Refresh rate is disgruntling my timing

SDL Development
1

i’m trying to set my game up to run at 30fps, simply enough
by using GetTicks and Delay.

i’m sure this has been discussed, but i couldn’t find anything
searching the archives.

my game can only run in certain fps “steps”. it runs fine at
24, but little tweaks dont do anything until it jumps to 32.
then the same thing until it jumps to the next speed.

i assume this has all to do with the vertical refresh of the
monitor. the game is using a single-buffer and is currently
just calling UpdateRect a couple times per frame.

is there a way to specify SDL to not wait for the refresh?
would i be better grouping my 5-10 UpdateRect calls into
1 UpdateRects. (none of the rects overlap)

anyways, this is currently happening on winnt, therefore
using the wingdi driver.

thanks for tips… i’m looking for the best way to get my
gameloop running at a specific FPS.

2

my game can only run in certain fps “steps”. it runs fine at
24, but little tweaks dont do anything until it jumps to 32.
then the same thing until it jumps to the next speed.

i assume this has all to do with the vertical refresh of the
monitor. the game is using a single-buffer and is currently
just calling UpdateRect a couple times per frame.

anyways, this is currently happening on winnt, therefore
using the wingdi driver.

The GDI driver doesn’t wait for vertical refresh.

See ya!
-Sam Lantinga, Lead Programmer, Loki Entertainment Software