Inheritance of operator overloads - c++

Question

I'm having an issue with the inheritance of my operator overloading functions in my derived class.
#pragma once
#include "Math.hpp"
using namespace Math;
class Euler
{
public:
float x, y, z;
Euler();
Euler(const float &, const float &, const float &);
float &operator[](const char &) const;
Euler &operator=(const Euler &);
Euler &operator+=(const Euler &);
Euler &operator-=(const Euler &);
Euler &operator*=(const float &);
Euler &operator/=(const float &);
Euler operator+(const Euler &) const;
Euler operator-(const Euler &) const;
Euler operator*(const float &) const;
Euler operator/(const float &) const;
bool operator==(const Euler &) const;
bool operator!=(const Euler &) const;
bool IsValid() const;
void Clear();
};
inline Euler::Euler()
{
x = y = z = 0.f;
}
inline Euler::Euler(const float &_x, const float &_y, const float &_z)
{
x = _x;
y = _y;
z = _z;
}
inline float &Euler::operator[](const char &c) const
{
return ((float *)this)[c];
}
inline Euler &Euler::operator=(const Euler &e)
{
x = e.x;
y = e.y;
z = e.z;
return *this;
}
inline Euler &Euler::operator+=(const Euler &e)
{
x += e.x;
y += e.y;
z += e.z;
return *this;
}
inline Euler &Euler::operator-=(const Euler &e)
{
x -= e.x;
y -= e.y;
z -= e.z;
return *this;
}
inline Euler &Euler::operator*=(const float &e)
{
x *= e;
y *= e;
z *= e;
return *this;
}
inline Euler &Euler::operator/=(const float &e)
{
x /= e + M_FLT_EPSILON;
y /= e + M_FLT_EPSILON;
z /= e + M_FLT_EPSILON;
return *this;
}
inline Euler Euler::operator+(const Euler &e) const
{
return Euler(x + e.x, y + e.y, z + e.z);
}
inline Euler Euler::operator-(const Euler &e) const
{
return Euler(x - e.x, y - e.y, z - e.z);
}
inline Euler Euler::operator*(const float &f) const
{
return Euler(x * f, y * f, z * f);
}
inline Euler Euler::operator/(const float &f) const
{
return Euler(x / (f + M_FLT_EPSILON), y / (f + M_FLT_EPSILON), z / (f + M_FLT_EPSILON));
}
inline bool Euler::operator==(const Euler &e) const
{
return e.x == x && e.y == y && e.z == z;
}
inline bool Euler::operator!=(const Euler &e) const
{
return e.x != x || e.y != y || e.z != z;
}
inline bool Euler::IsValid() const
{
using namespace std;
return isfinite(x) && isfinite(y) && isfinite(z);
}
inline void Euler::Clear()
{
x = y = z = 0.f;
}
class Vector : public Euler
{
public:
using Euler::Euler;
void Rotate(const Angle &);
void Rotate2D(const float &);
float Length() const;
float LengthSqr() const;
float Length2D() const;
float Length2DSqr() const;
float DistTo(const Vector &) const;
float DistToSqr(const Vector &) const;
};
inline float Vector::Length() const
{
return Sqrt((x * x) + (y * y) + (z * z));
}
inline float Vector::LengthSqr() const
{
return (x * x) + (y * y) + (z * z);
}
inline float Vector::Length2D() const
{
return Sqrt((x * x) + (y * y));
}
inline float Vector::Length2DSqr() const
{
return (x * x) + (y * y);
}
inline float Vector::DistTo(const Vector &v) const
{
return (*this - v).Length();
}
inline float Vector::DistToSqr(const Vector &v) const
{
return (*this - v).LengthSqr();
}
The code shown below contains an error in the distto and DistToSqr function wherein it calculates (*this - v) as the superclass Euler and therefore cannot find the length function.
I was wondering why this would be as this code compiles on my laptop and not my desktop.
I'd be grateful if anyone could show me why this code doesn't work and what is the best course in fixing it.
It seems like doing this is a plausible way to fix it.
inline float Vector::DistTo(const Vector &v) const
{
Vector tmp = (*this - v);
return tmp.Length();
}
Still wondering if this is the best option to fix it though.

Answer 1

I'm going to assume that it is likely that Euler is always used as a base type of a more specific type? If so, you can might be able to solve this using the CRTP pattern. Here is a subset of your code in this style:
#include <cmath>
template <typename Derived>
class Euler
{
public:
float x, y, z;
Euler();
Euler(const float &, const float &, const float &);
template <typename T>
Derived & operator-=(Euler<T> const &);
template <typename T>
Derived operator-(Euler<T> const &) const;
private:
Derived & derived() const {
return static_cast<Derived &>(*this);
}
Derived const & derived() {
return static_cast<Derived const &>(*this);
}
};
template <typename Derived>
Euler<Derived>::Euler() : x(0), y(0), z(0)
{}
template <typename Derived>
Euler<Derived>::Euler(const float &_x, const float &_y, const float &_z)
: x(_x), y(_y), z(_z)
{}
template <typename Derived>
template <typename T>
Derived & Euler<Derived>::operator-=(Euler<T> const & e)
{
x -= e.x;
y -= e.y;
z -= e.z;
return derived();
}
template <typename Derived>
template <typename T>
Derived Euler<Derived>::operator-(Euler<T> const & e) const
{
return Derived(x - e.x, y - e.y, z - e.z);
}
class Vector : public Euler<Vector>
{
public:
using Euler<Vector>::Euler;
float Length() const;
float DistTo(const Vector &) const;
};
inline float Vector::Length() const
{
return std::sqrt(x * x + y * y + z * z);
}
inline float Vector::DistTo(const Vector & v) const
{
return (*this - v).Length();
}