How does Doom 3 connect options with cvars?

[PKr]

Long story short I want to add a new option item to the main menu to switch a newly added cvar. The problem is I can't understand how Doom 3 connects cvars with the options menu. I have checked a cstdoom3 code, and for example, you can switch cst_noStaminaDrop cvar there which affects a new menu item called "Stamina Drop" (it switches it to YES/NO). But I can't see a single reference of "cst_noStaminaDrop" being used anywhere outside of functions that affect stamina usage behavior.

 

Can somebody explain to me how Doom 3 draws its options menu, or give me a hint as to what functions to look at?

[GuyMcBrofist]

"guis\mainmenu.gui" Is where you'll find the definition of the main menu including the options menu (talking about vanilla doom 3 here), which you can find in pak000.pk4. There, you'll see some entries that use a "cvar" key to refer to the cvar the menu item changes.

 

Doom 3 comes with a GUI editor, which you can use by typing "editGUIs" in the console. Not sure how useful you'll find it. I can get it to open GUIs and browse the elements, but just get a blank window where it's supposed to visually show the gui (edit: turns out having r_multisampling set to non-zero was causing this).

 

I can't speak much for cstdoom3, it's packaged a bit strangely and I didn't bother to install it.

Edited February 23, 2023 by GuyMcBrofist

[PKr]

Thanks a lot! Wouldn't have figured this out without your help.

Edited February 22, 2023 by PKr