So i'm studying this SFML book, And this is a section that confuses me quite a bit, i know what it does, and what every thing means, its specifically the syntax in which its used.
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Game::Game()
: mWindow(sf::VideoMode(640, 480), "SFML Application")
, mPlayer()
{
mPlayer.setRadius(40.f);
mPlayer.setPosition(100.f, 100.f);
mPlayer.setFillColor(sf::Color::Cyan);
}
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I do understand that this is declaring the function of the default constructor in class "Game". What i do not understand is the use of : to then use an earlier defined function. I've never seen that before. The only use of a single : i know of is to inherit from other classes. (or to declare functions) like
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class Example2 {
public:
int total;
Example2 (int initial_value) : total(initial_value) { }; // <--- that
void accumulate (int x) { total += x; };
};
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OR
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class thing : public thingy{ // <---- that
}
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But back to the original question , i dont understand, using one : in the default constructor?
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Game::Game()
: mWindow(sf::VideoMode(640, 480), "SFML Application")
, mPlayer()
{
mPlayer.setRadius(40.f);
mPlayer.setPosition(100.f, 100.f);
mPlayer.setFillColor(sf::Color::Cyan);
}
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also this is the class declaration (for reference to variables)
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class Game
{
public:Game();
void run();
private:
void processEvents();
void update();
void render();
private:
sf::RenderWindow mWindow;
sf::CircleShape mPlayer;
};
int main()
{
Game game;
game.run();
}
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EDIT:now that i look at my post. I just realized, that i semi answered my own question. it is declaring a function but when i posted what i knew with the empty brackets, what there doing is actually putting something in those brackets.I mostly learned c++ from this site, these tutorials don't show use of that. Which is probably why i got confused.
