Vector/Classes hierarchy issues

[tristan1333]

I have a vector which stores things of type abilities, I have a subtype from abilities called power_stab. I'm trying to use push_back(power_stab] however... Well I'm new to using class hierarchy.

I suppose the question is, how would I push_back something of type power_stab to std::vector<abilities> abilities?
Here are the relevant classes:

class abilities
{
public:
	int ID;
	int last_cast;
	int cooldown;
	const std::string icon;
	void cast()
	{
		return;
	};
	bool can_cast()
	{
		if(this->last_cast + this->cooldown < SDL_GetTicks())
		{
			return true;
		}
		return false;
	}
	abilities();
};

class power_stab : public abilities
{
public:
	abilities::ID = 0;
	abilities::cooldown = 5000;
	abilities::icon = "resources/abilities/power_strike.png";
	void cast()
	{
		return;
	};
	power_stab();
};

class character
{
	public:
		std::vector<abilities> abilities;
		int char_ID;
};

[keskiverto]

You can't.

Think a class as a box. The box contains some values. A derived class is a larger box that contains both the box of the base class and other values.

The vector stores boxes of fixed size. You can push_pack a power_stab object because power_stab IS-A abilities, but it will only make a copy of the abililties box. That is called slicing.


What you seek is polymorphism. Make the vector contain pointers like std::unique_ptr or std::shared_ptr.


PS. does the "abilities" on line 39 refer to the "abilities" or "abilities"? Even if the compiler would be okay with that, it sure looks ambiguous.

[tristan1333]

Ah alright thanks! I'll mark as solved.