如何从另一个源文件调用main.cpp中的静态函数？

Question

I have a method called initializeObjects() in my main.cpp file, and I want to call it from a method in another source file, named Scene.cpp . How do I do that? This is my main.cpp file, without the headers:

static void initializeObjects();
int main() {
    Scene myScene;
    myScene.render(640,480);
    return 0;
}

void initializeObjects(){
    //Add a plane of gray color
    Scene::shapes.push_back(std::make_shared<Plane>(Vector3D(0,1,1), Vector3D(0,0,80), COLOR_GRAY));
    //Add two spheres
    Scene::shapes.push_back(std::make_shared<Sphere>(100.0, Vector3D(0,50,0), COLOR_WHITE));
    Scene::shapes.push_back(std::make_shared<Sphere>(60.0,ORIGIN, COLOR_RED));
}

Answer 1

When you define a function with storage class specifier static , you explicitly say that you want this function to have an internal linkage - this means it should not be visible outside the translation unit where it is defined.

So to be able to call your function from some other translation unit (Scene.cpp), drop static specifier, and add declaration of your function to header file, which should be included by this other (Scene.cpp) translation unit.