LOS errors

[c3k]

Gents,

I'm playing Al Amarah. The scenario features an elevated road, about 2 stories high, with some craters on its surface. (It simulates having been bombed and has a dropped bridge as well. A very nice effect by the designer!)

I moved a 2 man sniper team into some of the road surface craters. From there, using my player's eye-of-god, I can see all the rooftops in the town. (This is scrolling down to the lowest level.)

My men are in the craters, with their heads up. They look good.

However, in game, my men are blind.

The LOS from the sniper team is being drawn from a point slightly lower than their belt buckles. Since they're prone, that point is subterranean. The Target line shows blue (valid LOF) where it comes out of the side of the elevated road. It turns Pink in midair a slight distance further away.

This is wrong.

It seems that what is happening is that the start point for the LOS is underground. That obviously would block LOS. The grid to calculate (or show) LOS extends beyond the confines of the road. Therefore, the valid LOS is an artifact of that grid. As soon as the next grid is entered the LOS block occurs and is shown.

Right now the game does not function well with elevation changes. By that, I mean that the TacAI has difficulty placing troops; LOS/LOF is non-reciprical; LOS/LOF is blocked when it seems it shouldn't be.

(Savegame available upon request; Al Amarah 008b 004/5)

Comments?

Thanks,

Ken

[hoolaman]

If a unit pops up on the roof, can you fire at it?

[c3k]

Excellent question: No.

There are several "?" contacts on rooftops as well as several identified infantry contacts. None of them are visible to the sniper team.

On the other hand, that has increased their survivability somewhat.

I'm playing on Veteran level. That allows the knowledge of all enemy contacts and the ability to see which of my units can see which enemy.

Regards,

Ken

[dan/california]

This strike me as something that Charles could fix when he finds the time.

[Paper Tiger]

Sounds like your units have LOS into an adjacent action spot but not one beyond that. Perhaps if you got them to crawl to the edge of the crater, you'll find they can see further. Very easy to do if you play in RT, not so good if you play WEGO though...

I feel for players who play WEGO because the Hunt command is pretty much nerfed now. Units move cautiously towards their waypoint and spot something and then drop prone. However, they often lose sight of that target and can't fire on them. Because I play in Real Time I can micromange them after contact to move into a position to fire on that unit but I can imagine how frustrating it must be when it happens in WEGO and you just have to watch your units go prone and do nothing for most of the turn.

I'm sure that as time goes by the game engine will be tweaked to take more and more advantage of the sophistication of the excellent new ELOS system. Because I play RT Elite, I use Hunt to gather information on the enemy's dispositions without taking significant casualties, in fact often none. Then, I know the unit is there but I can't fire on it but that intel is invaluable and I can then develop a plan to take the position out.

[c3k]

Paper Tiger,

No, they are, visually anyway, right at the edge of their own craters with their heads up. The LOS is blocked because it is being started from beneath their stomachs. That puts it underground.

Regards,

Ken

[Paper Tiger]

Then it's just one of the abstractions that the game uses. The ground in the crater is at level 1 while the ground around it at level 2. Because the units are prone, LOS is calculated from level 1. If they were kneeling in the crater, I suspect LOS would start at level 2, above the crater. Standing in the crater, they'd check LOS from level 3. If that's a roughly accurate assessment, then I think that's a hell of a lot better than anything I'd expect from a tactical wargame. We might have to wait a long time for a game of this scale that calculates LOS from the soldiers eyeballs wherever they may be.

[Battlefront.com]

Paper Tiger has it right. Remember, there aren't an infinite amount of heights that are checked, just the 5 that were introduced with ELOS. If your guys are prone they are taking cover and therefore can't see anything unless it was somehow above them (like the craters being in the floor of a valley and the enemy up on a cliff). Likewise, nobody should be popping shots at your guys either. That's the way it should be.

Now, if the units in the craters go to a kneeling position, then they will be minimally exposed (basically chest up), which means they can spot things that are at the same level or higher. It also means things can shoot back at them if they are at the same level or higher.

This all seems to be working as it should be so I'm curious about why c3k thinks it should work differently.

Steve

[dan/california]

Is there a ay to make them kneel?

[Martin Krejcirik]

What is needed is to allow prone units to place a target line even when they have no LOS (red line). It should tell them to try actively enagage the target, ie stand-up.

[c3k]

Steve,

Thanks. The craters are in an elevated road. Next to the elevated road is a town. All of the buildings are two stories. From the center of the elevated road a LOS/LOF should exist to the roof level of the buildings.

__/\__B B B

The inverted "v" is the road and the "B"s are buildings. It's not quite to scale.

The road surface can be swept with fire from many of the rooftops and quite a few second floor windows.

Men ON the road get hit. "Aaaarrrgghhhh, my leg!"

Men ON the road can return fire and hit the enemy in and on those buildings. "(Insert Syrian yell of pain)!"

Now, the ONLY shelter ON that road is a set of craters. Getting a sniper team in there should allow me (in my view) to fire on the same spots which are shooting at the road.

I want the LOS/LOF to be horizontal, if not slightly vertical, from the craters. The sniper team has their heads and weapons up out of the craters. They are looking out.

Savegame available.

I did not make the terrain juxtapositioning clear in my original post.

As for prone equating no LOS, I'm confused. (From Steve's post; "If your guys are prone they are taking cover and therefore can't see anything unless it was somehow above them...") I take that to only apply to prone men IN craters. Is that correct?

To emphasize: I am trying to fire at same level or slightly higher targets. The men seem to be looking out of the craters.

Thanks,

Ken

[hoolaman]

Hi Ken,

I know the exact spot on that map that you are referring to, and I have seen some funny things going on there before, with the rooftops being at the exact height of the road, it's an unusual terrain setup. Can you send the save to the email in my profile if you don't mind, I'm curious to see exactly what you are talking about.

[Battlefront.com]

c3k,

I can picture what you're saying, but you have to look at it from the perspective that there is no such thing as being 98% in a crater and 2% exposed when prone. If you have guys in the crater then they are, by definition, not at the same level as the road. They are lower. And that means that they can't engage targets at the same height as if they were on the road, nor can enemy units target your guys as if they were on the road. It works both ways.

However, if your guys are not prone (i.e. they are kneeling or standing), that's a totally different thing. Now they are partially exposed and can be targeted by enemy as well as being able to target them. The level of protection will be superior to the road.

The way to have your guys not be prone is to not give them a Hide Command. Obviously there are factors outside of your control that can make guys go prone, such as being shot at or cowering. That's the way it works in real life... when someone decides it is better to take cover than to be exposed to fire, they take cover. By definition taking cover means breaking LOS/LOF with the enemy and that break must be both ways.

Martin, you should be able to target spotted enemy units regardless of current LOS status. Whether or not your unit decides to change posture to get LOF is situationally dependent.

Steve

[c3k]

Steve,

Thanks. I'm working on posting screenshots. That should save, oh, 1,000 words per picture. Give or take.

My snipers (yeah, MINE; I bought the game, so now I own them... ) are not pinned. Their suppression meter is totally blank. The 2% exposed over the rim of the crater is their head and weapon.

Hoolaman, savegame on the way. (Post a screen if you want. I'm being pulled on errands right now. When I get back I'll open an imageshack or photobucket account and try to do so myself.)

Thanks,

Ken

[Battlefront.com]

c3k,

What I'm saying is that if they are in the crater, and they are prone, that is what matters. It doesn't matter why they are prone, nor how many pixels their heads are above the crater since the game doesn't differentiate to that degree. It's either prone, kneeling, or standing for infantry, nothing inbetween each.

This is not perfect, of course, but it is a lot better than it used to be and the way almost all wargames ever made are (i.e. one fixed height with modifiers to fudge posture).

Steve

[c3k]

Steve,

I'm not sure I understand: Are you saying that prone=no LOS? Or are you saying prone=no LOS to anything at the same level or lower?

You're going to force me to register at Image Shack, aren't you?

Thanks,

Ken

[c3k]

Right, time for some screen shots....

Here's the view....

Here's a closup from road level:

Here's a comparison how the other friendlies, prone along the road CAN fire:

Finally, moving the target line around shows this:

These should help show what I'm talking about.

Thanks,

Ken

[drtechno]

I love how people can't handle abstractions at this scale. No wonder doing 1:1 man scale is a pain in the rear end.

Regarding the screenshots:

As Battlefront.com said(no he doesn't have a name, heh), they are prone, in a crater (elevation of -1) so the don't have LOS, end of story. Doesn't matter how many pixels are over the edge of the crater (screenshot 2). Its an abstraction.

edit- However, I don't understand the last screenshot if the -1 elevation rule holds true... unless the elevation of the road increases in that direction (looks flat to me tho)

[c3k]

drtechno,

Thanks. I'm fine with abstractions. But since it doesn't matter what it looks like, that they are prone in a crater therefore LOS is blocked, how do you explain the bottom screenshot?

I am aware that this may be an outlier condition. That strange effects may occur at this given set of conditions. My main point being that if something strange is occurring (not sure if that's true or not), is it MEANT to occur this way? If it is, fine. This thread will wither away and die the death of an answered thread.

If it's NOT supposed to work the way I'm seeing it, can it be fixed? Does it highlight an algorithm oddity? Can, or should, the code be tweaked?

That's all.

Thanks,

Ken

[drtechno]

Absolutely right c3k.. I don't understand the last screenshot. I'll be curious what is said.

[c3k]

No rancor intended to you, drtechno, but please don't put me in the same category as people who never wanted to like this game and therefore pick it apart mercilessly.

Your post, three upstream, started with, "I love how people can't handle abstractions at this scale." That is a disparaging start. Credit to you for the edit you added and for taking the time to look harder at the situation.

It seems to me that the problem with the craters is that the ELOS is starting the LOS from inside the crater and then ignores the terrain clipping issue. A solution would be to raise the prone ELOS from belly level to a slightly higher point. Or, block LOS completely if partially clipped (that could have a lot of repercussions).

Lastly, BF.C could just note it as an unlikely to recur aberration and advise me to press on and ignore it.

Thanks,

Ken

[birdstrike]

I can't say for sure, but it seems the roof you're looking at in the 1st screenshot is below the street level of your snipers, or at least there is not enough of the roof visible to give them a viable LOS to the spot (for example to area fire the building). What seems odd to me is that the LOS-line is blue at the beginning. Have you been able to engage enemies on the roof of that buidling (or any adjacent building)?

In the 3rd screenshot it seems alright the snipers have a LOS out of the crater but the reverse slope is out of place.

But again there is no unit. From my experience I would expect any unit at the same spot (reverse slope) would still be visible and in LOF despite what the LOS to the ground says.

EDIT: before I make any assumptions here, there is a known issue with ELOS and low walls (discussed in another thread) - if this is also related to the same issue, any unit on the reverse-slope spot should not be visible. Can you check this C3K? Maybe by moving another friendly unit there? (when it's safe)

[c3k]

Birdstrike, I'll try. Of course, every time I move a blue unit I hear "allah akbar" or somesuch, and I'm left looking at a series of red pulsing circles...

Look closely....

Straight view across the road...

A unit able to shoot across the road at the rooftops...

A funny thing, this. He cannot see across the road. BUT, he can shoot at the tree!! Well, he can target it, but it won't take the final click.

For a few seconds there I flashed to Crysis. I planned to shoot down the tree, use stealth to grab the coconuts, then use superstrength and use the coconuts to kill the North Koreans. Err, Syrians...

Thanks,

Ken

[meade95]

Originally posted by drtechno:

Absolutely right c3k.. I don't understand the last screenshot. I'll be curious what is said.

+ 1

[birdstrike]

Originally posted by c3k:

[QB] Birdstrike, I'll try. Of course, every time I move a blue unit I hear "allah akbar" or somesuch, and I'm left looking at a series of red pulsing circles...

I know that problem

I used the editor to put the squads in the same locations as in your screenshots and got the same results as you showed, except for the palm tree.

I also put enemy units on some roofs to check if they are visible. The sniper unit in the crater was unable to see them.

For the "tree guys": I got a grey LOS to both the tree and the roofs beyond. units on the roof could be attacked by part of the unit - it was also easy to pinpoint which soldiers were in LOS to the roof since they were the only ones who fired. To make my point, soldiers who were further up to the crest could see the target, those behind the wall to the right (bridge) and further down, couldn't. This would seem the LOS mechanism works correctly here, and it's an issue of units not positioning themselves on the ridge for the whole unit to have a LOS on the target.

In the 3rd picture (3 MG guys looking at roofs) this seems to work as it should. Units are positioned up on the ridge, no LOS problems.

The LOS for units in the crater does not seem to work properly because the units are prone and are thus considered not to look over the edge of the crater (if I had to make a guess I'd say it is related to the issue I mentioned before - see also the thread here)