How to map atan2() to degrees 0-360
atan2, math, quartz-2d
Solution
(x > 0 ? x : (2*PI + x)) * 360 / (2*PI)
Problem
`atan2(y, x)` has that discontinuity at 180° where it switches to -180°..0° going clockwise. How do I map the range of values to 0°..360°? here is my code: ``` CGSize deltaPoint = CGSizeMake(endPoint.x - startPoint.x, endPoint.y - startPoint.y); float swipeBearing = atan2f(deltaPoint.height, deltaPoint.width); ``` I'm calculating the direction of a swiping touch event given the `startPoint` and `endPoint`, both XY point structs. The code is for the iPhone but any language that supports `atan2f()` will do.