Point3d, Класс 3-мерной точки. Опции

[motoden]

Создал класс 3-мерной точки, т.к. не нашел готового в библиотеке. QPoint реализован только для 2-мерного случая. Представляю его на ваш суд. Кто что думает?

class Point3D{
public:
    Point3D(){
        val_x = 0;
        val_y = 0;
        val_z = 0;
    }

    Point3D(double in_x,
            double in_y,
            double in_z){
        val_x = in_x;
        val_y = in_y;
        val_z = in_z;
    }

    Point3D(Point3D &in_point3d){
        val_x = in_point3d.x();
        val_y = in_point3d.y();
        val_z = in_point3d.z();
    }

    Point3D operator + (Point3D in_point3d){
        Point3D result;
        result.setX(val_x + in_point3d.x());
        result.setY(val_y + in_point3d.y());
        result.setZ(val_z + in_point3d.z());
        return result;
    }

    Point3D operator += (Point3D in_point3d){
        qDebug()<<"+=";
        val_x += in_point3d.x();
        val_y += in_point3d.y();
        val_z += in_point3d.z();
        return (*this);
    }

    Point3D operator * (Point3D in_point3d){
        Point3D result;
        result.setX(val_x * in_point3d.x());
        result.setY(val_y * in_point3d.y());
        result.setZ(val_z * in_point3d.z());
        return result;
    }

    Point3D operator *= (Point3D in_point3d){
        val_x *= in_point3d.x();
        val_y *= in_point3d.y();
        val_z *= in_point3d.z();
        return *this;
    }

    double x(){
        return val_x;
    }

    double y(){
        return val_y;
    }

    double z(){
        return val_z;
    }

    void setX(double in_x){
        val_x = in_x;
    }

    void setY(double in_y){
        val_y = in_y;
    }

    void setZ(double in_z){
        val_z = in_z;
    }

private:
    double val_x;
    double val_y;
    double val_z;
};