target/generated-sources/template/com/flowpowered/math/imaginary/Complexd.java
public static Complexd fromRotationTo(Vector2d from, Vector2d to) {
        return fromAngleRad(TrigMath.acos(from.dot(to) / (from.length() * to.length())));
    }
public static Complexd fromRotationTo(Vector2d from, Vector2d to) {
        return fromAngleRad(TrigMath.acos(from.dot(to) / (from.length() * to.length())));
    }
Creates a new complex from the angle defined from the first to the second vector.

@param from The first vector
@param to The second vector
@return The complex defined by the angle between the vectors