Execution based on time instead of frame rate

[mind 60]

Dear BI community,

Fellow brothers-in-script! Your wisdom and intelligence is needed, to cast light on subject below.

Consider following code:

_func = {
for "_i" from 0 to 100 do {
	_t1 = diag_tickTime;
		sleep 0.2;
	_t2 = diag_tickTime;
	systemChat str (_t2 - _t1);
};
};
[] spawn _func;

This code indicates (by writing to system chat), the real time took by sleep command to finish.

If you would be so kind to try it out, you would notice HUGE differences between results,

This spikes can be seen when FPS changes dramatically. from 50 to 20 for example.

While FPS is stable, sleep working almost ideal.

it sometimes may take slightly less time and sometimes 5x more time to finish.

This is of course completely understandable, because of scheduled script execution mechanism arma have.

Now comes the question.

How one would get execution of script with PRECISE timing, from scheduled environment? Without any relation to current FPS.

I tried monitoring diag_tickTime, and fire event regularly with this kind of code

_func = {
for "_i" from 0 to 100 do {
	_time = diag_tickTime;
	_wait = 1;
	_t1 = diag_tickTime;
	waitUntil {diag_tickTime > (_time + _wait)};
	_t2 = diag_tickTime;
	systemChat str (_t2 - _t1);
};
};
[] spawn _func;

And it has slightly better results. But still way not perfect.

Peace. mind out.

P.S. I noticed some clues from KK blog regarding execFSM, does anyone know if it has any relation to topic?

Edited October 31, 2014 by mind

[dreadedentity 278]

What are you trying to do? Are you trying to synchronize script execution between all clients? Are you trying to run a script exactly at a certain time? (ie. when client has played for 5 mins run "myScript.sqf")

The easiest/best way I can think to do this is to addpublicVariableEventHandler to all clients, then publicVariable your variable from server. Near perfect sync

[mind 60]

Thank you for your answer DreadedEntity,

Such thing might be used in many ways. I am talking about, incorrect (IMHO) execution of sleep commands, where you are unable to offset frame rate impact on execution speed. And as result sleep command takes longer than it should.

Regarding eventHandlers, they of course useful, but not always. For example, i am making free roam camera where i camSetPos every 0.1 secs. eventHandler can’t make sure camSetPos will execute exactly once per 0.1 sec.

P.S. In unity there is following method "time.deltaTime" to offset FPS impact. Is there anything like that in ARMA, maybe some nasty workaround...

Edited November 2, 2014 by mind
added P.S.