Estou fazendo meus primeiros passos no SDL (C ++) e peguei alguns tutoriais no site www.

Mas há um problema. Eu instalei o SDL2 no meu Linux Mint System, compilei o código do tutorial:

#ifdef __cplusplus
    #include <cstdlib>
#else
    #include <stdlib.h>
#endif

#include <stdio.h>
#include <SDL2/SDL.h>

#include <iostream>

int main ( int argc, char** argv )
{
    if (SDL_Init(SDL_INIT_EVERYTHING) != 0){
        std::cout << "SDL_Init Error: " << SDL_GetError() << std::endl;
        return 1;
    }

    SDL_Window *win = SDL_CreateWindow("Hello World!", 100, 100, 640, 480,
    SDL_WINDOW_SHOWN);
    if (win == NULL){
        std::cout << "SDL_CreateWindow Error: " << SDL_GetError() << std::endl;
        return 1;
    }

    SDL_Renderer *ren = SDL_CreateRenderer(win, -1,
    SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
    if (ren == NULL){
        std::cout << "SDL_CreateRenderer Error: " << SDL_GetError() << std::endl;
        return 1;
    }

    SDL_Surface *bmp = SDL_LoadBMP("cb.bmp");
    if (bmp == NULL){
        std::cout << "SDL_LoadBMP Error: " << SDL_GetError() << std::endl;
        return 1;
    }

    SDL_Texture *tex = SDL_CreateTextureFromSurface(ren, bmp);
    SDL_FreeSurface(bmp);
    if (tex == NULL){
        std::cout << "SDL_CreateTextureFromSurface Error: "
            << SDL_GetError() << std::endl;
        return 1;
    }

    SDL_Delay(4000);

    SDL_DestroyTexture(tex);
    SDL_DestroyRenderer(ren);
    SDL_DestroyWindow(win);
    SDL_Quit();

    return 0;
}

com este comando de compilação:

g++ main.cpp -lSDL2 -o prog

E eu entendi isso:

Uma moldura de janela sem qualquer interior. Onde eu tenho que procurar por issoerro?

Código final

Primeiro: graças a estrelar!

#ifdef __cplusplus
    #include <cstdlib>
#else
    #include <stdlib.h>
#endif

#include <stdio.h>
#include <SDL2/SDL.h>

#include <iostream>

int main ( int argc, char** argv )
{

    if (SDL_Init(SDL_INIT_EVERYTHING) != 0){
        std::cout << "SDL_Init Error: " << SDL_GetError() << std::endl;
        return 1;
    }

    SDL_Window *window = SDL_CreateWindow("Hello World!", 100, 100, 640, 480,
    SDL_WINDOW_SHOWN);
    if (window == NULL){
        std::cout << "SDL_CreateWindow Error: " << SDL_GetError() << std::endl;
        return 1;
    }
/*
    SDL_Renderer *ren = SDL_CreateRenderer(window, -1,
    SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
    if (ren == NULL){
        std::cout << "SDL_CreateRenderer Error: " << SDL_GetError() << std::endl;
        return 1;
    }
*/
    SDL_Surface *surface_bmp = SDL_LoadBMP("cb.bmp");
    if (surface_bmp == NULL){
        std::cout << "SDL_LoadBMP Error: " << SDL_GetError() << std::endl;
        return 1;
    }
/*
    SDL_Texture *tex = SDL_CreateTextureFromSurface(ren, surface_bmp);
    SDL_FreeSurface(surface_bmp);
    if (tex == NULL){
        std::cout << "SDL_CreateTextureFromSurface Error: "
            << SDL_GetError() << std::endl;
        return 1;
    }
*/

    SDL_Surface *surface_window = SDL_GetWindowSurface(window);

    /*
     * Copies the bmp surface to the window surface
     */
    SDL_BlitSurface(surface_bmp,
                    NULL,
                    surface_window,
                    NULL);

    /*
     * Now updating the window
     */
    SDL_UpdateWindowSurface(window);

    /*
     * This function used to update a window with OpenGL rendering.
     * This is used with double-buffered OpenGL contexts, which are the default.
     */
/*    SDL_GL_SwapWindow(window); */

    SDL_Delay(5000);

/*    SDL_DestroyTexture(tex);*/
/*    SDL_DestroyRenderer(ren);*/
    SDL_DestroyWindow(window);
    SDL_Quit();

    return 0;
}

Mostre-me este resultado :)

Vi que era realmente fácil. E dessa forma eu não preciso do openGL para desenhar. Este será o próximo passo. Seria bom, se você me ajudar a melhorar este exemplo para obtê-lo com o openGL para ...