角度和弧度的转换

常用到如image1.transform = CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(335));

CGAffineTransformMakeRotation中要填的是弧度，所以要转换一下。

下面是两个宏，来实现互转

1。弧度转角度
#define RADIANS_TO_DEGREES(radians) ((radians) * (180.0 / M_PI))

NSLog(@”Output radians as degrees: %f”, RADIANS_TO_DEGREES(0.785398));

 

2。角度转弧度
// Degrees to radians
#define DEGREES_TO_RADIANS(angle) ((angle) / 180.0 * M_PI)

NSLog(@”Output degrees as radians: %f”, DEGREES_TO_RADIANS(45));
M_PI 定义在Math.h内，其值为3.14159265358979323846264338327950288