/***
*
*	Copyright (c) 1996-2002, Valve LLC. All rights reserved.
*	
*	This product contains software technology licensed from Id 
*	Software, Inc. ("Id Technology").  Id Technology (c) 1996 Id Software, Inc. 
*	All Rights Reserved.
*
*   Use, distribution, and modification of this source code and/or resulting
*   object code is restricted to non-commercial enhancements to products from
*   Valve LLC.  All other use, distribution, or modification is prohibited
*   without written permission from Valve LLC.
*
****/
//  Vector.h
// A subset of the extdll.h in the project HL Entity DLL
//
#pragma once
#ifndef UTIL_VECTOR_H
#define UTIL_VECTOR_H

// Misc C-runtime library headers
#include "stdio.h"
#include "stdlib.h"
#include "math.h"

// Header file containing definition of globalvars_t and entvars_t
typedef unsigned int func_t;					//
typedef int string_t;				// from engine's pr_comp.h;
typedef float vec_t;				// needed before including progdefs.h

//=========================================================
// 2DVector - used for many pathfinding and many other 
// operations that are treated as planar rather than 3d.
//=========================================================
class Vector2D
{
public:
	inline Vector2D( void )					{ }
	inline Vector2D( float X, float Y )			{ x = X; y = Y; }
	inline Vector2D operator+( const Vector2D& v )	const	{ return Vector2D(x+v.x, y+v.y); }
	inline Vector2D operator-( const Vector2D& v )	const	{ return Vector2D(x-v.x, y-v.y); }
	inline Vector2D operator*( float fl )		const	{ return Vector2D(x*fl, y*fl); }
	inline Vector2D operator/( float fl )		const	{ return Vector2D(x/fl, y/fl); }

	inline float Length( void )						const	{ return (float)sqrt(x*x + y*y );		}

	inline Vector2D Normalize( void ) const
	{
		Vector2D vec2;

		float flLen = Length();
		if( flLen == 0 )
		{
			return Vector2D( (float)0, (float)0 );
		}
		else
		{
			flLen = 1 / flLen;
			return Vector2D( x * flLen, y * flLen );
		}
	}

	vec_t	x, y;
};

inline float DotProduct( const Vector2D& a, const Vector2D& b ) { return( a.x * b.x + a.y * b.y ); }
inline Vector2D operator*( float fl, const Vector2D& v ) { return v * fl; }

//=========================================================
// 3D Vector
//=========================================================
class Vector						// same data-layout as engine's vec3_t,
{								//which is a vec_t[3]
public:
	// Construction/destruction
	inline Vector( void )					{ }
	inline Vector( float X, float Y, float Z )		{ x = X; y = Y; z = Z; }
	inline Vector( double X, double Y, double Z )		{ x = (float)X; y = (float)Y; z = (float)Z; }
	inline Vector( int X, int Y, int Z )			{ x = (float)X; y = (float)Y; z = (float)Z; }
	inline Vector( const Vector& v )			{ x = v.x; y = v.y; z = v.z; } 
	inline Vector( float rgfl[3] )				{ x = rgfl[0]; y = rgfl[1]; z = rgfl[2]; }

	// Operators
	inline Vector operator-( void ) const			{ return Vector( -x, -y, -z ); }
	inline int operator==( const Vector& v ) const		{ return x == v.x && y == v.y && z == v.z; }
	inline int operator!=( const Vector& v ) const		{ return !( *this == v ); }
	inline Vector operator+( const Vector& v ) const	{ return Vector( x + v.x, y + v.y, z + v.z ); }
	inline Vector operator-( const Vector& v ) const	{ return Vector( x - v.x, y - v.y, z - v.z ); }
	inline Vector operator*( float fl ) const		{ return Vector( x * fl, y * fl, z * fl ); }
	inline Vector operator/( float fl ) const		{ return Vector( x / fl, y / fl, z / fl ); }
	
	// Methods
	inline void CopyToArray( float* rgfl ) const		{ rgfl[0] = x, rgfl[1] = y, rgfl[2] = z; }
	inline float Length( void ) const			{ return (float)sqrt( x * x + y * y + z * z); }
	operator float *()					{ return &x; } // Vectors will now automatically convert to float * when needed
	operator const float *() const				{ return &x; } // Vectors will now automatically convert to float * when needed
	inline Vector Normalize( void ) const
	{
		float flLen = Length();
		if( flLen == 0 ) return Vector( 0, 0, 1); // ????
		flLen = 1 / flLen;
		return Vector( x * flLen, y * flLen, z * flLen );
	}

	inline Vector2D Make2D( void ) const
	{
		Vector2D Vec2;

		Vec2.x = x;
		Vec2.y = y;

		return Vec2;
	}

	inline float Length2D( void ) const
	{
		return (float)sqrt( x * x + y * y );
	}

	// Members
	vec_t x, y, z;
};

inline Vector operator*( float fl, const Vector& v ) { return v * fl; }
inline float DotProduct( const Vector& a, const Vector& b) { return( a.x * b.x + a.y * b.y + a.z * b.z ); }
inline Vector CrossProduct(const Vector& a, const Vector& b) { return Vector( a.y * b.z - a.z * b.y, a.z * b.x - a.x * b.z, a.x * b.y - a.y * b.x ); }

#define vec3_t Vector
#endif // UTIL_VECTOR_H