Use constants for window size

main.cpp

@@ -20,10 +20,11 @@ int main()
 
 	/// [2] Create components
 	// [2.1] Create window
-	SDL_Surface* screen = SDL_SetVideoMode(640, 480, 32, SDL_HWSURFACE|SDL_DOUBLEBUF);
+	const int width(640), height(480);
+	SDL_Surface* screen = SDL_SetVideoMode(width, height, 32, SDL_HWSURFACE|SDL_DOUBLEBUF);
 	if ( !screen )
 	{
-		std::cout << "Unable to set 640x480 video: " << SDL_GetError() << std::endl;
+		std::cout << "Unable to set " << width << "x" << height << " video: " << SDL_GetError() << std::endl;
 		return 1;
 	}