我可以看到屏幕上显示的节点计数器：它不会随着岩石的数量增加
。

I can see that with the nodes counter shown on the screen : it doesn't increase with the number of rocks.

这是因为Sprite Kit默认只计算渲染节点（即屏幕上的节点）。要查看已淘汰的节点，您必须启用其他未记录的调试标志：

This is because Sprite Kit counts only "rendered" nodes (ie nodes on screen) by default. To see culled nodes, you have to enable an additional, undocumented debug flag:

[self.scene.view setValue:@(YES) forKey:@"_showsCulledNodesInNodeCount"];

或者，要获取节点的真实节点数，例如场景，请在此处添加想要记录节点数：

Alternatively, to get the true node count of a node, such as the scene, add this where you want to log the node count:

NSLog(@"node count: %u", (unsigned int)self.children.count);

换句话说：如果你没有从父节点中删除节点，Sprite Kit将不在任何情况下都不会自动执行此操作。但是，如果没有任何保留周期（通常在自定义SKNode子类中保存对父节点或兄弟节点的强引用时找到），它将在呈现新场景时清除旧场景的节点图。

In other words: if you don't remove a node from its parent, Sprite Kit will not do this for automatically under no circumstances. It will however clear up the node graph of the old scene when presenting a new scene, provided there aren't any retain cycles (commonly found when holding a strong reference to a parent or sibling node in a custom SKNode subclass).