swift - 碰撞后翻转 SKSpriteNode 纹理使其循环

Question

我正在学习一些 SpriteKit。我正在尝试这样做:点击向右移动节点 --> 在右墙上碰撞翻转节点的纹理 --> 改变方向并在左墙上重复。

问题是碰撞后它会循环图像翻转。什么可能导致这种情况？

我在触摸时移动 SKSPriteNode:

 moveAction = SKAction.moveBy(x: 100, y: 0, duration: 1)
 node.run(moveAction, withKey: "Right")
 node.physicsBody?.velocity = CGVector(dx: 0, dy: 0)
 node.physicsBody?.applyImpulse(CGVector(dx: 40, dy: 130))

这是我检测碰撞的方式:

if (firstBody.categoryBitMask & PhysicsCatagory.node == PhysicsCatagory.node &&
            secondBody.categoryBitMask & PhysicsCatagory.RightWall == PhysicsCatagory.RightWall) {

            direction = "Left"
            rotate()
        }else if (firstBody.categoryBitMask & PhysicsCatagory.RightWall == PhysicsCatagory.RightWall &&
            secondBody.categoryBitMask & PhysicsCatagory.node == PhysicsCatagory.node) {

            direction = "Left"
            rotate()
        }

像这样翻转节点:

func rotate(){
        if direction == "Right"{
            node.xScale = node.xScale * -1
            updateScoreAndChangeBackgroundColor()
        }else{
            node.xScale = node.xScale * -1
            updateScoreAndChangeBackgroundColor()
        }
    }

我知道只要方向没有改变，它就会一直发生碰撞，而我是在点击时发生碰撞的。但是我应该如何以及应该将节点弹回以防止这种情况发生？

Answer 1

试试这个...

func rotate(newDirection:String) {
    if newDirection != direction {
        node.xScale = node.xScale * -1
        updateScoreAndChangeBackgroundColor()
        direction = newDirection
    }
}

调用轮换

rotate (newDirection: "Left")

或者这个

rotate (newDirection: "Right")