Question

I’m trying to calculate the angular direction of a projectile, knowing it’s X and Y velocity I can find the magnitude of its movement, but I’m having a hard time wrapping my mind around getting the angular direction (in radians) that it is moving…

I assume there is a tan or a sin involved, but I’m a bit clueless otherwise…

Answer 1

You might be interested in Math.atan2.

Given an x and y around the origin, it will return the angle. E.g.

Math.atan2(  0,   1) === 0;
Math.atan2(0.5, 0.5) === Math.PI / 4;

It does take the direction into account, so you don’t have to worry about 1 / 1 or -1 / -1 (which would normally result in the same angle).