Re: Time accuracy

ML wrote:
PM app, a ball is dropped at moment T at the top of the screen (Y=0).
At moment T+1, Y will be 1. At moment T+2, Y is about 4: accelaration.
For a smooth display the ball also has to be displayed at Y=2 and Y=3,
so it doesn't jump from Y=1 to Y=4 (and next Y=9, Y=16, ...).

What's the preferred way nowadays to delay each step? I don't really need extreme nor time-critical accuracy, "close enough" will do. I did think about a hires timer, but elsewere I read something like "I hope
WarpVision isn't using the hires timer". I don't know if that remark
made sense, I just read it.

Is the hires timer the way to go anyway, or do I need to DosSleep() in
thread 1 and perform some benchmark counting in thread 2, or is there another way to get delays smaller than DosSleep()'s lores delays?



---
Hi,

I have a program called European Juggle which simulates a human juggler very well. This is a PM program, and it doesn't use timers.

A threaded application in OS/2 gets a slice every 32ms, and that makes a pretty smooth display. Use DosSleep(1) to give up the timeslice at each step. You have to work it backwards - calculate where the ball will be next assuming 32 ms have elapsed.

Very occasionally, you can get a short 'hiccup' on a slow PC when a thread overruns.

http://www.manglais.com/download/MAEJ100.ZIP

Peter
.

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