[SDL] Delta time?

[Justin Coleman]

Multiply your framerate (60/sec?) by each of those numbers to get the
total change per second, then multiply the per-second value by however
much (fractional seconds) time between frames. The 1% deceleration may
need to be tweaked, since it's dependent on the current speed and not
a fixed value.

On 10/12/07, L-28C <kixdemp at gmail.com> wrote:
> Hello people of SDL!
>
> I've been capping the framerate in my games the last few times, but I
> want to give delta time a try... Here's the code I have modified to work
> with DT:
>
> -----------------------
>         oldTime = SDL_GetTicks();
>
>         while (1)
>         {
>                 newTime = SDL_GetTicks();
>                 delta = newTime - oldTime;
>
>                 /* Update control status */
>                 handleControls(controls);
>
>                 /* TODO: Pause, not exit */
>                 if (controls[K_PAUSE]) exit(0);
>
>                 /* Process game logic */
>                 doLogic(delta);
>
>                 /* Render our scene */
>                 renderBackground();
>                 render(0);
>
>                 /* So we don't use 100% CPU */
>                 SDL_Delay(1);
>
>                 oldTime = newTime;
>         }
> -----------------------
>
> In doLogic(), what I had done while capping FPS was add 0.05f to the
> ball's speed (acceleration) and multiply by 0.99f (deceleration).
>
> But how would I modify those values to work with my delta?
>
> Thanks!
>
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