#include "Vectors.h"

void AddVector(Vector * v1, Vector * v2, Vector * v3)
{
	v3->x = v1->x + v2->x;
	v3->y = v1->y + v2->y;
	v3->z = v1->z + v2->z;
}

void SubtractVector(Vector * v1, Vector * v2, Vector * v3)
{
	v3->x = v1->x - v2->x;
	v3->y = v1->y - v2->y;
	v3->z = v1->z - v2->z;
}

void MultiplyVector(Vector * v1, Vector * v2, Vector * v3)
{
	v3->x = v1->x * v2->x;
	v3->y = v1->y * v2->y;
	v3->z = v1->z * v2->z;
}

void DivideVector(Vector * v1, Vector * v2, Vector * v3)
{
	v3->x = v1->x / v2->x;
	v3->y = v1->y / v2->y;
	v3->z = v1->z / v2->z;
}

void NormalizeVector(Vector * v)
{
	float Mag = VectorMagnitude(v);
	if (Mag != 0.0) {
		v->x /= Mag;
		v->y /= Mag;
		v->z /= Mag;
	} else {
		v->x = 0.0;
		v->y = 0.0;
		v->z = 0.0;
	}
}

void CrossProduct(Vector * v1, Vector * v2, Vector * v3)
{
	v3->x = (v1->y * v2->z) - (v1->z * v2->y);
	v3->y = (v1->z * v2->x) - (v1->x * v2->z);
	v3->z = (v1->x * v2->y) - (v1->y * v2->x);	
}

void AbsoluteVector(Vector * v)
{
	v->x = fabs(v->x);
	v->y = fabs(v->y);
	v->z = fabs(v->z);
}

float VectorMagnitudeSquared(Vector * v) {
  return ((v->x * v->x) + (v->y * v->y) + (v->z * v->z));
}

float VectorMagnitude(Vector * v)
{
	return sqrt(v->x * v->x + v->y * v->y + v->z * v->z);
}

void RotateVector(Vector * Look, Vector * rotate)
{
	Vector NewLook;
	Vector NewRot;
	
	float angle, x, y, z, CosAngle, SinAngle;
	
	angle = VectorMagnitude(rotate);
	CosAngle = cos(angle);
	SinAngle = sin(angle);
	
	NewRot = *rotate;
	NormalizeVector(&NewRot);
	x = NewRot.x;
	y = NewRot.y;
	z = NewRot.z;
	
	NewLook.x =  (CosAngle + (1 - CosAngle) * x) * Look->x;
	NewLook.x += ((1 - CosAngle) * x * y - z * SinAngle) * Look->y;
	NewLook.x += ((1 - CosAngle) * x * z + y * SinAngle) * Look->z;
	
	NewLook.y =  ((1 - CosAngle) * x * y + z * SinAngle) * Look->x;
	NewLook.y += (CosAngle + (1 - CosAngle) * y) * Look->y;
	NewLook.y += ((1 - CosAngle) * y * z - x * SinAngle) * Look->z;
	
	NewLook.z =  ((1 - CosAngle) * x * z - y * SinAngle) * Look->x;
	NewLook.z += ((1 - CosAngle) * y * z + x * SinAngle) * Look->y;
	NewLook.z += (CosAngle + (1 - CosAngle) * z) * Look->z;
	
	*Look = NewLook;
}