sdl_loadbmp from file without using entire file path - c++

Question

I'm trying to load an image from file without using the entire file path. Like in C#, However everything I try just throws my sdl error in the console when it gets to loading the image.
bool loadMedia()
{
//Loading success flag
bool success = true;
//Load splash image
gHelloWorld = SDL_LoadBMP( "SDL2_tutorials02/hello_world.bmp" );
if( gHelloWorld == NULL )
{
printf( "Unable to load image %s! SDL Error: %s\n", "SDL2_tutorials02/hello_world.bmp", SDL_GetError() );
success = false;
}
return success;
}
This is part of my original code that I learned from an online tutorial, trying to teach myself SDL and more about c++
edit for InternetAussie, this is my entire source code from what I think I have learned from the tutorial is below:
//Using SDL and standard IO
#include <SDL.h>
#include <stdio.h>
//Screen dimension constants
const int SCREEN_WIDTH = 640;
const int SCREEN_HEIGHT = 480;
//Starts up SDL and creates window
bool init();
//Loads media
bool loadMedia();
//Frees media and shuts down 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;
bool init()
{
//Initialization flag
bool success = true;
//Initialize SDL
if( SDL_Init( SDL_INIT_VIDEO ) < 0 )
{
printf( "SDL could not initialize! SDL_Error: %s\n", SDL_GetError() );
success = false;
}
else
{
//Create window
gWindow = SDL_CreateWindow( "SDL Tutorial", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN );
if( gWindow == NULL )
{
printf( "Window could not be created! SDL_Error: %s\n", SDL_GetError() );
success = false;
}
else
{
//Get window surface
gScreenSurface = SDL_GetWindowSurface( gWindow );
}
}
return success;
}
bool loadMedia()
{
//Loading success flag
bool success = true;
//Load splash image
gHelloWorld = SDL_LoadBMP( "SDL2_tutorials02/hello_world.bmp" );
if( gHelloWorld == NULL )
{
printf( "Unable to load image %s! SDL Error: %s\n", "SDL2_tutorials02/hello_world.bmp", SDL_GetError() );
success = false;
}
return success;
}
void close()
{
//Deallocate surface
SDL_FreeSurface( gHelloWorld );
gHelloWorld = NULL;
//Destroy window
SDL_DestroyWindow( gWindow );
gWindow = NULL;
//Quit SDL subsystems
SDL_Quit();
}
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 );
}
}
//system halt for testing
system("pause");
//Free resources and close SDL
close();
return 0;
}
and if it helps I followed the instructions in tutorial 1 at Lazy Foo' Productions. The hyperlink that I hope I have appropriately added is just the setup part after clicking through the steps on how to setup sdl on a windows machine using visual studios 2010 ultimate. I went with the system 32 setup using the console as my output source for errors.

Answer 1

As InternetAussie already said if you are running the compiled executable all the paths are relative to the directory your executable runs from.
What your problem seems to be is related to your IDE. When you build and run code from your IDE the working directory is taken from somewhere else. It can be some default path where your IDE builds debug versions of your program. It's hard to tell exactly because it's different for all of them.
If you want to debug your SDL project you should set the working directory for compiler to the directory you are compiling your executable into and where you also have your files you want to read saved.
F. e. : if you are using visual studio you can set this by right clicking on a project > settings > debugging > working path option or if you build your project with cmake you can also set it with SET_PROPERTY(TARGET Project_name PROPERTY VS_DEBUGGER_WORKING_DIRECTORY "path").
If this didn't solve your problem, feel free to ask questions. Also if you are using cmake and VS, I can provide you with a complete cmakelists.txt that generates SDL2 project for VisualStudio and set's up all required settings.