Crashes when drawing layers

[mothmann]

Code: [Select]

//Main.cpp
#include "stdafx.h"
#include <SFML\System.hpp>
#include <SFML\Window.hpp>
#include <SFML\Graphics.hpp>
#include <string>
#include "Layer.h"
#include <iostream>

int stagew = 1280;
int stageh = 720;
int stagebpp = 32;

int _tmain(int argc, _TCHAR* argv[])
{

Layer lay;
sf::Sprite * spr;
sf::Image ima;
if (ima.LoadFromFile("graphics/tiles.bmp")==true)
std::cout << "good";
spr->SetImage(ima);

lay.push_back(spr);

sf::RenderWindow App(sf::VideoMode(stagew,stageh,stagebpp), "x");

while(App.IsOpened())
{
App.Clear();
App.Draw(lay);// this nor App.Draw((*spr)); will work. they both crash.
App.Display();
}
return 0;
}

why is this crashing?? it post GOOD

here is my layer code

Code: [Select]

#pragma once
#include <vector>
#include <SFML/Graphics.hpp>

typedef std::vector<sf::Drawable*> FrameSet;
typedef FrameSet::const_iterator itFrame;

class Layer : public sf::Drawable, public FrameSet {
 public :
   Layer(  const sf::Vector2f& Position = sf::Vector2f(0, 0),
                const sf::Vector2f& Scale = sf::Vector2f(1, 1),
                float Rotation = 0.f,
                const sf::Color& Col = sf::Color(255, 255, 255, 255));
   virtual ~Layer();

   virtual void Render(sf::RenderTarget& Target) const;
};

Code: [Select]

#include "StdAfx.h"
#include "Layer.h"
#include <iostream>

Layer::Layer(   const sf::Vector2f& Position,
                const sf::Vector2f& Scale,
                float Rotation,
                const sf::Color& Col) :
sf::Drawable(Position,Scale,Rotation,Col)
{
};
 
Layer::~Layer(){
};

void Layer::Render(sf::RenderTarget& Target) const {
    for( itFrame i = begin() ;i!=end();i++)
            Target.Draw(*(*i));
};

[Laurent]

Your spr pointer doesn't point to a valid instance of sf::Sprite.

[devlin]

To clarify:

Code: [Select]

sf::Sprite * spr;
sf::Image ima;
if (ima.LoadFromFile("graphics/tiles.bmp")==true)
    std::cout << "good";
spr->SetImage(ima);
spr is unallocated - you have to new it (line 1 in the snippet above) if you for some reason want to keep using pointers.

[Nexus]

if you for some reason want to keep using pointers.

Since there is none (at least in this example), you should prefer automatic objects.

Code: [Select]

sf::Sprite spr;
// ...

[mothmann]

thats what i get for coding half asleep.