Added game module compilation argument

[AndreaCatania]

This is the integration of this feature proposal godotengine/godot-proposals#565

I've already integrated it to see if it could be integrated in a clean way before propose it.

To keep things in order, please discuss here only technical things and improvements of this code, for any other thing please use the feature proposal page.

[Xrayez]

Does this implementation work with both absolute and relative paths supplied to game_module argument? I wasn't sure whether Scons could do that, I assumed that everything needs a relative path.

[Xrayez]

I just tested this PR, works flawlessly for me.

If you plug in some existing C++ module, the only changes you need to do is defining:

void preregister_types();
void register_types();
void unregister_types();

And remove module-specific methods like register_your_specific_module_types() and family. 🙂

Do you think it would be possible to infer module name from game_module path to avoid this?

I'm still not sure whether this is intended to work as a module or as a general-purpose C++ package, so to speak, see my comment at: godotengine/godot-proposals#565 (comment).

[AndreaCatania]

Do you think it would be possible to infer module name from game_module path to avoid this?

This could be possible, but my initial idea were this:

A general-purpose C++ package, so to speak

Were you can plug anything you want, if you want how you desire.

[AndreaCatania]

I'm closing this in favour of this: #36922