v0.7 - First preview release

- Updated README
- Fixed small oversight in RenderFrame definition
- Tuned timer for a minor animation speedup

README.md

@@ -2,32 +2,48 @@
 
 ## What is this?
 
-It's my first project ever in graphics programming, and my first screensaver too.
-
-Poggers.
-
-> That's how they say, right?
+It's my first project ever in graphics programming, and my first screensaver too. Whichever is hardest to learn, I'll let you be the judge.
 
 ### Technical details and requirements
 
-The program is implemented in C (standard 17), and uses the Win32 API and Direct3D 11.
+The program is implemented in C (standard 17) and HLSL, and uses the Win32 and Direct3D 11 APIs.
 
-The tools I'm using are Clang as the compiler, and the Windows SDK for all libraries, headers, and other stuff (looking at you, ``nmake``).
+Altough different tools have been used to build this project in previous revisions (Clang, basically), it is currently buildable from the Developer Consoles provided with Visual Studio by using ``nmake``. The Windows SDK version used as of today (2021-05-08) is 10.0.19041.0, some previous versions have proved to be fine too.
 
-Ideally, one can compile the project by using only the SDK, but i'm not too familiar with ``cl``. I guess it's still a completely viable option, if avoiding to install other stuff is desired, and the Microsoft compiler doesn't look scary; it still does a little bit for me.
+> _Finally got over ``cl``, yes._
 
 ## History
 
 I learned to greatly enjoy microtonal music, and one day one of my favorite artists uploaded [this](https://www.youtube.com/watch?v=fCOFjBQ-oKw) video, which coincidentally became one my most loved tracks.
 
 One day, a thought crossed my mind:
 
-> Oh, how cool it would be if my computer showed that crazy geometry stuff when idle...
+> _Oh, how cool it would be if my computer showed that crazy geometry stuff when idle..._
 
 The day after that, I was already deep into MSDN's docs trying to whip up a window. The first commit is the result of roughly two weeks' occasional work.
 
 Hopefully, this will get as close as possible to the video, without blowing up any GPU.
 
+## Lessons learned
+
+I want to dedicate a special section here to _those_ takeaways that may not be clear at all when developing such programs, and nothing seems to concretely help you even with your best efforts.
+
+### _Screensavers don't like files<sup>1</sup>_
+
+To some, this may sound obvious at first. Observe that this is a program that is required _by design_ to execute without a console. Barring debuggers, a very easy choice for getting a trace of what is happening at runtime is to setup a logfile.
+
+A screensaver that uses logfiles will work perfectly on preview, and even up to first install; however, it will fail when it is actually invoked after the idle interval, _and no logs will be created whatsoever_. What may surprise, is that this behaviour can be reproduced by simply importing ``stdio.h`` in the source, without using a single file-related function at all.
+
+The only hint of what happens on crash is in the Windows Event Viewer, which reports a ``STATUS_STACK_BUFFER_OVERRUN`` error; I've learned from the arguably most famous Windows guru that [this error can be infuriatingly misleading](https://devblogs.microsoft.com/oldnewthing/20190108-00/?p=100655).
+
+However, the sneaky catch lies in the consequences for DirectX 11: a popular strategy in building the graphics pipeline involves compiling the shaders' files at runtime by using ``D3DCompileFromFile``. As you might have guessed by now, this is a file operation. _Same problem here_.
+
+The takeaway here is: when you want to build an ``.scr`` file that _actually works_, check carefully for anything that may involve a file, and possibly change it to avoid using the file itself.
+
+Do however keep a logging infrastructure for a separate build scenario, if you feel comfortable with it. I know I did.
+
+<sub><sup>1</sup>: To add to confusion, the [MSDN page dedicated to screensavers](https://docs.microsoft.com/en-us/windows/win32/lwef/screen-saver-library) talks frequently about interacting with an ``.ini`` configuration file. I admit that I still haven't investigated much about that.</sub>
+
 ## Acknowledgements and pointers*
 
 > _Yeah... couldn't resist._
@@ -38,6 +54,8 @@ Other than that, [BraynzarSoft](https://www.braynzarsoft.net/) is a nice complem
 
 And of course, MSDN and StackExchange are regular places to go look for specific stuff. Although, in my opinion, some times MSDN can be your best friend (obviously), and your worst enemy (_not so_ obviously): bring lots of patience.
 
+Many thanks go to [McLytar](https://github.com/mclytar) for testing it consistenlty on his system; it helps a lot to have a different testing environment... with multiple screens, or just better GPUs.
+
 Tech stuff aside, I'm deeply grateful to [Sevish](https://www.youtube.com/channel/UCmq2yMo-lTfC7BQLth_PqOw), the artist behind the inspirational video, and all the guys that are in his Discord corner: now I know that I'll never run out of interesting stuff to learn and new, good music to listen. Thank you, I really mean it.
 
 Special shout-out to YAreyaREdAzE. You know why 😉.

graphics.c

@@ -800,7 +800,7 @@ void applyRotation(void) {
 
 
 // this is the function used to render a single frame
-void CALLBACK RenderFrame() {
+void RenderFrame() {
 
     // animate the shape!
     applyRotation();

main.c

@@ -50,7 +50,7 @@ LRESULT WINAPI ScreenSaverProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lP
         // Get configuration from registry
         // GetConfig();
         // Set a timer for the screen saver window using the redraw rate stored in Regedit.ini
-        uTimer = SetTimer(hWnd, 1, 6, NULL); 
+        uTimer = SetTimer(hWnd, 1, 13, NULL); 
         // Get window info, and start the engines
         CREATESTRUCT* wInfo = (CREATESTRUCT*) lParam;
         InitD3D(hWnd, wInfo->cx, wInfo->cy);