Polish for the Lesson1 source code

Author: Twinklebear

Lesson1/src/main.cpp

@@ -15,61 +15,55 @@ int main(int argc, char** argv){
 		return 1;
 	}
 
-	//First we need to create a window to draw things in
-	SDL_Window *win = nullptr;
-	//Create a window with title "Hello World" at 100, 100 on the screen with w:640 h:480 and show it
-	win = SDL_CreateWindow("Hello World!", 100, 100, 640, 480, SDL_WINDOW_SHOWN);
+	//Now create a window with title "Hello World" at 100, 100 on the screen with w:640 h:480 and show it
+	SDL_Window *win = SDL_CreateWindow("Hello World!", 100, 100, 640, 480, SDL_WINDOW_SHOWN);
 	//Make sure creating our window went ok
 	if (win == nullptr){
 		std::cout << SDL_GetError() << std::endl;
 		return 1;
 	}
 
-	//Now we create our renderer
-	SDL_Renderer *ren = nullptr;
-	//Create a renderer that will draw to window, -1 specifies that we want to load whichever 
+	//Create a renderer that will draw to the window, -1 specifies that we want to load whichever 
 	//video driver supports the flags we're passing
-	//Flags: SDL_RENDERER_ACCELERATED: We want to use hardware accelerated rendering, b/c it rocks!
+	//Flags: SDL_RENDERER_ACCELERATED: We want to use hardware accelerated rendering
 	//SDL_RENDERER_PRESENTVSYNC: We want the renderer's present function (update screen) to be
 	//synchornized with the monitor's refresh rate
-	ren = SDL_CreateRenderer(win, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
+	SDL_Renderer *ren = SDL_CreateRenderer(win, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
 	if (ren == nullptr){
 		std::cout << SDL_GetError() << std::endl;
 		return 1;
 	}
 
-	//SDL 2.0 now uses textures to draw things, but without the SDL_image extension we still
-	//must load the image as a bmp SDL_Surface and the convert it
-	SDL_Surface *bmp = nullptr;
-	bmp = SDL_LoadBMP("../res/Lesson1/hello.bmp");
+	//SDL 2.0 now uses textures to draw things but SDL_LoadBMP returns a surface
+	//this lets us choose when to upload or remove textures from the GPU
+	SDL_Surface *bmp = SDL_LoadBMP("../res/Lesson1/hello.bmp");
 	if (bmp == nullptr){
 		std::cout << SDL_GetError() << std::endl;
 		return 1;
 	}
-	//The texture we'll be drawing
-	SDL_Texture *tex = nullptr;
-	//Now convert it to a texture that is optimized for our renderer
-	tex = SDL_CreateTextureFromSurface(ren, bmp);
-	//Now we no longer need the image so we can free it
+
+	//To use a hardware accelerated texture for rendering we can create one from
+	//the surface we loaded
+	SDL_Texture *tex = SDL_CreateTextureFromSurface(ren, bmp);
+	//We no longer need the surface
 	SDL_FreeSurface(bmp);
 
 	//Now lets draw our image
 	//First clear the renderer
 	SDL_RenderClear(ren);
-	//Now draw the texture
+	//Draw the texture
 	SDL_RenderCopy(ren, tex, NULL, NULL);
 	//Update the screen
 	SDL_RenderPresent(ren);
 
-	//Have the program wait for 2000ms
+	//Have the program wait for 2000ms so we get a chance to see the screen
 	SDL_Delay(2000);
 
-	//Destroy our stuff
+	//Clean up our objects and quit
 	SDL_DestroyTexture(tex);
 	SDL_DestroyRenderer(ren);
 	SDL_DestroyWindow(win);
-
 	SDL_Quit();
 
 	return 0;
-}
+}