c2011 error c++ when trying to do polymorphism - c++

Question

I'm trying to achieve polymorphism with my image manipulation program. I keep getting this error, I think it is caused from me defining scale twice in both the header file and the cpp file.
Error C2011 'scale': 'class' type redefinition
and I am not sure what to do. Thanks for any help.
.cpp file
Image *begin= new Image(750, 750);
begin->read("picture1.jpg");
Image *enlarged= new Image(1500, 1500);
scale *pass= new scale(*imgScale);
pass->manipulator(1500, 1500);
pass->load("manipulated.jpg");
class scale : public Image
{
public:
scale(Image const &firstimg)
{
w = firstimg.w;
h = firstimg.h;
pixels = firstimg.pixels;
}
void manipulator(int w2, int h2)
{
Image *temp = new Image(w2, h2);
float x_ratio = (float )w / w2;
float y_ratio = (float )h / h2;
float px, py;
for (int i = 0; i < h2; i++)
{
for (int j = 0; j < w2; j++)
{
px = floor(j*x_ratio);
py = floor(i*y_ratio);
temp->pixels[(i*w2) + j] = this->pixels[(int)((py*w) + px)];
}
}
}
};
header file
#pragma once
#ifndef manipulator_H
#define manipulator_H
class scale : public Image
{
public:
scale(Image const &firstimg);
void manipulator(int w2, int h2);
};
#endif

Answer 1

You are declaring you class Scale in two different files, in the algo header file and in the .cpp file. Actually, I don't know why are how using inheritance if you are creating a new Image in your zoom function.
Your header, scale.h should be something like that:
#pragma once
#ifndef ALGORITHMS_H
#define ALGORITHMS_H
class Image;
class Scale {
public:
explicit Scale(Image const &beginImg);
void zoom(int w2, int h2);
private:
// Here all your private variables
int w;
int h;
¿? pixels;
};
#endif
And your cpp file, scale.cpp:
#include "scale.h"
#include "image.h"
Scale::Scale(Image const &beginImg) :
w(beginImg.w),
h(beginImg.h),
pixels(beginImg.pixels) {}
void Scale::zoom(int w2, int h2){
Image *temp = new Image(w2, h2);
double x_ratio = (double)w / w2;
double y_ratio = (double)h / h2;
double px, py;
// rest of your code;
}
And, then in the place you want to use this class, example your main:
int main() {
Image *imgScale = new Image(750, 750);
imgScale->readPPM("Images/Zoom/zIMG_1.ppm");
Scale *test = new Scale(*imgScale);
test->zoom(1500, 1500);
test->writePPM("Scale_x2.ppm");
delete imgScale;
delete test;
return 0;
}
In any case, consider using smart pointers instead of raw pointers and take a look in to the different modifications I did.