Smoke, Dust, Arty, and You

[Treeburst155]

OK, I'm convinced that the state of LOS at the beginning of the turn in which the arty is going to begin falling is the deciding factor.

Here's the new bug definition. See if you can get contrary results.

If a spotter's LOS is blocked by dust or smoke at the very beginning of the turn in which the spotting rounds are due to fall, the strike will be treated as a blind strike. As long as any smoke or dust clears before this point in time, or appears after this point in time, the strike will be on-target.

Only this single instant in time, at the very beginning of the turn, is important. You either have LOS at this moment, or you don't. If not, you get a bad strike.

Ok fellas, try to find exceptions to this new definition. I will try too.

Treeburst155 out.

[ March 27, 2004, 02:02 PM: Message edited by: Treeburst155 ]

[Treeburst155]

I just got a strike with NO spotting rounds that landed on target!! LOS was blocked througout the delay period. So, blind strikes will occasionally be on-target; BUT, the first salvo will be a full salvo, without spotting rounds. No spotting rounds, no refutation of the new bug definition. This is what has happened in some of our test runs, I think.

[Holman]

Interesting! Does this go for smoke, or just dust? If smoke does it too, does this consideration also apply to CMBB?

I still wonder if all this may be a limitation of the engine as it stands, rather than a new and fixable bug.

[Treeburst155]

Smoke messes with arty too. I don't think CMBB behaves this way. I would have griped about it long ago if it did. I still play a lot of CMBB, and I haven't noticed this arty behaviour. When they added dust, they affected smoke too, I think. I suppose I should test CMBB to make sure; but I think I would have run into this behaviour long ago if it were in CMBB too.

Treeburst155 out.

[Treeburst155]

I've been accurately predicting which strikes will be on-target (with 81mm, 105mm, 155mm), and which ones will not, simply by the LOS situation during the orders phase just prior to the firing of the first round. I've been unable to disprove my latest definition of the bug. I think we've pinned it down rather well now. Everyone's results in this thread have been explained.

There is an interesting thing related to spotting rounds that I hesitate to bring up because it does not refute the new bug definition, or have anything really to do with the bug. It's just interesting spotting round behaviour.

With the 155mm, I noticed that even bad strikes will frequently have a spotting round fired some 55 seconds before the first full salvo. The strike will nevertheless be off-target as determined by the obstructed LOS at the beginning of the turn in which these spotting round(s) were fired. Perhaps these strikes are adjustable in the next orders phase?

Unless someone reports results that contradict the latest definition of this bug, I'm done testing. Here it is one more time:

If a spotter's LOS is blocked by dust or smoke at the very beginning of the turn in which the spotting rounds are due to fall, the strike will be treated as a blind strike. As long as any smoke or dust clears before this point in time, or appears after this point in time, the strike will be on-target.

EDIT: Remember, it is possible for blind strikes to be on target. Except maybe in the case of the 155mm, you will not get spotting rounds with these on-target blind strikes. I guesstimate about 1 in 6 blind strikes will hit the target.

Treeburst155 out.

[ March 27, 2004, 12:45 AM: Message edited by: Treeburst155 ]

[Holman]

I'm playing Devil's Advocate here: is there anything actually wrong (i.e. unrealistic) with this behavior? Is it actually a bug?

Since CM processes turns in 1-minute chunks of time, perhaps the beginning of each minute/turn is the only time when the game checks to see if the FO can spot the target. (Maybe it's too processor-intensive for the game to check for good LOS each second?) If the FO can't see the target when the game checks for LOS at the start of the crucial turn, then the strike is considered to be a bad one until it is replotted. But might not this be a reasonable approximation of how WW2 spotting worked?

Obviously this makes spotting and readjusting more work-intensive, since you might have to re-plot several times to bring rounds on target. But did real FOs have it any easier in WW2? Could they count on accurate strikes as often as we would be able to if this "bug" were squashed?

I noted in my tests that adjusting fire (green line) brought the rounds closer to the target each time. I tended to run out of ammo before I could adjust more than twice, but I wonder if I might have brought the rounds onto the target accurately after three or four green-line adjustments. (This is something to test for.)

Maybe the need to re-plot (blue line) "obscured LOS" artillery strikes instead of just adjusting them (green line) accurately reflects the workload of an FO who can't accurately report on the relation of the spotting rounds to his target.

Another note: testing seemed to suggest that smaller-caliber FOs didn't experience the "bug" as larger-caliber FOs did. Since small caliber artillery is usually more local to the FO (being battalion-level rather than, say, Division-level), perhaps this represents the greater responsiveness of working with one's own unit's organic assets. ???

[Treeburst155]

Smaller caliber FOs still exhibit the bug. They are just less susceptible due to the shorter delay period. In fact, an 81mm can be delivering rounds within the first minute. When this happens, there is no possibility of smoke/dust messing up the strike because the beginning of the turn in which the rounds were to drop had clear LOS. The targetting turn is also the first turn of impact.

Is this behaviour a bug? I guess that depends on whether or not it is intended behaviour. If I had designed the game, it would be a bug. BFC may see things differently.

Let's look at a typical situation. A 155mm spotter has LOS to a target point. He calls in the strike and waits. At some point his LOS is obstructed for, say 30 seconds. This 30 second LOS block just so happens to begin 25 seconds before the end of a turn. It will end 45 seconds before the spotting rounds are due to hit. So, LOS will be clear when the spotting rounds are due. However, because the blockage spanned a turn, there will be no spotting rounds, and the strike will likely be off target. Had the 30 second blockage begun just a few seconds earlier, so as not to span turns, the strike would be good.

To me this is undesireable behaviour; but it's not as bad as I first thought. Spoiled strikes can be discovered and cancelled in the orders phase. If LOS is blocked in the orders phase, and the timer shows that rounds will be dropping this turn, you cancel the strike. Blind strikes due to dust or smoke can be avoided EVERY time if the player pays attention.

It is nice to know these bad strikes are easily caught; but the characteristic still makes arty VERY difficult to use in dry scenarios. Still, it may not be a bug in BFC's eyes.

I really don't care if they fix it or not because I understand the behaviour now. Never again will an "observed" strike land on one of my own platoons. I know how to prevent it now. Bug or not, it's no longer going to hurt me or my cyber-troopers.

Treeburst155 out.

[John Kettler]

Martyr,

The way the process is supposed to work in real life is that the FO informs the Fire Direction Center (FDC) of the target, target coordinates, orientation, etc., information then used by the FDC, assuming fire support is actually available,

to generate azimuths, elevations, shell and fuze selections, not to mention propellant charge increments, for the firing unit or units. When all the crunching's done and the artillery or mortars are ready to fire, the FO gets a quick call to notify him that the spotting round's coming. Said round's arrival is either sensed, in which case the FO passes corrections as up (add range), down (decrease range) and left or right if the range is correct but the azimuth is off, or the spotting round is called "Lost!" at which point another spotting round is fired. Having made the aimpoint corrections to the eventually sensed spotting round, depending on the tactical situation, the FO may or may not go right to FFE without waiting for an additional spotting round/rounds The decision to go to FFE rests solely with the FO.

What people are upset about, in part, is that the dust problem is not only arbitrarily depriving them of control and endangering their troops, but the way the fire procedure is implemented, they're being forced to burn pricey, scarce artillery support in a wholly ahistorical manner. You shouldn't be burning through your ammo stocks wholesale while adjusting your fire mission. A handful of rounds expended in adjustment? Fine. But to have a minute or more of fire wasted because a seeming logic glitch forces a player into premature and generally off target FFE is not fine.

As for FO workload, watching for the arrival of the spotting round is the FO's task, and the swift provision to the FDC of any necessary corrections is vital in order for effective fire to be delivered on the target--the FO's real job. Unless the FO's ducking and dodging under fire, what is he doing when the spotting round's inbound? Rather doubt he's reading one of those Army issue paperback novels!

Regards,

John Kettler

[GreenAsJade]

It feels like a bug to me.

I think it's been well defined.

It causes players to have to check their FO LOS every darn turn - if that's not a bug, it's a darn nuisance.

I think it's time for BFC to comment.

GaJ.

[Redwolf]

Going FFE when the spotter cannot establish that the strike will be on target via spotting rounds is a bug in itself, independently of why spotting rounds were off or missing.

[Steve McClaire]

I suspect that the current definition of the problem is correct - probably the game checks LOS from the spotter at the begining of the turn because that is when all the crunching is done to generate the events that make up the movie for that turn.

I don't think BFC will consider this a bug, in the sense that what happens now is probably the intended behavior. Annoying for the player, perhaps, but given the way the game works it may be the only reasonable way to deal with the situation.

If the spotter's LOS ends up blocked when the game is trying to resolve the spotting rounds and generate the turn's movie, what should the game do? Right now it just assumes that LOS is lost for good and fires an unobserved fire mission. While it might be better in some situations to have the game add another minute of delay to the fire mission in the hopes that LOS will be clear next turn, this won't always work. If the spotter has lost LOS for some reason other than smoke / dust, he may never regain it. If the spotter has moved behind an obstacle, or a burning vehicle or terrain tile is not blocking the LOS, it will never clear and the fire mission would be endlessly delayed.

Assuming the code can easily determine why LOS is blocked, a compromise solution might be to add another minute to the delay if dust or white smoke is blocking the LOS, while just firing the blind strike if terrain or black smoke is blocking.

[Treeburst155]

Big News! I decided to test this in CMBB. This behaviour is true in CMBB too. We just didn't notice because smoke clouds are much less common than dust clouds. With CMAK we have obstructions constantly.

If spotter LOS is blocked at the beginning of the turn in which the first round is to be fired, you get a haywire strike. This behaviour has been with us for years! LOL!! The dust just makes the situation occur MUCH more frequently.

I've a feeling BFC will not modify this behaviour. So, watch those dust clouds if your arty is due to fall next turn. Are you fighting a dry, dusty battle? Don't expect to get much out of your arty.

Treeburst155 out.

[Holman]

Treeburst,

I'm glad that you figured this one out. You should be on the beta test team!

I guess it's just one of those abstractions that we accept elsewhere, such as only giving new orders at precisely one-minute intervals. I'm just glad that the obstruction of LOS for direct fire doesn't work this way too.

[Treeburst155]

Martyr,

Yes, I should be on the beta test team to do the mind-numbing, repetitive testing of various in-game events, and unit behaviour that appears undesireable at first glance.

To open a new can of worms, are you sure direct fire doesn't stop when interrupted by smoke or dust? I think it probably does, but will resume again when LOS is restored. There are two kinds of direct fire to consider here, area fire and targetting units. Oh, let's not dig into this one. It doesn't get my platoons wiped out unexpectedly.

Treeburst155 out.

[Holman]

To open a new can of worms, are you sure direct fire doesn't stop when interrupted by smoke or dust?

Oh, it does, I know. What I meant was that I'm glad that direct fire is only blocked for the duration of the smoke or dust, rather than for a whole turn even after it clears. *That* would be bad...

[Treeburst155]

Well, with this little mystery solved, I'll be devoting more time to my PBEM battles now. That is, until the next mysterious game behaviour issue pops up. Thankfully, these are few and far between. Have fun guys, and watch that smoke and dust carefully.

Treeburst155 out.

[tar]

As far as a resolution of this goes, I think a reasonable behavior would be the following:

If the target was in LOS when the order was given, then the mission does not go to FFE until a spotting round is sighted. In other words, the FO will never end up with a blind strike if the initial call was visible.

If the target was out of LOS when the order was given, then the strike will arrive spotted or blind depending on whether LOS is available when the spotting round impacts.

I doubt that it is too hard to compute the LOS when the spotting round impacts, considering how often during the turn the game already has to compute LOS in order to let the TacAI make targetting decisions. This is a much simpler task -- namely an LOS check at one particular time during the turn generation. The LOS is from one location (the FO) to at most two others (the target & the spotting round).

Given John Kettler's remarks about artillery fire procedure, I think this gives a fairly realistic result. It may delay impacting rounds, but at least it doesn't cause other nasty surprises to the player. If the artillery doesn't come in when expected, then a player can investigate. The only way to get blind fire is to set up an explicit blind fire call. If you call for observed fire and then move the FO away, too bad for you, the mission is canceled -- so don't do that.

[GreenAsJade]

Originally posted by Steve McClaire:

I suspect that the current definition of the pr

I don't think BFC will consider this a bug, in the sense that what happens now is probably the intended behavior. [...]

If the spotter's LOS ends up blocked when the game is trying to resolve the spotting rounds and generate the turn's movie, what should the game do? Right now it just assumes that LOS is lost for good and fires an unobserved fire mission. [...] If the spotter has lost LOS for some reason other than smoke / dust, he may never regain it. If the spotter has moved behind an obstacle, or a burning vehicle or terrain tile is not blocking the LOS, it will never clear and the fire mission would be endlessly delayed.

I thought this is what is _supposed_ to happen!!

The spotting rounds are supposed to be spotted. If they are not, the battery is not supposed to just unleash firey death on some unsuspecting friendlies!

If the FO gets killed maimed or goes AWOL before the strike starts, isn't it supposed to be cancelled?

That would be the right behaviour, and if it can only be calculated based on LOS at the beginning of the turn, so be it... wait till next turn to see if the guy is going to be able to spot the rounds...

I think an implementation that requires the player to check an FO's LOS the turn before the rounds are due is ... um... (lost for words).

GaJ.

[Redwolf]

I agree with the solution proposal.

Whatever the reason is the engine decides the strike will be off-target - if you cannot fire spotting rounds while observing the desired impact point then delay further until LOS becomes clear, then fire spotting rounds and go FFE when it can be ensured the strike will be on target.

Going FFE after the spotter has seen it will be off-target is unrealistic, independently of when and how the engine decides it will be off-target.

But keep in mind there is a second bug that right now you don't only get a disadjusted strike at first, the adjustment of such a strike doesn't work either.

If the above bugfix(es) are made, I think it would be cool - and maybe doable if the code is touched anyway - to introduce a "hold" command which will keep an already targetted strike until you say it should go FFE. This would go a long way to a more realistic artillery model. The user interface could just be "pause strike for one turn", which you could give every turn as long as you wish. There is no complicated minute-specifying UI neccessary and this "hold one minute" functionality could maybe integrated into the coding for the "delaying" bugfix above.

[Redwolf]

Thanks to getting my cold back I can now verifying the following. It

is pretty random.

Findings which need to be formed into a theory:

1)

You see that Treeburst revised his reports from "LOS block at any time

during targeting will trigger the bug" to "LOS at the beginning of

the turn will trigger the bug".

That is not strictly correct, it is just the normal case. Normally,

the intermediate LOS block that clears up will not make it-off-target.

However, I have such a case. In this case LOS was blocked the turn

before either spotting or FFE rounds would fall but the beginning of

the turn was clear. The spotter fires 1(!) spotting round and then

fires off-target.

Here is it.

First picture:

Beginning of turn, note that smoke is not blocking LOS:

Spotting round falls, note craters to the right

FFE salvo comes off-target, note more craters to the right. Also note

ammo count indicating there has only been one spotting round.

Adjusting this strike does not work, although LOS is clear at the time

of adjusting it does not go on-target, it goes to a new random

location (note craters of several salvos to the left):

So there is something to Treebursts initial findings that LOS block at

other times than turn begin of firing triggers the bug, it is just

rare. Normally the bug is triggered by LOS block at the beginning of

the firing turn, but not always.

Savegame of this run after the first FFE volley:

http://redwolf.dyndns.org/tmp/artysmoke/case1-1.cmg

Running the following savegame (just hit GO) will often show you this

sequence. But since non-PBEM savegames are not guaranteed to show you

the same results YMMV. I ran it a few times and it always had an

off-target strike with one spotting round and clear LOS at spotting

round and FFE time

http://redwolf.dyndns.org/tmp/artysmoke/case1a.cmg

EDIT: this one is a straightforward case. LOS is blocked at the time spotting rounds would fall, and although it is clear at FFE time no spotting rounds come and strike is off-target.

http://redwolf.dyndns.org/tmp/artysmoke/case2a.cmg

EDIT: Straightforward case that intermediate LOS block does normally not harm. Smoke will disappear before spotting rounds, you get two spotting rounds and on-target FFE:

http://redwolf.dyndns.org/tmp/artysmoke/case2a.cmg

I had one case which I didn't save where I got two spotting rounds and off-map FFE. Stand by. That was with the smoke being there at turn beginning time but disappearing before the spotting rounds come. So the spotting rounds depend on LOS at that moment and FFE accuracy depends on LOS at turn beginning.

[ March 27, 2004, 09:34 PM: Message edited by: redwolf ]

[John Kettler]

This just gets better every day. One of the most useful threads we've had in quite a while.

redwolf, I totally support a Hold command, from both a procedural and historical standpoint. The famous "Up Front" cartoon (Willie and Joe are foxholed under a StuG) in the CMAK manual being a particularly telling example of its utility.

Regards,

John Kettler

[Holman]

Redwolf,

I notice that your rounds after adjustment are (while still off target) much closer to the intended target. This is consistent with a pattern I've noticed in my tests: adjustments might not be on-target precisely, but they're closer (and sometimes close enough for government work).

Has anyone noticed whether this is the case more often than not? If so, it might be another instance of Working As Designed. Perhaps the (high) chance of adjusted fire still being off-target is the price you pay for adjusting a plot that (as far as the game is concerned) was blind at the beginning. Retargetting (blue line) with clear LOS will clear up the problem, but of course takes more time.

Just wondering. If it's a bug, I definitely hope it will be fixed.

[Treeburst155]

Spotting rounds is another investigation. I've seen spotting rounds with the 155mm that preceded (by 50 seconds) a bad strike. I think the best way to keep from being bit by the issue is to make sure that LOS is clear on the turn the very first round is due to be fired, whether that is a spotting round or not.

Treeburst155 out.

[Treeburst155]

Dang it, Redwolf! You just disproved my bug definition! I ran your "Case_1a". The LOS clears 10 seconds before the end of the turn, but the strike still goes haywire, albeit with a spotting round.

My latest theory is that larger arty does not behave the same as 105mm and smaller. I think this because of the spotting rounds that are fired even when the strikes go bad. So, it's back to the drawing board. I still cannot protect my men from these haywire "observed" strikes in every case. There just has to be a way to pin this down. Hopefully it's not some random thing that happens.

Treeburst155 out.

[Redwolf]

Originally posted by Treeburst155:

My latest theory is that larger arty does not behave the same as 105mm and smaller. I think this because of the spotting rounds that are fired even when the strikes go bad.

No, the probably only appears that way.

From my observation, the decision spottings rounds yes/no is made on the fly in that second, the decision accurate or not is based on turn beginning.

However, small and big artillery modules differ in that the larger modules have a longer pause between spotting rounds and FFE rounds and hence and subject to entirely different mechanism when LOS varies around that time. Your observations might seem confusing because of this although they might still behave according to the same underlying rules.

I gave up on showing that case I mentioned, it is too damn hard to produce smoke that disappears at the right moment. I spend half an hour turning Hummels so that the smoke is delayed by the time it take to turn back and whatnot, but it's too tedious. Hope you take my word for it that there was a case with two spotting rounds and off-target when LOS was blocked at turn beginning and not blocked at spotting round time, and spotting and FFE were in the same turn.