如何避免这种程度的弧度误差？

Question

在使用核心图创建饼图时,我为给定代码添加了动画

    CABasicAnimation *rotation = [CABasicAnimation animationWithKeyPath:@"transform"];
   CATransform3D transform = CATransform3DMakeRotation(DegreesToRadians(360), 0, 0, 1);
   rotation.toValue = [NSValue valueWithCATransform3D:transform];  
    rotation.duration = 10.0f;
    [pieChart addAnimation:rotation forKey:@"rotation"];    

此代码提供以下错误语义问题:

Implicit declaration of function 'DegreesToRadians' is invalid in C99

我能做些什么来避免这种情况？

并且运行时它会产生以下错误:

Apple_o  Linker id error  "_DegreesToRadians", referenced from:

感谢致敬

维贾雅库马尔

Rhytha的iOS开发人员

https://rhytha.com/

Answer 1

只需定义一个宏,如:

#define DEGREES_RADIANS(angle) ((angle) / 180.0 * M_PI)

并改变你的方法,如:

CATransform3D transform = CATransform3DMakeRotation(DEGREES_RADIANS(360), 0, 0, 1);