class ONB {

public:

	ONB(float3 normal);
	float3 WorldToLocal(const float3 &v);
	float3 LocalToWorld(const float3 &v);

private:

	float3 n;
	float3 s;
	float3 t;


};


ONB::ONB(float3 normal)
	: n(normal) {

	if (fabs(n.x) > fabs(n.z)) {
		s.x = -n.y;
		s.y = n.x;
		s.z = 0;
	} else {

		s.x = 0;
		s.y = -n.z;
		s.z = n.y;
	}

	s = normalize(s);
	t = cross(n, s);

}


float3 ONB::WorldToLocal(const float3 &v) {

	return make_float3(dot(v, s), dot(v, t), dot(v, n));

}


float3 ONB::LocalToWorld(const float3 &v) {

	return  (v.x * s) + (v.y * t) + (v.z * n);


}