Vector2Angle returns degrees instead of radians, but all other raymath

[schveiguy]

functions use radians, making this awkward to use.

Per discussion on discord, raymath should always use radians. I found this one was left out by searching for 180 and 360.

[raysan5]

@schveiguy Good catch! I missed that one. Actually, there is an open issue that could be related: #2172

[schveiguy]

Actually, there is an open issue that could be related

that doesn't look like they were expecting radians, just like it returns 90° when it should return 0°

Changing that to the equivalent radians will not solve that problem. It seems like the math might be wrong?

[jdeokkim]

@raysan5 I believe atan2f(v2.y, v2.x) - atan2f(v1.y, v1.x) is the correct way to retrieve an angle between two vectors, based on the defintion of the arc tangent. Here's an article about it from Stack Overflow: https://stackoverflow.com/questions/21483999/using-atan2-to-find-angle-between-two-vectors/21486462