/**
 * @file llvector4.cpp
 * @brief LLVector4 class implementation.
 *
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 * Copyright (c) 2000-2009, Linden Research, Inc.
 *
 * Second Life Viewer Source Code
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 */

#include "linden_common.h"

#include "llvector3.h"
#include "llvector4.h"
#include "llmatrix4.h"
#include "llmatrix3.h"
#include "llquaternion.h"

// LLVector4

// Axis-Angle rotations

#if 0
const LLVector4& LLVector4::rotVec(F32 angle, const LLVector4& vec)
{
	if (angle && !vec.isExactlyZero())
	{
		*this = *this * LLMatrix4(angle, vec);
	}
	return *this;
}

const LLVector4& LLVector4::rotVec(F32 angle, F32 x, F32 y, F32 z)
{
	LLVector3 vec(x, y, z);
	if (angle && !vec.isExactlyZero())
	{
		*this = *this * LLMatrix4(angle, vec);
	}
	return *this;
}
#endif

const LLVector4& LLVector4::rotVec(const LLMatrix4& mat)
{
	*this = *this * mat;
	return *this;
}

const LLVector4& LLVector4::rotVec(const LLQuaternion& q)
{
	*this = *this * q;
	return *this;
}

const LLVector4& LLVector4::scaleVec(const LLVector4& vec)
{
	mV[VX] *= vec.mV[VX];
	mV[VY] *= vec.mV[VY];
	mV[VZ] *= vec.mV[VZ];
	mV[VW] *= vec.mV[VW];

	return *this;
}

// Sets all values to absolute value of their original values. Returns true if
// data changed.
bool LLVector4::abs()
{
	bool ret = false;

	if (mV[0] < 0.f) { mV[0] = -mV[0]; ret = true; }
	if (mV[1] < 0.f) { mV[1] = -mV[1]; ret = true; }
	if (mV[2] < 0.f) { mV[2] = -mV[2]; ret = true; }
	if (mV[3] < 0.f) { mV[3] = -mV[3]; ret = true; }

	return ret;
}

std::ostream& operator<<(std::ostream& s, const LLVector4& a)
{
	s << "{ " << a.mV[VX] << ", " << a.mV[VY] << ", " << a.mV[VZ]
	  << ", " << a.mV[VW] << " }";
	return s;
}

// Non-member functions

F32 angle_between(const LLVector4& a, const LLVector4& b)
{
	LLVector4 an = a;
	LLVector4 bn = b;
	an.normalize();
	bn.normalize();
	F32 cosine = an * bn;
	F32 angle = cosine >= 1.f ? 0.f
							  : (cosine <= -1.f ? F_PI : acosf(cosine));
	return angle;
}

bool are_parallel(const LLVector4& a, const LLVector4& b, F32 epsilon)
{
	LLVector4 an = a;
	LLVector4 bn = b;
	an.normalize();
	bn.normalize();
	F32 dot = an * bn;
	return 1.f - fabsf(dot) < epsilon;
}

LLVector3 vec4to3(const LLVector4& vec)
{
	return LLVector3(vec.mV[VX], vec.mV[VY], vec.mV[VZ]);
}

LLVector4 vec3to4(const LLVector3 &vec)
{
	return LLVector4(vec.mV[VX], vec.mV[VY], vec.mV[VZ]);
}