Question

So I wanted to make a game with really clean code and good organization. Looking into game states I found this site: http://gamedevgeek.com/tutorials/managing-game-states-in-c/

Using his templates, I have this so far:

GameState.hpp

#ifndef Rect_Game_GameState_hpp
#define Rect_Game_GameState_hpp

#include <SFML/Graphics.hpp>
#include "GameEngine.hpp"

class GameEngine;

class GameState {

public:
    virtual void Init() = 0;
    virtual void Cleanup() = 0;

    virtual void Pause() = 0;
    virtual void Resume() = 0;

    virtual void HandleEvents(GameEngine* game) = 0;
    virtual void Update(GameEngine* game) = 0;
    virtual void Draw(GameEngine* game) = 0;

    virtual void ChangeState(GameEngine* game, GameState* state);

private: 
    GameState() { }
};

#endif

TitleScreenState.hpp

#ifdef Rect_Game_TitleScreenState_hpp
#def Rect_Game_TitleScreenState_hpp

#include <iostream>
#include <SFML/Graphics.hpp>
#include "GameState.hpp"
#include "GameEngine.hpp"

class TitleScreenState : public GameState {

public:
    void Init();
    void Cleanup();

    void Pause();
    void Resume();

    void HandleEvents(GameEngine* engine);
    void Update(GameEngine* engine);
    void Draw(GameEngine* engine);

    void ChangeState(GameEngine* engine, GameState* state);

    static TitleScreenState* Instance();

private:

    TitleScreenState() {}

    static TitleScreenState* titleScreenInstance;

    sf::RenderWindow* window;

    int mouseX;
    int mouseY;

    Button* playButton;

};

#endif

And then the error “Use of undeclared identifier ‘TitleScreenState'” appears every time I try to implement the functions. It’s not auto-completing “TitleScreenState” either. Any suggestions?

TitleScreenState.cpp

#include <iostream>
#include "GameEngine.hpp"
#include "GameState.hpp"
#include "TitleScreenState.hpp"
#include "ResourcePath.hpp"



void TitleScreenState::Init()
{
    // Initialize values
    leftClick = false;
    mouseX = 0;
    mouseY = 0;

    // Load title screen image
    sf::Texture titleImage;
    if (!titleImage.loadFromFile(resourcePath() + "TitleScreen.png"))
        printf("could not load TitleScreen.png");

    sf::Sprite titleScreen;
    titleScreen.setTexture(titleImage);

    playButton = new Button("Play", 350, 220);

}

Answer 1

The problem here is TitleScreenState.hpp:

#ifdef Rect_Game_TitleScreenState_hpp
#def Rect_Game_TitleScreenState_hpp

First, the #ifdef prevents the compiler from seeing the rest of the file, because Rect_Game_TitleScreenState_hpp hasn’t been defined. Therefore, it should have been #ifndef. In addition, the #def should have been #define. That should solve the problem.