        let sequence = SKAction.sequence([wait, spawn])
        self.runAction(SKAction.repeatActionForever(sequence))

在更新功能下:

            let Enemy = childNodeWithName("Enemy") as! SKSpriteNode
            let Player = childNodeWithName("Player") as! SKSpriteNode

            if EnemySpeed == OriginalEnemySpeed {

                let impulseVector = CGVector(dx: (Player.position.x - Enemy.position.x)/200, dy: (Player.position.y - Enemy.position.y)/200)
                Enemy.physicsBody?.applyImpulse(impulseVector)
            }

            if Enemy.position.x + Enemy.size.width / 4 > size.width {
                Enemy.position.x = Enemy.size.width / 4

            }
            else if Enemy.position.x + Enemy.size.width / 4 < 0 {
                Enemy.position.x = size.width - Enemy.size.width / 4

            }

            if Enemy.position.y + Enemy.size.height / 4 > size.height {
                Enemy.position.y = Enemy.size.height / 4

            }
            else if Enemy.position.y + Enemy.size.height / 4 < 0 {
                Enemy.position.y = size.height - Enemy.size.height / 4

            }

            EnemySpeed-=1
            if EnemySpeed < 1 {
                EnemySpeed = OriginalEnemySpeed
            }

Answer 1

childNodeWithName("Enemy") 只会拾取场景中名为 Enemy 的第一个 Sprite 。

您需要使用enumerateChildNodesWithName循环遍历所有名为敌人的 Sprite :

        enumerateChildNodesWithName("Enemy") {
            node, stop in
            let Enemy = node as! SKSpriteNode

            // Your enemy movement/update code here

        }

如果您的 EnemySpeed 变量应该指的是您当前正在处理的 Sprite 的速度，则您必须对它进行一些操作，因为它只是一个实例变量，而不是该变量的属性 Sprite 。您可能需要使用 Enemy.physicalsBody.velocity，它是一个 CGVector，因此要将其转换为您需要的速度:

enemySpeedX = enemy.physicsbody.velocity.dx
enemySpeedY = enemy.physicsbody.velocity.dy
enemySpeed = sqrt(enemySpeedX* enemySpeedX + enemySpeedY* enemySpeedY)

还要检查您的命名标准；大多数东西应该是驼峰式的，所以 Enemy 应该是 enemy，OriginalEnemySpeed 应该是 originalEnemySpeed 等等。