ios - SKAction scaleBy : duration: SpriteKit

Question

我在尝试使用 [SKAction scaleBy: duration:]

使一个圆圈变大和变小时遇到了麻烦

SKAction *scaleDown = [SKAction scaleBy:0.2 duration:1.8];  
SKAction *scaleUp= [scaleDown reversedAction];
SKAction *fullScale = [SKAction sequence:@[scaleDown, scaleUp, scaleDown, scaleUp]];
[_circleChanging runAction:fullScale];

我得到的是圆圈变得如此之小，以至于消失了，然后就再也没有回来。它必须变小，然后恢复到原来的大小，重复 2 次。

Answer 1

尝试:

  SKAction *scaleDown = [SKAction scaleTo:0.2 duration:0.75];
       SKAction *scaleUp= [SKAction scaleTo:1.0 duration:0.75];
       SKAction *fullScale = [SKAction repeatActionForever:[SKAction sequence:@[scaleDown, scaleUp, scaleDown, scaleUp]]];
       [_circleChanging runAction:fullScale];