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/*This source code copyrighted by Lazy Foo' Productions (2004-2013)
and may not be redistributed without written permission.*/
 
//Using SDL and standard IO
#include "core.h"
 
int main( int argc, char* args[] )
{
    //Start up SDL and create window
    if( !init() )
        {
            printf( "Failed to initialize!\n" );
        }
    else
    {
        //Load media
        if( !loadMedia() )
            {
                printf( "Failed to load media!\n" );
            }
        else
            {
                //Apply the image
                SDL_BlitSurface( gHelloWorld, NULL, gScreenSurface, NULL );
            
                //Update the surface
                SDL_UpdateWindowSurface( gWindow );
 
                //Wait two seconds
                SDL_Delay( 2000 );
            }
    }
 
    //Free resources and close SDL
    close();
 
    return 0;
}

#include <SDL.h>
#include <stdio.h>
//==============================================================================
    //Розширення
    const int SCREEN_WIDTH = 640;
    const int SCREEN_HEIGHT = 480;
    const char WindowTitle[] = "My Game";
//==============================================================================
    //Запуск SDL2 і створення вікон
    bool init();
    //Завантаження медіа
    bool loadMedia();
    //Очишчення медіа та вимкнення SDL
    void close();
    //The window we'll be rendering to
    SDL_Window* gWindow = NULL; 
    //The surface contained by the window
    SDL_Surface* gScreenSurface = NULL;
    //The image we will load and show on the screen
    SDL_Surface* gHelloWorld = NULL;
//==============================================================================

#include "core.h"
//==============================================================================
void close()
{
    //Deallocate surface
    SDL_FreeSurface( gHelloWorld );
    gHelloWorld = NULL;
 
    //Destroy window
    SDL_DestroyWindow( gWindow );
    gWindow = NULL;
 
    //Quit SDL subsystems
    SDL_Quit();
}
//==============================================================================

//==============================================================================
void close()
{
    extern SDL_Window* gWindow;
    extern SDL_Surface* gScreenSurface;
    extern SDL_Surface* gHelloWorld;
    //Deallocate surface
    SDL_FreeSurface( gHelloWorld );
    gHelloWorld = NULL;
 
    //Destroy window
    SDL_DestroyWindow( gWindow );
    gWindow = NULL;
 
    //Quit SDL subsystems
    SDL_Quit();
}
//==============================================================================

 //The window we'll be rendering to
    SDL_Window* gWindow = NULL; 
    //The surface contained by the window
    SDL_Surface* gScreenSurface = NULL;
    //The image we will load and show on the screen
    SDL_Surface* gHelloWorld = NULL;

// объявления без определения
extern SDL_Window* gWindow;
extern SDL_Surface* gScreenSurface;
extern SDL_Surface* gHelloWorld;