I suggest that you follow Sprite Kit’s coordinate and rotation conventions. Specifically, your sprite image should be facing right at zero degrees (the default value), and a positive value is a counter-clockwise rotation. That said, here's one way to apply an impulse in the direction a sprite is facing:

// Specify the force to apply to the SKPhysicsBody

#define ARC4RANDOM_MAX 0x100000000

Your code means this:

上传快照的时候提示“无法载入文件，请再试一次”，图片尺寸和格式都是没有问题的

A:文件名或路径中含有中文 

主要操作：(用來io7以下)

1. 视图1（ViewController1）中添加以下代码

There are two seemingly similar functions that take a parameter kSystemSoundID_Vibrate:

1)AudioServicesPlayAlertSound(kSystemSoundID_Vibrate);2)AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);

Both the functions vibrate the iPhone. But when you use the first function on devices that don’t support vibration, it plays a beep sound. The second function on the other hand does nothing on unsupported devices. So if you are going to vibrate the device continuously, as a alert, common sense says, use function 2.

[UIView animateWithDuration:0.5
                          delay:1.0
                        options: UIViewAnimationCurveEaseOut
                     animations:^{
                         self.basketTop.frame = basketTopFrame;
                         self.basketBottom.frame = basketBottomFrame;
                     } 
                     completion:^(BOOL finished){
                         NSLog(@"Done!");
                     }];

http://0922267152.blogspot.tw/2011/04/blog-post_13.html

來源：http://blog.csdn.net/baidu_21172753/article/details/42678487