Polymorphism not happening? c++

#include <iostream>
#include <vector>
#include <windows.h>
 
/*
  Parent class to all objects which are part of the main game loop.
  Examples:
  static props
  physics props
  players
  enemies
  vehicles
  explosion handlers
  triggers
*/
class CgameObject{
public:
  long x,y; //location
  bool awake, visible;
 
  //constructor
  CgameObject(long setX,long setY){
    x = setX;
    y = setY;
    visible = true;
    awake = true;
  }
 
  virtual void step(){};
};
 
#include <cmath>
/*
  Objects which have basic motion properties,
  eg:
  players
  enemies
  vehicles
  physics props
*/
class CmotionObject : public CgameObject{
public:
  double direction, //angle in degrees going anticlockwise from the +ve x axis
  speed, //speed in pixels/frame along the direction (+ve or -ve)
  vSpeed, //speed in pixels/frame along the y axis, down being +ve
  hSpeed; //speed in pixels/frame along the x axis, right being +ve
 
public:
  //constructor
  CmotionObject(long setX,long setY):CgameObject(setX,setY){
    vSpeed = 0;
    hSpeed = 0;
    speed = 0;
    direction = 0;
  }
 
  virtual void applyMotion(){
    x += (long)hSpeed;
    y += (long)vSpeed;
  }
 
  /*
    No getters required I think.
  */
  virtual void setVSpeed(double newSpeed){
  }
 
  virtual void setHSpeed(double newSpeed){
  }
 
  virtual void setSpeed(double newSpeed){
  }
 
  virtual void setDirection(double newDirection){
  }
};
 
using namespace std;
unsigned int i;
unsigned long frameCount;
 
#include "classes/gameObject.h"
#include "classes/motionObject.h"
vector <CgameObject> gameObjects;
 
class Cplayer : public CmotionObject{
public:
  Cplayer(long setX,long setY):CmotionObject(setX,setY){};
 
  //do this every frame
  void step(){
    applyMotion();
    cout << "player is at " << x << endl;
    if(x < 100){
      if(x >= 100) cout << frameCount << ", player has reached the finishing line\n";
      hSpeed = 0; //stop moving
    }
  }
 
};
 
class Cnpc : public CmotionObject{
protected:
  int npcNumber;
 
public:
  //constructor
  Cnpc(long setX,long setY,int setNpcNumber):CmotionObject(setX,setY){
    npcNumber = setNpcNumber;
  }
 
  //do this every frame
  void step(){
    applyMotion();
    cout << "npc #" << npcNumber << " is at " << x << endl;
    if(x < 100){
      if(x >= 100) cout << frameCount << ", npc has reached the finishing line\n";
      hSpeed = 0; //stop moving
    }
  }
 
};
 
int main(){
  frameCount = 0;
 
  gameObjects.push_back(Cplayer(0,30));
  gameObjects.push_back(Cnpc(1,0,10));
  gameObjects.push_back(Cnpc(2,0,20));
  gameObjects[0].hSpeed = 4;
 
  while(true){
    for(i = 0;i < gameObjects.size();i ++){
      gameObjects[i].step();
    }
    frameCount ++;
    cout << "frame #" << frameCount << " completed\n";
    Sleep(100); //10 fps
  }
  return 0;
}
 
 

class PS2Sprite
{
public:
   PS2Sprite();
   ~PS2Sprite();
   virtual void Render(void);
};
 
class PS2SpriteT : public PS2Sprite
{
public:
   PS2SpriteT();
   ~PS2SpriteT();
   void Render(void);
};