Sprite Kit - 节点离开屏幕的通知程序

Question

Sprite Kit中是否有事件/通知告诉我节点何时离开屏幕？ 让我们说当我离开屏幕底部时，我想要一个彩色圆圈出现在顶部。这意味着我需要知道它何时离开屏幕。

Answer 1

我认为你需要自己检查，

- (void)update:(NSTimeInterval)currentTime {

    if (node.position.y > screenHeight+nodeSize){ // need to define first, of course
          // do something like NSLog(); or [removeFromParent] or whatever =)
    }
}

Answer 2

精灵套件在精灵离开屏幕时不会生成通知。您需要添加自己的测试。这是一个例子......

- (void) update:(NSTimerInterval)currentTime
{
    CGPoint newPosition = CGPointMake(node.position.x, node.position.y);

    if (node.position.y > maxY+node.size.y/2) {
        newPosition.y = minY;
    }
    else if (node.position.y < minX-node.size.y/2) {
        newPosition.y = maxY;
    }

    if (node.position.x > maxX+node.size.x/2) {
        newPosition.x = minX;
    }
    else if (node.position.x < minX-node.size.x/2) {
        newPosition.x = maxX;
    }
    node.position = newPosition;