Messages

1

Graphics / Re: Drawable object inheritance

« on: March 17, 2017, 01:55:39 pm »

Woaaah, it was so obvious that I am angry at myself I didn't notice it.

Yes - thank you, you're right.

I use new operator because my class Button doesn't have default constructor, so I cannot declare it as a Menu class member like: Button b1 (it causes compilation error - no default constructor for Button class)

2

Graphics / Drawable object inheritance

« on: March 17, 2017, 01:39:34 pm »

I have class Menu that inherits from public Drawable and override draw method and owns Button class instance.

class Menu  : public sf::Drawable
{
    public:
        Menu();
        virtual ~Menu();
    protected:
    private:
        virtual void draw(sf::RenderTarget& target, sf::RenderStates states) const;

        Button* m_Button_3x3;
        Button* m_Button_9x9;
        Button* m_Button_16x16;
        Button* m_Button_99x99;

        sf::Sprite* m_Sprite3x3;
        sf::Sprite*  m_Sprite_9x9;
        sf::Sprite*  m_Sprite_16x16;
        sf::Sprite*  m_Sprite_99x99;

        sf::Texture m_texture;
};
 

It uses constructor to define Sprites and Buttons:

Menu::Menu()
{
    m_texture.loadFromFile("menu.png");

    m_Sprite3x3 = new sf::Sprite(m_texture, sf::IntRect(0,0,400,300));

    m_Sprite_9x9 = new sf::Sprite(m_texture, sf::IntRect(400,0,800,300));
    m_Sprite_9x9->setPosition(400, 0);

    m_Sprite_16x16 = new sf::Sprite(m_texture, sf::IntRect(0,300,400,600));
    m_Sprite_16x16->setPosition(0, 300);

    m_Sprite_99x99 = new sf::Sprite(m_texture, sf::IntRect(400,300,800,600));
    m_Sprite_99x99->setPosition(400, 300);


    Button* m_Button_3x3 = new Button(m_Sprite3x3);
    Button* m_Button_9x9 = new Button(m_Sprite_9x9);
    Button* m_Button_16x16 = new Button(m_Sprite_16x16);
    Button* m_Button_99x99 = new Button(m_Sprite_99x99);
}

It contains Buttons that I want to display by using theirs overridden function draw:

class Button    : public sf::Drawable
{
    friend class Menu;
    public:
        Button(sf::Sprite* sprite);
        virtual ~Button();
    protected:
    private:
        virtual void draw(sf::RenderTarget& target, sf::RenderStates states) const;
        sf::Sprite m_sprite;

};
 

Here's function draw with global extern window (window is only one so I think it's not too bad to have it as a global var):

void Button::draw(sf::RenderTarget& target, sf::RenderStates states) const
{
    extern sf::RenderWindow app;
    app.draw(m_sprite);
}

but somehow I cannot call Buttons::draw in Menu::draw : - causes Segfault

void Menu::draw(sf::RenderTarget& target, sf::RenderStates states) const
{
    extern sf::RenderWindow app;

    m_Button_3x3->draw(app, states);
    }
 

that causes Segfault as well:

void Menu::draw(sf::RenderTarget& target, sf::RenderStates states) const
{
    extern sf::RenderWindow app;

   app.draw(*m_Button_3x3);
}
 

works only that but it's not elegant - moreover - it displays correctly but causes segfault when app is closing:

void Menu::draw(sf::RenderTarget& target, sf::RenderStates states) const
{
    extern sf::RenderWindow app;

   app.draw(*m_Sprite3x3);
}
 

So what is correct way to inherit Drawable in dervied class? Like
app.draw(menu) ->
   menu::draw(){app.draw(button)}->
      button::draw(){app.draw(member_button_sprite)}
Is it a more elegant, clever way to do that?

3

General discussions / Including SFML headers - specific or whole modules?

« on: February 24, 2017, 09:44:23 am »

Hi,

I don't know if that's good principle that I follow but I always try to be as much specific and precisely as I can in my programs.
So the question is - should I include whole module e.g

#include <SFML/Graphics.hpp>

or should I use specific header with functions I need:

#include <SFML/Graphics/Texture.hpp>

For now I prefer 2nd way because it doesn't include whole bunch of classes that I do not need.
What is good practise? And is it just for SFML or in general?