Capping the framerate? (not noob)

SDL Development
1

Hello, ladies and gentlemen of the SDL list!

Okay. You all know what Lua is, right? If not, ignore this thread.

Here’s my question. I’ve got a Lua script that will call SDL functions.
Well, I need to cap the framerate to 60FPS without the user having to
do anything to the script.

I thought of making the user have a ‘main loop’ function in Lua that
will execute in my program’s main loop, which will do the capping. But I
can’t do that. Don’t ask why, I’ve got my reasons.

So, anything like…

SDL_CapFramerate(60);

… that I can put in main() and will affect the whole program?

Yes? No? Didn’t think so. So what’s the closest approach?

Thanks in advance for any help provided!

(P.S., I know Allegro can do this, but it doesn’t support alpha
transparency which also is an underlined need.)

2

Hello !

… that I can put in main() and will affect the whole program?

Yes? No? Didn’t think so. So what’s the closest approach?

Thanks in advance for any help provided!

?!?!?!

Sorry i don’t see where the problem is.
I never used Lua, but i can image 3 cases :

  1. You can call SDL functions directly from Lua.
    Then do something like in Lua of course :

At the start of your main loop :

Uint32 startticks;
startticks = SDL_GetTicks ();

At the end :

Uint32 endticks = startticks + (1000/60);
SDL_Delay (therestofyourframetime);

  1. You can call C functions from Lua :

Then put the stuff from 1 into two C functions.

  1. You can only modify variables and arrays
    from Lua, then put it into the main loop of your c code
    at the start and end of it.

It affects all your code, but this is something
you normally want, when you have a frame limiter.

CU