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How do you control time on the iPhone? - Printable Version

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How do you control time on the iPhone? - riruilo - Dec 28, 2008 01:05 PM

Hi friends!

How do you control time on the iPhone?
Is there any like SDL_GetTicks() to get miliseconds since app was launched?

I need something like that to control my animations and movements.
Any suggestion?

BTW: Better if I can use it through CPP.

Thanks a lot, I appreciate a lot your help and time.


How do you control time on the iPhone? - AnotherJake - Dec 28, 2008 03:04 PM

Skorche and I accidentally posted some mach timing code in this other thread recently: http://www.idevgames.com/forum/showthread.php?t=16298


How do you control time on the iPhone? - AndyKorth - Dec 28, 2008 03:47 PM

The iPhone can control time? Finally I can go back and stop myself from dating that one girl.

Sorry... couldn't help it Rasp


How do you control time on the iPhone? - riruilo - Dec 28, 2008 03:58 PM

AnotherJake Wrote:Skorche and I accidentally posted some mach timing code in this other thread recently: http://www.idevgames.com/forum/showthread.php?t=16298

I already saw that post. Perhaps nanoseconds is too much accurate, I only need miliseconds.

Did you use that method on a game? Do you think it is suitable for games? I mean, does that method add overhead? (I have no idea about this).

Thanks a lot for your help.


How do you control time on the iPhone? - AnotherJake - Dec 28, 2008 04:23 PM

Accuracy being in nanoseconds vs. milliseconds has little to do with performance or overhead. We modify it so it returns time in seconds as a double precision float. Yes it works great for games, which is why we use it.


How do you control time on the iPhone? - Skorche - Dec 28, 2008 08:14 PM

Yeah, the extra precision certainly isn't going to break anything, and it's not going to be slower really.

As Jake said, it returns the time as a double in seconds, so it's easy to work with.


How do you control time on the iPhone? - riruilo - Dec 29, 2008 01:54 AM

Thanks a lot for replies.

As I just need miliseconds, What do you think (AnotherJake) if I modify your code with this?

miliseconds = (double)nanos*1.0e-6;
return miliseconds;

Thanks.


How do you control time on the iPhone? - AnotherJake - Dec 29, 2008 08:13 AM

Yes, seems like that should do the trick. Need to reduce nanos by three orders of magnitude less than you would for seconds to get milliseconds. Accordingly, microseconds would be nanos * 1.0e-3