所以我有一个shipNode(最初是面向右的)和两个子节点_laserCannon1(和2),它们是通过以下方法配置的:-(void)initializeLaserCannonLocations{CGSizesize=CGSizeMake(4.0,4.0);_laserCannon1=[SKSpriteNodespriteNodeWithColor:[SKColoryellowColor]size:size];_laserCannon2=[SKSpriteNodespriteNodeWithColor:[SKColoryellowColor]size:size];_laserCanno