嵌入式C++类交互

我正在继续一个嵌入式微控制器(Arduino)的游戏,我有一个关于课堂互动的问题——这个问题延续了我之前的问题 here 我的代码基于sheddenizen的建议(请参阅“此处”中对给定链接的响应):

我有三个从基类继承的类-

(i) 类精灵 -(低音类)在LCD上具有位图形状和(x,y)位置

(ii) 类导弹:公共精灵 -有一个特定的形状(x,y),也有一个obj

(iii) 类外星人:公共精灵 -具有特定形状,并且(x,y)

(iv) 职业选手:公共精灵 - ""

它们都有不同的(虚拟)移动方法,并显示在LCD上:

我的精简代码如下-具体来说,我只希望导弹在特定条件下发射:当导弹被创建时,它采用对象(x,y)值,我如何访问继承类中传递的对象值?

// Bass class - has a form/shape, x and y position 
// also has a method of moving, though its not defined what this is  
class Sprite
{
  public:
    Sprite(unsigned char * const spacePtrIn, unsigned int xInit, unsigned int yInit);
    virtual void Move() = 0;
    void Render() { display.drawBitmap(x,y, spacePtr, 5, 6, BLACK); }
    unsigned int X() const { return x; } 
    unsigned int Y() const { return y; }
  protected:
    unsigned char *spacePtr;
    unsigned int x, y;
};

// Sprite constructor
Sprite::Sprite(unsigned char * const spacePtrIn, unsigned int xInit, unsigned int yInit)
{
  x = xInit;
  y = yInit;
  spacePtr = spacePtrIn;
}

/*****************************************************************************************/
// Derived class "Missile", also a sprite and has a specific form/shape, and specific (x,y) derived from input sprite
// also has a simple way of moving
class Missile : public Sprite
{
public:
   Missile(Sprite const &launchPoint): Sprite(&spaceMissile[0], launchPoint.X(), launchPoint.Y()) {}
   virtual void Move();
};

void Missile::Move()
{
  // Here - how to access launchPoint.X() and launchPoint.Y() to check for 
  // "fire conditions" 
  y++;
  Render();
}


// create objects
Player HERO;
Alien MONSTER;
Missile FIRE(MONSTER);

// moving objects 
HERO.Move(); 
MONSTER.Move();
FIRE.Move();