Multiple Iterations of the Same Class

[MottMan]

This is a problem I've had before but have always dismissed. It has caused several personal projects to be ignored and cancelled due to my inability to find a way around it.

Basically, my problem is that I'm not sure how to have a program create more instances of a class based upon a number given by a user. My current use is in a game akin to the Dungeon Crawler practice project somewhere in this forum but it's going to have a level editor. So when the user wants to have 5 monsters, how do I create those 5 during runtime?

Any help would be great. Thanks for reading.

[zb0S216C]

Either use std::vector^[1] or implement your own growable array, like I have; it's relatively easy.

References:
^[1] http://www.cplusplus.com/reference/stl/vector/

_Wazzak

[Vins3Xtreme]

use dynamic allocation, using malloc() for C or the 'new' operator for C++.

[MottMan]

@Framework

I was planning on holding all of the monsters/obstacles/etc in a vector but I'm more confused on how to initialize the dynamic amount of monsters/obstacles/etc beforehand.

@Vins3Xtreme

I haven't looked at new for a very long time. I guess it's time to go back and see how it can help. Thanks.

[zb0S216C]

With a std::vector, its size can grow on cue; therefore, it can grow during run-time. Also, you don't have to allocate any memory for it to function; that's do automatically. The std::vector allocates, or reserves, a region of memory initially for new elements. When the reserved memory is exhausted, a new region of memory is allocated, then contents of the old vector are transferred over to the new vector.

_Wazzak

[AdventWolf]

I feel your pain, std::vector/std::list is what you are looking for.
Just create a vector of the class you need to store and add or remove as many as you need.

class Monster;

std::vector<Monster> monsterList;

Monster dragon;
Monster zombie;

monsterList.push_back(dragon);
monsterList.push_back(dragon);
monsterList.push_back(zombie);

If you want the user to choose to add a certain amount of monsters, then get that number from the user and do a loop to push_back() that amount.

int monsterCount;
cin >> monsterCount;

for( int x = 0; x < monsterCount; x++ )
     monsterList.push_back(goblin);

[MottMan]

@AdventWolf

Your condolences are met kindly.

So you can simply use the same instance of a class (the Monster named dragon) over and over again despite being a single instance? Does that mean all Monsters named dragon will have the same data and not looked at as individuals?

[AdventWolf]

So you can simply use the same instance of a class (the Monster named dragon) over and over again despite being a single instance?

Yes, because when you push back an instance into the container, it creates a copy of that instance.

Does that mean all Monsters named dragon will have the same data and not looked at as individuals?

You can create multiple versions of dragons.

class Monster
{
    Monster(string nam, int hp,)
    {
        name = nam;
        health = hp;
    }
    string name;
    int health;
}

Monster dragon1("Dragon",20);
Monster dragon2("Dragon",30);

The variable names here are different but they are still "Dragons."