我正在阅读gameinsitute的c ++编程课程,并且有一个运算符重载的例子,我经常得到一个
main.cpp | 20 |错误:'v + w'中的'operator +'不匹配
我不知道问题出在哪里。
的main.cpp
// main.cpp
#include "Vector3.h"
#include <iostream>
using namespace std;
int main()
{
float coords[3] = {1.0f, 2.0f, 3.0f};
Vector3 u;
Vector3 v(coords);
Vector3 w(-5.0f, 2.0f, 0.0f);
cout << "u = "; u.print();
cout << "v = "; v.print();
cout << "w = "; w.print();
cout << endl;
u = v + w; // this gives the error
cout << "v + w = ";
u.print();
cout << endl;
v.normalize();
cout << "unit v = ";
v.print();
cout << "v.length() = "<< v.length() << endl;
cout << endl;
float dotP = u * w; // this also gives error
cout << "u * w = " << dotP << endl;
float* vArray = v.toFloatArray();
cout <<
"[0] = " << vArray[0] << ", "
"[1] = " << vArray[1] << ", "
"[2] = " << vArray[2] << endl <<endl;
cout << "Input vector..." << endl;
Vector3 m;
m.input();
cout << "m = ";
m.print();
return 0;
}
Vector3.h
#ifndef VECTOR3_H
#define VECTOR3_H
#include <iostream>
class Vector3
{
public:
// constructors
Vector3();
Vector3(float coords[3]);
Vector3(float x, float y, float z);
Vector3(const Vector3& vec);
// methods
float length();
void normalize();
float* toFloatArray();
void print();
void input();
// operators
Vector3 operator=(const Vector3& rhs);
Vector3 operator+(const Vector3& rhs) const;
Vector3 operator-(const Vector3& rhs) const;
float operator*(const Vector3& rhs) const;
Vector3 operator*(float scalar) const;
// fields
float mX;
float mY;
float mZ;
};
#endif // VECTOR3_H
Vector3.cpp
#include "Vector3.h"
#include <cmath>
#include <iostream>
using std::cout;
using std::cin;
Vector3::Vector3()
{
mX = 0.0f;
mY = 0.0f;
mZ = 0.0f;
}
Vector3::Vector3(float coords[3])
{
mX = coords[0];
mY = coords[1];
mZ = coords[2];
}
Vector3::Vector3(float x, float y, float z)
{
mX = x;
mY = y;
mZ = z;
}
Vector3::Vector3(const Vector3& vec)
{
mX = vec.mX;
mY = vec.mY;
mZ = vec.mZ;
}
float Vector3::length()
{
return sqrt(mX*mX + mY*mY + mZ*mZ);
}
void Vector3::normalize()
{
float len = length();
mX /= len;
mY /= len;
mZ /= len;
}
float* Vector3::toFloatArray()
{
return &mX;
}
void Vector3::print()
{
cout << "<" << mX << ", " << mY << ", " << mZ << "> \n";
}
void Vector3::input()
{
cout << "Enter x: ";
cin >> mX;
cout << "Enter y: ";
cin >> mY;
cout << "Enter z: ";
cin >> mZ;
}
//operators
Vector3 Vector3::operator=(const Vector3& rhs)
{
Vector3 vTemp;
vTemp.mX = rhs.mX;
vTemp.mY = rhs.mY;
vTemp.mZ = rhs.mZ;
return vTemp;
}
Vector3 Vector3::operator+(const Vector3& rhs) const
{
Vector3 sum;
sum.mX = mX + rhs.mX;
sum.mY = mY + rhs.mY;
sum.mZ = mZ + rhs.mZ;
return sum;
}
Vector3 Vector3::operator-(const Vector3& rhs) const
{
Vector3 dif;
dif.mX = mX - rhs.mX;
dif.mY = mY - rhs.mY;
dif.mZ = mZ - rhs.mZ;
return dif;
}
float Vector3::operator*(const Vector3& rhs) const
{
float dotP = mX*rhs.mX + mY*rhs.mY + mZ*rhs.mZ;
return dotP;
}
Vector3 Vector3::operator*(float scalar) const
{
Vector3 p;
p.mX = mX * scalar;
p.mY = mY * scalar;
p.mZ = mZ * scalar;
return p;
}
提前感谢您的帮助!
答案 0 :(得分:1)
您的operator+
没有任何问题 - 这是您的operator=
错误导致operator+
没有做您认为正在做的事情的结果。修复将解决您的问题。
Vector3 Vector3::operator=(const Vector3& rhs)
{
mX = rhs.mX;
mY = rhs.mY;
mZ = rhs.mZ;
return *this;
}
答案 1 :(得分:-1)
在旁注中,这些重载中存在一些问题,您将返回本地引用。对不起,这不是一个答案,我可能会为此付出代价,但仍然:
以例如operator =为例。它应该是
Vector3& Vector3::operator=(const Vector3& rhs)
{
this->mX = rhs.mX;
this->mY = rhs.mY;
this->mZ = rhs.mZ;
return (*this);
}
否则你将返回一个本地引用,一旦该函数退出,它将是垃圾。运算符+ - 同样的问题。 至于运算符*,你正在做一个点积,这与向量乘法不同。为此我建议编写一个名为dot()的函数,它接受另一个向量并在self和2nd向量之间执行点积
或者您应该使用Eigen library
如果您可以提供我们如何编译您的代码,也许我们可以提供帮助