Adapt build.zig to redesigned raylib build features config system

[Wertual08]

Hello, It`s my first time submitting the PR, so, sorry to waste you time if it does not worth to be merged...

Problem:
Since commit 5361265 raylib config system was redesigned, and current build.zig stopped working at all by providing empty defines. Furthermore, I believe that with new config system there is no need to parse config.h to extract default defines.

Solution:
I removed default config.h parsing and replaced passing -D flags with appropriate addCMacro build call.
Overriding default values can now be done by users as in example below instead of passing options.config which seemed to me like a crutch O_o

const raylib_library = raylib_dependency.artifact("raylib");
raylib_library.root_module.sanitize_c = .off;
raylib_library.root_module.sanitize_thread = false;
raylib_library.root_module.addCMacro("SUPPORT_MOUSE_GESTURES", "0");

I`ve tested building of my projects on Windows 11 and latest Linux arch.

Thanks you very much in advance for your time. Hope this will be helpful...

[felipeasimos]

Hi @Wertual08, I ended up also opening a PR that ends up tackling the same issue in parsing config.h. I ended up taking another approach though, so I guess is up to raysan to choose which way we should go. Either way, I just want to let you know that this solution seems to result in a black screen when running examples, using the latest zig version (0.16.0-dev.2860+9c5460316).

[felipeasimos]

I was taking a look at it, and the black screen in zig master is probably because not all macros are included and also don't have their default values included in the try raylib_flags_arr.append(b.allocator, "-DMACRO"); statements.

As far as I understand, not using a value was compatible with the previous config system where only defined(MACRO) was used, so now we need to also pass the value, correct? (ex.: -DMACRO=1)

[Wertual08]

Yeah, but new config.h already provides meaningfull default values, so why parse it to override them with the same ones?

[felipeasimos]

I am not entirely familiar with the build process, so I could be missing something obvious, but I feel like like the default values are not being propagated the way you think they are? For example, I managed to find exactly what makes zig build core_basic_window result in a black screen. Just add this to line 225:

try raylib_flags_arr.append(b.allocator, "-DSUPPORT_CUSTOM_FRAME_CONTROL=0");

If you add this, the example now works! Using =1 or leaving it empty doesn't.

I think your approach is good, I just think we need to validate with zig master.

[Wertual08]

Thanks, I`ll check this out today.

[felipeasimos]

Actually, I am sorry, I ended up using the master branch from your fork. The example works correctly! I'll close my PR

[Wertual08]

Oh, no problem! Thanks you very much for testing my PR. I was surprised, because I tried it on two systems, but now we came to agreement. Thanks for your time!

[raysan5]

@Wertual08 @felipeasimos thanks for the improvement and further reviews!