c#封装三维向量，另外也看了下别人的C++封装

一、 c#实现

/*
Vector3 Definition
Created by taotao man on 2016-4-12
brief:封装三位向量类Vector3
// 修改记录：
date:
add SetA()
Change GetA();
*/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ceshi
{
public class Vector3
{
private float x;
private float y;
private float z;
private const float E = 0.0000001f;

public float X
{
set { x = value; }
get { return x; }
}

public float Y
{
set { y = value; }
get { return y; }
}

public float Z
{
set { z = value; }
get { return z; }
}

public Vector3(float x, float y, float z)
{
this.x = x;
this.y = y;
this.z = z;
}

public Vector3(Vector3 vct)
{
this.x = vct.x;
this.y = vct.y;
this.z = vct.z;
}

//向量加法
public static Vector3 operator +(Vector3 a, Vector3 b)
{
Vector3 result = new Vector3(a.x + b.x , a.y + b.y, a.z +b.z);
return result;
}

//向量减法
public static Vector3 operator -(Vector3 a, Vector3 b)
{
Vector3 result = new Vector3(a.x - b.x, a.y - b.y, a.z - b.z);
return result;
}

//向量除以一个数
public static Vector3 operator /(Vector3 a, float b)
{
if (b != 0)
{
return new Vector3(a.x / b, a.y / b, a.z / b);
}
else
{
return new Vector3(0, 0, 0);
}
}

// 左乘一个数
public static Vector3 operator *(float a, Vector3 b)
{
return new Vector3(a * b.x, a * b.y, a * b.z);
}

// 右乘一个数
public static Vector3 operator *(Vector3 a, float b)
{
return new Vector3(a.x * b, a.y * b, a.z * b);
}

// 向量的点乘
public static float operator *(Vector3 a, Vector3 b)
{
return a.x * b.x + a.y * b.y + a.z * b.z;
}

// 判断两个向量是否相等
public static bool operator ==(Vector3 a, Vector3 b)
{
if (Math.Abs(a.x - b.x) < E && Math.Abs(a.y - b.y) < E && Math.Abs(a.z - b.z) < E)
{
return true;
}
else
return false;
}

// 判断两个向量不等
public static bool operator !=(Vector3 a, Vector3 b)
{
return !(a == b);
}

public override bool Equals(object obj)
{
return base.Equals(obj);
}

public override int GetHashCode()
{
return base.GetHashCode();
}

public override string ToString()
{
return base.ToString();
}

// 向量叉积
public static Vector3 Cross(Vector3 a, Vector3 b)
{
return new Vector3(a.y * b.z - a.z * b.y,
a.z * b.x - a.x * b.z,
a.x * b.y - a.y * b.x);
}

//向量的模
public static float Magnitude(Vector3 a)
{
return (float)Math.Sqrt(a.x * a.x + a.y * a.y + a.z * a.z);
}

// 单位化向量

public static Vector3 Normalize(Vector3 a)
{
float magnitude = Magnitude(a);
return new Vector3(a.x / magnitude, a.y / magnitude, a.z / magnitude);
}
}
}

#include <math.h>

class Vector3
{
public:
float x, y, z;

// 默认构造函数
Vector3(){}
// 复制构造函数
Vector3(const Vector3 &a) : x(a.x), y(a.y), z(a.z){}
//
// 带参数的构造函数，用三个值完成初始化
Vector3(float nx, float ny, float nz) : x(nx), y(ny), z(nz){}
// 标准对象操作
// 重载运算符，并返回引用，以实现左值
Vector3 &operator = (const Vector3 &a)
{
x = a.x; y = a.y; z = a.z;
return *this;
}
//
//重载“==”操作符
bool operator == (const Vector3 &a) const
{
return x == a.x && y == a.y && z == a.z;
}
bool operator != (const Vector3 &a) const
{
return x != a.x || y != a.y || z != a.z;
}

//向量运算
// 置为零向量
void zero()
{
x = y = z =0.0f;
}
// 重载一元“-”运算符
Vector3 operator -()const
{
return Vector3(-x, -y , -z);
}
//重载二元“+”和“-”运算符
Vector3 operator +(const Vector3 &a) const
{
return Vector3(x + a.x, y + a.y, z + a.z);
}
Vector3 operator -(const Vector3 &a) const
{
return Vector3(x - a.x, y - a.y, z - a.z);
}
// 与标量的乘除法
Vector3 operator * (float a) const
{
return Vector3(x * a, y * a, z * a);
}
Vector3 operator / (float a) const
{
float oneOverA = 1.0f / a;
return Vector3(x * oneOverA, y * oneOverA, z * oneOverA);
}
// 重载自反运算符
Vector3 &operator += (const Vector3 &a)
{
x += a.x; y += a.y; z += a.z;
return *this;
}
Vector3 &operator -= (const Vector3 &a)
{
x -= a.x; y -= a.y; z -= a.z;
return *this;
}
Vector3 &operator *= (float a)
{
x *= a; y *= a; z *= a;
return * this;
}
Vector3 &operator /= (float a)
{
float oneOverA = 1.0f / a;
x *= oneOverA; y *= oneOverA; z *= oneOverA;
return *this;
}
// 向量标准化
void normalize()
{
float magSq = x * x + y * y + z * z;
if(magSq > 0.0f)
{
float oneOverMag = 1.0f / sqrt(magSq);
x *= oneOverMag;
y *= oneOverMag;
z *= oneOverMag;
}
}
// 向量点乘，重载标准的乘法运算符
float operator *(const Vector3 &a) const
{
return x * a.x + y * a.y + z * a.z;
}
};

// 非成员函数
// 求向量模
inline float vectorMag(const Vector3 &a)
{
return sqrt(a.x * a.x + a.y * a.y + a.z * a.z);
}
//计算两个向量的叉乘
inline Vector3 crossProduct(const Vector3 &a, const Vector3 &b)
{
return Vector3
(a.y * b.z - a.z * b.y, a.z * b.x - a.x * b.z, a.x * b.y - a.y * b.x);
}
//
//实现标量左乘
inline Vector3 operator *(float k, const Vector3 &v)
{
return Vector3(k * v.x, k * v.y, k * v.z);
}
// 计算两点间的距离
inline float distance(const Vector3 &a, const Vector3 &b)
{
float dx = a.x - b.x;
float dy = a.y - b.y;
float dz = a.x - b.z;
return sqrt(dx * dx + dy * dy + dz * dz);
}
//提供一个全局零向量
extern const Vector3 kZeroVector;