What are the benefits of SDL_bool

I’m just a little miffed.
In SDL3: I noticed as I was setting up toggling between fullscreen that SDL_SetWindowFullscreen() now takes a SDL_bool as an argument.

My question is, why? If it took the original Uint32 flag I could xor it to toggle the flag.
If it took a regular bool then I could say fullscreenFlag != fullscreenFlag;

But SDL_TRUE and SDL_FALSE are either preprocessor-macro defined or an enum depending on if you’re on an ARM or X86_64 system.
In order to toggle, I have to implement a if/else or a ternary statement which takes extra lines, extra thought, and extra CPU processing time. You are also forced to use SDL_TRUE or SDL_FALSE in order to set the values.

Why is SDL_bool even a thing?
Why is it not a typedef or some other translation of traditional bool?
Why would it be chosen as an argument type for SDL_SetWindowFullscreen()? → the source uses a ternary to translate the SDL_bool argument back into the Uint32 flag just two lines into the function definition.

I’m only seeing the cons right now, and I know I’m being unfair. I know it’s ridiculous to worry over 6-12 extra CPU cycles, or the slight inconvenience… but why is it there to begin with?

What are the benefits of SDL_bool?

Edit: All of the above is now obsolete, Please see below.

I also don’t like SDL_bool but to be fair, SDL is a C library and it seems like you can use SDL_bool essentially like the regular bool type in C because integers are implicitly convertable to enum types so you can write things like:

SDL_bool fullscreenFlag = SDL_TRUE;
fullscreenFlag = !fullscreenFlag;

If you include <stdbool.h> you can replace SDL_TRUE with true (assuming you use C99 or later).

You can even pass a normal “bool” directly as argument to SDL_SetWindowFullscreen if you want.

In C++ it becomes less convenient because there is no implicit conversion to enum types so we have to use casts.

SDL_bool fullscreenFlag = SDL_bool(true);
fullscreenFlag = SDL_bool(!fullscreenFlag);
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As a C++ user I did not know that SDL_bool is not quite so annoying in pure C language.

Looking to the C++ portion of your response: That is definitely faster performance-wise than going through a whole if/else or ternary.

Great advice and explanation all around. Thank you Peter87!

I do still hope future SDL3 function development avoids using SDL_bool for other function arguments, but at least I have a strategy if it does creep its way in.

I must say that SDL is amazing, thank you all developers. This really is such a tiny issue, and it’s the only one I’ve had all week. You guys are awesome!

One other thing to keep in mind is that SDL itself is written for C89, where stdbool.h isn’t available.


This is fixed for SDL3, thanks!

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I tried to respond several times, but you left me wordless.
Thank you Slouken et al.

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You’re very welcome!