dead and exploding vehicles really loud

[Tankbuster 1714]

Guys, I hope someone can help with this. One of my secondary missions has players interdicting an enemy AI convoy. Getting the convoy to drive as such was a mission in itself. Now I need help on another aspect.

 

When the convoy vehicles are found and killed, if their wrecks are close to one another, the (I think they are called) secondary explosions are sometimes REALLY loud and destructive. One explosion seems to set off another in a nearby vehicle and there is a domino effect. The video doesn't really do it justice, these explosions are sometimes so loud that my headphones can't handle it and the sounds are clipped.

 

The first few times this has happened the convoy was Tempests so I suspected them. The convoy composition is random and this morning it was a bunch of the MB 4x4s, little indie vans and small trucks, and the video shows the same problem. I've removed all the ammo, weapon and fuel cargo in case it was the game simulating cookoffs, but that has made no difference.

It is probably not relevant, but in tests where I've spawned the convoy mission using debug tools, the issue hasn't occurred. In other words, it happens on missions that have been running for some time.

This also may not be relevant, though I suspect it is - other features of the mission break down when this behaviour is observed. There is a simple moving marker script that puts a marker on one of the players respawn vehicles - that stops updating and a server-side spawned script that services vehicles when they get close to a vehicle depot object also just stops working. No errors - just stops. When the convoy mission ends by me manually ending the script, these features return to normal.

 

Any help would be really appreciated. Having worked so hard to get the convoy sort of working, I'd be gutted if this problem forced me to remove this secondary mission from the overall mission.

[johnnyboy 3582]

That is very strange.  Do you have any mods running?

 

If you want to prevent secondary explosions, you could try an onKilled eventhandler on the vehicles that sleeps a few seconds then sets enableSimulation to false.  Worth a try methinks.  Good luck.

[Tankbuster 1714]

Only a couple of client side mods. Enhanced movement, urban rappelling, that sort of thing. The server side is totally vanilla.

I was thinking of stopping the simulation on the wrecks, but not tried it yet. I thought that removing all the ammunition cargo would be the fix, but it hasn't made any difference. Hopefully fiddling with the sim will be next. I can't think of what to try after that.

[whiztler 135]

I remember from the old days with insurgency on Arma1 and 2 that when server load was high the explosions (blowing up the cache) would get out of hand (lots and amplified). Perhaps monitor server FPS and check which scrips are running at time of the explosions.

[Tankbuster 1714]

10 hours ago, whiztler said:

I remember from the old days with insurgency on Arma1 and 2 that when server load was high the explosions (blowing up the cache) would get out of hand (lots and amplified). Perhaps monitor server FPS and check which scrips are running at time of the explosions.

Yes, I checked, the server was in the high 40s the three times we've seen this.

[phronk 861]

Out of curiosity, do these vehicles have any eventHandlers attached to them? Or is there an EntityKilled missionEventHandler? I doubt it would be related but ya never know. I think it's an engine issue amplified by script problems, something to do with JIP, I'd say.

 

When a playSound is played multiple times at the same time, it gets louder. With that said, the same functionality probably applies to other sounds like vehicles exploding. Maybe a soundmod issue or the wonkiness of JIP is causing the explosion effect to play X amount of times, X being the number of players that've connected. IDK. I've had this issue years ago on public server missions but haven't had it in a good while. Never truly figured out the fix aside from server resets.

[Tankbuster 1714]

2 hours ago, phronk said:

Out of curiosity, do these vehicles have any eventHandlers attached to them? Or is there an EntityKilled missionEventHandler? I doubt it would be related but ya never know. I think it's an engine issue amplified by script problems, something to do with JIP, I'd say.

 

When a playSound is played multiple times at the same time, it gets louder. With that said, the same functionality probably applies to other sounds like vehicles exploding. Maybe a soundmod issue or the wonkiness of JIP is causing the explosion effect to play X amount of times, X being the number of players that've connected. IDK. I've had this issue years ago on public server missions but haven't had it in a good while. Never truly figured out the fix aside from server resets.

There is a handledamage on each of the vehicles that negate collision damage, to stop the convoy vecs getting destroyed by crashing into each other, or wall/buildings. There are no entitykilled MEHs

_x addEventHandler ["HandleDamage", {if (isNull (_this # 3)) then { 0; } else { _this # 2; }; }];

I didn't know playSound 'stacks', that does sound like what is happening. You mention sound mods, there are none in use. Reference JIP, the last time this was observed was the same session I captured the above video, there was a single player connected before the convoy mission spawned. As I had previously said I hoped I'd cured the issue by removing Tempests from the array that supplies what is spawned, he contacted me to say we had the little indi trucks and they were making the same crazy noises. I joined after he observed this and I joined the server and made the video.

 

I just want to reiterate a few things I said earlier, not because I'm dismissing your theory, far from it, but they are among the weirder things Iv seen in connection with this issue.

First, the apparent stall of 2 very simple scripts within the mission, a moving marker that shows the pos of one of the respawn vehicles and the vehicle service script. There may be other mission scripted features that stop working, I don't know. I do know that when these loud vehicles are despawned, all of these scripted features return to normal. Also, this doesnt happen in testbed missions. It only seems to happen on servers that have been running for some time, more than a day or two (this is a persistent battlefield mission).

[phronk 861]

A heavy script in the background may be filling up the scheduler, which is what is causing other scripts to run slower or pause. Usually bad while{true}do loops can cause this. As for the sounds issue, I had a bug where setting damage to all trees in Livonia would freeze/crash the game with really loud tree falling effects (Plays a tree falling sound per tree which destroyed the game)

 

I doubt the handleDamage eventHandler had anything to do with it, but it may be failing due to how slow everything began to run? Also doubtful since you said server FPS was around 40 so most likely find the code/script thats choking (Review server and client RPT logs) and should fix the problem.

[Tankbuster 1714]

18 minutes ago, phronk said:

A heavy script in the background may be filling up the scheduler, which is what is causing other scripts to run slower or pause. Usually bad while{true}do loops can cause this. As for the sounds issue, I had a bug where setting damage to all trees in Livonia would freeze/crash the game with really loud tree falling effects (Plays a tree falling sound per tree which destroyed the game)

 

I doubt the handleDamage eventHandler had anything to do with it, but it may be failing due to how slow everything began to run? Also doubtful since you said server FPS was around 40 so most likely find the code/script thats choking (Review server and client RPT logs) and should fix the problem.

There's nothing out of the ordinary in any RPT. I'll go through the script with a fine-toothed comb and report back. Thank you.

[Tankbuster 1714]

Some progress. There was a number of threads spawned by this particular mission, mostly to help the AI drive in convoy,  but I carefully checked the impact of every one. The scheduler wasn't busy.

What I have found is that the (loud secondary explosions) effect is more pronounced when there are other dead vehicles near by - it seems that the secondary explosions of one vehicle can set off more in another vehicle nearby.

Anyway, it happened again during a different mission so we can rule out the sheduler being overworked. What I have noticed is that disabling the simulation of the objects stops the secondary explosion behaviour, so I think that's the best way to fix this.