Is it possible to have an array of different objects that come from the same base class?

Question

I'm trying to design a weapons class for a game. This is some of the code I have come up with to fit my needs:

class weapon {

 public:
  int fireRate;
  int bulletDamage;
  int range;
  ofImage sprite;
  ofImage bulletSprite;
  bullet bullets[50];
  int activeBullet;

 public:
  void fire();
};

class machineGun: public weapon {
 public: 
  void fire();
};

class flamer: public weapon {
 public: 
  void fire();
};

And then I would like to define a weapons array like so:

//Weapon variables
const int totalWeapons = 2;
int currentWeapon = 1;
weapon weapons[totalWeapons];

I would like element [0] to represent the machineGun class and element [1] to represent the flamer class. Am I going about this problem the correct way? Should I refactor this in some way? How do I achieve an array that holds these two different weapons?

The idea is so when I call weapons[0].fire(); I get a machineGun class and when I call weapons[1].fire(); I get flamer fire.

---

Edit: Thanks for helping guys. I'm having a few problems with using "weapons[0] = new machineGun;". I get an error "cannot allocate an array of constant size 0" when I try to run this code.

Has anyone got any insight into why this isn't working? My updated code looks something like this:

//Weapon variables
const int totalWeapons = 2;
int currentWeapon = 1;
weapon weapons[totalWeapons];
weapons[0] = new machineGun;
weapons[1] = new flamer;

But I get lots of errors:

1>gameplay.cpp(49) : error C2466: cannot allocate an array of constant size 0
1>gameplay.cpp(49) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>gameplay.cpp(49) : error C2371: 'weapons' : redefinition; different basic types
1>        gameplay.cpp(48) : see declaration of 'weapons'
1>gameplay.cpp(49) : error C2440: 'initializing' : cannot convert from 'machineGun *' to 'int []'
1>        There are no conversions to array types, although there are conversions to references or pointers to arrays
1>gameplay.cpp(50) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>gameplay.cpp(50) : error C2369: 'weapons' : redefinition; different subscripts
1>        gameplay.cpp(48) : see declaration of 'weapons'
1>gameplay.cpp(50) : error C2440: 'initializing' : cannot convert from 'flamer *' to 'int [1]'
1>        There are no conversions to array types, although there are conversions to references or pointers to arrays

---

I have taken another different approach and gotten some different errors. I'm still pretty unsure how this is all meant to glue together.

//Weapon variables
const int totalWeapons = 2;
int currentWeapon = 1;
weapon weapons[totalWeapons] = {new machineGun, new flamer};

With errors:

1>gameplay.cpp(48) : error C2275: 'machineGun' : illegal use of this type as an expression
1>        gameplay.h(36) : see declaration of 'machineGun'
1>gameplay.cpp(48) : error C2275: 'flamer' : illegal use of this type as an expression
1>        gameplay.h(41) : see declaration of 'flamer'

---

The answer ended up being something like this:

//Weapon variables
const int totalWeapons = 2;
int currentWeapon = 1;
weapon *weapons[totalWeapons] = {new machineGun, new flamer};

Thanks everyone who helped me get my head around this!

Answer 1

#include <iostream>

class weapon {

 public:
  int fireRate;
  int bulletDamage;
  int range;
  int activeBullet;

 public:
  virtual void fire(void) {std::cout << "machine " << '\n';}
  virtual ~weapon() {std::cout << "destructor is virtual" << '\n';}
};

class machineGun: public weapon {
 public: 
  void fire(void) {std::cout << "machine gun firing" << '\n';}
  ~machineGun(void) { std::cout << "machine gun destroyed" << '\n';}
};

class flamer: public weapon {
 public: 
  void fire(void) {std::cout << "flamer firing" << '\n';}
  ~flamer(void) {std::cout << "flamer destroyed" << '\n';}
};

int main(void)
{
    const int count = 2;
    weapon *weapons[count];

    machineGun *a = new machineGun();
    flamer     *b = new flamer();

    weapons[0] = a;
    weapons[1] = b;

    weapons[0]->fire();
    weapons[1]->fire();

    delete a;
    delete b;

}

Answer 2

As noted by Ross, your array has to be of type weapon* to allow you to downcast specialized weapon types.

So,

weapon* weapons[totalWeapons];
weapons[0] = new machineGun;

Also as noted, as you're creating these dynamically, you'll want to make sure that you clean them up later or you're going to run into memory leaks