Problems Threading A Window

[7krs]

Hi,

the code works, it's just that the return code is weird:

#include <SFML/Graphics.hpp>
sf::RenderWindow wnd;

void sig()
{
    wnd.setActive(true);
    wnd.clear(sf::Color::Green);
    wnd.display();
    wnd.setActive(false);
}

int main()
{
    wnd.create(sf::VideoMode(800, 600, 32), "Title", sf::Style::Default);
    wnd.setActive(false);
    sf::Thread ap(sig);
    ap.launch();
    ap.wait();
    return 0;
}
 

This is a minimal example, and it returns 234, or 0xEA in hex.

#include <SFML/Graphics.hpp>
sf::RenderWindow wnd;

void sig()
{
    wnd.setActive(true);
    wnd.clear(sf::Color::Green);
    wnd.display();
}

int main()
{
    wnd.create(sf::VideoMode(800, 600, 32), "Title", sf::Style::Default);
    wnd.setActive(false);
    sf::Thread ap(sig);
    ap.launch();
    ap.wait();
    return 0;
}
 

Will cause a segmentation fault and return 139 (0x8B).

What am I doing wrong?

[Laurent]

Don't declare your window in global scope.

[7krs]

Problem is I don't, in practice the window is located in a class, and the thread is in another dedicated to drawing.

[Nexus]

And the instance of that class is not global?

Can you represent your problem in a minimal example like above, but with the window as a function-local variable?

[7krs]

No, not a single instance is global.

#include <SFML/Graphics.hpp>

class Draw
{
public:
    Draw()
    {
    }
    void start()
    {
        thr = new sf::Thread(&Draw::drawer, this);
        thr->launch();
    }
    void setWindow(sf::RenderWindow *wind)
    {
        wnd = wind;
    }
private:
    void drawer()
    {
        wnd->setActive(true);
        wnd->clear(sf::Color::Green);
        wnd->display();
        wnd->setActive(false);
    }
    sf::Thread *thr;
    sf::RenderWindow *wnd;
};

int main()
{
    sf::RenderWindow window(sf::VideoMode(800, 600, 32), "Title", sf::Style::Default);
    Draw object;
    window.setActive(false);
    object.setWindow(&window);
    object.start();
    sf::sleep(sf::seconds(2)); // So the thread can finish in peace.
    return 0;
}

returns 234.

[Laurent]

returns 234

How do you see that? Does it crash? If so, have you tried to run the debugger?

[7krs]

returns 234

How do you see that? Does it crash? If so, have you tried to run the debugger?

It comes up in the little terminal window like that. And no it doesn't crash, it just exits this way.


Yes, I have tried the debugger, but I can't seem to step into return 0; (Where dtors are called). The debugger finishes just fine.