Tic or tick? Ducon 07:05, 20 Jul 2005 (UTC)

I think tic. also, see Wikipedia:Tic vs. Wikipedia:Tick -- Jdowland 08:09, 20 Jul 2005 (UTC)
It is called tic internally by the engine. Fraggle 09:09, 20 Jul 2005 (UTC)
OK, I answered because of the comment in the code. The tick is also a flying spider in RoE. ;-) Ducon 09:12, 20 Jul 2005 (UTC)

Tics that aren't 1/35 second?[edit]

This is way over my head, but not Gez's clearly.    Ryan W (talk) 16:00, 25 August 2015 (CDT)

The realtic is always 1/35 of a second because it's "wall clock" time. It's determined by querying the system timer and asking how much time passed since the last time the clock was queried. A gametic is a slice of logic across the entire game engine that would ideally run in that same exact amount of time. This is not always true because for instance the game may have to wait on network input from other nodes, or, it might be running a level with too many monsters for a 486DX4 to keep up with. In that case, the game slows down. In DOS, since there is a vsync latch in place, it will not run faster than it should optimally and does not render extra frames. The Linux Doom code we got on the other hand will draw extra identical frames if it runs tics fast enough to allow it. The system timer under DOS has a very high resolution and is nothing like what Gez is suggesting on there. You can "query" it in nanoseconds if you want AFAIK. Also, the firing of interrupts is controlled by the CPU and is extremely precise, with the amount of latency between one happening and your application getting the response that it happened being the absolute minimum, since under DOS you can hook interrupts with your own functions - and this is what DMX does to interact with the system timer and drive its other system callbacks. --Quasar (talk) 16:44, 25 August 2015 (CDT)
It depends on the timer implementation. The Windows version of ZDoom uses Windows timers which only have millisecond resolution. I assume many other Windows ports have the same quirk, but haven't done any testing. Blzut3 (talk) 17:59, 25 August 2015 (CDT)
Most modern preemptive multitasking OSes have a timeslice of 10ms and can't provide precision better than that through their normal timing APIs. Windows does have a high precision performance counter, though I understand it has some quirks when dealing with SMP. Either way, this article is primarily about the original architecture and how the game was meant to behave by its designers. The limitations of modern OSes might bear mention in their own section but should not displace the primary info. --Quasar (talk) 19:39, 25 August 2015 (CDT)
Enderkevin's using GZDoom, so I told him something that was relevant to his case. --Gez (talk) 10:43, 26 August 2015 (CDT)
Makes sense, thanks. --Quasar (talk) 13:01, 26 August 2015 (CDT)