enum class as array index

Scoped enums (enum class) are not implicitly convertible to integers. You need to use a static_cast:

SDL_Surface*KEY_PRESS_SURFACES[static_cast<int>(KeyPressSurfaces::KEY_PRESS_SURFACE_TOTAL)];

Remove the class keyword or cast explicitly to an integral type.

You can convert your enum to int using template function and you will get more readable code:

#include <iostream>
#include <string>
#include <typeinfo>

using namespace std;

enum class KeyPressSurfaces: int {
    KEY_PRESS_SURFACE_DEFAULT,
    KEY_PRESS_SURFACE_UP,
    KEY_PRESS_SURFACE_DOWN,
    KEY_PRESS_SURFACE_LEFT,
    KEY_PRESS_SURFACE_RIGHT,
    KEY_PRESS_SURFACE_TOTAL
};

template <typename E>
constexpr typename std::underlying_type<E>::type to_underlying(E e) {
    return static_cast<typename std::underlying_type<E>::type>(e);
}


int main() {
    KeyPressSurfaces val = KeyPressSurfaces::KEY_PRESS_SURFACE_UP;
    int valInt = to_underlying(val);
    std::cout << valInt << std::endl;
    return 0;
}

I fount to_underlying function here