/*********************************************************************************************
*
*	raylib.vector3
*
*	Vector3 Functions Definition
*
*	Copyright (c) 2013 Ramon Santamaria (Ray San - raysan@raysanweb.com)
*	
*	This software is provided "as-is", without any express or implied warranty. In no event 
*	will the authors be held liable for any damages arising from the use of this software.
*
*	Permission is granted to anyone to use this software for any purpose, including commercial 
*	applications, and to alter it and redistribute it freely, subject to the following restrictions:
*
*	  1. The origin of this software must not be misrepresented; you must not claim that you 
*	  wrote the original software. If you use this software in a product, an acknowledgment 
*	  in the product documentation would be appreciated but is not required.
*
*	  2. Altered source versions must be plainly marked as such, and must not be misrepresented
*	  as being the original software.
*
*	  3. This notice may not be removed or altered from any source distribution.
*
**********************************************************************************************/

#include "vector3.h"

#include <math.h>

// Add two vectors
Vector3 VectorAdd(Vector3 v1, Vector3 v2)
{
	Vector3 out;

	out.x = v1.x + v2.x;
	out.y = v1.y + v2.y;
	out.z = v1.z + v2.z;
	
	return out;
}

// Substract two vectors
Vector3 VectorSubtract(Vector3 v1, Vector3 v2)
{
	Vector3 out;

	out.x = v1.x - v2.x;
	out.y = v1.y - v2.y;
	out.z = v1.z - v2.z;
	
	return out;
}

// Calculate two vectors cross product
Vector3 VectorCrossProduct(Vector3 v1, Vector3 v2)
{
	Vector3 cross;

	cross.x = v1.y*v2.z - v1.z*v2.y;
	cross.y = v1.z*v2.x - v1.x*v2.z;
	cross.z = v1.x*v2.y - v1.y*v2.x;
	
	return cross;
}

// Calculate one vector perpendicular vector
Vector3 VectorPerpendicular(Vector3 v) 
{
	Vector3 out;
	
    float min = fabs(v.x);
    Vector3 cardinalAxis = {1.0, 0.0, 0.0};
 
    if (fabs(v.y) < min) 
	{
        min = fabs(v.y);
        cardinalAxis = (Vector3){0.0, 1.0, 0.0};
    }
 
    if(fabs(v.z) < min) 
	{
        cardinalAxis = (Vector3){0.0, 0.0, 1.0};
    }
	
	out = VectorCrossProduct(v, cardinalAxis);
 
    return out;
}

// Calculate two vectors dot product
float VectorDotProduct(Vector3 v1, Vector3 v2)
{
	float dot;
	
	dot = v1.x*v2.x + v1.y*v2.y + v1.z*v2.z;
	
	return dot;
}

// Calculate vector lenght
float VectorLength(const Vector3 v)
{
	float length;
	
	length = sqrt(v.x*v.x + v.y*v.y + v.z*v.z);
	
	return length;
}

// Scale provided vector
void VectorScale(Vector3 *v, float scale)
{
	v->x *= scale;
	v->y *= scale;
	v->z *= scale;
}

// Invert provided vector (direction)
void VectorInverse(Vector3 *v)
{
	v->x = -v->x;
	v->y = -v->y;
	v->z = -v->z;
}

// Normalize provided vector
void VectorNormalize(Vector3 *v)
{
	float length, ilength;

	length = VectorLength(*v);
	
	if (length == 0) length = 1;

	ilength = 1.0/length;
	
	v->x *= ilength;
	v->y *= ilength;
	v->z *= ilength;
}