Re: RELEASE: Day of Survival v0.91 [Updated 11/27/2014]

Posted by kodabar on Dec 09, 2014; 4:39am
URL: http://kodabar-dayz-daizy-single-player-forum.163.s1.nabble.com/RELEASE-Day-of-Survival-v0-91-Updated-11-27-2014-tp16267p17570.html

It's difficult to say without some more details of your situation. I'd be particularly interested in what processor and video card you have.

There are lots of reasons why things might lag. One of the ones I find most commonly is:

The ArmA games have an unusual way of handling graphics. Most games get the graphics card to do most of the work, using the processor only for things like the location of the player, tracking of shots, etc. The ArmA games takes the opposite approach and get the processor to do everything, barely touching the graphics card at all.

Often in an ArmA game, the processor is running nearly maxed out, so the slightest additional load can cause stalling. When playing DayZ, the server handles a lot of stuff like player tracking. In creating a single player version, there is no server to help with the donkey work, so there's a bunch of extra load on your CPU from simulating all the server stuff. And there's also the extra stuff like running the AI players and any extra scripting that the mod author has added.

If the author has added a bunch of stuff, it really starts eating into the processor. This can get worse over time as the zombie bodies and dead players pile up - by default the game doesn't despawn them. So unless an author adds some cleanup routines, the processor ends up having to track hundreds of corpses (and their inventories). Even AI units add to the burden. Mostly they're not spawned until you get within a certain radius of them. If there isn't a cleanup routine to despawn them, then a walk across the map can cause hundreds of AI units to spawn, even if you don't see them.

Sooner or later, all this can really tell on your processor. Once enough work is piled on it, the processor starts to lag behind (this is why you see some people on here reporting that they can get it to run, but don't see zombies or AI units). Because the ArmA engine lumps a lot of the graphics load onto the processor, frame rate can really suffer. All this whilst the graphics card is relatively untouched.

There's also the fun of occlusion culling. In most games, there's a quick programming routine running to determine what you can see. Without occlusion culling the game would render everything - so if you're hiding behind a rock, the game engine would still draw all the stuff on the other side of the rock; stuff you can't see and the engine is going to draw over with rock textures. Occlusion culling does a very quick calculation in order to work out what ought to be visible and then stops the engine from wasting time rendering that stuff.

Before ArmA 3, there was no occlusion culling in Bohemia's game engine. So if you're facing a brick wall inside a bathroom in Cherno, the engine will render everything within the view distance, even though it won't be able to draw it on the screen. That's why the frame rate drops in large towns - the game operates as though everything is made of glass. In the version of the game engine used by ArmA 3, there is limited (it's nowhere near what some game like Call of Duty does) occlusion culling, helping reduce the load and making the game run smoother.

So... it's entirely possible that you can have a computer that runs ArmA 3 beautifully, but struggles with some single player DayZ mods under the ArmA 2 engine. When you're running ArmA 3, you're probably playing on a server and you're using a more advanced version of the game engine that includes occlusion. The processor is king when it comes to running these missions.