ZDoom 2.0.47i still loses sync a bit

Wed Aug 20, 2003 5:33 pm

We did a solid play-through of Ultra-Violence DooM II, and the netcode seems to be holding up much better.

However, the culprit for going out-of-sync is still those damned Pain Elementals (if you don't kill them fast enough).

Other than that, it looks perfect.

Maybe if they were to have a short timer before each skull?

Wed Aug 20, 2003 6:42 pm

I didn't know about the Pain Elementals. I'll take a look at them when I have time.

Wed Aug 20, 2003 9:37 pm

Actually, when I got 47i I tried to do something I've been wanting to do for a LONG time, and that's co-op Hexen. Unfortunately we had a hell of a time doing it. We never had problems with desyncs when we played Doom or ZooM but Hexen liked to desync every two minutes it seems.

I still don't know of the main problem, but it happened most often in the second hub. We could usually get through the first hub okay but in the second hub it usually didn't take long before it blasted us.

Thu Aug 21, 2003 11:03 pm

Same here.

To help Randy out a bit, I think it has something to do with the wizard ice power, it seems like it only de-syncs often when you start making monster ice cubes.

Maybe making frozen monsters unpushable (until you shatter them), and doing something about the pieces when it shatters would help (seems to be a little too many).

I'm not sure what part of the power it syncs, but obviously it shouldn't be synchronizing those ice chunks (if it does).

Haven't seen Heretic de-sync yet, though.

Sun Aug 24, 2003 2:40 am

More on the Hexen de-syncing: pots you smash seem to do it too.

Edit: And certain doors. It looks like the Hexen scripting may be at fault?

Mon Aug 25, 2003 1:53 pm

Update: The Hexen scripting is definitely at fault -- we lost sync on a LAN more than once.

Tue Aug 26, 2003 2:58 pm

Actually, I think it's probably because you're able to push things around during the predicted movements as well as the real movements. That's what it sounds like. I haven't checked the source yet to see if that's actually possible.

Tue Oct 14, 2003 3:01 pm

My hunch about pushable things turned out to be correct, so that's fixed now.

The problem with Pain Elementals is much more elusive. I think I am on the right track to figuring it out, but I don't yet know how much more testing will be required before I fully understand why they desync. If the problem turns out to be what it's starting to look like, fixing it might also fix other rare desyncs.

Wed Oct 15, 2003 1:23 pm

The Pain Elemental problem seems to be solved now. Movement prediction did not preserve the ordering of blockmap links. I'm not sure why this was most noticable with the Pain Elemental, but I imagine the bug caused other less reproducable desyncs too.

I am glad to be able to finally mark this as fixed.