#include "geometry.h"

Vector3 calculate_normal(const Vector3& v1, const Vector3& v2, const Vector3& v3)
{
	Vector3 normal;
	const Vector3 U = v2 - v1;
	const Vector3 V = v3 - v1;

	normal.x = U.y * V.z - U.z * V.y;
	normal.y = U.z * V.x - U.x * V.z;
	normal.z = U.x * V.y - U.y * V.x;

	return normal.normalize();
}

const float random(const float& rangeMin, const float& rangeMax)
{
	const float range = rangeMax - rangeMin;
	return rangeMin + (float(rand())/float(RAND_MAX))*range;
}

const float random_int(const int& rangeMin, const int& rangeMax)
{
	const int range = rangeMax - rangeMin;
	return rangeMin + (rand() % range);
}