I’m new to C++, and I’m trying to simply pass an array to a class constructor whilst using object-oriented programming, but I keep getting the error “C2040 ‘matPtr’: ‘Matrix3D’ differs in levels of indirection from ‘float *'”. Here is the code:

Main.cpp –

#include <GL/glut.h>
#include "Matrix3D.h"

void display(void) {
    //...
    float mat[3][3] = { {1, 2, 3}, {4, 5, 6}, {7, 8, 9} };
    float* matPtr = &mat[0][0]
    Matrix3D(matPtr);
    //...
}

int main(int argc, char** argv) {
    //OpenGL stuff not really being used at the moment...
    glutDisplayFunc(display);
    //...
}

Matrix3D.h –

#include <GL/glut.h>
#include <iostream>
#ifndef __MATRIX_H__
#define __MATRIX_H__

class Matrix3D {
private:
    float mat[3][3] = { {1, 0, 0}, {0, 1, 0}, {0, 0, 1} };
public:
    Matrix3D() {}
    Matrix3D(float* matPtr) {
        for (int i = 0, n = 0; i < sizeof(this->mat) / sizeof(this->mat[0]); i++) {
            for (int j = 0; j < sizeof(this->mat[0]) / sizeof(this->mat[i][0]); j++, n++) {
                this->mat[i][j] = *(matPtr + n);
            }
        }
        //Print array code...
    }
};

#endif