1.20: Steep Slope LOS Inconsistency

[Thomm]

My first test of the 1.20 code involves LOS across steep slopes.

There seems to be a 'blind zone' that I have no explanation for.

Since I am too bored to go through the screenshot routine, let me describe the simple setup:

a) Paint two parallel strips of fixed elevation of 20 m and 40 m, respectively, with two strips left 'white' separating them.

Place a team on the upper terrain edge.

Check LOS in the editor:

The lower terrain edge starts at a distance of 32 m. From 32 m to 39 m, area fire is possible.

From 40 m to 52 m, no LOS is indicated.

From 53 m to 59 m, the description reads 'Reverse Slope - No Aim Point'

Beyond 60 m, there is clear LOS again.

So how is it possible that there is LOS down the slope, then no LOS at intermediate range, and then free LOS again further out? :confused:

Best regards,

Thomm

[Battlefront.com]

Thomm,

Indirect fire weapons, most likely grenades in this case, can be used in the close distance, between 40-52m you don't have LOS and don't have the range for grenades, then you have LOS again from 60m on out for use with direct fire.

If we didn't show clear LOS for use with grenades then you wouldn't know to target there.

Make sense?

Steve

[Thomm]

I think it is a little bit more complicated than this.

First off, all LOS problems vanish if at least one soldier is kneeling instead of lying prone. Which makes sense as long as the LOS-from-body-center logic is considered. Kneeling soldiers could ambush down that slope, prone ones cannot. But how do you make the soldiers get on their knees if they are prone?

If all soldiers are prone, I could not area target anything close by, either. This contradicts your explanation. I can also not make them throw grenades over a wall (indirect fire out of LOS).

Best regards,

Thomm

[Thomm]

Prone British soldiers on the 40-?-?-20 terrain edge are given an area fire order towards the bottom of the slope, which is accepted by the engine. The displayed range is 34 meters.

No grenades are thrown.

The soldiers are stuck in 'Aiming - Waiting - Spotting' loops.

Is this working as desired?

Best regards,

Thomm

[Thomm]

Answer to self: Yes, because 34 meters appears to be outside of the throwing range of a prone soldier. At a shorter distance, grenades are flying. The UI does not take into account that the prone soldiers have a shorter throwing range.

Best regards,

Thomm

[Battlefront.com]

OK, everything looks fine. I'm pretty sure the UI isn't sensitive enough to show LOS below 1 Action Spot, which means there is an range of UI error of +/-8m.

Steve

[Thomm]

OK, everything looks fine.

The issue remains that the prone soldiers cannot see/attack any target below while their heads and weapons are clearly visible from below (not WYSIWYG). But this has been discussed already.

Now, if only there was a way to control the posture of the soldiers at the edge, the problem would be almost solved, because kneeling soldiers can peek over the 40-?-?-20 edge!

In my test, an Elite Small Unconventional Fighter group at the bottom of the slope nearly wiped out a platoon of British soldiers at the top of the slope without taking any casualties before I cancelled the battle. This should indicate that there still is a problem ...

Best regards,

Thomm

[Battlefront.com]

Thomm,

The issue remains that the prone soldiers cannot see/attack any target below while their heads and weapons are clearly visible from below (not WYSIWYG). But this has been discussed already.

Yes it has And as discussed below, "clearly visible" is really only a graphical issue and not a gameplay one. As far as the game is concerned they are hidden in relation to any spot they can't see.

Now, if only there was a way to control the posture of the soldiers at the edge, the problem would be almost solved, because kneeling soldiers can peek over the 40-?-?-20 edge!

We'll continue to tweak the TacAI over time, however we'll never allow micromanagement of individual soldiers. Definitely not a road we want to go down. There are far better ways to get what will amount to a very small improvement without creating other major problems.

In my test, an Elite Small Unconventional Fighter group at the bottom of the slope nearly wiped out a platoon of British soldiers at the top of the slope without taking any casualties before I cancelled the battle. This should indicate that there still is a problem ...

If you have a save, we'll look at it. But I highly doubt there is a problem. At least not with LOS/LOF or perhaps even Spotting. Try the same test with an Elite British unit at top and a Conscript down below and see what the results are. My guess is you won't be able to reproduce the same results.

Since the beginning of CM's development people have been able to create test scenarios that "break" certain functions, yet nobody can point to such a situation actually happening within a real game. Or at least out of thousands of games may only find it happening once or twice. "Tests" tend to be extremely unreliable in that sense. At least for things which are complex in nature where specific variables are very, very important and yet aren't scientifically accounted for by the tester.

Steve

[JonS]

Now, if only there was a way to control the posture of the soldiers at the edge, the problem would be almost solved, because kneeling soldiers can peek over the 40-?-?-20 edge!

but there is a way to control their posture. Give them a hide order, let it ride for a while (at least one turn in TBP), then cancel it. Some number of the guys will got to the knee.

Alternately, have them move away from the lip then back to it. Some number of the guys will probably remain standing.

et voila. Two ways!

[Battlefront.com]

BTW, another reason I doubt there's a LOS/LOF issue here... we haven't had any in a very, very long time. The new behavior for things like lips of hills is simply TacAI changes to make the use of such a position more effective. The actual LOS/LOF code hasn't been changed. So even if there is some sort of problem here, and personally I don't think there is (without seeing the actual file I can't say for sure!), it's about TacAI behavior and not the underlying system. Which is very important to us since these are completely different things.

Steve

[CptWasp]

I agree that there is some problems with hills. It's not a bug, LOS works well; it's how the game manages combat from hills.

A premise:

In reality soldiers are normally instructed to defend high terrain deploying not just on the reverse side of a hill or crest, because on the crest line you are very visible from below.

So you have two options: if the enemy occupies another hill in front of you, you can position yourself on the reverse side of the hill, but distant from the crest line, taking in your LOF the crest line; it's a risky thing, because you will see the attacking enemy later, but for Germans in the Montecassino area worked well. If the enemy in UNDER you, you can deploy on the front side of the hill, under the crest line. This is normal procedure for Italians Alpini too.

In CMSF the first tactic works well... maybe TOO well! If you deploy on the reverse side at effective weapon range you will deliver havoc on attackers. They are exposed on the front side of the hill during attack, and before they can find cover and identify attackers they will be decimated.

But the second one doesn't work at all. Simply put, defending from high terrain gives more problems than advantages in CMSF. And the basic problem is in LOS.

On steep hills I have a very difficult time finding a place with a good LOS on troops directly under me. They see me, and fire; I don't see them well, or more often I have LOS and no LOF (they are on "the reverse side" for the LOS tool and I con't fire).

I think that the cause is in the LOS system itself: in the real world, when you are in a high position and you are defending against troops under you, you will position yourself prone, exposing only head and arms, taking under aim the terrain under you without becoming exposed with the body. IN CMSF this doesn't work, because troops firing from above see the enemy under them only exposing themselves (usually with devastating losses).

A possible solution could be tracing the LOF (ONLY for units on hills, and only if firing to an enemy under them) from a point A LITTLE higher than the "graphical" head of the soldier, giving him a better view of the terrain under him.

Ok, very long post, sorry; what I say is that when I'm on hills I feel myself too much vulnerable, more than I feel it should be in real world.

(I copied this post from another thread, I missed this one and so started another very similar, sorry)