1. help: flickering animations
i'm trying to do some 3D and stuff which is going great except for a
few things (i'm going to break this up into 2 messages because they
deal with different things)... anyway about my flickering
it seems to me that i'm already starting to erase what i've just
drawn when the screen refreshes, so i'm left sometimes with half a
cube on screen, sometimes with the whole cube, sometimes with no cube
at all...
what i'm wondering is...how can wait until the screen refreshes
before i start erasing?? do i have to know the refresh rate of the
screen and then use a timer?? if so how do i figure out the refresh
rate (i'm designing this so i can be used in any screen mode)
. o O Mike Burrell O o .
. o O burrellm at geocities.com O o .
. o O mikpos.base.org O o .
2. Re: help: flickering animations
> it seems to me that i'm already starting to erase what i've just
> drawn when the screen refreshes, so i'm left sometimes with half a
> cube on screen, sometimes with the whole cube, sometimes with no cube
> at all...
>
> what i'm wondering is...how can wait until the screen refreshes
> before i start erasing?? do i have to know the refresh rate of the
> screen and then use a timer?? if so how do i figure out the refresh
> rate (i'm designing this so i can be used in any screen mode)
You can do one of two things. Wait for the retrace (which happens at 70 Hz,
but I might be wrong) and blast to the screen. You only have about 70 ms to
do this before the image is displayed on the screen. There was some code
posted to the list server a while back
to take care of this.
The second method is to write to a virtual screen, then copy to the video
display. This however might not work well in all modes (Due to the VGA
hardware limits)
Hope this helps..
Greg Harris
blackdog at cdc.net
