Question

Firstly, i am sorry if the title does not properly describe my problem, but i could not think of a better one. =/

I am trying to make a game where all entities that I need to draw on the screen are children of an Actor class.

The actor class has a virtual function called “virtual void drawMe()” that is overridden by the children to specify how it should be drawn.

Ergo, at the end of the game loop, I want to draw all actors. I created a “vector allActors” to help me with this and every time I create a new actor I do this: “allActors.push_back( &newActor )“. So far so good (I think).

To draw them at the end of the loop I iterate through all elements in allActors and call “allActors[i]->drawMe()” for each one.

But I discovered that this method will not work for actors that I created locally, like the bullets created when the character shoots (they are created inside an if statement).
I think it is because while I save the address of the bullets in the allActors vector, the actors themselves are destroyed after the if statement ends, so it’s an address to nothing.

example:

if ( characterShot == true)
{
    Bullet newBullet;
    allActors.push_back( &newBullet );
    characterShot = false;
}

I have no idea of how to do this in a way that it works, because I can only create the bullet actors IF the character shoots!

Please help me figure out a better and more functional way to do what I want.

Thank you in advance!

Answer 1

Allocate the object dynamically:

allActors.push_back(new Bullet);

Note that the lifetime management will be a genuine nightmare; you should make the container elements some sort of smart pointer (ideally std::unique_ptr<Bullet> or some suitable base class).